JP2016040037A - Compact wastewater concentrator and contaminated material scrubber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid concentrator that functions to concentrate wastewater stream having broad characteristics with cost efficiency.SOLUTION: A gas inlet 20, a gas exit 22 and a flow corridor 24 connecting the gas inlet 20 and the gas exit 22 are included, wherein the flow corridor 24 includes a narrowed portion 26 that accelerates the gas that passes through the flow corridor 24. A liquid inlet 30 injects liquid into the gas stream at a point prior to the narrowed portion 26, so that the gas-liquid mixture is thoroughly mixed within the flow corridor 24, causing a portion of the liquid to be evaporated. A demister 34 or fluid scrubber provided downstream of the narrowed portion 26 removes entrained liquid droplets from the gas stream and re-circulates the removed liquid to the liquid inlet 30 through a re-circulating circuit 42. Fresh liquid to be concentrated is also introduced into the re-circulating circuit 42 at a rate sufficient to offset the amount of liquid evaporated in the flow corridor 24.SELECTED DRAWING: Figure 1

Description

  This application is a continuation-in-part of US patent application Ser. No. 12 / 705,462 (filing date: February 12, 2010). US patent application Ser. No. 12 / 705,462 is a continuation-in-part of US patent application Ser. No. 12 / 530,484 (filing date: September 9, 2009). US patent application Ser. No. 12 / 530,484 is a US national phase application of International (PCT) patent application No. PCT / US08 / 56702 (filing date: March 12, 2008). Claims the benefit of 906,743 (filing date: March 13, 2007). This application also includes US Provisional Patent Application No. 61 / 152,248 (filing date: February 12, 2009) and US Provisional Patent Application 61 / 229,650 (filing date: July 29, 2009). Insist on the benefits of priority. In this specification, the entire disclosure of each of the applications 12 / 530,484, 60 / 906,743, 61 / 152,248 and 61 / 229,650 is expressly incorporated by reference.

This application relates primarily to liquid concentrators, and more particularly to wastewater concentrators that are compact, portable, and cost effective. The waste water concentrator can be easily connected to a waste heat source and can easily use the waste heat source.

The concentration of volatile materials can be an effective form of treatment or pretreatment of a wide variety of wastewater streams and can be performed in various types of commercial treatment systems. At high levels of concentration, many wastewater streams can be reduced to residual material in the form of a slurry containing high levels of dissolved and suspended solids. Such concentrated residues can be easily solidified by conventional techniques and then landfilled in landfills or, if applicable, sent downstream processes for further processing before final landfill You can also. Concentrating the wastewater allows for significant reductions in transportation costs and required storage capacity, and may also be useful in downstream processes that perform material recovery from wastewater.

The characteristics of industrial wastewater streams vary widely depending on the numerous industrial processes from which they originate. That is, in addition to wastewater generated due to design under controlled conditions in the industry, wastewater is often generated due to uncontrollable situations caused by accidents and natural disasters. Technologies for wastewater control include direct drainage to sewage treatment plants, drainage to sewage treatment plants after pretreatment, onsite or offsite processes for recycling useful components, wastewater before final landfill There is on-site processing or off-site processing that performs only adjustment. If the wastewater source is uncontrollable, effective containment and recovery techniques should be included in any of the above options.

An important measure of the effectiveness of the wastewater concentration process is the ratio between the volume of generated residue and the volume of wastewater entering the process. Specifically, the lower the ratio between residue volume and feed volume (high level concentration), the more desirable. If the wastewater contains dissolved and / or floating non-volatile materials, the volume reduction achievable in certain concentration processes that rely on evaporation of volatile materials is due to heat transfer to the process fluid. Depending on the method chosen, it is greatly limited.

In the case of conventional processes, the concentration due to evaporation of water and other volatile substances is affected. Conventional processes can be categorized as direct heat transfer systems or indirect heat transfer systems, depending on the method of heat transfer to the liquid being concentrated (process fluid). Indirect heat transfer devices mainly include jacketed tubes or plates, bayonet tubes or coil heat exchangers. The jacketed tube contains a process fluid. The plate, bayonet tube or coil heat exchanger is immersed in the process fluid. A medium (eg steam or hot oil) is sent through the jacket or heat exchanger for the heat transfer required for evaporation. In a process performed by a direct heat transfer device, the heat medium is brought into direct contact with the process fluid. Such direct contact occurs, for example, in an underwater combustion gas system.

Indirect heat transfer systems that rely on heat exchangers (eg jackets, plates, bayonet tubes or coils) are often limited by solid build-up on the heat exchanger surface in direct contact with the process fluid. Also, in the case of such systems, a separate process (eg, a device used to heat a steam boiler or other heat transfer fluid (eg, a hot oil heater)) required for the transfer of thermal energy to the heat medium. As a result, the system design is complicated. Due to this design, two indirect heat transfer systems are required to support the concentration process. A feed stream that generates deposits on the heat exchanger during processing is called a fouling fluid. When certain compounds (eg, carbonates) whose solubility decreases with increasing temperature are included in the feedstream, accumulations (generally at lower concentrations due to increased temperature on the surface of the heat exchanger) (Known as boiler scale) occurs. Furthermore, if a compound (eg, sodium chloride) that increases in solubility with increasing temperature is present in the wastewater feed, the compound also precipitates deposits from the solution as the process fluid is concentrated. With such deposits, it is necessary to frequently clean the heat exchange surfaces to maintain process efficiency. Such deposits can be any combination of suspended solids that are transported into the process with the wastewater feed and solids that settle out of the process fluid. Due to the adverse effects of such solid buildup on the heat exchange surface, the length of time that the indirect heat transfer process can be operated is limited. This is because the process needs to be interrupted in order to perform regular cleaning. Thus, due to such adverse effects, the effective control range of wastewater is actually limited, particularly when the wastewater range includes fouling fluid. Therefore, processes that rely on indirect heat transfer mechanisms are often unsuitable for concentrating a diverse and wide range of wastewater streams and reducing the ratio of residue to feed volume.

In Patent Document 1 (which is incorporated by reference), there is a disclosure of a specific type of direct heat transfer concentrator. This direct heat transfer concentrator takes the form of an underwater gas process, generating combustion gases and passing them through an inlet pipe to a dispersion unit in the process fluid. The dispersion unit includes a plurality of spaced gas delivery pipes. These gas delivery pipes extend radially outward from the inlet pipe. Each of these gas delivery pipes has a small hole. These small holes are spaced at various positions on the surface of the gas delivery pipe, thereby distributing the combustion gas as small bubbles as uniformly as possible on the cross-sectional area of the liquid held in the processing tube. Let According to the current understanding in the prior art, this design allows the liquid and hot gas to be desirably in intimate contact over a large interfacial surface area. The intent of this process is to generate heat and mass transfer at the dynamically and continuously reproducible interfacial surface area formed by gas phase dispersion in the process fluid, at solid heat exchange surfaces where solid particle accumulation can occur. Is to prevent heat and mass transfer. Therefore, if this underwater gas concentration process is used, a significant advantage is obtained as compared with the conventional indirect heat transfer process. However, in the case of U.S. Pat. No. 6,057,056, small holes in the gas delivery pipe used to disperse hot gas within the process fluid within the device are plugged due to solid buildup formed from the fouling fluid. As a result, solids accumulate in the inlet pipe which is the hot gas path to the process fluid.

Furthermore, since it is necessary to disperse a large amount of gas in the entire continuous process liquid phase, in Patent Document 1, it is often necessary to extremely increase the cross-sectional area of the confinement tube. The inner surface of such a containment tube and any attachments attached within the containment tube are collectively referred to as the “wetting surface” of the process. These wet surfaces need to withstand various concentrations of hot process fluids during system operation. For systems designed to handle a wide range of wastewater streams, critical design considerations are determined in relation to both corrosion and temperature resistance based on the structural material of the wet surface. Corrosion and temperature resistance must be balanced against equipment costs and maintenance / replacement costs over time. Generally speaking, wet surface durability and low maintenance / replacement costs select either high-grade metal alloys or specific industrial plastics (such as those used in the manufacture of glass fiber tubes) It improves by doing. However, in the case of conventional concentration processes using either indirect or direct heating systems, there are also means for hot media (eg steam, heat transfer oil or gas for heat transfer to the fluid in the tube) Necessary. While a variety of different high alloys can provide answers for corrosion and temperature resistance, the costs of tubes and fittings made from such alloys are often very high. In addition, industrial plastics can be formed directly as a containment tube or used as a coating on a wet surface, but there are often limitations on the temperature resistance of many industrial plastics. For example, there is such a restriction in the case of the hot surface of the inlet pipe for hot gas in the pipe used in Patent Document 1. As such, the tubes and other equipment used in these processes are typically very expensive to manufacture and maintain.

Furthermore, in all of these systems, it is necessary to perform a concentration or evaporation process in the heat source. Many systems use heat generated by various sources (eg, heat generated in the engine, heat generated in the combustion chamber, heat generated in the gas compression process, etc.) as a heat source for wastewater treatment. Has been developed. An example of such a system is disclosed in Patent Document 2. In this patent, heat is generated by burning a landfill gas in an underwater combustion gas evaporator, and the leachate is processed at the landfill site using this heat. Patent Document 3 discloses an underwater gas evaporator. In this underwater gas evaporator, waste heat is provided to the input of the gas evaporator and used for liquid concentration or evaporation. Although waste heat is often regarded as a low-cost energy source, in order to effectively use waste heat in wastewater treatment operations, in many cases, waste heat is transferred from the waste heat source to the place where the evaporation or concentration process is performed. Often it is necessary to transport over long distances. For example, in many cases, in landfill operations, a generator using one or more internal combustion engines that operate using landfill gas as fuel is used. Exhaust from these generators or engines is typically sent through a muffler and exhaust stack to the atmosphere above the building containing the generator and becomes a waste heat source. However, in order to collect and use this waste heat, it is necessary to connect a large amount of expensive pipes and ducts to the exhaust stack and send the waste heat to the processing system position. Often on the surface of the ground away from the building containing the aircraft. Significantly, piping, duct materials and control devices (eg, throttle and shut-off valves) that can withstand high temperature (eg, 950 degrees Fahrenheit) exhaust gases in the stack are extremely expensive, and Insulation is also necessary to maintain the heat in the exhaust gas during transportation. Acceptable thermal insulation materials for such purposes often fail in general due to various properties (eg, brittleness, aging corrosion and sensitivity to thermal cycling), which complicates the design. Due to thermal insulation, the weight of piping, ducts and control devices also increases, resulting in an increase in the cost of structural support requirements.

US Pat. No. 5,342,482 U.S. Pat. No. 7,214,290 US Pat. No. 7,416,172

The compact liquid concentrating device disclosed herein can be easily connected to a waste heat source (eg, landfill gas flare or combustion engine stack), and this waste heat can be used to direct the heat transfer concentration process. This can be done without the need for large, expensive confinement tubes and without the need for large amounts of expensive high temperature resistant materials. The compact liquid concentrator includes a gas inlet, a gas outlet, and a mixing or flow passage connecting the gas inlet and the gas outlet. The flow passage includes a narrow portion. In the narrow portion, the gas passing through the flow passage is accelerated. From the liquid inlet disposed between the gas inlet and the narrow portion of the flow passage, liquid is injected into the gas stream at a point in front of the narrow portion, whereby the flow passage. Inside, the gas liquid mixture is thoroughly mixed and a part of the liquid is evaporated or concentrated. A demister or fluid scrubber is provided downstream of the narrow portion. The demister or fluid scrubber is connected to the gas outlet, removes entrained droplets from the gas stream, and recirculates the removed liquid to the liquid inlet through a recirculation circuit. New liquid to be concentrated is also introduced into the recirculation circuit at a rate sufficient to offset the sum of the liquid evaporated in the flow passage and the total concentrated liquid drawn from the process.

The compact liquid concentrator described herein includes multiple attributes that function to cost effectively concentrate a wastewater stream having a wide range of properties. The concentrator is resistant to corrosive action over a wide range of feed characteristics, has reasonable manufacturing and operating costs, can operate continuously at high levels of concentration, and is directly from a wide range of sources Use the obtained thermal energy efficiently. In addition, the concentrator is compact and portable, can be easily transported to a location where wastewater occurs with an uncontrollable event, and can be mounted close to the waste heat source. Thus, the concentrator described herein is a cost-effective, reliable, and durable device that operates to continuously concentrate a wide variety of different types of wastewater streams, and Eliminates the use of conventional solid surface heat exchangers in conventional indirect heat transfer systems (which caused clogging and buildup).

It is a general schematic diagram of a compact liquid concentrator. FIG. 2 illustrates the liquid concentrator embodiment of FIG. 1 mounted on a pallet or skid for ease of transport on a truck. FIG. 2 is a perspective view of a compact liquid concentrator performing the concentration process of FIG. 1 connected to a waste heat source generated by a landfill flare. It is a perspective view of the heat transfer part of the compact liquid concentrator of FIG. FIG. 4 is a front perspective view of the evaporator / concentrator portion of the compact liquid concentrator of FIG. 3. 4 is a perspective view of an easily openable access door on a portion of the compact liquid concentrator of FIG. FIG. 7 is a perspective view of one of the easily openable access doors of FIG. 6 in the open position. 8 is a perspective view of an easily openable latch mechanism used on the access door of FIGS. 6 and 7. FIG. FIG. 4 is a schematic diagram of a control system that can be used to control the operation of various components of the compact liquid concentrator within the compact liquid concentrator of FIG. 3. The compact liquid concentrator of FIG. 3 is shown attached to the combustion engine stack as a waste heat source. FIG. 3 is a general schematic diagram of a second embodiment of a compact liquid concentrator. It is a top view of the compact liquid concentrator of FIG. FIG. 6 is a schematic diagram of a third embodiment of a compact liquid concentrator, where the third embodiment is a distributed liquid concentrator. It is side surface sectional drawing of the liquid concentration part of the dispersion type liquid concentrator of FIG. It is a top view of the liquid concentration part of FIG. FIG. 14 is a detailed side view of the quencher and venturi section of the distributed liquid concentrator of FIG. 13. FIG. 2 is a perspective view of another embodiment of a compact liquid concentrator that performs the concentration process of FIG. 1 configured to remove ammonia from landfill leachate.

FIG. 1 is a general schematic diagram of a liquid concentrator 10. The liquid concentrator 10 includes a gas inlet 20, a gas outlet 22, and a flow passage 24 that connects the gas inlet 20 to the gas outlet 22. The flow passage 24 includes a narrow portion 26. In the narrow portion 26, the gas flow through the flow passage 24 is accelerated, resulting in turbulence in the flow passage 24 at or near this location. The narrow portion 26 in this embodiment can be formed by a venturi device. From the liquid inlet 30, the liquid to be concentrated (via evaporation) is injected into the liquid concentration chamber in the flow passage 24 at a point upstream of the narrow portion 26. The injected liquid merges with the gas flow in the flow passage 24. The liquid inlet 30 may include one or more replaceable nozzles 31 for spraying liquid into the flow passage 24. Regardless of whether the nozzle 30 includes the nozzle 31, the inlet 30 is parallel to the gas flow when the gas flows through the flow passage 24 (from a direction perpendicular to the gas flow to the gas flow). The liquid can be introduced in any direction (up to the direction). By providing the baffle 33 in the vicinity of the liquid inlet 30, the liquid introduced from the liquid inlet 30 collides with the baffle, and as a result, the droplets are dispersed in the flow passage into small droplets. .

As the gas and liquid flow through the narrow portion 26, turbulence is accelerated by Venturi's law, and the gas and liquid are thoroughly mixed in the flow passage 24 and after the position of the inlet 30. Due to the acceleration through the narrow portion 26, a shear force is generated between the gas flow and the droplet, and between the droplet and the wall of the narrow portion 26. As a result, Very fine droplets mix into the gas, which increases the interfacial surface area between the droplets and the gas and speeds up mass transfer and heat transfer between the gas and the droplets. To do. The liquid flows out of the narrow portion 26 regardless of the geometric shape of the liquid flowing into the narrow portion 26 (for example, the liquid can flow into the narrow portion 26 as a sheet-like liquid). When going, it becomes very fine droplets. As a result of turbulent mixing and shear forces, some of the liquid evaporates at high speed and becomes part of the gas stream. As the gas liquid mixture passes through the narrow portion 26, the direction and / or speed of the gas liquid mixture can be changed by an adjustable flow restrictor (eg, venturi plate 32). This flow restriction is typically used to create a large pressure differential in the flow passage 24 upstream and downstream of the venturi plate 32. The venturi plate 32 can be adjusted to control the size and / or shape of the narrow portion 26 and can be a corrosion resistant material (eg, a high alloy metal) (eg, Hastelloy®, Inconel®). And manufactured under the trade name of Monel®).

After exiting the narrow section 26, the gas liquid mixture passes through a demister 34 (also referred to as a fluid scrubber or entrainment separator) connected to the gas outlet 22. The demister 34 removes entrained droplets from the gas stream. The demister 34 includes a gas flow passage. The removed liquid collects in a liquid collector or sump 36 in the gas flow path. The sump 36 may also include a reservoir that holds the removed liquid. Liquid is returned through the recirculation circuit 42 to the liquid inlet 30 and / or the flow passage 24 by a pump 40 and / or reservoir fluidly connected to the sump 36. In this way, the liquid can be reduced to the desired concentration by evaporation. A new liquid to be concentrated is input to the recirculation circuit 42 through the liquid inlet 44. This new liquid may be injected directly into the flow passage 24 upstream of the venturi plate 32. The rate at which new liquid input is input into the recirculation circuit 42 depends on the evaporation rate of the liquid as the gas liquid mixture passes through the flow passage 24 and in the reservoir in the sump 40 or in the vicinity of the reservoir in the sump 40. And the sum of the velocities of the liquid extracted through the concentrated fluid extraction port 46 located in The ratio between the recirculated liquid and the new liquid can generally be from about 1: 1 to about 100: 1 and usually from about 5: 1 to about 25: 1. For example, if the fluid circulation rate in the recirculation circuit 42 is approximately 10 gal / min, new liquid can be introduced at a rate of approximately 1 gal / min (ie, in a 10: 1 ratio). When the liquid in the recirculation circuit 42 reaches a desired concentration, a part of the liquid can be sucked out of the extraction port 46. The recirculation circuit 42 functions as a buffer or buffer in the evaporation process, thereby ensuring sufficient moisture in the flow passage 24, thereby avoiding complete evaporation of the liquid and / or formation of dry particulates. Is done.

After passing through the demister 34, the gas stream passes through the introduction fan 50. The introduction fan 50 sucks gas through the flow passage 24 and the demister gas flow passage under a negative pressure. Of course, the concentrator 10 can also operate under positive pressure generated by a blower (not shown) provided in front of the liquid inlet 30. Eventually, the gas is released into the atmosphere or exits from the gas outlet 22 for further processing.

The concentrator 10 includes a pretreatment system 52 for processing the liquid to be concentrated. The liquid to be concentrated may be a waste water feed. For example, by using an air stripper as the pretreatment system 52, a substance that can be a source of malodor or a substance that is regulated as an air pollutant can be removed. In this case, the air stripper may be any conventional type of air stripper, or may be a further concentrator of the type described herein, used in series as an air stripper. It is possible. If desired, the pretreatment system 52 can heat the liquid to be concentrated using any desired heating technique. Further, the gas and / or wastewater feed circulating in the concentrator 10 can be preheated in the preheater 54. Preheating can be used to increase the evaporation rate and thus increase the liquid concentration rate. Through combustion of renewable fuels (eg wood chips, biogas, methane, or any other kind of renewable fuel, or any combination of renewable fuels, fossil fuels and waste heat) and / or Or the wastewater feed can be preheated. Further, the gas and / or waste water can be preheated through the use of waste heat generated in the landfill flare or stack. Also, waste gas from an engine (eg, an internal combustion engine) can be used to preheat the gas and / or waste water feed. Furthermore, natural gas can be used as a waste heat source, and the natural gas can be supplied directly from a natural gas source in an unpurified state, and supplied immediately after completion of a natural gas well before the gas flow is stabilized. Alternatively, it can be supplied after the gas flow is stabilized in the natural gas well that has become more stable. If necessary, the natural gas may be purified and then burned in the flare. In addition, the gas stream exiting the gas outlet 22 of the concentrator 10 may be sent to a flare or other post-treatment device 56 to treat the gas and release it to the atmosphere.

Using the liquid concentrator 10 described herein, a wide range of wastewater streams (eg, industrial wastewater, natural disaster effluent (flood, hurricane), refinery shochu, leachate (eg, landfill) Ground leachate), backflow water after completion of the natural gas well, and water generated due to the operation of the natural gas well). The liquid concentrator 10 is practical, energy efficient, reliable and cost efficient. In order to increase the usefulness of this liquid concentrator, the liquid concentrator 10 can be easily adapted to be mounted on a trailer or movable skid, thereby causing wastewater generated due to an accident or natural disaster. Wastewater generated at the site in remote locations that are spatially separated can be treated periodically, effectively dealing with flow. The liquid concentrator 10 described herein has all these desirable characteristics and provides significant advantages over conventional wastewater concentrators, particularly for the purpose of managing a wide variety of wastewater streams. To do.

Furthermore, the majority of the concentrator 10 is made from a highly corrosion resistant and low cost material (eg, glass fiber and / or other industrial plastics). This is possible in part due to the fact that the disclosed concentrator is designed to operate under minimal differential pressure. For example, typically only a differential pressure in the range of only 10-30 inches of water is required. In addition, from the gas liquid contact zone of the concentration process, high turbulent flow is generated in a narrow (compact) passage at the venturi portion of the flow channel or immediately after the venturi portion of the flow channel, so that the gas liquid contact is large. Compared to conventional concentrators that occur in the process tube, the overall design is very compact. As a result, the high alloy metal required for the concentrator 10 is extremely minimal. Also, because these high alloy parts are small and can be easily replaced in a short time and with minimal effort, lower quality alloys that should replace some or all of these parts regularly It is possible to further reduce the production cost by designing as a wear item manufactured from. If desired, these lower quality alloys (e.g., carbon steel) can be coated with a corrosion and / or corrosion resistant liner (e.g., industrial plastics containing elastomeric polymers) to provide the component The service life of can be extended. Similarly, by providing the pump 40 with a liner that has been subjected to corrosion and / or corrosion resistance treatment, it is possible to extend the life of the pump 40, thereby reducing maintenance costs and replacement costs.

As will be appreciated, the liquid concentrator 10 causes turbulent heat exchange and mass transfer between the hot gas and the liquid (eg, waste water being concentrated) by causing direct contact between the liquid to be concentrated and the hot gas. Is generated. Further, the concentrator 10 uses a very compact gas liquid contact zone, thereby minimizing the gas liquid contact zone compared to known concentrators. Such a direct heat exchange function promotes high energy efficiency and eliminates the need for a solid surface heat exchanger as used in conventional indirect heat transfer concentrators. Furthermore, the compact gas liquid contact zone eliminates the need for bulky process tubes used in both conventional indirect and direct heat exchange concentrators. With these functions, it is possible to manufacture the concentrator 10 using a relatively low-cost production technique, and the weight of the concentrator 10 can be made lighter than that of the conventional concentrator. These factors work together to increase portability and cost efficiency. Thus, the liquid concentrator 10 is more compact and lighter than conventional concentrators, making it ideal for use as a portable unit. Furthermore, the liquid concentrator 10 is less prone to fouling and clogging due to heat exchange work by direct contact and lack of the solid heat exchanger surface. The liquid concentrator 10 can also process liquids containing large amounts of suspended solids by direct contact heat exchange. As a result, a high concentration process fluid can be achieved without the need for frequent cleaning of the concentrator 10.

More specifically, in a liquid concentrator using indirect heat transfer, the heat exchanger is prone to fouling, and therefore a hot heat transfer medium (steam or other hot fluid) circulating in the heat exchanger. Corrosion is likely to accelerate at normal operating temperatures. Each of these factors imposes significant limitations on the durability and / or construction costs of conventional indirectly heated concentrators and interrupts the operation of the heat exchanger for cleaning or repair. The operating time until the time is also subject to significant restrictions. By eliminating the need for bulky process tubes, both the weight of the liquid concentrator and the initial and replacement costs of high alloy components can be reduced. Furthermore, the temperature difference between the gas / liquid, the relatively small volume of liquid contained in the system, the relatively large interface area between the liquid and the gas, and the relative humidity of the gas before mixing with the liquid The liquid concentrator 10 approaches the adiabatic saturation temperature in a particular gas liquid mixture. The adiabatic saturation temperature is typically about 150 degrees Fahrenheit to about 215 degrees Fahrenheit (ie, the concentrator is a “low momentum” concentrator).

Furthermore, the concentrator 10 is designed to operate under negative pressure, and this capability greatly improves the ability to use a very wide range of fuel or waste heat sources as energy sources for evaporation. To do. In fact, due to the traction of these systems, the gas used in the concentrator 10 can be heated and supplied using a pressurized or non-pressurized burner. Furthermore, since only a minimum number of moving parts and wear parts are required, the simplicity and reliability of the concentrator 10 is increased. Generally, the concentrator is on waste heat (eg, stack gas from an engine (eg, generator or vehicle engine), turbine, industrial process stack, gas compressor system, and flare (eg, landfill gas flare)). When configured to operate, only two pumps and a single draft fan are required. These functions provide a great advantage that the diversity of the concentrator 10 and the purchase cost, operation cost, and maintenance cost of the concentrator 10 can be preferably reflected.

Concentrator 10 can operate in an activated state or can operate in a steady state. In the activated state, the sump and recirculation circuit 42 of the demister 34 can be filled with fresh waste water. During the initial treatment, the new wastewater introduced into the inlet 30 is at least partially evaporated in the narrow portion 26 and accumulated in a more concentrated manner than the new wastewater in the sump of the demister 34. . Over time, the wastewater and recirculation circuit 42 in the demister sump 34 approaches a desired level of concentration. At this point, the concentrator 10 can be operated in a continuous mode. In continuous mode, the amount of solids drawn from the extraction port 46 is equal to the amount of solids introduced into the new wastewater through the inlet 30. Similarly, the amount of water evaporated in the concentrator 10 is replaced with the same amount of water in the new wastewater. Thus, the condition in the concentrator 10 approaches the adiabatic saturation point of the heated gas and wastewater mixture. As a result, the concentrator 10 becomes highly efficient.

FIG. 2 is a side view of the liquid concentrator 10 mounted on a movable frame 60 (eg, pallet, trailer or skid). The size and shape of the movable frame is sized and shaped so that it can be easily loaded or connected to a transport vehicle 62 (eg, a tractor trailer truck). Similarly, such attached concentrators can be easily loaded on trains, ships or airplanes (not shown) for rapid transport to remote sites. The liquid concentrator 10 can operate as a fully self-contained unit with a burner and fuel supply therein, or the liquid concentrator 10 can use an on-site burner and / or an on-site fuel or waste heat source. It can also be activated. The fuel of the concentrator 10 may include a renewable fuel source, such as waste (paper, wood chips) and landfill gas. Further, the concentrator 10 may operate with any combination of conventional fossil fuels (eg, coal or petroleum), renewable fuels and / or waste heat.

A concentrator 10 mounted on a typical trailer can process over 100,000 gallons of wastewater per day, while larger stationary units (eg landfills, sewage treatment plants, or natural) If installed in a gas field or oil field), wastewater of several hundred thousand gallons per day can be treated.

FIG. 3 shows one particular embodiment of a compact liquid concentrator 110. The liquid concentrator 110 operates using the principles described above with respect to FIG. 1 and is connected to a waste heat source in the form of a landfill flare. Generally speaking, the compact liquid concentrator 110 of FIG. 3 is a landfill flare that burns landfill gas in a manner that meets standards set by the United States Environmental Protection Agency (EPA) and / or more local regulatory authorities. It operates to concentrate wastewater (eg, landfill leachate) using exhaust or waste heat generated within. As is known, the flare contained in most landfills is used to burn landfill gas to remove methane and other gases and then release it to the atmosphere. Typically, the gas exiting the flare is 1200-1500 degrees Fahrenheit and can reach 1800 degrees Fahrenheit. The compact liquid concentrator 100 shown in FIG. 3 is equally effective in concentrated backflow or product water from a natural gas well and operates on exhaust gas from natural gas flares or propane flares at or near the source. Is possible. In some embodiments, the natural gas flare may be supplied with natural gas directly from a natural gas well.

As shown in FIG. 3, the compact liquid concentrator 110 generally includes or is connected to the flare assembly 115. The compact liquid concentrator 110 includes a heat transfer assembly 117 (shown in more detail in FIG. 4), an air pretreatment assembly 119, a concentrator assembly 120 (shown in more detail in FIG. 5), a fluid scrubber 122, And an exhaust part 124. Significantly, the flare assembly 115 includes a flare 130 and a flare cap assembly 132. Flare 130 burns the landfill gas (or other combustible fuel) within flare 130 according to any known principle. Flare cap assembly 132 includes a movable cap 134 (eg, flare cap, exhaust gas cap) or other type of stack (eg, combustion gas stack). The movable cap 134 covers the top of the flare 130. The other type of stack (eg, combustion gas stack) either seals the top of the flare 130 when the flare cap 134 is in the closed position, or partially redirects a portion of the flare gas in the closed position. Let The movable cap 134 allows gas generated in the flare 130 to escape to the atmosphere through the open end forming the main gas outlet 143 when the flare cap 134 is in the open position or partially in the open position. Flare cap assembly 132 also includes a cap actuator 135 (eg, a motor (eg, an electric motor, a hydraulic motor, a pneumatic motor) as shown in FIG. 4). The cap actuator 135 moves the flare cap 134 between the fully open position and the fully closed position. As shown in FIG. 4, the flare cap actuator 135 opens and closes the flare cap 134 by, for example, rotating or moving the flare cap 134 around the rotation shaft 136. Flare cap actuator 135 may use a chain drive or any other type of drive mechanism. The machine mechanism is connected to the flare cap 134 so as to move the flare cap 134 around the rotation shaft 136. Flare cap assembly 132 may also include a counterweight 137. The counterweight 137 is disposed on the opposite side of the rotation shaft 136 as viewed from the flare cap 134, and when the flare cap 134 moves around the rotation shaft 136, a part of the weight of the flare cap 134 is balanced or offset. ing. The counterweight 137 makes it possible to reduce the size or output of the actuator 135 while allowing the flare cap 134 to move or rotate between the open position and the closed position. In the open position, the upper part of the flare 130 (or the first combustion gas outlet 143) is open to the atmosphere, and in the closed position, the flare cap 134 is in the upper part of the flare 130 (or the first combustion gas). The outlet 143) is covered or substantially sealed. The flare cap 134 itself can be constructed of a high temperature resistant material (eg, stainless steel or carbon steel) and can be lined or insulated by a refractory material (eg, aluminum oxide and / or zirconium oxide) on the bottom. The refractory material is in direct contact with the hot flare gas when the flare cap 134 is in the closed position.

If desired, the flare 130 can include an adapter portion 138. The adapter portion 138 includes a first combustion gas outlet 143 and a second combustion gas outlet 141 upstream of the first combustion gas outlet 143. When the flare cap 130 is in the closed position, the combustion gas is sent through the second combustion gas outlet 141. The adapter part 138 may include a connector part 139. The connector part 139 connects the flare 130 (or the exhaust pipe) to the heat transfer part 117 using a 90-degree bent part or corner part. Other connector arrangements are possible. For example, the flare 130 and the heat transfer unit 117 may be connected at substantially any angle between 0 degrees and 180 degrees. In this case, the flare cap assembly 132 is attached to the top of the adapter portion 138 in the vicinity of the first combustion gas outlet 143.

As shown in FIGS. 3 and 4, the heat transfer assembly 117 includes a transfer tube 140. The transfer tube 140 connects to the inlet of the air pretreatment assembly 119 to the flare 130, and more particularly to the adapter portion 138 of the flare 130. The support member 142 takes the form of a vertical bar or pole and supports the heat transfer pipe 140 between the flare 130 and the air pretreatment assembly 119 at a predetermined height equal to or higher than the ground surface. The heat transfer pipe 140 is connected to the connector part 139 or the adapter part 138 at the second combustion gas outlet 141, and the transfer pipe is a fluid between the adapter part 138 and a second process (for example, a fluid concentration process). Form part of the passage. A typical reason for the need for the support member 142 is that the heat transfer pipe 140 is typically composed of a metal (eg, carbon steel or stainless steel) and is fire-resistant lining with a material (eg, aluminum oxide and / or zirconium oxide). Thus, the temperature of the gas moving from the flare 130 to the air pretreatment assembly 119 can be withstood. Therefore, the heat transfer pipe 140 is typically a heavy equipment. However, since flare 130 and air pretreatment assembly 119 and concentrator assembly 120 are positioned in close proximity to each other, it is generally possible to make heat transfer pipe 140 relatively short. This reduces the cost of the material used in the concentrator 110 and also reduces the amount of support structure required to support the weight of the heavy portion at a height higher than the surface of the concentrator 110. To do. As shown in FIG. 3, the heat transfer pipe 140 and the air pretreatment assembly 1119 form an upside down U-shaped structure.

The air pretreatment assembly 119 includes a vertical piping section 150 and an outside air valve (not explicitly shown in FIGS. 3 and 4). The outside air valve is disposed at an upper part of the vertical piping unit 150. The outside air valve (also referred to as a damper or bleed valve) forms a fluid path between the heat transfer pipe 140 (or air pretreatment assembly 119) and the outside air. The outside air valve operates to allow outside air to flow through the mesh bird screen 152 (typically wire or metal) into the air pretreatment assembly 119 and then mix with hot gas coming from the flare 130. If desired, the air pretreatment assembly 119 may include a permanent opening in the vicinity of the bleed valve that allows a certain amount of bleed air to enter the air pretreatment assembly 119. it can. Such bleed air may be desirable for reduced bleed valve size and safety reasons. If desired, a pressure blower (not shown) can be connected to the inlet side of the outside air valve to forcibly exhaust outside air through the outside air valve. When the pressure blower is mounted, the bird screen 152 and the permanent opening (when mounted) can be rearranged on the inlet side of the pressure blower. Control of the outside air or bleed valve is described in more detail herein below, which allows the gas from the flare 130 to cool to a more desirable temperature before entering the concentrator assembly 120. Is generally possible. The air pretreatment assembly 119 can be partially supported by a cross member 154 connected to the support member 142. These cross members 154 stabilize the air pretreatment assembly 119. The air pretreatment assembly 119 is also typically comprised of high-concentration carbon or stainless steel or other metals, and for increased energy efficiency and durability of the gases in this portion of the concentrator 110 against high temperatures. In addition, it can be fireproof lining. If desired, the vertical plumbing 150 can be extended to accommodate or accommodate different height flares, thereby allowing the liquid concentrator 110 to adapt to many different flares or different height flares. And improve the efficiency in assembling the concentrator when correcting some vertical and / or horizontal misalignment of the components. This concept is shown in more detail in FIG. As shown in FIG. 3, the vertical piping part 150 may include a first portion 150 </ b> A (shown by a dotted line). The first portion 150A is provided in the second portion 150B, whereby the length (height) of the vertical piping portion 150 can be adjusted.

Generally speaking, the air pretreatment assembly 119 mixes the outside air obtained through the outside air valve directly below the screen 152 with the hot gas flowing from the flare 130 through the heat transfer pipe 140 to achieve a desired temperature. Operate to obtain gas at the inlet of the concentrator assembly 120.

The liquid concentrator assembly 120 includes an introducer 156. The introduction portion 156 has a small cross section at the upper portion, and the lower portion of the piping portion 150 and the quencher 159 of the concentrator assembly 120 are engaged with each other at the upper portion. Concentrator assembly 120 also includes a first fluid inlet 160. The first fluid inlet 160 injects a new or untreated liquid to be concentrated (eg, landfill leachate) into the quencher 159. Although not shown in FIG. 3, the inlet 160 may include a coarse atomizer with a large nozzle. The coarse sprayer sprays the untreated liquid into the quencher 159. Since the liquid sprayed into the quencher 159 at this point in the system is not yet concentrated, it contains a large amount of water, and since the sprayer is a coarse sprayer, at the sprayer nozzle, within the liquid No fouling or embolism occurs due to small particles. As will be appreciated, the quencher 159 functions to rapidly reduce the temperature of the gas stream to (e.g., about 900 degrees Fahrenheit to 200 degrees Fahrenheit) while performing a high degree of evaporation of the liquid injected at the inlet 160. . If desired, although not explicitly shown in FIG. 3, a temperature sensor is provided at or near the outlet of the piping section 150 or in the quencher 159, and the position of the outside air valve is controlled using this temperature sensor. Thus, the temperature of the gas present at the inlet of the concentrator assembly 120 can be controlled.

As shown in FIGS. 3 and 5, the quencher 159 is connected to the liquid injection chamber. The liquid injection chamber is connected to a narrow part or a venturi part 162. The venturi portion 162 has a narrow cross section with respect to the quencher 159 and has a venturi plate 163 (illustrated by a dotted line) provided therein. The venturi plate 163 provides a narrow passage in the venturi portion 162, and a large pressure drop is generated between the inlet and the outlet of the venturi portion 162 due to the narrow passage. Due to this large pressure drop, gas turbulence and shearing force are generated in the quencher 159 and at the upper part or the inlet of the venturi part 162, and the gas flow exits the venturi part 162 at a high speed. The gas and liquid are sufficiently mixed in the part 162. The position of the venturi plate 163 can be controlled using a manual control rod 165 (shown in FIG. 5) or via an automatic positioner. The manual control rod 165 (shown in FIG. 5) is connected to the rotating shaft of the plate 163. The automatic positioner can be driven by an electric motor or a pneumatic cylinder (not shown in FIG. 5).

The recirculation pipe 166 extends around the opposite side of the inlet of the venturi section 162 and operates to inject partially concentrated (ie, recirculated) liquid into the venturi section 162 so that the liquid And / or avoid drying of particulates that pass through a plurality of fluid inlets disposed on one or more sides of the flow passage in the concentrator assembly 120. Although not explicitly shown in FIGS. 3 and 5, a plurality of pipes (for example, three pipes (for example, ½ inch in diameter)) are opposed to legs of the pipe 166 that partially surrounds the venturi portion 162. Can be extended from each part and through the wall to the interior of the venturi part 162. At this point, the liquid injected into the concentrator 110 is a recirculated liquid, so is it partially concentrated? Or, it is maintained at a certain equilibrium concentration and is more likely to clog the atomizer nozzle than a lower concentration liquid injected into the concentration inlet 160, so this liquid can be injected directly without using a sprayer. However, if desired, a flat plate shaped baffle may be placed in front of each opening of the 1/2 inch diameter pipe. Allows the liquid injected at this point in the system to collide with the baffle and be dispersed as smaller droplets in the concentrator assembly 120. In any event, the configuration of the recirculation system allows In the gas stream flowing through the concentrator assembly 120, the recirculated liquid is distributed or dispersed.

Both the hot gas and the liquid are turbulent and pass through the venturi section 162. As described above, the venturi section 162 has a movable venturi plate 163 disposed across the width of the concentrator assembly 120. Such a venturi 162 generates turbulent flow and completes a mixture of liquid and gas. As a result, the discontinuous liquid phase evaporates at high speed into a continuous gas phase. Due to the high evaporation resulting from the mixing effect obtained by the venturi section 162, the gas is substantially cooled in the concentrator assembly 120 and exits the venturi section 162 and enters the submerged bend 164 at high speed. In fact, the temperature of the gas liquid mixture at this point can be about 160 degrees Fahrenheit.

Similar to a typical flooded bend, a weir arrangement (not shown) within the lower portion of the flooded bend 164 maintains a level of partially or fully concentrated recirculated liquid therein. The recirculated liquid droplets mixed in the gas phase as a gas liquid mixture exit from the venturi section 162 at a high speed, and the gas liquid mixture is forcibly rotated by 90 degrees and flows into the fluid scrubber 122. Due to the centrifugal force generated at that time, it is projected outwardly onto the surface of the recirculated liquid held in the lower part of the submerged bend 164. A large number of droplets mixed in the gas phase collide with the surface of the recirculating liquid held in the lower part of the submerged bend 164, and then coalesce with the recirculated liquid. As a result, the submerged bend 164 The volume of recirculated liquid in the lower part of the fluid increases, and an equal amount of the recirculated liquid floods in the weir arrangement and flows into the sump 172 below the fluid scrubber 122 by gravity. Thus, the interaction between the gas liquid stream and the liquid in the submerged bend 164 removes droplets from the gas liquid stream, and the suspended particles in the gas liquid stream are located below the submerged bend 164. High-speed collisions are avoided, thereby avoiding the corrosion of the metal that forms the side walls located just below the height of the weir arrangement and below the flooded bend 164.

The gas liquid stream after exiting from the inundation bend 164 is still in a state of containing evaporating liquid and certain liquids and other particles, and this gas liquid stream passes through the fluid scrubber 122. The fluid scrubber 122 is a cross-flow fluid scrubber in this case. The fluid scrubber 122 includes various screens or filters that function to remove entrained liquids and other particles from the gas liquid stream. In one particular example, the crossflow scrubber 122 includes an initial coarse collision baffle 169 at the input. The initial coarse impact baffle 169 is designed to remove droplets that are 50-100 microns or larger in size. Thereafter, two removable filters in the form of chevrons 170 are placed on the fluid path in the fluid scrubber 122, and these chevrons 170 are liquids of smaller sizes (eg, 20-30 microns and less than 10 microns). It can be gradually sized or configured to remove drops. Of course, more or fewer filters or chevrons may be used.

Similar to a typical crossflow scrubber, the liquid obtained by the flood weir arrangement in the lower portion of the filters 169 and 170 and the flood bend 164 is gravity caused by a reservoir or sump 172 located at the lower portion of the fluid scrubber 122. Flows in. The sump 172 can hold, for example, approximately 200 gallons of liquid, thereby collecting concentrated fluid containing dissolved and suspended solids removed from the gas liquid stream and returning it back to the concentrator assembly 120. It functions as a reservoir for the source of circulating concentrated liquid, thereby allowing the liquid to be further processed in the manner described above for FIG. 1 and / or to avoid drying of particulates in the concentrator assembly 120. In one embodiment, sump 172 may include a sloped V-shaped lower portion 171. The V-shaped lower portion 171 has a V-shaped groove 175. The V-shaped groove portion 175 extends from the rear portion of the fluid scrubber 122 (the furthest away portion from the submerged bent portion 164) to the front portion of the fluid scrubber 122 (the closest portion to the submerged bent portion 164). The V-shaped groove 175 is inclined so that the lower portion of the V-shaped groove 175 is lower at the end of the fluid scrubber 122 closest to the submerged bend 164 than at the most distant portion from the submerged bend 164. In other words, the V-shaped lower portion 171 can be inclined with the outlet port 173 and / or the lowest point of the V-shaped lower portion 171 in the vicinity of the pump 182. Further, the cleaning circuit 177 (FIG. 9) allows concentrated fluid to be pumped from the sump 172 to the sprayer 179 in the crossflow scrubber 122. The sprayer 179 is intended to spray the liquid in the V-shaped lower part 171. Alternatively, the sprayer 179 can spray unconcentrated liquid or clean water on the V-shaped lower portion 171. The atomizer 179 sprays liquid regularly or constantly on the surface of the V-shaped lower portion 171 to clean the solids and avoids solid accumulation on the V-shaped lower portion 171 or the outlet port 173 and / or the pump 182. be able to. The V-shaped inclined lower portion 171 and the washing circuit 177 allow the liquid collected in the sump 172 to be continuously stirred and regenerated, thereby maintaining a relatively constant consistency, Keep the solid inside. If desired, the spray circuit 177 may be a separate circuit using a separate pump with an inlet in the sump 172, for example, using a pump 182 associated with a concentrated liquid recirculation circuit described below. It is also possible to spray the concentrated fluid from the sump 172 onto the V-shaped lower part 171.

As shown in FIG. 3, return line 180 and pump 182 operate to recirculate fluid removed from the gas liquid stream from sump 172 to concentrator 120, thereby providing a fluid or liquid recirculation circuit. To complete. Similarly, a pump 184 can be provided in the input line 186 to pump new or untreated liquid (eg, landfill leachate) to the input 160 of the concentrator assembly 120. In addition, one or more sprayers 185 are provided in the fluid scrubber 122 adjacent to the chevron 170, and the sprayers 185 periodically spray a portion of the clean water or the waste water feed onto the chevron 170 to provide the chevron 170. It can also be kept clean.

The concentrated liquid can also be removed from the lower portion of the fluid scrubber 122 via the outlet port 173 and can be further processed or disposed in the second recirculation circuit 181 in any suitable manner. Specifically, the concentrated liquid removed from the outlet port 173 contains a certain amount of suspended solids. The specific amount of suspended solids can preferably be separated from the liquid portion of the concentrated liquid and removed from the system using the second recirculation circuit 181. For example, the concentrated liquid removed from the outlet port 173 may pass through the second recirculation circuit 181 to one or more solid / liquid separation devices 183 (eg, precipitation tanks, vibrating screens, rotary vacuum filters, horizontal belt vacuum filters, belts). Press, filter press and / or liquid centrifuge). After separating the suspended solids and liquid portion of the concentrated wastewater by the solid / liquid separation device 183, the liquid portion of the concentrated wastewater is substantially removed along with the suspended particles, and then the concentrated wastewater is returned to the sump 172, Further processing takes place in the first recirculation circuit or the first recirculation circuit connected to the concentrator.

The gas exits the fluid scrubber 122 along with the liquid and suspended solids removed from the gas, exits the piping or duct at the rear of the fluid scrubber 122 (downstream of the chevron 170), and the draft fan of the exhaust assembly 124 The air flows out from 190 and is exhausted from the draft fan 190 to the outside air. In the outside air, the cooled high-temperature inlet gas is mixed with the evaporated water vapor. Of course, the induced draft fan motor 192 is connected to the fan 190 and causes the fan 190 to generate a negative pressure in the fluid scrubber 122 to eventually transfer the gas from the flare 130 to the transfer tube 140, the air pretreatment assembly 119 and the concentration. Aspirate through the vessel assembly 120. As described above with reference to FIG. 1, the draft fan 190 need only generate some negative pressure in the fluid scrubber 122, which ensures proper operation of the concentrator 110.

The speed of the draft fan 190 may vary depending on the device (eg, variable frequency drive) that operates to generate different levels of negative pressure within the fluid scrubber 122, and is therefore usually operable within a constant gas flow capacity. This can ensure complete gas flow from the flare 130. If the amount of gas generated from the flare 130 is insufficient, it may not always be possible to adjust the operation of the draft fan 190 to ensure an adequate pressure drop over the fluid scrubber 122 itself. is there. That is, for efficient and proper operation, the gas flowing in the fluid scrubber 122 needs to have a sufficient (minimum) flow rate at the input of the fluid scrubber 122. Typically, this requirement is controlled by maintaining at least a preset minimum pressure drop on the fluid scrubber 122. However, if the gas generated from the flare 130 has not reached at least the minimum level, the required pressure drop on the fluid scrubber 122 cannot be obtained even if the speed of the draft fan 190 increases.

To compensate for this situation, the cross flow scrubber 122 is designed to include a gas recirculation circuit. This gas recirculation circuit can be used to ensure that there is sufficient gas at the input of the fluid scrubber 122, thereby obtaining the required pressure drop on the fluid scrubber 122 in the system. It becomes possible. Specifically, the gas recirculation circuit includes a gas return line or return duct 196. The return duct 196 connects the high pressure side of the exhaust assembly 124 (eg, downstream of the draft fan 190) to the input of the fluid scrubber 122 (eg, the gas input of the fluid scrubber 122) and the baffle or control mechanism 198. The control mechanism 198 is disposed in the return duct 196 and operates to open and close the return duct 196, thereby fluidly connecting the high pressure side of the exhaust assembly 124 and the input of the fluid scrubber 122. In operation, if the amount of gas entering fluid scrubber 122 is not sufficient to obtain the required minimum pressure drop on fluid scrubber 122, baffle 198 (which may be, for example, a gas valve, damper, (E.g., a louvered damper) may be opened so that gas from the high pressure side of the exhaust assembly 124 (i.e., gas that has passed through the draft fan 190) returns to the input of the fluid scrubber 122. , Direct the gas. This operation makes it possible to obtain a sufficient amount of gas at the input of the fluid scrubber 122, whereby the required draft pressure on the fluid scrubber 122 can be obtained by operation of the draft fan 190.

FIG. 6 illustrates certain advantageous features of the compact liquid concentrator 110 of FIG. An advantageous feature is the form of a set of easily openable access doors 200. An easily openable access door 200 allows access to the interior of the concentrator 110 for cleaning and viewing purposes. In FIG. 6, an easily openable access door 200 is shown on one side of the fluid scrubber 122, but a similar set of doors can be provided on the other side of the fluid scrubber 122, and It is also possible to provide one door in front of the water-bending portion 164 as shown in FIG. As shown in FIG. 6, the easily accessible door 200 on the fluid scrubber 122 includes a door plate 202. The door plate 202 can be flat metal and is connected to the fluid scrubber 122 via two hinges 204, which can be pivoted on the hinges 204 to open and close. A plurality of quick release latches are disposed around the door plate 202 along with the pivot handle 206 and operate to hold the door plate 202 in the closed position and close the door 200 during operation of the fluid scrubber 122. In the embodiment shown in FIG. 6, eight quick release latches 206 are disposed around each door plate 202, but any other desired number of quick release latches 206 may be used.

FIG. 7 shows one of the doors 200 located at the open position. As will be appreciated, the door seat 208 is mounted away from the wall of the fluid scrubber 122 and the extension member 209 is disposed between the door seat 208 and the outer wall of the fluid scrubber 122. The gasket 210 may be constructed of rubber or other compressible material and may be disposed around the opening on the door seat 208. Similar gaskets may additionally or alternatively be provided around the inside of the door plate 202, which improves the sealing when the door 200 is in the closed position.

One of the quick release latches 206 is shown in more detail in FIG. The quick release latch 206 includes a handle 212 and a latch 214 (in this case, a U-shaped metal piece). The latch 214 is mounted on a swivel bar 216 disposed through the handle 212. The handle 212 is mounted on a further rotating shaft member 218. The rotary shaft member 218 is mounted on the outer wall of the door plate 202 via the mounting bracket 219. As handle 212 moves above and around further pivot member 218 (ie, from the position shown in FIG. 8), latch 214 moves toward the outer wall of fluid scrubber 112 (when door plate 202 is in the closed position). Thus, the latch 214 can be arranged on the side of the hook 220 in the direction away from the door plate 202. The hook 220 is attached on the extension member 209. Thereafter, when the handle 210 rotates in the opposite direction, the latch 214 is pulled firmly into the hook 220, thereby pulling the further pivot member 218 and thus the door plate 202 against the door seat 208. All the quick release latches 206 operate to secure the door plate 202 to the door seat 208 and the gasket 210 provides a firm fluid connection. Therefore, by closing these eight quick release latches 206 on the specific door 200 as shown in FIG. 6, it becomes possible to obtain a reliable and airtight mechanism for holding the door 200.

By using the door 200 that can be easily opened, a plate with holes is not required. In the case of such a holed plate, a large number of bolts extending from the outer wall of the concentrator are installed in the hole of the plate, and the nut on the bolt can be tightened to attract the plate to the concentrator wall. is necessary. Such a locking mechanism using nuts and bolts is often used in a fluid concentrator to gain access to the interior of the concentrator. Although such a fixing mechanism is extremely reliable, the operation of this configuration takes time and labor when the access panel is opened and closed. In this case, the high-speed opening door 200 using the quick release latch 206 of FIG. 6 can be used. Because the inside of the fluid scrubber 122 is in a negative pressure state and the pressure in the fluid scrubber 122 is lower than the outside air pressure, it is not necessary to close the access panel using complicated nuts and bolts. Because. Of course, as will be appreciated, the configuration of the door 200 allows the door 200 to be easily opened and closed with minimal manual labor and without the use of instruments, thereby allowing the structure within the fluid scrubber 122 (e.g., Access to the impact baffle 169 or the removable filter 170, or other part of the concentrator 110 on which the access door 200 is mounted, can be made fast and easy.

Referring again to FIG. 5, it is understood that an access door 200 that opens at a high speed is also provided in front of the water immersion bend 164 of the concentrator assembly 120. The access door 200 allows easy access into the flooded bend 164. However, since most elements of the concentrator 10 operate under negative pressure, a similar high speed opening access door can be provided in any desired portion of the fluid concentrator 110.

A compact fluid concentrator 110 is obtained by combining the features shown in FIGS. The fluid concentrator 110 utilizes the form of gas generated from the action of the landfill flare that burns the landfill gas. When there is no fluid concentrator 110, such waste heat is directly discharged to the outside air. Significantly, the concentrator 110 utilizes a minimal amount of the expensive high temperature resistant material required for piping and structural equipment required to utilize the hot gas exiting the flare 130. For example, the cost and weight of the fluid concentrator 110 are reduced by making the transfer tube 140 made of the most expensive material short and minimum length. Furthermore, since the size of the heat transfer pipe 140 is small, only a single support member 142 is sufficient, thereby further reducing the construction cost of the concentrator 110. In addition, since the air pretreatment assembly 119 is located directly on the fluid concentrator assembly 120, the gas flowing toward the ground within these portions may directly support these portions of the concentrator 110 with the ground. Or it can be supported by a skid supporting these members. Further, this configuration places the concentrator 110 in close proximity to the flare 130, thereby making the concentrator 110 more compact. Similarly, this configuration places the hot section of concentrator 110 (eg, the top of flare 130, heat transfer pipe 140 and air pretreatment assembly 119) at a remote location above the ground and without accidental human contact. This makes it a safer configuration. In fact, due to the rapid cooling that occurs in the venturi section 162 of the concentrator assembly 120, the venturi section 162, the submerged bend 164, and the fluid scrubber 122 (even if the gas exiting the flare 130 is 1800 degrees Fahrenheit). It is often cooled to the extent that it does not. Such fast cooling of the gas-liquid mixture allows the use of generally lower cost materials that are easier to make and corrosion resistant. Furthermore, the components downstream of the water immersion bend 164 (eg, fluid scrubber 122, induction draft fan 190, and exhaust 124) can be made from materials such as glass fiber.

The fluid concentrator 110 is also a concentrator that operates at a very high speed. Since the concentrator 110 is a direct contact type concentrator, there is no increase in accumulation, clogging, and fouling comparable to most other concentrators. Further, since the flare cap 134 can be controlled to open and close depending on whether the concentrator 110 is used or operated, the flare 130 can be used without interruption when the concentrator 110 is started or stopped. The landfill gas can be burned. More specifically, the flare cap 134 can be opened at a high speed at an arbitrary timing, so that the landfill gas can be easily burned by the flare 130 in the same manner as when the concentrator 110 is stopped. On the other hand, when the concentrator 110 is activated, the flare cap 134 can be closed at high speed, whereby the hot gas generated in the flare 130 is diverted to the concentrator 110 and concentrated without interrupting the operation of the flare 130. The device 110 can be activated. In any case, it is possible to start and stop the concentrator 110 based on the operation of the flare cap 134 and without interrupting the operation of the flare 130.

If desired, the amount of gas moving from the flare 130 to the concentrator 110 can be controlled by partially opening the flare cap 134 during operation of the concentrator 110. Combining this operation with the operation of the outside air valve can be useful in controlling the temperature at the inlet of the venturi 162.

Further, a compact configuration comprising an air pretreatment assembly 119, a concentrator assembly 120, and a fluid scrubber 122 allows the concentrator assembly 120 portion, the fluid scrubber 122, the traction fan 190, and at least the lower portion of the exhaust 124 to be in FIG. It can be permanently mounted (or connected to and supported by the skid or plate 230) on the skid or plate 230 as shown. The top of the concentrator assembly 120, the air pretreatment assembly 119 and the heat transfer pipe 140, and the top of the exhaust stack may be removed and stored on the skid or plate 230 during transport or placed in a separate truck. It may be transported. Since the lower part of the concentrator 110 can be mounted on a skid or plate, the concentrator 110 is easy to move and attach. In particular, when the concentrator 110 is set up, with the fluid scrubber 122, the flooded bend 164, and the tow fan 190 mounted on the skid 230, other confinement areas on the ground or where the concentrator 110 is assembled. By simply loading and unloading the skid 230, it can be loaded and unloaded at the site where the concentrator 110 is used. The venturi 162, quencher 159, and air pretreatment assembly 119 can then be placed and attached to the top of the flooded bend 164. Thereafter, the piping part 150 can be extended so as to match the height of the flare 130 to which the concentrator 110 is connected. In some cases, this extension may require that the flare cap assembly 132 be first attached to the existing flare 130. Thereafter, the heat transfer pipe 140 can be raised to an appropriate height and mounted between the flare 130 and the air pretreatment assembly 119 with the support member 142 in place. For a concentrator with a daily evaporation capacity of 10,000 to 30,000 gallons, the entire flare assembly 115 can be mounted on the same skid or plate 230 as the concentrator 120.

Because most pumps, fluid lines, sensors and electrical equipment are located on or connected to the fluid concentrator assembly 120, the fluid scrubber 122 or traction fan assembly 190, concentrating at a particular site Only the minimum piping, mechanical work, and electrical work are required in the field when setting the vessel 110. As such, the concentrator 110 can be installed and set up relatively easily at a particular site (and is relatively easy to disassemble and remove). In addition, since most of the components of the concentrator 110 are permanently attached to the skid 230, the concentrator 110 can be easily transported by truck or other transport vehicle, and also at a particular location (eg, landfill). Can be easily loaded and unloaded in the vicinity of the flare.

FIG. 9 is a schematic diagram of the control system 300. The control system 300 can be used to operate the concentrator 110 of FIG. As shown in FIG. 9, the control system 300 includes a controller 302. The controller 302 may be a digital signal processor type controller, such as a programmable logic controller (PLC) capable of performing ladder logic control, or any other type of controller. Of course, the controller 302 is connected to various components within the concentrator 110. Specifically, the controller 302 is connected to the flare cap drive motor 135. The flare cap drive motor 135 controls the opening / closing operation of the flare cap 134. The motor 135 can be set to control the flare cap 134 to move between the fully open position and the fully closed position. However, if desired, the controller 302 can be driven to open the flare cap 134 to any of a set of different controllable positions between the fully open position and the fully closed position. It is possible to control the motor 135. If desired, the motor 135 is continuously variable, which allows the flare cap 134 to be placed at any desired point between the fully open position and the fully closed position.

In addition, the controller 302 is connected to and controls the outdoor air inlet valve 306 located in the air pretreatment assembly 119 of FIG. 3 upstream of the venturi 162. Controller 302 can be used to control pumps 182 and 184. Pumps 182 and 184 control the injection volume of the new liquid to be treated and control the ratio between the injection volume and the recirculated liquid being processed in the concentrator 110. The controller 302 is operatively connectable to a sump level sensor 317 (eg, a float sensor), a non-contact sensor (eg, a radar or sonic unit, or a differential pressure cell). Controller 302 can use signals from sump level sensor 317 to control pumps 182 and 184 to maintain the concentrated fluid level in sump 172 at a predetermined or desired level. The controller 302 can be connected to the draft fan 190 so as to control the operation of the fan 190. The fan 190 can be a single speed fan, a variable speed fan or a fan whose speed can be controlled continuously. In one embodiment, the draft fan 190 is driven by a variable frequency motor so that the frequency of the motor is changed to control the speed of the draft fan 190. Further, the controller 302 is connected to the temperature sensor 308. The temperature sensor 308 is disposed, for example, at the inlet of the concentrator assembly 120 or the inlet of the venturi 162 and receives the temperature signal generated by the temperature sensor 308. Alternatively, the temperature sensor 308 may be provided downstream of the venturi unit 162, or a pressure sensor that generates a pressure signal may be provided in the temperature sensor 308.

In operation and, for example, when the concentrator 110 is activated, when the flare 130 is actually generated, thereby burning the landfill gas, the controller 302 first turns on the draft fan 190 to turn on the fluid scrubber 122 and the concentrator assembly. A negative pressure is generated in 120. Thereafter or simultaneously, controller 302 sends a signal to motor 135 to partially or completely close flare cap 134 to direct waste heat from flare 130 into transfer tube 140 and to air pretreatment assembly 119. Convert. Based on the temperature signal from the temperature sensor 308, the controller 302 may control the outside air valve 306 and / or flare cap actuator (typically by partially or completely closing the outside air valve 306), thereby Control the gas temperature at the inlet of the concentrator assembly 120. Generally speaking, the outside air valve 306 can be biased in a fully open position by a biasing element (eg, a spring) (ie, it can be normally open). The controller 302 begins to close the valve 306, thereby controlling the amount of outside air sent into the air pretreatment assembly 119 (due to negative pressure in the air pretreatment assembly 119), thereby causing the flare 130 to The ambient air and hot gas mixture are brought to the desired temperature. Further, if desired, the controller 302 can control the position of the flare cap 134 (any position between fully open and fully closed) and control the speed of the draft fan 190 to pre-treat air from the flare 130. The amount of gas entering the assembly 119 may be controlled. As will be appreciated, the amount of gas flowing through the concentrator 110 may need to be changed depending on the ambient temperature and humidity, the temperature of the flare gas, the amount of gas exiting the flare 130, and the like. Thus, the controller 302 may select one or any combination of the position of the outside air control valve 306, the flare cap 134, and the speed of the draft fan 190 based on the measured value of the temperature sensor 308 at the inlet of the concentrator assembly 120, for example. By controlling, the temperature and amount of gas passing through the concentrator assembly 120 may be controlled. The reason this feedback system is desirable is that in many cases the air generated from flare 130 is 1200-1800 degrees Fahrenheit, such temperatures are too hot, or the concentrator 110 is efficient and effective. This is because it is much higher than the temperature required for operation.

In any event, the controller 302 is also connected to a motor 310, as shown in FIG. The motor 310 controls the amount of turbulence generated in the concentrator assembly 120 by driving or controlling the position of the venturi plate 163 within the narrow portion of the concentrator assembly 120. In addition, the controller 302 controls the operation of the pumps 182 and 184 so that the recirculated liquid and the new waste liquid to be treated are sent from the pumps 182 and 184 to the input of the quencher 159 and the venturi unit 162 (and the ratio between them). ) Can be controlled. In one embodiment, the controller 302 can control the ratio between the recirculated fluid and the new fluid to be about 10: 1, so that new liquid is pumped from the pump 184 at a rate of 8 gallons per minute. When provided to input 160, recirculation pump 182 pumps 80 gallons per minute. Additionally or alternatively, the controller 302 may enter the concentrator (via pump 184) by maintaining a constant or predetermined level of concentrated liquid in the sump 172 using, for example, a level sensor 317. The flow of the new liquid to be treated can be controlled. Of course, the amount of liquid in the sump 172 depends on the concentration rate in the concentrator, the rate at which the concentrated liquid is pumped from the sump 172 through a second recirculation circuit, and the concentrated liquid present in the sump 172 in other cases. Of liquid from the second recirculation circuit to the sump 172 and liquid from the sump 172 for delivery to the concentrator via the first recirculation circuit. It depends on the pumping speed.

If desired, one or both of the outside air valve 306 and the flare cap 134 can be operated in a fail-safe open position, thereby causing a system failure (eg, a loss of control signal) or the concentrator 110 At the time of stop, the flare cap 134 and the outside air valve 306 are opened. In one case, the flare cap motor 135 may be spring biased or biased by a biasing element (eg, a spring) that opens the flare cap 134 or loses power to the motor 135. If broken, the flare cap 134 is opened. Alternatively, the biasing element may be a counterweight 137, or when the motor 135 loses power or a control signal, the flare cap 134 itself is a force applied from the counterweight 137. The flare cap 134 may be arranged so as to swing downward to the opening position. This action allows the flare cap 134 to be opened at a high speed either when power is lost or when the controller 302 opens the flare cap 134, thereby allowing hot gas in the flare 130 to be drawn from the top of the flare 130. It is possible to get out. Of course, other methods for opening the flare cap 134 upon loss of the control signal are available (eg, using a torsion spring on the axis of rotation 136 of the flare cap 134, pressurizing the cylinder to cause the flare cap 134 to open. Flare cap 134 opening upon loss of control signal due to loss of pressure in a closing hydraulic or pressurized air system).

Thus, as will be appreciated from the above description, the flare cap 134 and the outside air valve 306 cooperate to protect the design material used in the concentrator 110. This is because the flare cap and the air valve 306 are automatically opened each time the system is shut down, so that the hot air generated in the flare 130 is removed from the process while quickly taking in the outside air and cooling the process. It is because it insulates.

Further, in a similar manner, the external air valve 306 is configured to be spring-biased or otherwise open when the concentrator 110 is stopped or the signal to the valve 306 is lost. This action quickly cools the air pretreatment assembly 119 and the concentrator assembly 120 when the flare cap 134 is open. Further, since the outside air valve 306 and the flare cap 134 are opened at high speed, the controller 302 can stop the concentrator 110 at high speed without having to stop or execute the operation of the flare 130.

Further, as shown in FIG. 9, the controller 302 may be connected to a venturi plate motor 310 or other actuator that moves or operates the angle at which the venturi plate 163 is provided within the venturi portion 162. Using motor 310, controller 302 changes the angle of venturi plate 163 to change the gas flow through concentrator assembly 120, thereby changing the nature of the gas turbulence in concentrator assembly 120. As a result, the mixing of the liquid and gas inside can be improved, and the liquid can be evaporated more completely. In this case, the controller 302 can optimize the concentration of the wastewater being processed by associating the speeds of the pumps 182 and 184 with the operation of the venturi plate 163. In this way, as will be appreciated, the controller 302 can determine the position of the venturi plate 163, the operation of the flare cap 134, the outside air or bleed valve without completely drying the waste water to avoid drying of particulates. By coordinating the position of 306 and the speed of the introduction fan 190, the wastewater concentration (turbulent mixing) can be maximized. The controller 302 can arrange the venturi plate 163 using the pressure input from the pressure sensor. Of course, the venturi plate 163 may be manually controlled or automatically controlled.

Controller 302 is also connected to motor 312. The motor 312 controls the operation of the damper 198 in the gas recirculation circuit of the fluid scrubber 122. For example, based on signals from pressure sensors 313 and 315 located at the gas inlet and gas outlet of the fluid scrubber 122, the controller 302 causes the motor 312 or other type of actuator to move the damper 198 from the closed position to the open position or partially. Move to the opening position. The controller 302 controls the damper 198 to forcibly flow the gas into the fluid scrubber inlet from the high pressure side of the exhaust part 124 (downstream of the induction draft fan 190), and thereby between the two pressure sensors 313 and 315. A predetermined minimum pressure difference can be maintained. By maintaining this minimum pressure differential, proper operation of the fluid scrubber 122 is assured. Of course, the damper 198 can be manually controlled instead of or electrically controlled.

Thus, as will be appreciated from the above description, the controller 302 may execute one or more on / off control loops used to start or stop the concentrator 110 without affecting the operation of the flare 130. it can. For example, the controller 302 may control the flare cap control loop that opens and closes the flare cap 134, the bleed valve control loop that begins to open or close the outside air valve 306, and the draft fan 190 that is based on activation or deactivation of the concentrator 110. An induced draft fan control loop that can be activated or deactivated can be performed. Further, in operation, the controller 302 can execute one or more online control loops. The one or more on-line control loops can improve or optimize the concentration by controlling various elements of the concentrator 110 individually or in conjunction with another element. In performing these online control loops, the controller 302 may determine the speed of the draft fan 190, the position or angle of the venturi plate 163, the position of the flare cap 134 and / or the signal based on the signals from the temperature and pressure sensors. By controlling the position of the outside air valve 306, the fluid flow through the concentrator 110 and / or the temperature of the air at the inlet of the concentrator assembly 120 can be controlled. Further, the controller 302 can maintain the performance of the concentration process at a steady state by controlling the pumps 184 and 182. Pumps 184 and 182 pump new fluid and recirculation fluid to be concentrated into concentrator assembly 120. Further, the controller 302 can execute a pressure control loop. In the pressure control loop, the position of the damper 198 is controlled to ensure proper operation of the fluid scrubber 122. Of course, although controller 302 is illustrated in FIG. 9 as a single controller device that performs these various control loops, controller 302 may be implemented as a plurality of different control devices, eg, using a plurality of different PLCs. Is also possible.

As will be appreciated, the concentrator 110 described herein utilizes hot exhaust gas directly in the process after sufficient treatment of the hot exhaust gas to meet emission standards, thereby providing simplicity and reliability. There is an uninterrupted separation of the operational requirements of a process that generates waste heat from a process that uses waste heat in an effective and effective manner.

In addition to being a key element of the concentrator 110 during operation of the concentrator 110, the automated or manually actuated flare cap 134 described herein can be utilized standalone. This can serve as rain avoidance for the flare or flare and concentrator combination when the flare is idle. When the flare cap 134 is closed, the interior of the metal shell of the flare 130, along with the refractory elements, burner elements and other critical elements of the flare assembly 115, and the heat transfer assembly 117, is generally associated with corrosion and exposure to components. Protects against mechanical degradation. In this case, when the flare 130 is in an idle state, the controller 302 operates the flare cap motor 135 to hold the flare cap 134 in a fully open or partially closed state. In addition to the use of the flare cap 134 that automatically closes when the flare 130 is stopped or the flare cap 134 that automatically opens when the flare 130 is ignited, a small burner (for example, a normal ignition burner) is attached to the inside of the flare 130. Thus, this small burner can be used when the flare 130 is stopped when the flare cap 134 is closed. Since the inside of the flare 130 is maintained by using such a small burner, it is possible to further protect the deterioration of the flare component due to moisture. As an example of a stand-alone flare that can use the flare cap 134 described in this specification in a stand-alone manner, a factory that is supplied with fuel from landfill gas is offline by installing a standby flare in the landfill. It becomes possible to ensure the gas control at a certain time.

Although the liquid concentrator 110 has been described above as being connected to the landfill flare so that the waste heat generated in the landfill flare can be used, the liquid concentrator 110 can be easily connected to other waste heat sources. It is. For example, in the case of the concentrator 110 shown in FIG. 10, it is connected to the exhaust pipe of the combustion engine factory 400 and has been modified to perform liquid concentration using waste heat from the engine exhaust. In one embodiment, the engine in the factory 400 operates with landfill gas to generate electricity, but the concentrator 110 may be other types of engines (eg, other types of combustion engines (eg, gasoline, diesel fuel). It is also possible to connect so as to operate by exhausting from the one that operates by, for example.

Referring to FIG. 10, exhaust generated in an engine (not shown) in factory 400 is sent to muffler 402 outside factory 400, and enters muffler 404 from muffler 402. A combustion gas exhaust cylinder cap 406 is provided on the upper part of the combustion gas exhaust cylinder 404. The cap 406 is essentially counterweighted so as to cover the exhaust stack 404 when there is no exhaust exiting the stack 404, but when exhaust exits the stack 404, it is easily caused by exhaust pressure. It can be pushed up. In this case, the Y connector provided in the exhaust tube 404 operates to connect the stack 404 to the transfer pipe 408. The transfer pipe 408 moves the exhaust gas (waste heat source) from the engine to the expansion unit 410. The extension 410 meshes with the quencher 159 of the concentrator 110 and sends exhaust gas from the engine directly to the concentrator assembly 120 of the concentrator 110. When engine exhaust is used as a waste heat source, it is often unnecessary to provide an air bleed valve upstream of the concentrator portion 120. This is because the exhaust gas leaving the engine is typically less than 900 degrees Fahrenheit and does not need to be significantly cooled before entering the quencher 159. The rest of the concentrator 110 is the same as that described above with reference to FIGS. Thus, it will be appreciated that the liquid concentrator 110 can be readily adapted to utilize a variety of different waste heat sources without requiring significant modification.

In general, when controlling the liquid concentrator 110 of FIG. 10, the controller turns on the draft fan 190 while the engine in the factory 400 is operating. The controller increases the speed of the draft fan 190 from the minimum speed until most or all of the exhaust in the stack 404 enters the transfer tube 408 (instead of leaving the top of the stack 404). It is easy to detect this operating point. This operating point is reached when the cap 406 first returns to the top of the stack 404 as the speed of the draft fan 190 increases. By avoiding the speed of the induced draft fan 190 from exceeding this operating point, the negative pressure in the concentrator 110 is prevented from becoming higher than necessary, so that the back pressure due to the operation of the concentrator 110 is reduced. It is important that it does not change (specifically, an undesirable level of suction does not occur in the engine within the factory 400). Any change in back pressure or the occurrence of suction in the exhaust stack 404 is undesirable because it adversely affects the combustion operation of the engine. In one embodiment, a controller (not shown in FIG. 10) (eg, a PLC) may use a pressure transducer. This pressure transducer is mounted in the stack 404 adjacent to the position of the cap 406 to continuously monitor the pressure at this position. The controller then signals a variable frequency drive on the induced draft fan 190 to control the speed of the induced draft fan 190 to maintain the pressure at the desired set point, thereby reducing unwanted back pressure or suction. Prevent it from occurring on the engine.

11 and 12 are a side cross-sectional view and a horizontal cross-sectional view of another embodiment of the liquid concentrator 500. The concentrator 500 is generally oriented in the vertical direction. However, the concentrator 500 shown in FIG. 11 may be oriented generally horizontally or may be oriented generally vertically depending on the particular constraints in a particular application. For example, if the concentrator is loaded onto a truck, the concentrator should be oriented generally horizontally so that the truck loaded with the concentrator can pass under the bridge during transportation between sites. Can do. The liquid concentrator 500 has a gas inlet 520 and a gas outlet 522. A flow passage 524 connects the gas inlet 520 to the gas outlet 522. The flow passage 524 has a narrow portion 526. In the narrow portion 526, the gas passing through the flow passage 524 is accelerated. In front of the narrow portion 526, liquid is injected from the liquid inlet 530 into the gas stream. In contrast to the embodiment of FIG. 1, the narrow portion 526 of the embodiment of FIG. 11 directs the gas liquid mixture into the cyclone chamber 551. The cyclone chamber 551 improves the mixing of the gas and liquid while providing the function of the demister in FIG. The gas-liquid mixture enters the cyclone chamber 551 in a tangential direction (see FIG. 12) and then passes through the cyclone chamber 551 in a cyclone manner to the liquid outlet region 554. Cyclone circulation is facilitated by a hollow cylinder 556 provided in the cyclone chamber 551. The hollow cylinder 556 guides the gas to the gas outlet 522. The hollow cylinder 556 presents a physical barrier and maintains cyclone circulation within the cyclone chamber 551 (including the liquid outlet region 554).

As the gas liquid mixture passes through the narrow portion 526 of the flow passage 524 and circulates in the cyclone chamber 551, a portion of the liquid evaporates and is absorbed by the gas. Further, the movement of the mixed droplets in the gas to the side wall 552 of the cyclone chamber 551 is accelerated by centrifugal force, and the mixed droplets coalesce on the side wall 552 to form a film on the side wall 552. At the same time, the centripetal force generated by the inlet fan 550 collects the demisted gas flow at the inlet 560 of the cylinder 556 and directs this flow to the gas outlet 522. Thus, the cyclone chamber 551 functions as both a mixing chamber and a demisting chamber. Due to the synergistic effect of gravity and cyclone motion toward the liquid outlet region 554 in the cyclone chamber 551, when the liquid film flows to the liquid outlet region 554 of the chamber, the continuous circulation of gas in the cyclone chamber 551 causes the A part of the liquid film further evaporates. When the liquid film reaches the liquid outlet region 554 of the cyclone chamber 551, the liquid is directed through the recirculation circuit 542. In this way, the liquid is recirculated through the concentrator 500 until a desired level of concentration is reached. When the concentrated slurry reaches the desired concentration, a portion of the concentrated slurry can be discharged through the extraction port 546 (this is referred to as blowdown). A new liquid is then added to the circuit 542 through the new liquid inlet 544 at a rate equal to the sum of the evaporation rate and the slurry discharge rate through the extraction port 546.

As the gas circulates in the cyclone chamber 551, the gas is purified to remove entrained droplets, after which the gas is drawn by the introduction fan 550 toward the liquid discharge region 554 of the cyclone chamber 551, Move to entrance 560. The purified gas then travels through the hollow cylinder 556 and eventually exits through the gas outlet 522 to the atmosphere or further processing (eg, oxidation in flare).

FIG. 13 is a schematic diagram of a dispersion type liquid concentrator 600. Distributed liquid concentrator 600 is located in many types of waste heat sources (locations that are difficult to access (eg, on the side of a building, in the middle of various other equipment, away from roads or other access points)) Configured for use with a waste heat source). Although the liquid concentrator 600 is described herein as being used for processing or concentrating leachate (eg, leachate collected from a landfill), the liquid concentrator 600 is intended for other types of liquid concentrating applications. Can also be used, or can include many arbitrary types of wastewater.

Generally speaking, the liquid concentrator 600 includes a gas inlet 620, a gas outlet or gas outlet 622, a flow passage 624 connecting the gas inlet 620 to the gas outlet 622, and a liquid recirculation system 625. The concentrator portion has a flow passage 624. The flow passage 624 includes a quencher unit 659, a venturi unit 626, and a blower or traction fan 650. The quencher 659 includes a gas inlet 620 and a fluid inlet 630. The venturi unit 626 is provided downstream of the quencher unit 659. A blower or traction fan 650 is connected downstream of the venturi section 626. The fan 650 and the submerged bend 654 connect the gas outlet of the concentrator part (for example, the outlet of the venturi part 626) to the pipe part 652. In this case, the flooded bent portion 654 forms a 90-degree corner in the flow passage 624. However, the water immersion bend 654 can form a corner less than 90 degrees or greater than 90 degrees if desired. The piping section 652 is connected to a demister (in this case, illustrated in the form of a cross flow scrubber 634). The cross flow scrubber 634 is connected to a stack 622 A having a gas outlet 622.

The recirculation system 625 includes a sump 636 and a recirculation or recycle pump 640. The sump 636 is connected to the liquid outlet of the cross flow scrubber 634. The recirculation or recycle pump 640 is connected between the sump 636 and the pipe portion 642. The piping portion 642 delivers the recirculated fluid to the fluid inlet 630. Process fluid feed 644 also sends leachate or other liquid to be processed (eg, concentrate) to fluid inlet 630 and to quencher 659. The recirculation system 625 also includes a liquid take-off 646. Liquid take-off 646 is connected to piping section 642. The piping unit 642 sends a part of the recycled fluid (or concentrated fluid) to a storage, precipitation, and recycling tank 649. The heavier or more concentrated portion of the liquid in the settling tank 649, the more the liquid will settle as sludge in the lower part of the tank 649, which will be removed and transported and landfilled in concentrated form. Liquid with less concentrated portion of the liquid in tank 649 is returned to sump 636 where it is reprocessed and further concentrated to ensure that an adequate supply of liquid is always available at liquid inlet 630. Avoid drying the particles. If the microparticles are dried, it can cause a reduction in the ratio between the process fluid and the hot gas volume.

In operation, the quencher 659 mixes the fluid delivered from the liquid inlet 630 with a gas containing waste heat collected from a stack 629 associated with, for example, an engine muffler and an internal combustion engine (not shown). The liquid from the fluid inlet 630 can be, for example, a leachate to be processed or concentrated. As shown in FIG. 13, the quencher 659 is connected in the vertical direction above the venturi 626. The venturi portion 626 has a narrow portion. The narrow portion accelerates the flow of gas and liquid through a portion of the fluid flow passage 624 just downstream of the venturi 626 and just upstream of the fan 650. Of course, the fan 650 operates to generate a low pressure region immediately downstream of the venturi section 626, thereby drawing gas from the stack 629 through the venturi section 626 and the submerged bend 654 to mix the gas and liquid. .

As described above, the quencher unit 659 can receive the hot exhaust gas from the engine exhaust pipe 629 and can be directly connected to any desired portion of the exhaust pipe 629. In the illustrated embodiment, the engine exhaust 629 is attached to the outside of the building 631. Building 631 houses one or more generators. The one or more generators generate electricity using landfill gas as fuel. In this case, the quencher 659 can be directly connected to a condensate take-off (eg, a weep leg) associated with the stack 629 (ie, the lower portion of the exhaust stack 629). Here, the quencher portion 659 can be directly attached to the lower side of the stack 629 or in the vicinity thereof, so that it requires only a few inches or at most a few feet of expensive high-temperature piping material for connecting the two. However, if desired, the quencher portion 659 can be coupled to any other portion of the exhaust stack 629 (eg, the top or middle portion of the stack 629) via a suitable bend or take-off.

As described above, the liquid inlet 630 injects the liquid to be evaporated (for example, landfill leachate) into the flow passage 624 through the quencher 659. If desired, the liquid inlet 630 can include a replaceable nozzle. The replaceable nozzle sprays the liquid into the quencher 659. The liquid inlet 630 can introduce the liquid in any direction from a vertical direction to a horizontal direction with respect to the gas flow as the gas moves through the flow passage 624, regardless of whether or not a nozzle is provided. . Further, as the gas (and waste heat therein) and liquid pass through the venturi 626, turbulence is accelerated according to the venturi principle, whereby in the flow passage 624 immediately downstream of the venturi 626, the Gas and liquid are thoroughly mixed. As a result of this turbulent mixing, part of the liquid evaporates at high speed and becomes part of the gas stream. In this evaporation, a large amount of heat energy is consumed in the waste heat. This is because the latent heat exiting the concentrator system 600 as water evaporates in the exhaust gas.

After exiting the narrow portion of the venturi 626, the gas / liquid mixture passes through the submerged bend 654. In the flooded bend 654, the flow passage 624 is bent at an angle of 90 degrees, thereby changing the vertical flow to the horizontal flow. The gas / liquid mixture passes through the fan 650 and then enters the high pressure region downstream of the fan 650. This high pressure region exists in the piping portion 652. There are at least two reasons why it may be desirable to use a flood bend 654 at this point in the system. First, the presence of liquid at the bottom of the flooded bend 654 reduces corrosion at the turning point of the flow passage 624. Such corrosion is due to suspended particles in the gas / liquid mixture that flow at high speed through the 90 degree corners and impinge directly on the lower surface of the conventional bend where the submerged bend 654 is not used. Often occur. The liquid in the lower part of the submerged bend 654 absorbs energy in these particles, thereby avoiding corrosion on the lower surface of the submerged bend 654. In addition, when the mixture reaches the inundation bend 654, the droplets still remaining in the gas / liquid mixture collide with the liquid so that the droplets can be more easily collected and removed from the flow stream. Can do. That is, the liquid below the submerged bend 654 operates to collect droplets that collide with the liquid. This is because the droplets in the flow stream can be more easily retained when these suspended droplets are in contact with the liquid. Thus, for example, a submerged bend 654 that may have a liquid take-off (not shown) connected to the recirculation circuit 625 is a portion of the process fluid droplets and concentrate from the gas / liquid mixture emerging from the venturi 626. Works to remove.

Importantly, the gas / liquid mixture reaches the adiabatic saturation point at high speed while passing through the venturi 626. The adiabatic saturation point is much lower than the adiabatic saturation point of the gas exiting the stack 629. For example, the gas exiting the stack 629 can be about 900 to about 1800 degrees Fahrenheit, but the gas / liquid mixture in the entire portion of the concentrator system 600 downstream of the venturi 626 is typically about 150 degrees Fahrenheit. It is 190 degrees. However, this temperature may be higher or lower than these values based on the operating parameters of the system. As a result, the portion of the concentrator system 600 downstream of the venturi 626 need not be composed of high temperature resistant material, and no heat insulation is required in the portion of the concentrator system 600 or the inlet hot gas In the case where heat insulation is used for the purpose of using a larger amount of waste heat, the heat insulation becomes unnecessary to the extent necessary for transporting a higher temperature gas. Further, the portion of the concentrator system 600 downstream of the venturi 626 is placed in an area (eg, an area along the ground that contacts humans) without great risk or with minimal external protection. Specifically, the portion of the concentrator system 600 downstream of the venturi section 626 can be constructed of glass fiber and requires no or minimal insulation. Importantly, the gas / liquid stream is within the portion of the concentrator system 600 downstream of the venturi 626 over a relatively long distance while maintaining its internal gas / liquid mixture in the vicinity of the adiabatic saturation point. It can flow, thereby allowing the flow stream to be easily transported from the piping 652 to a more accessible location in the direction away from the building 631. In this more easily accessible location, other equipment associated with the concentrator 600 can be conveniently placed. Specifically, the length of the piping portion 652 can be 20 feet, 40 feet or more while maintaining the flow inside the piping portion 652 in the vicinity of the adiabatic saturation point. Of course, these lengths can be longer or shorter based on the ambient temperature, piping type, thermal insulation utilized, and the like. Further, since the piping portion 652 is disposed on the high pressure side of the fan 650, the concentrate can be removed from the stream more easily. In the exemplary embodiment of FIG. 13, plumbing 652 passes through an air cooler associated with the engine in building 631 or is shown below the air cooler. However, the air cooler in FIG. 13 is only an example of the types of obstacles that can be placed in the vicinity of the building 631, and all the components of the concentrator 600 are in the vicinity of the waste heat source (in this case, the stack 629). It becomes a problem when arranging to. Other obstacles include other equipment, plants such as trees, other buildings, roads or areas that are not accessible due to lack of easy access points.

In any event, tubing 652 delivers a gas / liquid stream near the adiabatic saturation point to demister 634. The demister 634 can be, for example, a cross flow scrubber. The demister 634 operates to remove entrained droplets from the gas / liquid stream. The removed liquid collects in sump 636 and directs the liquid to pump 640. The pump 640 returns the liquid to the liquid inlet 630 through the return pipe 642 of the recirculation circuit 625. In this way, the obtained liquid can be further reduced by evaporation to the desired concentration and / or recycled to prevent drying of the microparticles. A new liquid to be concentrated is input through a new liquid inlet 644. The rate at which new liquid is input into the recirculation circuit 625 includes the rate of liquid evaporation as the gas liquid mixture flows through the flow passage 624 and the rate of liquid or sludge extracted from the settling tank 649 (this sludge is (Assuming the material in the settling tank 649 remaining at a certain level). Specifically, a portion of the liquid can be withdrawn through the extraction port 646 when the liquid in the recirculation circuit 625 reaches the desired concentration. The liquid portion withdrawn from the extraction port 646 can be sent to a storage and settling tank 649. In the storage and settling tank 649, the concentrated liquid precipitates and separates into components (eg, liquid and semi-solid portions). This semi-solid portion can be withdrawn from the tank 649 or further processed.

As described above, the fan 650 draws gas through part of the flow passage 624 under negative pressure and pushes gas through part of the flow passage 624 under positive pressure. The quencher unit 659, the venturi unit 626, and the fan 650 can be attached to the building 631 by any kind of connection device, and are arranged in the vicinity of the waste heat source as shown in FIG. However, the demister 634, the gas outlet 622, and the settling tank 649 may be disposed at a position (for example, a position where access is easy) at some distance from the quencher 659, the venturi 626, and the fan 650. In one embodiment, demister 634 and gas outlet 622 and settling tank 649 can be mounted on a movable platform (eg, a pallet or trailer bed).

FIGS. 14-16 illustrate another embodiment of a liquid concentrator 700. The liquid concentrator 700 can be mounted on a pallet or trailer bed. In one embodiment, some of the components of the concentrator 700 can be left on the bed and used for concentration activities. Other of these components can also be removed and installed in the vicinity of the waste heat source, for example, as shown in the embodiment of FIG. The liquid concentrator 700 has a gas inlet 720 and a gas outlet 722. A flow passage 724 connects the gas inlet 720 to the gas outlet 722. The flow passage 724 has a narrow or venturi 726. In the venturi 726, the gas accelerates through the flow passage 724. Gas is drawn into the quencher 759 by an introduction fan (not shown). Liquid is injected from the liquid inlet 730 into the gas stream in the quencher 759. The bend 733 directs gas from the venturi 726 into the demister (or crossflow scrubber) 734. After leaving the demister 734, the gas is directed through the stack 723 to the gas outlet 722. Of course, as noted above, some of these components may be removed from the bed and attached in the vicinity of the waste heat source, while other components (eg, demister 734, stack 723, and gas outlet 722) are mounted on the bed. You may leave it in.

As the gas-liquid mixture passes through the venturi 726 of the flow passage 724, a portion of the liquid evaporates and is absorbed by the gas, so that latent heat exits the concentrator system 700 as water vapor in the exhaust gas. When it goes, most of the heat energy in the waste heat is consumed.

In the embodiment shown in FIGS. 14-16, the components of the liquid concentrator 700 can be disassembled and attached to a transport pallet or trailer skid. For example, the quench portion 759 and the venturi portion 726 can be removed from the bent portion 733 as indicated by a broken line in FIG. Similarly, the stack 723 can be removed from the introduction fan 750 as indicated by the dashed line in FIG. The bend 733, the demister 734 and the introduction fan 750 can be fixed on the pallet or trailer skid 799 as a unit. Stack 723 can be separately secured to pallet or trailer skid 799. Quench 759 and venturi 726 may also be secured to the pallet or trailer skid 799 or may be shipped separately. Thus, by making the liquid concentrator 700 into a segmented structure, the liquid concentrator 700 can be easily transported.

The device and process embodiments described above can be easily modified to accommodate removal of contaminants from the wastewater being concentrated and the exhaust gas used to concentrate the wastewater. Such modifications are considered particularly advantageous when emissions from pollutants to be removed are typically regulated by government agencies. Examples of such pollutants include sulfur oxide (SOx) and ammonia (NH3) that are generally present in exhaust gas generated by landfill gas combustion. In the following, possible modifications in the embodiments of devices and processes as described above to be able to accommodate SOx and NH3 removal will be described. However, the following description is not intended to be limited to the removal of only these contaminants.

SOx removal

Hydrogen sulfide (H2S) is a known toxic gas and is generated due to bacterial degradation (chemical reduction) of compounds containing sulfur, sulfite and sulfate present in waste disposed in landfills. obtain. The H ₂ S thus formed coalesces with other gases generated by all forms of bacterial action performed for landfill gas formation in the landfill. In general, the greater the amount of waste containing sulfur, sulfite and sulfate, the greater the amount of hydrogen sulfide expected. For example, a landfill may have a certain amount of sulfate from a source of calcium sulfate (eg, gypsum wallboard material), such material being 10,000 (parts per million (ppm)) (weight basis) ) The above H ₂ S is generated in landfill gas. Hydrogen sulfide is part of a landfill gas that is burned, for example, in a landfill gas flare as described herein. The H ₂ S is combusted in a gas torch, Advantageous reason Doing reciprocation of the engine or turbine, H ₂ S is converted to sulfur oxides (SOx), thereby, landfill for H ₂ S removal This is because expensive pretreatment of ground gas is avoided. However, in some countries, sulfur oxides can be regulated air pollutants. The H ₂ S as a further advantage due to the combustion in a flare, since the heating value of the flare exhaust gas is increased by H ₂ S, can be concentrated landfill leachate by utilizing this heat value increases, this Therefore, the total amount of required fuel can be reduced.

Wet scrubbers are commonly used to remove SOx from exhaust gases generated due to the combustion of fuels containing sulfur compounds containing H ₂ S. An example of such a scrubber is a spray / packed tower. In the spray / packing tower, contact (wet) alkaline material (eg, sodium hydroxide or lime (CaCO 3) solution or slurry) is directly contacted (wet) with the exhaust gas to “scrub” SOx from the gas. (Ie remove). In the context of the waste water concentrator described herein, the principle of wet scrub can be utilized.

A sufficient amount of alkaline substance of known concentration sufficient to react with the SOx present in the exhaust gas can be added to the wastewater feed, and this material can be added to sodium sulfite and sodium sulfate (where the alkali is NaOH) and Convert to calcium sulfate (CaSO4) (where the alkali is lime). The formed sodium sulfite / sulfate and calcium sulfate salts are removed from the process as part of the liquid concentrate. Finally, the sodium sulfite / sulfate and calcium sulfate may be placed in a chemical waste treatment facility, or the sulfite / sulfate may be recycled into the landfill gas as H ₂ S. May be converted to a higher capacity solid stream (eg, 100% solids) and placed in a special dedicated cell at the landfill. The volume of residue (typically a very thin aqueous waste stream) generated from landfill leachate is often less than 3% of the supply volume, so the amount of sulfite / sulfate is Increasingly, transportation costs and landfill or construction costs in off-site chemical waste treatment facilities and the cost of operating special landfill cells containing 100% solids are the cost of scrubbing combustion gas emissions or (combustion Compared to the cost of removing hydrogen sulfide prior to combustion, without using the waste heat from the process as a primary energy source for the treatment of wastewater (eg leachate) should be a very economical amount .

Thus, by using dual purpose in a wastewater treatment system, we recognize that the upper limit of SOx emissions from factories fueled by flare (s) or landfill gas is exceeded. Landfill owners can benefit greatly. To provide a concentrator that provides both a concentrating mode and a scrub mode, a metering system (eg, a pump operably connected to the controller of the concentrator) and a supply for the selected alkaline agent used for scrubbing. It is only necessary to add a tank. Similarly, in an operational change to monitor the addition of the SOx removal stage to the enrichment process, a simple on-site analytical test is performed to determine the level of hydrogen sulfide in the landfill gas and the sulfuric acid in the concentrate generated in the process. The system is not that complicated because it only has to monitor the amount of salt.

Referring again to FIGS. 3 and 10, the concentrator portion 120 may include a cautery (or alkali) inlet 187. The inlet 187 is connected by a supply line 189 to a supply of cautery (or alkaline) material 193 (eg, sodium hydroxide or lime). The pump 191 can pressurize the supply line 189 with the cautery or alkaline material from the supply of cautery or alkaline material 193 so that the cautery or alkaline material is concentrated in the concentrator (eg, in the vicinity of the venturi 162). It is injected into portion 120 and mixed with flare 130 or exhaust gas from the generator. In other embodiments, the cauterizer or alkaline material can be mixed with the leachate in leachate input line 186 and then sent to the concentrator portion 120. Regardless of whether the cautery or alkaline material is sent to the concentrator portion 120, the cautery or alkaline material is mixed at high speed with the leachate and the exhaust gas in the concentrator portion 120 as described above. The After mixing, the cautery agent or alkaline substance reacts with the sulfur oxide, thereby converting the sulfur oxide into sodium sulfate and sodium sulfite or calcium sulfate as described above. After conversion, the sodium sulfate, sodium sulfite and / or calcium sulfate immediately enters a liquid phase and remains dissolved or precipitated from the gas / liquid mixture in the concentrator portion 120. In this manner, sulfur initially in the form of H ₂ S in the landfill gas phase is converted into a liquid phase as sodium sulfate / sulfite and calcium sulfate, and finally the concentrated leachate in the sump 172 of the demister section 122. Can be obtained with and withdrawn with concentrated leachate for later landfill. As shown in FIG. 9, the controller 302 can be operatively connected to a pump 191 to control the rate at which cautery or alkaline material is measured into the concentrator portion 120. The controller 302 can determine an appropriate measurement rate of the cauterizer based at least on the mass flow rate of the exhaust gas passing through the concentrator portion 120 and the percentage of sulfur oxide in the exhaust gas. Thus, the disclosed concentrator can be easily adapted to changes in exhaust gas components and / or exhaust gases of different mass flow rates. As a result, the disclosed concentrator can simultaneously concentrate concentrated landfill leachate and remove contaminants (eg, sulfur oxides) from landfill gas flare exhaust or reciprocating engine or turbine exhaust.

Ammonia removal

Ammonia is an air pollutant, and when released into the atmosphere, it becomes a precursor for forming fine particles in the exhaust gas. Because ammonia is water soluble, it is usually found in wastewater (eg, leachate) in landfill facilities, not landfill gas.

In the context of the concentrator and fluid scrubber described herein, known principles for ammonia removal can be used. For example, a wastewater feed containing ammonia can be treated with an agent capable of increasing the pH of the leachate (eg, cautery or alkali (eg, sodium hydroxide or lime)). When the leachate having an increased pH is sent into the air stripper, the ammonia in the wastewater moves into the exhaust of the air stripper. The exhaust from the air stripper can be combined with flare operation to provide heat to the enrichment process, combustion and excess air used in the reciprocating motion of the engine or turbine.

Within the flare, engine or turbine reciprocating motion, ammonia introduced through the combustion air can advantageously reduce another pollutant, nitric oxide (NOx). Nitric oxide (NOx) may be present in the combustion product. This reduction can be achieved through a process known as selective non-catalytic reduction of NOx emissions. As ammonia enters the concentration process with the hot gas from the waste heat source, a reagent suitable for converting the ammonia into a stable salt (such as in the removal of SOx with an alkaline scrub compound) is introduced into the process. be able to. For example, sulfuric acid can be introduced into waste water (eg, leachate) that has come out of the air stripper. This acid can be used to sequester the ammonia as ammonium sulfate (NH 4) 2 SO 4 in the concentrated liquid.

As shown in FIG. 17, another embodiment of a concentrator used to scrub ammonia from landfill leachate may include a cautery or alkali inlet 195. The cautery or alkali inlet 195 is connected to the leachate input line 186. The cauterizer / leachate mixture is routed through the inline air stripper 201 and then sent to the concentrator portion 120. The air stripper 201 can draw gaseous ammonia, which is released into the stripping gas by a previously added cauterizer or alkali. This withdrawn gaseous ammonia can be returned to the landfill gas flare 130 or reciprocating engine or turbine through the ammonia delivery line 194. As described above, flare 130, ammonia in the reciprocating engine or turbine can advantageously reduce NOx emissions. Nevertheless, ammonia can be sequestered as a stable salt by reagent added from reagent source 197 through reagent inlet 199 in concentrator portion 120. In this way, the disclosed concentrator can scrub ammonia from the leachate stream while converting the ammonia into a by-product that can be easily processed.

One aspect of the process for removing sulfur from a landfill gas described herein includes combining a heated gas and liquid stream of wastewater under pressure to form a mixture, and reducing the static pressure of the mixture. Evaporating a portion of the liquid in the mixture to obtain a partially evaporated mixture comprising a mixed concentrated liquid and a liquid concentrate, and contacting the partially evaporated mixture with an alkaline agent. Reducing sulfur oxides in the partially evaporated mixture; removing the contaminated concentrated liquid and a portion of the reduced sulfur oxides from the evaporated mixture to obtain a demisted gas; including.

Another aspect of the process for removing sulfur from the landfill gas described herein includes recycling and combining the wastewater liquid and the liquid concentrate.

Yet another aspect of the process for removing sulfur from a landfill gas as described herein is to remove a portion of the contaminated concentrated liquid and reduced sulfur oxide from the partially evaporated mixture. Passing the partially evaporated mixture into a crossflow scrubber, wherein the crossflow scrubber removes a portion of the contaminated concentrated liquid and reduced sulfur oxide from the partially evaporated mixture. And a step operable to remove.

In yet another aspect of the process for removing sulfur from landfill gases described herein, the temperature of the partially evaporated mixture is about 150 degrees Fahrenheit to about 190 degrees Fahrenheit (about 66 to about 88).

Yet another aspect of the process for removing sulfur from a landfill gas described herein includes generating exhaust gas by combustion of fuel.

Yet another aspect of the process for removing sulfur from a landfill gas described herein includes selecting the fuel from the group consisting of landfill gas, natural gas, propane, and combinations thereof. .

Yet another aspect of the process for removing sulfur from a landfill gas described herein includes combusting the landfill gas.

Yet another aspect of the process for removing sulfur from a landfill gas described herein includes combusting natural gas.

In yet another aspect of the process for removing sulfur from landfill gases described herein, the temperature of the heated gas is from about 900 degrees Fahrenheit to about 1200 degrees Fahrenheit (about 482 to about 649). .

In yet another aspect of the process for removing sulfur from landfill gas described herein, the wastewater is about 1 wt.% Based on the total weight of the leachate. % To about 5 wt. % Solids.

In yet another aspect of the process for removing sulfur from landfill gas described herein, preferably, the liquid concentrate is at least about 10 wt.% Based on the total weight of the concentrate. % Solids, more preferably the liquid concentrate is at least about 20 wt. % Solids, more preferably the liquid concentrate is at least about 30 wt. %, And even more preferably, the liquid concentrate is at least about 50 wt. % Solids.

In yet another aspect of the process for removing sulfur from landfill gases described herein, the partially evaporated mixture is about 5 wt. % To about 20 wt. % Liquid, more preferably the partially evaporated mixture is about 10 wt.% Based on the total weight of the partially evaporated mixture. % To about 15 wt. % Liquid

Yet another aspect of the process for removing sulfur from landfill gases described herein includes combusting natural gas directly from a natural gas source.

Yet another aspect of the process for removing sulfur from a landfill gas described herein includes selecting the wastewater from the group consisting of leachate, countercurrent water, product water, and combinations thereof.

Yet another aspect of the process for removing sulfur from a landfill gas described herein includes selecting the alkaline agent from the group consisting of sodium hydroxide, calcium carbonate, and mixtures thereof.

Yet another aspect of the process for removing sulfur from landfill gases described herein is to combine the heated gas and a liquid stream of wastewater containing an alkaline agent under pressure to form a mixture thereof. Reducing the sulfur oxide and lowering the static pressure of the mixture to evaporate a portion of the liquid in the mixture to obtain a partially evaporated mixture containing a mixed concentrated liquid and a liquid concentrate And removing a portion of the contaminated concentrated liquid and reduced sulfur oxide from the evaporated mixture to obtain a demisted gas.

One aspect of the process for ammonia from landfill leachate described herein includes combining the liquid stream of the wastewater with a pH raising agent to form a wastewater stream with increased pH; A stream of wastewater having an increased pH under conditions sufficient to remove ammonia from the wastewater is contacted with an air stream to provide an exhaust stream rich in ammonia, a small amount of ammonia, and an increase in pH. Reducing the static pressure of the mixture by combining the heated gas with a flow of wastewater containing a small amount of ammonia and increasing the pH under pressure to form a mixture of both, Evaporating a portion of the liquid in the mixture to obtain a partially evaporated mixture comprising the contaminated concentrated liquid and the liquid concentrate; Some of the serial mixed concentrated liquid was removed from the mixture as the evaporator, and a step of obtaining a de-misting gas.

Yet another aspect of the process of removing ammonia from the landfill leachate comprises combining the ammonia-rich exhaust stream and a combustion air stream, and burning fuel in the presence of the combined air stream. And forming an exhaust gas containing the heated gas.

Yet another aspect of the process of removing ammonia from the landfill leachate includes selecting a cautery agent as the pH raising agent.

Yet another aspect of the process of removing ammonia from the landfill leachate includes selecting one of sodium hydroxide and lime as the ablation agent.

Yet another aspect of the process for concentrating wastewater according to the present disclosure is the step of combining heated gas and liquid wastewater within a duct seal to form a mixture, the mixture being disposed downstream of the seal duct. Under the influence of the negative pressure applied from the induction fan, the mixture flows through the part of the duct whose cross-sectional area is limited rather than the cross-sectional area where the mixture is generated, This accelerates the flow rate, generates turbulence, and due to the turbulent flow coming into contact with the discontinuous liquid phase, between the continuous gas phase and the surface of the restricted duct opening. A shear force is generated in between, so that the flowing liquid droplets and other geometric shapes become very fine droplets, and thus between the flowing gas and the liquid wastewater. The interfacial surface area expands, thereby rapidly approaching the adiabatic saturation temperature of the gas-liquid mixture through fast heat and gas-to-liquid and liquid-to-gas mass transfer, respectively, resulting in entrained concentrated liquid and liquid concentrate A partially evaporated mixture is obtained, and a portion of the contaminated concentrated liquid is removed from the evaporated mixture to obtain a demisted gas.

While certain representative embodiments and details have been described for purposes of illustration of the invention, those skilled in the art will recognize the methods and apparatus disclosed herein without departing from the scope of the invention. It is clear that various changes can be made.

Claims (16)

A system for concentrating waste water and reducing sulfur oxide (SOx),
A gas inlet,
A gas outlet;
A concentrating portion having a narrow portion for facilitating gas flow within the concentrating portion and disposed between the gas inlet and the gas outlet;
A liquid inlet disposed in the concentrated portion upstream of the narrow portion and injecting waste water into the concentrated portion;
A demister disposed downstream of the narrow portion to remove entrained droplets from the gas stream;
An alkaline agent storage tank for holding a supply of alkaline agent, connected to the concentrated portion for injecting alkaline agent into the concentrated portion;
Including the system. The system of claim 1, further comprising an alkaline agent pump connected to the alkaline agent storage tank. The system of claim 2, wherein the alkaline agent storage tank is connected to a liquid inlet. The system of claim 2, wherein the alkaline agent storage tank is connected to the concentrated portion upstream of the narrow portion. The system of claim 2, wherein the entrained droplets removed by the demister collect in a sump. The system of claim 5, wherein a sump is connected to the settling tank, and the collected liquid and solid portions of the entrained droplets are separated from each other in the settling tank. 6. The system of claim 5, wherein the settling tank is connected to the sump having a return line that returns a liquid portion of the collected entrained droplets to the sump. A system for concentrating waste water and removing ammonia,
A gas inlet,
A gas outlet;
A concentrating portion having a narrow portion for facilitating gas flow within the concentrating portion and disposed between the gas inlet and the gas outlet;
A liquid inlet disposed in the concentrated portion upstream of the narrow portion and into which non-concentrated wastewater is injected into the concentrated portion;
A demister disposed downstream of the narrow portion to remove entrained droplets from the gas stream;
A pH raising agent inlet line for injecting the pH raising agent into the non-concentrated wastewater upstream of the liquid inlet;
an air stripper upstream of the liquid inlet and downstream of the pH elevating agent inlet line to remove ammonia from wastewater discharged into the air stripper exhaust by the pH increasing agent;
Including the system. The system of claim 8, wherein the pH raising agent inlet line is connected to the liquid inlet. 9. The system of claim 8, wherein the pH raising agent inlet line is connected to a concentrated portion upstream of the narrow portion. The system of claim 8, wherein the entrained droplets removed by the demister collect in a sump. 12. The system of claim 11, wherein a sump is connected to the settling tank and the collected liquid and solid portions of the entrained droplets are separated from each other in the settling tank. The system of claim 11, wherein the settling tank is connected to the sump having a return line that returns a liquid portion of the collected entrained droplets to the sump. The system of claim 8, wherein the pH raising agent is one of caustic. 9. The system of claim 8, wherein the removed ammonia is supplied to the flare via a supply line between the air stripper and the flare. 9. The system of claim 8, further comprising a reagent inlet of the concentrated portion that supplies a reagent to the concentrated portion and the reagent chemically reacts with ammonia in waste water to form a stable salt.

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