KR20090036546A - A heat recycling system for use with a gasifier - Google Patents

Abstract

The present invention provides a system that recycles heat recovered from hot products of a carbonaceous feedstock gasification process back into the gasification process. The hot gaseous products are used to heat working fluids such as air and water to produce hot air, hot water or steam. The heated fluids are used to return heat back to the gasification process. The system also comprises a control system to optimize the efficiency of a gasification process by minimizing energy consumption of the process, while also maximizing energy production.

Description

Heat recycling system for use with gasifiers {A HEAT RECYCLING SYSTEM FOR USE WITH A GASIFIER}

The present invention relates to a system for recovering heat generated by a gasification process of carbon-containing feeds, and specifically gasification, and recycling this heat for use therein and, optionally, for external applications.

Gasification is a process that converts carbon-containing feeds, such as municipal solid waste (MSW) or coal, into combustible gases. This gas can generate electricity, steam or can be used as a basic raw material to produce chemicals and liquid fuels. Possible uses of this gas include the following: combustion in boilers for the production of steam for internal processing and / or for other external purposes, or for generating electricity through steam turbines; Direct combustion in gas turbines or gas engines for the production of electricity; Fuel cells; Production of methanol and other liquid fuels; Use as an additional feed for the production of chemicals such as plastics and fertilizers; Emissions of both hydrogen and carbon monoxide as separate industrial fuel gases; And other industrial applications.

In general, the gasification process consists of supplying a carbon-containing feed to a heated chamber (gasifier) with a controlled and / or limited amount of oxygen and optionally steam. Unlike incineration or combustion, which is operated with excess oxygen to produce CO ₂ , H ₂ O, SO _x , and NO _x , the gasification process produces a crude gas composition comprising CO, H ₂ , H ₂ S and NH ₃ . To produce. After clean-up, the major gasification products of interest are H ₂ and CO.

Useful feeds include any municipal waste, waste from industrial activities and biomedical waste, sewage, sludge, coal, heavy oil, petroleum coke, heavy refinery residue, refinery waste, hydrocarbon contaminated waste ( soil), biomass and agricultural waste, tires and other hazardous waste. Depending on the origin of the feed, the volatiles are H ₂ O, H ₂ , N ₂ , O ₂ , CO ₂ , CO, CH ₄ , H ₂ S, NH ₃ , C ₂ H ₆ , unsaturated hydrocarbons such as acetylene , Olefins, aromatics, tars, hydrocarbon liquids (oils) and charcoal (carbon black and ash). As the feed is heated, water is the first component to evaporate. As the temperature of the dry feed increases, pyrolysis occurs. During pyrolysis, the feed is thermally decomposed to release tar, phenol and light volatile hydrocarbon gas, which is converted to charcoal.

Charcoal contains residual solids consisting of organic and inorganic materials. After pyrolysis, the char has a higher concentration of carbon than the dry feed, which can serve as a source of activated carbon. In gasifiers operating at high temperatures (> 1,200 ° C.), or in systems with high temperature regions, the inorganic mineral material is fused or vitrified to form a material such as molten glass called slag.

Since the slag is in a fused vitrified state, it is generally known to be nonhazardous and can be sold to ore, road beds or other building materials or disposed of in landfills as a nonhazardous material. Due to the extreme fuel consumption in the heating process and the additional waste of treating materials that can be converted into useful syngas and solid materials into residual waste, it is becoming less desirable to dispose of the waste by incineration.

Means for achieving the gasification process vary in many ways, but depend on four main engineering factors: the atmosphere in the gasifier (level of oxygen or air or steam content); Design of gasifiers; Internal and external heating means; And operating temperature for the process. Factors affecting the quality of the product gas include: feed composition, recipe and particle size; Gasifier heating rate; Residence time; Plant configuration, including whether to use a design of a drying or slurry supply system, a feed-reaction flow geometry, a dry ash or slag mineral removal system; Whether to use direct or indirect heat generation and transfer methods; And syngas purification systems. Gasification is generally carried out at temperatures ranging from about 650 ° C. to 1200 ° C., under vacuum, at atmospheric pressure, or at pressures up to about 100 atmospheres.

There are many systems, generally known as integrated circulation systems, that are proposed to capture heat generated by the gasification process and use this heat to generate electricity.

The energy from the gas produced through the gasification system and coupled with the significant amount of recoverable detectable heat produced by the process can generally produce enough electricity to run the process, thereby reducing the cost of local electricity consumption. Can be reduced. The amount of power needed to gasify one ton of carbon-containing feed is directly dependent on the chemical composition of the feed.

If the gas produced in the gasification process contains a wide variety of volatiles, such as a kind of gas that tends to be produced in a low temperature gasifier using a "low quality" carbonaceous feed, this is generally referred to as an emission gas. do. When the characteristics of the feed and the conditions in the gasifier produce a gas in which CO and H ₂ are the predominant chemical species, this gas is referred to as syngas. Some gasification plants utilize techniques to convert crude offgas or crude syngas into more refined gas compositions prior to cooling and washing through a gas quality control system.

Gasification of materials using plasma heating techniques has been commercially available for many years. The plasma is a high temperature luminescent gas, which is partially or wholly ionized and is composed of gas atoms, gas ions and electrons. The plasma can be generated with any gas in this way. This is because plasma may be neutral (eg, argon, helium, neon), reducing (eg, hydrogen, methane, ammonia, carbon monoxide), or oxidizing (eg, air, oxygen, carbon dioxide). Provides excellent control over chemical reactions in On the bulk, the plasma is electrically neutral.

Some gasification systems utilize plasma heat to operate the gasification process at high temperatures and / or convert, reconstitute or modify longer chain volatiles and tars into smaller molecules with or without the addition of other inputs or reactants. Purify offgas / synthesis gas. If gaseous molecules come into contact with plasma heat, they will break down into constituent atoms. Many of these atoms will react with other input molecules to form new molecules, while other atoms can recombine themselves. As the temperature of the molecule in contact with the plasma heat decreases, all atoms are fully recombined. Since the input gas can be stoichiometrically controlled, the output gas can be controlled to produce, for example, significant levels of carbon monoxide and trace levels of carbon dioxide.

Very high temperatures (3000-7000 ° C.) that can be achieved with plasma heating allow for hot gasification processes, where as-received conditions involving liquids, gases and solids in any form or combination Actually any input feed may be accommodated, including waste from wastewater. Plasma technology may be located in the first gasification chamber to allow all reactions to occur simultaneously (hot gasification), or may be placed in the system to cause them to occur sequentially (cold gasification where high temperature purification takes place), or a combination thereof.

The gas produced during the gasification of the carbon containing feed is generally very hot, but it may contain small amounts of unwanted compounds and requires further treatment to convert them into usable products. Once the carbon containing material has been converted to the gaseous state, unwanted materials such as metals, sulfur compounds and ash can be removed from the gas. For example, dry filtration systems and wet scrubbers are often used to remove particulate matter and acid gases from gases generated during gasification. A number of gasification systems have been developed, including systems for treating gases generated during gasification processes.

Such factors are described, for example, in US Pat. Nos. 6,686,556, 6,630,113, 6,380,507; 6,215,678, 5,666,891, 5,798,497, 5,756,957, and the design of several different systems described in US patent application 2004/0251241, 2002/0144981. U.S. Patent 4,141,694; 4,181,504; 4,208,191; 4,410,336; 4,472,172; 4,606,799; 5,331,906; There are also a number of patents relating to various techniques for gasifying coal for the production of syngas for use in various applications, including 5,486,269, and 6,200,430.

Conventional systems and processes do not adequately address the problems that must be addressed on a continuously changing basis. Some of these types of gasification systems describe means for adjusting the method of producing useful gases from gasification reactions. Thus, it would be a major advance in the art to provide a system that can efficiently gasify carbon-containing feeds in a manner that maximizes the overall efficacy of the process and / or the steps comprising the entire process.

The contents of this background are for the purpose of providing known information which is considered by the applicant to be as relevant as possible with the present invention. Any information mentioned above is not necessarily to be construed as or constitutes a prior art against the present invention and should not be so interpreted.

Summary of the Invention

The present invention provides a system for optimizing the efficiency in gasifying a carbon-containing feed by recovering the heat detectable from the gasification process and recycling it for use therein and optionally for external application.

The present invention provides a system for recycling heat recovered from hot gas and transferring the recycled heat back to the gasifier. In particular, the system is a means for delivering a hot gas to a gas-to-fluid heat exchanger, in which heat from the hot gas is transferred to the fluid to produce a heated fluid and Means for producing a cooled gas and means for delivering the heated fluid to the gasifier. The heated fluid moves into the gasifier to provide the heat necessary to cause the gasification reaction. The heated fluid can also optionally be used to preheat or pretreat the feed to be gasified directly or indirectly.

According to one embodiment of the invention, the system also includes a control system comprising a sensing element for monitoring the operating parameters of the system and a reactive element for adjusting operating conditions within the system to optimize the gasification process. The reaction device optimizes the efficiency of the gasification process by adjusting operating conditions in the system according to the data obtained from the sensing device, thereby minimizing energy consumption of the gasification process while maximizing energy production.

According to one aspect of the invention, a process for improving the efficiency of the gasification process of a carbon-containing feedstock by recycling the detectable heat from the hot gases produced by the gasification process back to the gasification process using a gas-to-fluid heat exchanger. Provided, the method comprising passing a hot product gas through a gas-to-fluid heat exchanger; Passing the cooling fluid through a gas-to-fluid heat exchanger; Heat from the hot product gas is transferred to the cooling fluid through a gas-to-fluid heat exchanger to exit the cooled product gas exiting the heat exchanger through the cooled product gas outlet, and the heat exchanger through the heated fluid outlet. Generating an exiting heated fluid; And providing heat for the gasification process of the carbon containing feed using the heated fluid.

Brief description of the drawings

These and other features of the present invention will become more apparent from the following detailed description with reference to the accompanying drawings.

1 is a process flow diagram for a system for recycling heat recovered from a hot gas product of a gasification process back to a gasifier, according to one embodiment of the invention.

2 is a process flow diagram for recovering heat from a gas product of a gasification process using a heat exchanger and a heat recovery steam generator in accordance with one embodiment of the present invention.

3 is a process flow diagram for a cooling system of hot gas product comprising a heat exchanger for recovering heat from the gas product of the gasification process and a quench step for further product gas cooling, according to one embodiment of the invention.

4A is a schematic diagram showing functional requirements for a gas-to-air heat exchanger, according to one embodiment of the invention.

4B is a schematic diagram illustrating a gas-to-air heat exchanger, according to one embodiment of the invention.

5 is a schematic diagram illustrating a gas-to-air heat exchanger, according to one embodiment of the invention.

6 is a schematic diagram of a transducer and its various inputs, according to one embodiment of the invention.

7 is a schematic diagram illustrating a possible end use of the exchange-steam generated by heat recovery from the product gas in a heat recovery steam generator, according to various embodiments of the present invention.

8 is a schematic diagram illustrating a piping system for delivering exchange-air to a converter according to one embodiment of the present invention.

9 is a schematic diagram illustrating a high level of conception for various temperature control within a system, in accordance with an embodiment of the present invention.

10 is a schematic diagram illustrating a high level view of a gas flow / pressure control subsystem, in accordance with an embodiment of the present invention.

11A-11I are process flow diagrams schematically illustrating various embodiments of the present invention.

Figure 12 shows a cross-sectional view of one embodiment of a gasifier according to one embodiment of the present invention, in which the positions of the feed inlet, gas outlet, solid residue outlet, and exchange-air inlet are shown in detail.

FIG. 13 shows a central longitudinal cross-sectional view of one embodiment of a gasifier, detailing the location of the feed inlet, the gas outlet, and the air box.

FIG. 14 shows the air box assembly of the gasifier shown in FIG. 13 in detail.

Detailed description of the invention

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

As used herein, the term “about” means a variation of ± 10% from the nominal value. Such variation is to be understood as always being included in any given value provided herein, whether or not specifically mentioned.

For the purposes of the present invention, the term syngas means the product of a gasification process, which may include carbon monoxide, hydrogen and carbon dioxide in addition to other gaseous components such as methane, nitrogen and water vapor.

As used herein, the term “exchange-air” means air after being heated using senseable heat from the product gas using a gas-to-air heat exchanger according to the invention. It is within the scope of the present invention to heat gases other than air, including but not limited to oxygen or enriched air, using the systems described herein.

As used herein, the term “converter” refers to an apparatus for converting a carbon containing feed into a crude syngas product, also referred to as product gas. The transducer includes a gasifier and a plasma gas reformer.

As used herein, the term "(carbon containing) source" may be any carbon containing material suitable for gasifying with the gasification process of the present invention, including but not limited to any waste, coal (coal fired generator) Low grades, including large quantities of sulfur containing coal, which are not suitable for use in petroleum), petroleum coke, heavy oil, biomass, sewage sludge, sludge from pulp and paper machines, and agricultural waste. Suitable wastes for gasification include both hazardous and non-hazardous wastes, such as municipal waste, waste produced by industrial activities (paint sludge, off-spec paint products, absorbents consumed), automotive fluff ), Waste tires and biomedical wastes, any carbon containing material not suitable for recycling, such as non-recyclable plastics, sewage sludge, coal, heavy oil, petroleum coke, heavy refining residues, refining wastes, hydrocarbon contaminated solid wastes, and Biomass, agricultural waste, tires, hazardous waste, industrial waste and biomass. Examples of biomass useful for gasification include, but are not limited to, wool dregs or raw wool, residues from fruit, vegetable and grain processing, residues from paper machines, straw, grass and manure do.

As used herein, the term “product gas” generally refers to a gas produced by a gasification plant before being cooled and washed by a process designed to remove contaminants. Depending on the design of the gasification plant, this term can be used, for example, to refer to crude off-gas, crude syngas, reformed off-gas or reformed syngas.

As used herein, the terms "gas-to-air heat exchanger" and "gas heat exchanger" are used interchangeably, which means heat exchangers used to transfer detectable heat from hot gas products to air.

A “sensing element” is defined to describe any element of a system configured to sense a characteristic of a process, process input or process output, wherein the feature monitors, adjusts and monitors one or more local, regional and / or overall processes of the system. And / or may be indicated by characteristic values available for control. The sensing element includes, but is not limited to, a sensor; Detectors; monitor; An analyzer; Or process, fluid and / or material temperature, pressure, flow, composition and / or other such properties, and the location and / or placement of materials at any given point in the system, and any operating characteristics of any process apparatus used within the system. May include any combination thereof.

“Responsive element” is defined to describe any element of a system configured to respond to a sensed characteristic to operate a process device that is operably associated therewith in accordance with one or more predetermined or computerized control parameters. Control parameters are defined to provide the desired process results. The reactive element is not limited to these, but may be configured to impart a physical action to the device based on a driver, statically and / or dynamically varying power source, inducer, and one or more control parameters. It may include a device. Reaction elements are not limited to these, but are not limited to material input mechanisms, plasma heat sources, additive input means, gas blowers, additive input blowers, gas flow regulators, additive input flow regulators, solid residue handlers, additive input regulators and plasma heat source regulators. And may be operatively connected to various processing apparatus, which may include and to such other processing apparatus operable to affect any local, regional and / or overall process.

The present invention provides a system for optimizing efficiency in a process for gasifying a carbon-containing feed into a gaseous product by minimizing energy consumption of the process while maximizing energy production. In particular, the present invention relates to heat for use with a gasifier wherein the detectable heat from the gasification process is efficiently recovered and transferred to one or more processes within the system and optionally to processes outside the system. Provide a recycling system.

The system is a heat exchange system for recovering heat from a hot product gas, which includes a heat exchange system that transfers detectable heat from the product gas to a suitable fluid. Fluids suitable for this heat exchange process include, but are not limited to, air, water, oil or other gases such as nitrogen or carbon dioxide. Specifically, the system is a conduit system for delivering a hot product gas of a gasification process to a gas-to-fluid heat exchanger, in which heat from the hot product gas is transferred to the fluid to produce heated fluid and cooled production. A conduit system from which gas is produced. The system further includes another conduit system for delivering the heated fluid to the gasification process.

In one embodiment, the gas-to-fluid heat exchanger is a gas-to-air heat exchanger in which heat is transferred from the product gas to air to produce heated exchange air. In one embodiment, the gas-to-fluid heat exchanger is a heat recovery steam generator in which heat is transferred to water to produce heated water or steam.

According to one embodiment of the invention, schematically illustrated in FIG. 1, there is shown a heat recycling system 5000 for transferring heat generated during the gasification process back to the converter 1000 to induce a gasification reaction. In one embodiment, this is achieved by heating the air 5010 with heat from the hot product gas 5020 produced in the converter 1000 in a gas-to-air heat exchanger 5100 to produce a heated air product (hereinafter, This is done by generating exchange-air 5015) and cooled product gas 5025, and moving the heated exchange-air 5015 back to the converter 1000.

Thus, thermal efficiency is optimized by this system because the recovered detectable heat is recycled back to the gasification process, thereby reducing the amount of energy input required from an external source for drying, volatilizing and gasifying the feed. The recovered detectable heat may also serve to minimize the amount of plasma heat required to achieve the defined product gas quality. Thus, the present invention enables efficient gasification of the carbon-containing feed, wherein the heat required for gasification is provided by hot exchange-air heated using detectable heat recovered from the hot product gas.

The detectable heat transferred from the product gas to the heated exchange-air can also be used for applications for heating elsewhere in the gasification process, as well as for applications for external heating.

For example, heated exchange-air can be used directly or indirectly to preheat or pretreat the source to be gasified. In the case of a direct heating / preheating step, the exchange-air passes directly through the feed to heat and / or remove moisture. In the case of an indirect heating / pretreatment step, heat is transferred from the heated exchange-air to the oil (or to water to produce steam), where the heated oil (or steam product) is transferred to the feed dryer / preheater. Used to heat the wall. In all cases, by recognizing the recycling of heat, the energy input required for these heating applications is minimized.

Thus, it is within the scope of the present invention to transfer heat from heated exchange-air to any working fluid of interest. The working fluids noted above include, but are not limited to, oils, water, or other gases such as nitrogen or carbon dioxide. If heat is transferred to a working fluid other than air, a suitable heat exchange system is used.

After heat is recovered in the gas-to-air heat exchanger, the product gas, although cooled, still contains too much heat and can be subjected to filtration and treatment steps known in the art. Thus, the present invention optionally provides for further cooling of the product gas prior to the subsequent filtration and treatment steps described above.

In the embodiment shown in FIG. 2, thermal recirculation system 5001 uses air from hot product gas 5020 in a gas-to-air heat exchanger 5102 to heat air 5010 to heat the air. Product (hereinafter referred to as exchange-air 5015) and partially cooled product gas 5023 are produced, and the heated exchange-air is passed back into converter 1000.

Thermal recirculation system 5001 also includes a subsystem for recovering additional heat from the product gas 5023 after the partially cooled product gas 5023 passes through the gas-to-air heat exchanger 5102. do. Thus, the system 5001 further includes a heat recovery steam generator 5302 whereby additional heat recovered from the product gas converts water 5030 into steam (called exchange-steam 5035). To produce a sufficiently cooled product gas product 5025.

The exchange-steam generated in the heat recovery steam generator can be used to run downstream energy generators, such as steam turbines, and / or can be used in direct operated turbines and / or added to the gasification process. The exchange-steam can also be used, for example, in other systems for extracting oil from tar sand or in topical heating applications, or can be supplied to local industrial clients for their purposes. In one embodiment, the steam produced using heat from the product gas is saturated steam. In another embodiment, the steam generated using heat from the product gas is superheated steam, which can be produced directly through heat exchange between water and product gas, or saturated steam and product gas.

The system of the present invention is for use with a converter in which the feed is converted (via the effluent gas intermediate) to a high temperature crude gaseous product. Typical converters for use in the present invention include a feed inlet for inputting a feed to gasify, one or more exchange-air inlets for providing heated exchange-air to run the gasification process, and a hot feed gas outlet, and Optionally one or more process additive inlets. The converter also includes one or more plasma heat sources for converting the offgas intermediate of the gasification process into the crude product gas.

If the system does not include a system for recovering additional heat from the product gas after the partially cooled product gas has passed through the gas-to-air heat exchanger, Other systems may be provided. In one embodiment shown in FIG. 3, the hot product gas 5020 is cooled in a gas-to-air heat exchanger 5103 to partially cool the product gas 5023 and the heated exchange-air 5015. The generating system 5003 also includes a dry quench step 6103 for further cooling the product gas prior to processing. The dry quench step described above is adapted to remove excess heat from the product gas by adding a controlled amount of sprayed water 6030 to provide cooled product gas 5025 that may be needed in subsequent filtration and processing steps. Is provided. The selection of a system suitable for further cooling the product gas prior to treatment is within the knowledge of those skilled in the art.

According to one embodiment of the invention, the system also includes a control subsystem comprising a sensing element for monitoring the operating parameters of the system and a reactive element for adjusting operating conditions within the system to optimize the gasification process. In addition, the reaction element adjusts the operating conditions in the system according to the data obtained from the sensing element, thereby optimizing the efficiency of the gasification process by maximizing energy generation while minimizing the energy consumption of the process.

The control subsystem can also be used to optimize the composition (ie, calorific value) of the resulting product gas and optionally keep the system within safe operating parameters.

heat transmitter

The present invention provides a system for transferring heat generated during the gasification process back to the gasifier to induce a gasification reaction. It uses a heat exchange system (eg a gas-to-fluid heat exchanger) to transfer heat from the product gas to a suitable working fluid, thereby recovering detectable heat from the hot product gas, thereby heating the heated fluid. And by producing cooled product gas. In one embodiment, the heated fluid produced in the gas-to-fluid heat exchanger moves back into the gasifier.

In one embodiment, the gas-to-fluid heat exchanger includes one or more gas-to-air heat exchangers.

Functional requirements for the gas-to-air heat exchanger are shown in FIG. 4A, where hot product gases 5020 and air 5010 pass through the gas-to-air heat exchanger 5104A, respectively. Sensable heat is transferred from hot product gas 5020 to air 5010 (blowing by process air blower 5012) to provide heated exchange-air 5015 and cooled product gas 5025. .

Various classes of heat exchangers can be used in the system of the present invention, such heat exchangers include shell and tube heat exchangers, straight single pass and U-tube heat exchangers, repeat pass designed heat exchangers, and Plate type heat exchangers are included. Selection of a suitable heat exchanger is within the knowledge of those skilled in the art.

Some particulate material will be present in the product gas such that the gas-to-air heat exchanger is specifically designed for high levels of particulate loading. The particle size is typically from 0.5 to 100 microns. In one embodiment shown in FIG. 4B, the heat exchanger is a single pass vertical flow type heat exchanger 5104B, where product gas 5020 flows to the tube face and air 5010 flows on the shell face. In an embodiment of a single pass vertical flow type heat exchanger, the product gas 5020 flows vertically in a "once through" design, thereby minimizing areas where accumulation of particulate matter or corrosion may occur thereby. .

The rate of product gas should be kept high enough for self cleaning while still minimizing corrosion. In one embodiment, the gas velocity is between 3000 and 5000 m / min. Under normal flow conditions, the gas velocity is from about 3800 m / min to about 4700 m / min.

Due to the significant difference in air input temperature and hot product gases, each tube in the gas-to-air heat exchanger is preferably equipped with individual expansion bellows to prevent tube rupture. Tube rupture can occur when a single tube is blocked and the rest of the tube bundle no longer expands / contracts. In those embodiments where the process air pressure exceeds the product gas pressure, the tube rupture presents a high risk due to problems resulting from the air entering the gas mixture.

In one embodiment of the invention, the system is operated intermittently, ie, to allow for a number of start-ups and interruptions as needed. Therefore, it is important that the device be designed to withstand repeated thermal expansion and contraction.

In order to minimize the potential risk due to tube leakage, the system of the present invention, for example, the temperature transmitter located at the product gas inlet 5501 in FIG. 5, and the product gas outlet 5526 of the gas-to-air heat exchanger. And one or more individual temperature zone transmitters, such as a temperature transmitter 5552 located at), and a temperature transmitter 5583 located at exchange-air outlet 5517. When the temperature transmitter is associated with the product gas outlet 5526 of the gas-to-air heat exchanger 5105, the temperature transmitter is responsible for the temperature rise resulting from combustion when the exchange-air leaks into the product gas conduit. Positioned to detect. If a rise in temperature is detected, automatic operation of the process air blower 5012 will stop to remove the oxygen source.

In the case where the temperature transmitter is associated with the exchange-air outlet 5517 of the gas-to-air heat exchanger 5105, this temperature transmitter ensures that the temperature of the exchange-air is maintained within the set temperature range required for the gasification process. It is used to To avoid supplying excessively heated exchange-air (or excessively hot exchange-air) to the gasification process, which may cause overheating of the feed, control valve 5590 is opened to await excess exchange-air. Exhaust to

In addition, the heat exchanger is provided with ports for equipment installation, inspection and maintenance, and ports for repair and / or cleaning of conduits as necessary.

In one embodiment, the gas-to-fluid heat exchanger is a heat recovery steam generator, which uses the recovered heat to produce an exchange-steam. In one embodiment, water is provided into the heat exchanger in the form of cold steam. In another embodiment, the resulting exchange-steam is saturated or superheated steam.

The exchange-steam thus produced can be used as a process steam additive for gasification processes, or it can be used to run process equipment, such as gas blowers, to run turbines to generate or rotate power.

Steam that is not used during the conversion process to run a process unit that generates or rotates power can be used for other commercial purposes, such as in local heating applications or to improve the extraction of oil from backwash. Exchange-steam can also be used to dry the feed before gasification in the converter by indirectly heating the feed in the feed processor.

The heat recovery steam generators used in one embodiment of the system of the present invention are shell and tube heat exchangers, where the product gas flows vertically through the tubue and water boils on the shell face.

Heat exchange systems for heat recovery steam generators are designed with the understanding that some particulate matter will be present in the product gas. In addition, the rate of product gas here is also maintained at a high enough level for self cleaning of the tube while minimizing corrosion.

Converter for use with the system of the present invention

The system of the present invention includes a converter for converting the feed into a gaseous product. The conversion described above takes place via gasification of the feed and reconstitution of the intermediate gaseous product. The gasification of the feed includes the following steps: i) drying the feed to remove residual moisture, ii) volatilizing the volatile components in the dried feed to produce a charcoal intermediate, and iii) The process of converting charcoal into emissions and ashes. Thus, the gaseous product of the gasification process comprises volatile components and offgases, which are optionally subjected to a reconstitution step to provide the gaseous product. In one embodiment, the reconstruction step is a plasma assisted reconstruction step.

Thus, the converter comprises a refractory-lined chamber with one or more feed inlets, one or more exchange-air inlets, a gas outlet, and a solid residue outlet. The transducer also optionally includes one or more process additive inlets, and one or more plasma heat sources.

In one embodiment, the converter is a horizontally oriented gasifier, where the feed enters the gasifier through a feed inlet located at one end of the gasifier. The feed is gasified as it moves towards the solid residue outlet located at the other end of the gasifier.

The gasification process can also be performed in one of a number of standard gasifiers as known in the art. Examples of gasifiers known in the art include, but are not limited to, entrained flow reactor vessels, fluidized bed reactors, and rotary furnace reactors, each of which may be solid, particulate, slurry, liquid, gas, or And a feed in the form of a combination thereof. Gasifiers can have a wide range of length-to-diameter ratios and can be oriented vertically or horizontally.

In each of these embodiments, the gasification process is facilitated by introducing heated fluid through a suitably configured heating fluid inlet, in accordance with the present invention. In one embodiment, the gasification process is facilitated by introducing heated exchange-air through the exchange-air inlet.

In accordance with the present invention, the heated fluid can be provided into various regions of the gasifier, if necessary, through an independent heated fluid supply and distribution system.

In one embodiment, the heated fluid supply and dispersion system includes an exchange-air inlet capable of introducing the heated exchange-air into the gasification zone.

These inlets are located in the transducer and distribute the heated exchange-air through the transducer to initiate and direct gasification of the feed. In one embodiment, the exchange-air inlet comprises a perforation located at the bottom of the gasifier. In one embodiment, the exchange-air includes a perforation located on the wall of the gasifier.

In one embodiment, the exchange-air inlet includes a separate air box for each zone from which hot exchange-air can move to the zone through a perforation in the bottom of the transducer. In one embodiment, the exchange-air inlet is a sparger controlled independently for each zone.

Optionally, in order to prevent clogging of the exchange-air inlet during the process, the inlet hole size is chosen such that it forms a limit and thus a pressure drop across each hole. This pressure drop is sufficient to prevent waste particles from entering the inlet hole. The inlet hole may optionally be tapered outwardly toward the top surface such that particles do not collide in the hole.

The converter may be designed such that the process of converting the feed to the product gas (ie, the gasification and reconstitution steps) are all generally performed in a single area or chamber within the system.

The converter may also be designed such that the process of converting the feed to the product gas takes place in more than one zone, ie the gasification and reconstitution steps are separated to some extent from each other in a separate zone within the system. In a transducer of this kind, the process takes place in more than one area in the chamber, in a separate chamber, or in some combination of these, where the areas are in fluid communication with each other.

In a multi-zone converter, the first or main, zone or chamber (also referred to as gasifier) dries the feed (if residual moisture is present), extracts the volatile constituents of the feed and extracts the resulting charcoal. It is used to heat the feed to convert gaseous products and ash to produce offgas products, while the second zone or chamber (also referred to as reconstructor) allows plasma heat to be completely converted into offgas and volatiles into the offgas. And other process additives (eg, air and / or steam). If two or more separate zones or chambers are used for gasification of the feed and conversion of the offgas to the product gas, the gas exiting the final area of the converter is the product gas.

In one embodiment, the various steps of the gasification process may be performed in various regions of the gasifier. One skilled in the art will understand that, conceptually, the conditions at any location of the gasifier can be optimized according to the nature of the feed material at that particular location by separating the gasifier into an infinite number of regions. However, a practical embodiment of this concept is to separate the gasifier into a finite number of regions optimized according to the characteristics of the larger or more common or average feed materials. Thus, it will be apparent to those skilled in the art that the gasifier may be separated into two, three, four or more zones depending on the nature of the feed.

According to one embodiment of the invention, each step of the gasification process is facilitated by introducing an appropriate amount of heated exchange-air through a suitably configured exchange-air inlet.

The feed is introduced through one or more feed inlets arranged to optimally expose the feed to heated exchange-air or other heated fluid in order to ensure that the feed is completely and efficiently converted to a gaseous product.

In one embodiment, the system of the present invention feeds a high carbon feedstock (HCF), such as plastic debris, with the feed prior to introduction into the converter or through a dedicated high carbon feedstock (HCF) inlet. This allows for a quick response to process demands for higher or lower carbon inputs to meet the required gas quality.

An optional process additive inlet is provided for adding gas, such as oxygen, air, oxygen rich air, steam, or other gases useful for the gasification process, to the converter. The process additive inlet may comprise an air input port, a steam input port, an exchange-air input port and an exchange-steam input port. These ports are located in the transducer for optimal dispensing of process additives throughout the transducer. The steam additive may be provided by a heat recovery steam generator.

Oxygen in the exchange-air is also used to balance the chemical properties to produce the required product gas and to remove the maximum amount of carbon. Oxygen also initiates or increases the rate of exothermic reactions that produce carbon monoxide, carbon dioxide, hydrogen and other large hydrocarbon particles. The heat generated from the exothermic reaction together with the heat provided by the heated exchange-air and / or other heated fluid together increases the process temperature in the converter.

6 is a schematic diagram summarizing various inputs and outputs associated with one embodiment of a transducer for use with the system of the present invention. This embodiment includes a converter 1006 that includes a horizontally oriented gasifier 2006 having a feed inlet 2604, where the feed is a municipal solid waste (MSW) and high carbon content feed. Combinations of water HCF (such as plastic). The converter 1006 has a number of exchange-air inlets 2621A, 2619B and 2619C positioned to provide the exchange-air 5015 required for the gasification reaction. The transducer also has an exchange-air inlet 3616 and a steam inlet 3630 located proximate to the plasma torch 3008 to provide the air and steam additives required for the plasma reconstruction reaction. The transducer 1006 has a solid residue outlet 2608 in communication with the solid residue processing chamber 4620.

The material travels laterally through the gasifier to facilitate certain stages of the gasification process (drying, volatilization, conversion of char to ash). Lateral movement of material through such gasifiers is achieved by using one or more side transfer units, including but not limited to movable shelves, movable platforms, pusher rams, flows. , Screw members or belts may be included.

One or more side delivery units may work in an integrated manner, or individual side delivery units may work independently. In order to optimally control the mass flow rate and pile height, the individual side delivery units can move individually at varying speeds, varying travel distances and varying travel frequencies. The side delivery unit should be able to operate effectively in the harsh conditions of the gasifier, in particular at high temperatures.

The transducer may be one or a combination of conventional flame retardant materials known in the art suitable for use in a vessel for unpressurized reaction at high temperature (eg, a temperature of about 1100 ° C. to 1400 ° C.). Lined with flame retardant material. Examples of such flame retardant materials include, but are not limited to, ceramics fired at high temperatures (such as aluminum oxide, aluminum nitride, aluminum silicate, boron nitride, zirconium phosphate, chromium oxide), glass ceramics, and primarily silica, alumina, and titania. It contains a high temperature alumina brick containing.

The solid residue outlet is positioned to remove solid by-products of the gasification reaction from the converter. The solid by-products of the gasification process are also referred to as solid residues, which can take the form of charcoal, ash, slag or some combination thereof, which solids by-products are continuously or through an appropriately configured outlet from the converter. It is removed intermittently. The char may be removed before complete conversion to gaseous product or may remain in the gasifier for further conversion to ash. The ash product is then removed via a solid residue outlet, for example into a recollection chamber, or optionally a solid residue treatment chamber for further processing. The design and location of suitable outlets for solid residue removal in the converter are selected using the knowledge of those skilled in the art, depending on the requirements of the system and the type of by-products to be removed.

The solid residue outlet is generally located at or near the chamber bottom, allowing the residue to be actively removed using gravity flow. Some systems optionally use a solid residue removal system to actively transport residue from the bottom of the converter. The removal of the active solid residues described above can be accomplished by one of a variety of devices known in the art. Examples of such devices include, but are not limited to, screws, pusher rams, horizontal rotating paddles, horizontal rotating arms, and horizontal rotating wheels.

In those embodiments in which the solid residue (eg ash by-product) of the gasification process is further converted to slag, the conversion of ash to slag occurs in the solid residue treatment chamber. A plasma heat source can be used in the solid residue treatment chamber to melt the ash into slag. For example, molten slag at a temperature of about 1100 ° C. to about 1600 ° C. may be periodically or continuously consumed from the solid residue processing chamber and then cooled to form a solid slag material. This slag material is landfilled. This solid product can be further broken down into aggregates for normal use. Alternatively, the molten slag can be poured into a container to form ingots, bricks, tiles or similar building materials.

In the case where the solid residue of the gasification process contains some unconverted carbon, the plasma heat of the slag treatment step causes the aforementioned unconverted carbon to be completely converted into hot gaseous products of fuel value. This gaseous product is referred to as residual gas. In one embodiment, heat is recovered from the hot residue gas using a gas-to-air heat exchanger dedicated to the residue, producing heated air product and cooled residue gas. The cooled residue gas is optionally further processed in a dedicated gas handler subsystem to produce a gas product, which can be combined with the gaseous product of the main gasification process.

System for further cooling the product gas before the processing step

In addition to the gas-to-fluid heat exchanger, the present invention optionally includes a system for further cooling the product gas prior to the treatment step. In one embodiment, the system for further cooling the product gas prior to washing and processing also provides additional heat recovery. If it is desired to recover additional detectable heat from the product gas, the heat is transferred from the product gas to another working fluid, for example water, oil or air. The products of the foregoing embodiments may each comprise heated water (or steam), heated oil, or additional hot air.

In one embodiment, the system of the present invention recovers additional detectable heat from the product gas using a heat exchanger that transfers heat from the partially cooled product gas to water, thereby heating heated water or steam, and further cooling. To produce gas. In one embodiment, the heat exchanger used in this step is a heat recovery steam generator, which uses the recovered heat to produce an exchange-steam. In one embodiment, water is provided into the heat exchanger in the form of cold steam. In another embodiment, the above exchange-steam produced is saturated or superheated steam.

7 shows a relationship between a gas-to-air heat exchanger 5107 and a heat recovery steam generator 5307, according to one embodiment of the invention. The exchange-steam 5035 generated in the heat recovery steam generator 5307 can be used for various downstream applications. 7 illustrates various possible end uses (labels A through G) for exchange-steam produced using a heat recovery steam generator, in accordance with various embodiments of the present invention.

For example, as shown in option D, the resulting exchange-steam 5035 may move into converter 1007 as a process steam additive in one embodiment of the present invention. The exchange-steam 5035 may be used as a process steam additive during the gasification process to ensure sufficient free oxygen and hydrogen to convert the feed to the product gas to the maximum. The use of steam as an oxygen containing process additive is preferred because of its low cost and ease of handling. Steam also contains hydrogen, which may be the desired product of the gasification process.

The generated exchange-steam may also pass through turbine 5715 to operate a rotating process apparatus, for example exchange-air blower 5712 (option B), or product gas blower 5722 (option C). have.

Steam that is not used to run the conversion process or rotary process equipment may be used for other commercial purposes, for example in the generation of electricity through the use of steam turbines (5705) or in local heating applications (5710) (option E). It may be used, or may be supplied to a local industrial client for this purpose, or it may be used to improve oil extraction from tar sand 5780 (option F). The exchange-steam can also be used indirectly with the heat feed in feed controller 5767, thereby allowing the feed to dry before gasification in the converter (option G).

In embodiments in which the system for further cooling the product gas prior to conditioning does not include recovery of additional heat, the cooling step includes a dry quench step, where the product gas temperature is controlled by direct controlled (thermal saturation) injection of sprayed water. Is reduced.

In one embodiment, when cooling of various systems or processes is required, excess heat can be removed (and recovered) by a water cooling step. The heated product gas may in turn be used to heat the thermal working fluid for use elsewhere in the gasification process. The heated water streams are derived from various sources, including but not limited to gas cooling processes in gas conditioning systems or plasma heat source cooling systems. Heated water can also be used to preheat oil for various applications.

Conduit system

Conduit systems are used to move gas from one component of the system to another. Thus, the system includes a product gas conduit system for moving the hot product gas product to a heat exchanger for recoverable heat. The system also includes an exchange-air conduit system for moving the heated exchange-air to the converter, where it is introduced into the converter through the exchange-air inlet. Conduit systems typically use one or more pipes or lines through which gas is carried.

If the system includes a heat recovery system generator, the system will also include an exchange-steam conduit system for moving the heated exchange-stem for use in one or more of the applications listed above. The exchange-steam conduit system may comprise a system of multiple pipes or branched conduits flowing in parallel connection and provided branches are designated for a particular application.

Material and size specifications for the conduit system gas line are selected as needed to provide safe and effective delivery of the gas. If the gas carried is a hot product gas, the thickness of the design and the type of refractory used are selected to ensure that the shell wall temperature is about 200 ° C. in order to be kept above the acid gas dew point to prevent corrosion. In one embodiment, the hot product gas line is carbon steel and the refractory is lining. In one embodiment, the heated exchange-air line comprises stainless steel tubing.

In order to maximize the amount of senseable heat that can be recovered from the hot product gases and to minimize cooling of the heated exchange-air or exchange steam, means are optionally provided in the conduit system to minimize heat loss to the surrounding environment. Heat loss can be minimized through the use of thermal barriers around the conduits, including, for example, by incorporating insulation as known in the art and designing a plant that minimizes the length of the conduits. This is particularly important for high temperature conduits.

In one embodiment, the heated exchange-air is discharged from the gas-to-air heat exchanger in a single pipe and then divided into several smaller diameter pipes to provide various areas of the converter that require heated exchange-air. do. Each branch of the piping system includes an air flow control valve for controlling the various areas of the transducer that require the flow of heated air.

The product gas piping system utilizes one or more flow control devices and / or blowers, optionally located throughout the system, which provide a means for treating the flow rate of the gas product.

The exchange-air conduit system will optionally utilize one or more flow control devices, flow meters, and / or blowers, located throughout the system as needed to control the flow rate of the exchange-air. In one embodiment, as shown in FIG. 8, exchange-air flow control valves 5590A, 5890B, and 5890C are provided to control the flow of exchange-air 5015 to each level of the gasification zone. The control valve controls the flow of exchange-air to the air inlets 2812, 2814 and 2816 for the gasifier 2008. In one embodiment, control valves 5590A, 5890B and 5890C are independently controllable to adjust the amount of exchange-air 5015 introduced into each region of the gasifier.

In one embodiment, there is one exchange-air flow control valve 5892 for controlling the flow of exchange-air to the reconstructor 3008. In this embodiment, the exchange-air is provided as a process additive.

The exchange-air conduit also optionally includes means for diverting the exchange-air to an outlet outlet or any further heat exchange system.

The flow regulating device, and / or the blower, and / or the switching means are optionally controlled by the control subsystem as discussed in detail below.

The conduit system will also optionally include a service port that provides access to the system for performing repair and / or cleaning as well as maintenance of conventional conduits.

Plasma heat source

The system of the present invention utilizes one or more plasma heat sources for converting offgas produced by the gasification process into product gas. The plasma heat source is also provided to a solid residue controller for dissolving and controlling the solid residue.

Various commercially available plasma heat sources can be used in the system that develop an appropriate high flame temperature for a sustained period of time at the point of application. In general, such plasma heat sources are available from about 100 kW to 6 MW in external power. The plasma heat source may utilize one or more combinations of suitable working gases. Examples of suitable working gases include, but are not limited to, air, argon, helium, neon, hydrogen, methane, ammonia, carbon monoxide, oxygen, nitrogen, and carbon dioxide. In one embodiment of the invention, the plasma heat source is continuously performed using air as the plasma medium to generate a temperature in the gasifier above about 900 ° C. to about 1300 ° C. required to convert the offgas to the product gas.

In this aspect, a number of alternative plasma techniques are suitable for use in the present invention. For example, it is understood that transitional arc and non-running arc torches (both AC and DC) using appropriately selected electrode materials can be used. It is also understood that inductively coupled plasma torches (ICP) may also be used. Selection of the appropriate plasma heat source is within the knowledge of those skilled in the art.

In one embodiment of the present invention, one or more plasma heat sources will be positioned to optimize the conversion of offgas to product gas. The location of one or more plasma heat sources is selected depending on the design of the gasification system, for example depending on whether the system uses one or two stage gasification processes. For example, in embodiments utilizing a two-step gasification process, the plasma heat source may be disposed relative to the inlet through which discharge gas passes to enter the reconstitution chamber or reconstruction zone, or may be directed in the direction of the inlet. In embodiments utilizing a one step gasification process, one or more plasma heat sources may reach the core of the gasifier. In all cases, the location of the plasma heat source is chosen according to the requirements of the system and for optimal conversion of offgas to product gas.

In one embodiment, the plasma heat used in the plasma reconstructor is provided by a DC non-following arc.

In one embodiment, the plasma heat source is located adjacent one or more air and / or steam inlet ports such that air and / or steam additives are injected into the path of plasma release of the plasma heat source.

In one further embodiment, the plasma heat source may be mobile, fixed, or a combination of both.

In one embodiment, the plasma heat used in the solid residue controller is provided by a DC non-following arc torch. In another embodiment, the plasma heat used in the solid residue controller is provided by a DC transitional arc torch.

Control system

In order to optimize the efficiency of the invention, a system is also optionally provided for controlling the operating conditions of the system according to the invention as well as the conditions under which the invention is carried out. If the end use of the gas product is to generate electricity, the control subsystem also provides optimum energy generation by ensuring that the gas composition and pressure are kept within acceptable limits of the gas engine / generator used to generate the electricity.

In one embodiment of the present invention, a control system may provide control of one or more processes performed by and / or performed by the various systems and / or subsystems described herein and / or affect the processes. It may provide control of one or more process equipment contemplated by. In general, a control system is associated with, and / or performed within, a system, eg, a gasification system, provided a system, subsystem, or component thereof, within or in connection with the various embodiments of the present invention. Various local and / or local processes associated with one or more of the overall processes can be operatively controlled, thereby adjusting various control parameters of the control system adapted to the effect of the process on the defined results. Accordingly, various sensing elements and reaction elements are distributed through the control system (s) or in connection with one or more components thereof, obtain various process, reactant and / or product properties, and achieve these properties with the desired results. It is used to react by implementing a change in one or more of the processes in progress through one or more controllable process equipment, and comparing it with a suitable range of the above characteristics that are helpful to.

In general, the control system detects one or more characteristics related to, for example, the system (s), process (s), inputs (s) provided therefor, and / or emissions (water) generated by the sensing element. One or more sensing elements. One or more computing platforms are communicatively coupled to the sensing element to evaluate representative characteristic values of the sensed characteristic (s), which ranges from a prescribed value to characterize suitable characteristics for the selected task and / or downstream result. And to calculate one or more process control parameters that help to compare the characteristic value (s) with and maintain the predetermined range of characteristic values. Thus, a number of reaction elements can be operatively connected to one or more process equipment that affects the system, process, inputs and / or emissions and is easy to adjust the sensed properties, and thus calculate the calculated process control parameter (s). And is communicatively connected to the computing platform (s) for evaluating and performing the process device (s).

In one embodiment, the control system provides feedback, feedforward and / or predictive control of various systems, processes, inputs and / or emissions associated with the conversion of the carbon containing feed to gas, thereby providing one or more processes performed in connection with the above. To promote efficiency. For example, various process characteristics may be evaluated and controllably adjusted to affect the process, which may include the calorific value and / or composition of the feed, the nature of the product gas (eg, calorific value, temperature, pressure, flow). , Composition, carbon content, etc.), the degree of change allowed for the property, and the value of the input cost-to-emissions. Heat source power, additive feed rate (s) (eg, oxygen, oxidants, steam, etc.), feed feed rate (s) (eg, one or more separate feeds and / or mixed feeds), gas and / or Or continuous and / or real-time adjustments to various control parameters, including but not limited to system pressure / flow regulators (eg, blowers, safety and / or control valves, flares, etc.), and the like. The characteristics can be performed in a manner that is evaluated and optimized according to the design and / or downstream application.

Alternatively, or in addition, the control system may be configured to monitor the operation of the various components of the provided system to ensure proper operation and, optionally, to ensure that the process (s) are carried out within the control standard upon application of the standard. have.

According to one embodiment, the control system can be further used to monitor and control the overall energy impact of the provided system. For example, provided systems can reduce or reenerge energy impacts, for example, by optimizing one or more of the processes performed by the system and again increasing the recovery of energy (eg, waste heat) generated by such processes. May be performed to be minimized. Alternatively, or in addition, the control system may be configured to adjust the composition and / or other properties (eg, temperature, pressure, flow, etc.) of the product gas generated through the control process (s), such as Not only are the properties suitable for downstream use, but they are also substantially optimized for effective and / or optimal use. For example, in embodiments in which the product gas is used to run a gas engine of a provided type for generation of electricity, the properties of the product gases can be adjusted such that these properties are optimally matched to the optimum input characteristics of the engine.

In one embodiment, the control system is configured to adjust the process provided to ensure that the reactant and / or product residence times in the various components, or limit or performance guidelines relating to the various processes of the overall process, are met and / or optimized. Can be. For example, the upstream speed can be controlled to substantially match one or more subsequent downstream processes.

In addition, in various embodiments the control system may be adapted for sequential and / or simultaneous control of various aspects of a provided process, in a continuous and / or real time manner.

In general, the control system may include any type of control system structure suitable for the application to be used soon. For example, the control system may comprise substantially a centralized control system, a distributed control system, or a combination thereof. Centralized control systems are generally suited to communicate with a variety of local and / or remote sensing devices and reactive elements each configured to sense various characteristics associated with the control process, and to directly or indirectly affect the control process. It will include a central controller configured to react through the above controllable process apparatus. Using a centralized structure, most of the calculations are performed centrally through a centralized processor or processors and most of the hardware and / or software needed to perform the control of the process is located at the same location.

Distributed control systems generally communicate with respective sensing elements and reaction elements that monitor local and / or local characteristics, respectively, and can react through local and / or local process equipment configured to affect local processes or subprocesses. It will include two or more distributed controllers. Communication may also occur between distributed controllers through various network types, where a characteristic sensed through the first controller may communicate with a second controller for a response therein, such a remote response being at a first location. This may affect the perceived characteristics in the system. For example, the characteristics of the downstream product gas can be sensed by the downstream monitoring device and adjusted by adjusting control parameters associated with the transducer controlled by the upstream controller. In a distributed architecture, control hardware and / or software may also be distributed among the controllers, where the same but modularly formed control scheme may be performed at each controller, or various cooperative control schemes may be performed at each controller. have.

Alternatively, the control system may be subdivided into separate, communicatively connected local, local and / or overall control subsystems. This structure allows a given process or series of interrelated processes to occur and can be controlled locally with minimal interaction with other local control subsystems. The overall master control system then communicates with each individual control subsystem to adjust the local processes necessary for the overall result.

The control system of the present invention may use any of the above structures, or any other structure commonly known in the art that is deemed to fall within the general scope and characteristics of the present specification. For example, a process controlled and performed in the context of the present invention may be controlled in a dedicated local environment, with any external communication with any central and / or remote control system used in the relevant upstream or downstream process, when applied. Can be. Alternatively, the control system may include subcomponents of the local and / or overall control system designed to cooperatively control the local and / or the overall process. For example, a module control system may be designed such that the control module interactively controls various subcomponents of the system while providing intermodule communication for local and / or overall control.

The control system generally communicates new or updated control parameters for one or more central networked and / or distributed processors, one or more inputs to accommodate flow sensing characteristics from various sensing elements, and various reactive elements. One or more output devices. One or more computing platforms of the control system may also include one or more local and / or remote computer readable media (eg, ROM, for storing various predetermined and / or readjusted control parameters, settings or desired system and process characteristic work ranges). RAM, removable media, local and / or network access media, etc.), system monitoring and control software, working data, and the like. Optionally, the computer platform may also have access to process simulation data and / or system parameter optimization and modeling means, either directly or through various data storage devices. In addition, the computing platform may include one or more arbitrary graphical user interfaces and input peripherals that provide management access to the control system (such as system upgrades, maintenance, changes, adaptations to new system modules, and / or equipment), as well as In addition, various arbitrary output peripherals (eg, modems, network connections, printers, etc.) may be equipped for communicating with data and information from external sources.

Any one of the process system, and subprocess system, may include hardware exclusively or any combination of hardware and software. Any combination of subprocess systems may have any combination of one or more proportional (P), integrated (I) or parallax (D) controllers, such as P-controllers, I-controllers, PI-controllers, PD controllers, PID controllers, and the like. It may include. The ideal choice of a combination of P, I and D controllers will depend on the dynamics and delay time of some of the reaction processes of the gasification system and the range of operating conditions for controlling the combination, and the dynamics and delay time of the combination controller. Will be obvious. The combination continuously monitors the value of the characteristic through the sensing element, and the specific value affecting each control element through which the monitoring value and the appropriate adjustment are made via the reactive element to reduce the difference between the observed value and the specific value. It will be apparent to those skilled in the art that the present invention can be performed in the form of analog wirings that can be compared with. It will be further apparent to those skilled in the art that the combination may be performed in a mixed digital hardware software environment. The additional effects of any optional sampling, data acquisition and digital processing are well known to those skilled in the art. P, I, D combination control may be performed with a feedforward and feedback control scheme.

In refinement or feedback control, the value of a control parameter or control variable monitored through a suitable sensing element is compared with a specific value or range. The control signal is determined based on the deviation between the two values, and a control element is provided to reduce this deviation. Conventional feedback or response control systems may be further adapted to include adaptation and / or prediction components, and the response to a given condition may be reactive to perceived properties while limiting potential excess in compensatory action. It will be appreciated that it may be customized according to the modeled and / or previously monitored response providing. For example, system and / or process characteristics in which acquired acquisition data and / or historical data for a given system configuration fall within the provided range from an optimal value adjusted to monitor the previous response and provide the desired results. It can be used to cooperatively adjust the response to. Such adaptation and / or predictive control schemes are well known in the art and are not considered to be outside the general scope and nature of the present invention.

Control components

Sensing elements contemplated in the context of the present invention as defined and described above include, but are not limited to, temperature and gas flow rate, gas pressure, height of the feed pile in the gasifier, gas composition and calorific value at specified locations throughout the system. It is provided to monitor one or more parameters that are not.

As defined and described above, the reaction components contemplated in the context of the present invention may comprise various control components operatively connected to a process-related device configured to affect a process provided by adjustment of control parameters provided in connection with the process. It may include, but is not limited thereto. For example, process equipment operable in the context of the present invention via one or more reaction components may include, but is not limited to, air and product gas blowers, feed inputs, pressure and temperature regulators, side transfer units, and plasma heat sources. It doesn't work. Thus, examples of operating conditions that can be adjusted by the reaction components of the control subsystem include the exchange-air flow rate (ie process air blower speed), feed input rate, ratio of feed input (eg high carbon feed). One or more of MSW relative to water, pressure of the system, movement of the lateral moving unit, input rate of process additives such as steam, and power to the plasma heat source.

In one embodiment of the invention, the control subsystem includes a temperature sensing element for monitoring the temperature of a location located throughout the system. The temperature sensing element for monitoring the temperature may be a temperature transmitter, for example a thermocouple or photothermometer, installed at a location in the system, as desired.

9 shows an overview of various means for monitoring and controlling temperature within a system, which illustrates where the temperature transmitter and flow regulator are installed throughout the system. For example, temperature transmitter 5982 is positioned to monitor the temperature of the product gas at gas-to-air heat exchanger product gas outlet 5926. Temperature transmitter 5981 is also positioned to monitor the temperature of the heated exchange-air 5015 at the exchange-air outlet 5917 of the gas-to-air heat exchanger 5109.

Temperature transmitters may also be located throughout the transducer to monitor the process temperature during the gasification and reconstitution process. For example, temperature monitoring in the area of the converter where the gasification process takes place ensures optimum conversion efficiency by keeping the feed pile at the highest possible temperature for as long as possible without reaching the temperature at which the feed melts or clumps. do. In order to stabilize the temperature required for the various stages of the gasification process, adjustments to the control valves 5994A, 5994B, and 5994C are carried out in the pile by adjusting the flow of the heated exchange-air to the provided area of the gasifier 2009. Temperature control is achieved. The temperature at the various stages is measured by temperature transmitters 5984A, 5984B and 5984C, respectively. Adjusting the temperature at various stages of the gasification process can also be achieved by controlled movement of the feed through the gasifier by the side delivery unit.

The temperature in the reconstruction zone 3009 of the transducer is monitored by temperature transmitter 5983. Power to the plasma torch 2980 may be adjusted as needed to stabilize the temperature of the reconstruction zone 3009 to maintain an optimal temperature for complete reconstitution of the offgas, volatiles, tar and soot to the desired gaseous products. have.

A temperature transfer device 5981 installed at the exchange-air outlet 5917 to measure the temperature of the heated exchange-air is performed under conditions that ensure that the heat recycle process is heated to a temperature suitable for use in the gasification process. To ensure that For example, if the optimum temperature of the exchange-air for use in the gasifier is about 600 ° C., a temperature transmitter installed in the air outlet stream may be provided to ensure that the temperature of the exchange-air does not exceed, for example, 625 ° C. Will be used. To avoid too much heated exchange-air (or too hot exchange-air) for a gasification process that can overheat the feed, control valve 5900 is opened to vent excess exchange-air to the atmosphere. .

Thus, means are also optionally provided for controlling the control valve 5590 for discharging exchange-air to the atmosphere. For example, in some instances, it is necessary to heat more air than is needed for the process due to equipment circumstances (eg when starting an interruption process). In this example, exchange-air can be released as needed.

According to one embodiment of the invention, the control strategy sets a fixed set point for an optimum heat exchange-air discharge temperature, for example about 600 ° C. In one such embodiment, even if the exchange-air flow through the gas-to-air heat exchanger is reduced, the exhaust gas temperature of the gas-to-air heat exchanger will remain the same. Thus, the reduced air flow through the gas-to-air heat exchanger exits the gas-to-air heat exchanger, increasing the temperature of the product gas entering the next step of the process, for example the heat recovery steam generator. However, if the airflow through the system is reduced, the product gas flow will also be reduced as a result and only the increased product gas input temperature for the heat recovery steam generator will be briefly high. For example, when the airflow is reduced to 50%, the maximum product gas input temperature observed briefly in the steam generator is about 800 ° C., which corresponds to the temperature range of the above invention.

Monitoring the temperature of the gas-to-air heat exchanger inlet can also ensure the temperature of the product gas such that each heat exchanger does not exceed the ideal working temperature of the device. For example, if the design temperature for a gas-to-air heat exchanger is 1050 ° C., the temperature data obtained from the temperature transfer device on the inlet gas stream for the heat exchanger may be exchanged through the system to maintain the optimum product gas temperature. It can be used to control both air flow rate and plasma thermal power. In addition, the measurement of the product gas temperature at the product gas outlet of the gas-to-air heat exchanger may be useful to ensure that the optimum amount of detectable heat is recovered from the product gas in the heat recovery step.

If the temperature of the gas venting converter exceeds a predetermined limit, this may indicate that the tube begins to plug at the point where the system should be stopped for maintenance. Thus, a heat exchanger having a port for convenient inspection and maintenance is provided as necessary.

In one embodiment of the present invention, the control subsystem includes a sensing element for monitoring pressure and gas flow rate through the gasification system. Such a pressure sensing element may comprise a pressure sensor, for example a pressure transducer, a pressure transmitter or a pressure tap, located in relation to a system on the vertical wall of the gasifier or a downstream component of the gasification system such as a gas storage tank. Can be.

Data relating to pressure and gas flow in the system is used by the control subsystem to determine whether adjustments to parameters such as torch power or rate of addition of solid residue material are needed.

In one embodiment of the present invention, the control subsystem includes a reaction component that adjusts the pressure within the system to maintain the desired pressure within the system within certain defined tolerances. For example, if the product gas blower speed or the exchange-air input speed is adjusted, any pressure change caused is corrected by adjustment to a particular working parameter as determined by the control subsystem.

10 shows an overview of various means for monitoring and controlling product gas pressure and flow through the system. The pressure transmitter 7095 on the downstream gas storage tank 7010 signals the exchange-air flow control valve at the transducer 1010, whereby, for example, a decrease in gas storage tank pressure signals the gas. It increases the exchange-air flow to the firearm 2010 and vice versa. Exchange-air flow to gasifier 2010 is controlled using control valves 5994A, 5994B, and 5994C. The increased amount of exchange-air 5015 delivered to the gasifier 2010 increases the rate at which the feed is gasified, thereby generating an increased product gas 5020 flow (and an increase in system pressure).

Any change in the demand for exchange-air 5015 in the gasifier 2010 affects the process air blower discharge pressure as measured by the pressure transmitter 5095 and then the process air blower 5012. The speed is adjusted in a variable frequency drive (VFD). The speed of the process air blower 5012 is increased when low pressure is detected in the storage tank 7010, and the speed is decreased when high pressure is detected in the storage tank. If an increased amount of gas is produced, the control subsystem can also automatically adjust the speed on the gas blower VFD to reduce the pressure increase, and more gas is delivered to the storage tank to increase the storage tank pressure.

In response to data obtained by a pressure sensor located through the system, the speed of the downstream induction blower increases or decreases the pressure in the system (and thus the speed of the fan), thereby increasing the speed of the fan. It is adjusted according to whether or not. In one embodiment, data relating to pressure at points throughout the system is obtained on a continuous basis, such that the control subsystem frequently adjusts the fan at a rate that maintains system pressure within a predetermined set point. do.

In one embodiment, the system is maintained under some negative pressure relative to atmospheric pressure to prevent the gas from escaping into the environment.

In one embodiment, the internal pressure is adjusted using an induction blower located downstream of the gasifier that acts by pulling the product gas from the outside of the gasifier. Thus, the induction blower used maintains the system at atmospheric pressure or a pressure lower than that. In one embodiment, a control valve is provided in the gas outlet line that increases or restricts the flow of gas removed by the downstream gas blower.

In a system where the positive pressure is maintained, the blower is operated to reduce or stop the removal rate of the produced gas, so that the gas is pushed out throughout the system to generate a higher (plus) pressure.

Fluctuations in gas flow can occur as a result of non-uniform conditions (eg, malfunction of the torch, blockage of the gas line, or disturbance of feed input) in the gasification process. If fluctuations in the gas flow persist, the system can be stopped until this problem is resolved.

Since addition of high carbon feed, air and / or steam process additives during the gasification process can affect the conversion chemistry, it is desirable to monitor the product gas composition. In one embodiment of the invention, the control subsystem comprises a sensing element for monitoring the composition of the product gas. Monitoring the composition of the product gas can be achieved, for example, by a gas analyzer. The gas analyzer can, for example, determine the hydrogen, carbon monoxide and / or carbon dioxide content of the product gas. One method that can be used to determine the chemical composition of the product gas is through gas chromatography (GC) analysis. Sample points of this analysis can be located throughout the system. In one embodiment, the gas composition is measured using a Fourier Transform Infrared (FTIR) analyzer that measures the infrared spectrum of the gas.

Although hot gas analyzers exist, the composition is generally measured after the product gas is cooled and subjected to a control step to remove particulate matter and other contaminants.

The product gas composition can be controlled by adjusting the composition of the gasified feed (eg, the ratio of MSW to HCF), as well as the amount of air and / or steam process additives added to the gasification and reconstitution reaction. Thus, the control subsystem provides a means for controlling the ratio of MSW to HCF, the rate of addition of the feed stream, as well as the amount of air and / or steam process additives added to the converter.

In one embodiment of the invention, the control subsystem comprises means for adjusting the speed and / or amount of air input to the gasifier and / or the reconstructor. In one embodiment of the invention, the control subsystem comprises means for adjusting the speed and / or amount of steam input to the reconstructor.

In one embodiment of the invention, the control subsystem comprises means for adjusting the rate of addition of the high carbon feed (HCF) input to the gasifier in response to the process required for the high carbon input or the low carbon input to provide the desired gas composition. Include.

In one embodiment of the invention, the control subsystem comprises means for adjusting the rate of addition of the MSW to the gasifier. MSW and optionally HCF dosing are added to the gasifier using a number of possible dosing means selected and adapted as needed for the type of material to be added. The material may be added in a continuous manner, for example using a rotating screw or auger mechanism. Alternatively, the material may be added in a discontinuous manner, for example using a pusher ram to add the material in the required proportions.

In one embodiment, the feed dosing speed is controlled by adjusting the feed screw carrier speed via a drive motor variable frequency drive (VDF). The dosing rate will be adjusted as needed according to the heating capacity of the heated exchange-air dosing.

The system may further comprise means for monitoring and controlling the pile height (or level) to maintain stable process conditions in the transducer. This provides the ability to maintain a stable dummy height in the transducer. Adjusting the pile height prevents fluidization of material from exchange-air injections that can occur at low levels, and also prevents poor temperature distribution through the pile resulting from limited airflow that can occur at high levels. Maintaining a stable dummy height also ensures a constant transducer residence time.

A series of level switches in the gasifier measures pile depth. In one embodiment, the level switch is a microwave device having an emitter on one side of the gasifier and a receiver on the other side that detects the presence or absence of solid matter at a point in the transducer.

In one embodiment of the present invention, a lateral movement unit is provided for moving a gasified substance through various regions of the gasifier. The amount and location of the feed in the gasifier is a function of the feed rate and movement of the lateral movement unit, as well as the heated exchange-air input. Thus, in this embodiment, the control subsystem includes means for controlling the movement of material through the various regions of the gasifier as needed.

In one embodiment, the lateral movement unit is a ram and the feed is carried through various regions of the gasifier at a speed determined by stroke length and frequency. For example, the control subsystem utilizes each stroke using other means of reciprocating control, such as a limit switch or a computer controlled variable speed motor drive to control the length, speed and / or frequency of the ram stroke. The amount of material moved by can be controlled.

In one embodiment, the lateral movement unit comprises one or more screw conveyers, wherein the rate of movement of the material through the gasifier is controlled by adjusting the conveyer speed via a drive motor variable frequency drive.

In one embodiment of the invention, the control subsystem comprises a power for the plasma heat source, and optionally means for adjusting the position. For example, if the temperature of the product gas at the gas outlet of the converter is too high, the control subsystem may reduce the power rating of the plasma heat source.

Use / Process of Gasification System

The system according to the invention generally gasifies the feed using a gasification process of the feed comprising passing the feed through a converter adapted to the heating effect of the heated exchange-air. After heating with exchange-air, the feed is dried and the volatile components in the dried feed are volatilized. In one embodiment of the invention, the heated exchange-air further activates the complete conversion of the resulting char to its gaseous component and leaves ash by-products. The combination product of the drying, volatilization and combustion stages produces emissions, which are further applied to the heat from the plasma heat source, which releases the emissions to carbon monoxide, carbon dioxide, hydrogen, water vapor (and nitrogen due to the use of air in the gasification process). Convert to a hot gas product comprising a. Steam and / or air process additives may optionally be added in the gasification step and / or in the offgas conversion step.

In one embodiment of the invention, the process further comprises subjecting the byproduct to heating by a second plasma heat source to form a slag product.

The process of the present invention comprises passing a hot gas product through a heat exchanger, transferring heat from the hot product gas to air to produce heated exchange-air and cooled product gas, and heating in gasification of the carbon-containing feed. Using the exchange-air that has been adapted.

The process of the present invention further includes passing the cooled gas product to a second heat exchanger, transferring heat from the first cooling gas to water to produce further cooled gas and steam.

The process of the present invention maximizes net conversion efficiency by generating heat to run the gasification process, running the rotary machine, and subtracting the amount of electricity that must be consumed to power the plasma heat source. For applications aimed at generating electricity, efficiency compares the amount of energy generated by using the product gas with the energy consumed by the entire gasification process (eg in powering a bin or in fuel cell technology). It is measured by means of recoverable heat recovery that generates steam for powering the steam turbine.

The gasification process includes the amount of power supplied to the plasma heat source based on one or more of the feed dosing rate, exchange-air flow rate, product gas flow rate, steam process additive input rate, and flow rate / pressure, and the temperature of the product gas and And / or a feedback control step of adjusting one or more of the compositions. Thus, the feedback control step enables the flow rate, temperature and / or composition of the synthesis gas to be maintained within an acceptable range.

In one embodiment of the invention, the process further comprises preheating the carbon containing feed prior to adding to the converter.

In one embodiment, the gasification process according to the present invention utilizes the use of exchange-gas for heating the gasifier to a temperature suitable for gasifying the feed. In another embodiment conventionally used in the initiation phase of the system, air is supplied to the system, which can thus be heated using heat recovered from plasma heat or other steps in the gasification process to produce a hot initiation gas. Which then enters the gas-to-air heat exchanger to generate heated exchange-air. Exchange-air is moved to the exchange-air inlet to heat the gasifier, and the entire process can be run without the use of fossil fuels.

11A-11I illustrate various options for recycling heat in accordance with the present invention.

11A is a process flow diagram describing one embodiment of the present invention, wherein hot product gas 5020A is generated by gasifying a carbon-containing feed in converter 1000A. The hot product gas 5020A is passed through a heat exchanger 5100A, and heat is passed from the hot product gas 5020A to produce heated exchange-air 5015A and cooled product gas 5025A. 5012A) to the blown air 5010A through the heat exchanger. The heated exchange-air 5015A is then passed back to converter 1000A to start the gasification process. Thereafter, the cooled product gas 5025A is further cooled by a dry quench step 6111A before passing through the gas conditioning system 6000A. The generated gas after cooling and washing is then burned in the gas engine 5060A, and the hot combustion gas 5051A is exhausted to the atmosphere.

FIG. 11B is a process flow diagram describing one embodiment of the present invention, wherein hot product gas 5020B is generated by gasifying a carbon containing feed in converter 1000B. The hot product gas is passed through heat exchanger 5100B, and heat is passed from the hot product gas 5020B to the air blower 5012B to produce heated exchange-air 5015B and cooled product gas 5023B. By air to the blown air 5010B. The heated exchange-air 5015B is then passed back to converter 1000B to start the gasification process. Additional heat is recovered from the cooled product gas 5023B by passing the product gas through a heat recovery steam generator 5300B before passing through the gas conditioning system 6000B. Additional heat is transferred to water 5030B, producing steam 5035B. After cooling and washing, the product gas is then combusted in gas engine 5060B and hot combustion gas 5051B is exhausted to the atmosphere.

FIG. 11C is a process flow diagram describing the embodiment of FIG. 11B wherein hot combustion gas 5051B from a gas engine is passed through a second heat recovery steam generator 5300C, and heat from the hot combustion gas is reduced to water ( 5030C) to generate steam 5030C.

FIG. 11D is a process flow diagram describing the embodiment of FIG. 11B in which steam 5035B generated in heat recovery steam generator 5300B is used to power a steam turbine 5065D that generates electricity.

FIG. 11E is a process flow diagram describing the embodiment of FIG. 11C, wherein steams 5035B and 5035C generated in heat recovery steam generators 5300B and 5300C are combined to power a steam turbine 5065E that generates electricity. And is used.

FIG. 11F is a process flow diagram describing the embodiment of FIG. 11B wherein the heated exchange-air 5015B is also fed to predry the feed 5088F before being fed to the converter 1000B for gasification. Passed to controller 5067F.

FIG. 11G is a process flow diagram describing the embodiment of FIG. 11B wherein steam 5035B generated in the heat recovery steam generator 5300B is used to indirectly heat the feed controller 5067G and thereby for gasification. Feed 5088G is pre-dried before being fed to converter 1000B.

FIG. 11H is a process flow diagram describing one embodiment of the present invention, wherein hot product gas 5020H is generated by gasifying a carbon containing feed in converter 1000H. The hot product gas 5020H is passed through a heat exchanger 5100H, and heat passes from the hot product gas 5020H to an air blower (5015H) to produce heated exchange-air 5015H and cooled product gas 5025H. 5012H) to the blown air through the heat exchanger. The heated exchange-air 5015H is then passed back to converter 1000H to start the gasification process. The cooled product gas is then passed through a gas conditioning system. After cooling and washing, the product gas is then combusted in gas engine 5060H, and hot combustion gas 5051H is exhausted to the atmosphere. This embodiment includes a solid residue control step, where the hot gas produced at the solid residue controller 4020H is also passed through the heat exchanger 5105H, and heat from the hot gas is passed through the heat exchanger 5105H. It is delivered to air 5210H that is blown through to produce a second heated air product 5115H. Second heated air product 5115H is then used to indirectly heat feed controller 5067H, whereby feed 5088H is pre-dried before being fed to converter 1000H for gasification.

11I is a process flow diagram describing one embodiment of the present invention, wherein hot product gas 5020I is generated by gasifying a carbon containing feed in converter 1000I. The hot product gas 5020I is passed through a heat exchanger 5100I, and heat passes from the hot product gas 5020I, to produce heated exchange-air 5015I and cooled product gas 5025I. 5012I) to the blown air through the heat exchanger. The heated exchange-air 5015I is then passed back to converter 1000I to start the gasification process. The cooled product gas 5025I is then passed through gas conditioning system 6000I and into a system for storing and homogenizing gaseous product 7000I. Subsequently, a portion of the product gas 5125I is combusted in the gas engine 5060I and the hot combustion gas 5051I is exhausted to the atmosphere, while another part of the product gas 5125I is combusted in the gas burner 5067I. Generates heat to preheat the converter 1005I of another gasification system.

The invention will now be described with reference to specific examples. It is to be understood that the following examples are intended to illustrate embodiments of the invention and are not intended to limit the invention in any way.

In general, the system of the present invention is used by supplying exchange-air to a converter in which the feed is applied to sufficient heat to cause the gasification reaction to occur.

In the exemplary embodiment shown in FIGS. 12 and 13, each of the gasifiers 2100 and 2200 has a staircase layer with three levels or stages. Optionally, each layer level is inclined from about 5 to about 10 degrees. In a stage-bed gasifier, individual stages (layer level) provide suitable conditions for each drying, volatilization, and char-to-reconversion stage of the gasification process, thereby optimizing the gasification process.

In each of these exemplary gasifiers, the feed is fed to the first stage, where conditions are provided along with some volatilization and char-to-reconversion to make the main process dry. The normal temperature range of this stage (measured at the bottom of the pile of materials) is 300 to 900 ° C.

The dried feed is then moved to a second stage, where the main process, with a small scale (rest) drying operation as well as some char-to-reconversion, causes the volatilization of the dried feed to form char. Conditions are provided. The normal temperature range of this step is 400 to 950 ° C.

The char is then moved to a third stage where conditions are provided such that the main process is char-to-reconversion with less volatilization (rest). The normal temperature range is 600 to 1000 ° C.

Movement over the steps is facilitated by the lateral moving units, each step being provided by a lateral moving unit which is optionally controlled independently.

In the embodiment of the gasifier shown in FIG. 12, the gasifier 2100 has a refractory lined horizontally oriented gasification with a feed inlet 2104, a gas outlet 2106, and a solid residue outlet 2108. Chamber 2102. Gasification chamber 2102 has a stepped layer with multiple floor levels 2112, 2114 and 2116. Each layer level has a series of exchange-air inlets 2126 located on the sidewall adjacent to the layer level to allow addition of exchange-air. The input of exchange-air is adjusted to promote gasification of the reactants.

In the embodiment of the gasifier shown in FIG. 13, the gasifier 2200 has a refractory lined horizontally oriented gasification with a feed inlet 2204, a gas outlet 2206, and a solid residue outlet 2208. Chamber 2202. Gasification chamber 2202 has a stepped layer with multiple floor levels 2212, 2214, and 2216.

Each level or step has a perforated layer into which heated air can be introduced. The air supply for each level or stage is independently controllable. Independent air supply and distribution through the perforated layer 2270 is achieved by separate air boxes 2272, 2274 and 2276 forming layers in each step.

An exemplary air box is illustrated in FIG. 14, which clearly shows the perforated top plate 2302 of the air box as well as the connecting flange 2280 for connection to the exchange-air conduit system.

The offgas formed in the gasifier is then further processed in a reconstitution chamber with a plasma heat source and optionally steam and further heated exchange-air. These additives are added in a reconstitution step to ensure the formation of product gases, optionally having a defined composition. The temperature during the reconstitution step is maintained at a temperature range high enough to maintain the reaction at an appropriate level to ensure complete conversion to the defined gas product while minimizing contaminant products. In an exemplary embodiment, the temperature range of the reconstitution step is about 900 ° C to about 1300 ° C.

After the reconstitution step, if the temperature of the product gas is too high, steam is optionally added to reduce the exhaust temperature of the product gas. The product gas exits the plasma reconstruction zone at a temperature of about 900 ° C to about 1100 ° C. In an exemplary embodiment, the product gas exhaust temperature is about 1000 ° C +/- 100 ° C. The flow rate of the hot product gas is from about 6000 Nm ³ / hr to about 9500 Nm ³ / hr, typically about 7950 Nm ³ / hr. The hot product gas is then passed to a gas-to-air heat exchanger.

In this embodiment, the air enters the gas-to-air heat exchanger at ambient temperature, ie from about −30 to about 40 ° C. Air circulates through the system using an air blower and enters the gas-to-air heat exchanger at a rate of about 1000 Nm ³ / hr to 5150 Nm ³ / hr, typically about 4300 Nm ³ / hr.

In this embodiment, the air is heated in a heat exchanger that produces exchange-air having a temperature of about 500 ° C to about 625 ° C. In an exemplary embodiment, the exchange-air temperature is about 600 ° C. The hot product gas is in turn cooled to a temperature of about 500 ° C to about 800 ° C. In an exemplary embodiment, the product gas temperature is about 740 ° C. The heated exchange-air is passed through the exchange-air inlet to the gasifier to gasify the feed as discussed above.

The gas-to-air heat exchanger of an exemplary embodiment is a shell-tube heat exchanger specially designed to load high levels of particulates into the product gas, where the product gas flows on the tube side and air flows countercurrently on the shell side.

In an exemplary embodiment, the cooled product gas is further cooled using a dry quench step to remove excess heat from the product gas, thereby generating the cooled product gas required for subsequent filtration and conditioning steps. The cooled product gas is then further passed through a gas conditioning step to remove acid gases, heavy metals, particulate matter and other contaminants.

Residue by-products of the gasification process are dissolved into a dedicated plasma heat source and further controlled in the residue control chamber. The product of the residue control step is an inert slag material and a hot gas.

While the invention has been described with reference to specific embodiments, it will be apparent to those skilled in the art that various modifications may be made without departing from the spirit and scope of the invention as set forth in the appended claims.

The descriptions of all patents, publications, and database listings, including published patent applications referred to herein, are to the same extent as each and each individual patent, publication, and database listing are specifically and individually designated as being incorporated by reference. The entire contents are specifically incorporated by reference.

Claims (10)

A system for recycling heat recovered from a hot gas to a carbon-containing feed gasifier, Means for delivering hot gas to a gas-to-fluid heat exchanger, the means for transferring heat from the hot gas into the fluid to produce heated fluid and cooled gas; Means for delivering the heated fluid to the gasifier; And A control system comprising a sensing element for monitoring operating parameters of the system and a reactive element for adjusting operating conditions within the system to optimize the gasification process, The reaction element adjusts the operating conditions in the system according to the data obtained from the sensing element to contain carbon recovered from the hot gas, optimizing the efficiency of the gasification process by maximizing energy generation while minimizing the energy consumption of the process. A system for recycling to a feed gasifier. The system of claim 1, wherein the hot gas is a gas generated during the carbon containing feed gasification process. The system of claim 2 wherein the fluid is air, water, oil, nitrogen or carbon dioxide. 4. The system of claim 3, wherein the fluid is air and the gas-to-fluid heat exchanger is a gas-to-air heat exchanger. 4. The system of claim 3, wherein the fluid is water and the gas-to-fluid heat exchanger is a heat recovery steam generator. A system for recycling heat recovered from a hot gas to a carbon-containing feed gasifier, Means for delivering hot gas to a gas-to-air heat exchanger, the means for transferring heat from the hot gas to air to produce heated air and cooled gas; And A system for recycling heat recovered from the hot gas to a carbon-containing feed gasifier comprising means for delivering heated air to the gasifier. The system of claim 6, wherein the hot gas is a gas produced in a gasifier during the carbon containing feed gasification process. 7. The hot gas conduit system of claim 6, wherein the means for delivering hot gas to the gas-to-air heat exchanger provides fluid communication between the hot gas outlet on the gasifier and the hot gas inlet on the gas-to-air heat exchanger. Wherein the means for delivering the heated air to the gasifier comprises an air conduit system providing fluid communication between an air outlet on the gasifier and an air outlet on a gas-to-air heat exchanger, the hot gas being a gasifier And from the gas-to-air heat exchanger through the hot gas conduit, the heated air from the gas-to-air heat exchanger to the air inlet of the gasifier through the air conduit system. Detectable heat from the hot gas produced by the gasification process uses a gas-to-fluid heat exchanger comprising a hot product gas inlet in communication with the cooled product gas outlet and a cooling fluid inlet in communication with the heated fluid outlet. A method of improving the efficiency of the gasification process of a carbon-containing feedstock by recycling it back to the gasification process, Moving the hot product gas through a hot product gas inlet to a gas-to-fluid heat exchanger; Moving the cooling fluid through the cooling fluid inlet to a gas-to-fluid heat exchanger; Heat from the hot product gas is transferred to the cooling fluid through a gas-to-fluid heat exchanger to exit the cooled product gas exiting the heat exchanger through the cooled product gas outlet, and the heat exchanger through the heated fluid outlet. Generating an exiting heated fluid; And Providing heat for the gasification process of the carbon containing feed using the heated fluid. 10. The method of claim 9, wherein the fluid is air and the gas-to-fluid heat exchanger is a gas-to-air heat exchanger.

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