WO2000062592A2

WO2000062592A2 - Method and apparatus improving the efficiency of a steam boiler power generation system

Info

Publication number: WO2000062592A2
Application number: PCT/IB2000/001124
Authority: WO
Inventors: Stephen Mongan
Original assignee: Stephen Mongan
Priority date: 1999-03-30
Filing date: 2000-03-30
Publication date: 2000-10-26
Also published as: WO2000062592A3

Abstract

An apparatus and method for recovering heat from waste fluids and gases and for improving the combustion of hydrocarbon fuels and the heat transfer within a steam boiler. The apparatus comprises a controller, a distribution manifold, a plurality of heat recovery modules and a plurality of magnetic ionization modules. The apparatus possesses the ability to monitor steam demands within a building and to respond by matching the demands with the most cost effective steam supply source. The plurality of the heat recovery modules includes a flue heat recovery module. The plurality of magnetic ionization modules includes a fuel magnetic ionization module and a water magnetic ionization module for charging fuel molecules to effect a more complete and efficient combustion and for charging the mineral molecules in water to prevent crystallization respectively.

Description

METHOD AND APPARATUS IMPROVING THE EFFICIENCY OF A STEAM BOILER POWER GENERATION SYSTEM

This application claims the benefit of U.S. Provisional Application No. 60/126,972 filed on March 30, 1999, which is herein incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to a method and apparatus for improving the heat transfer and control of a steam boiler power generation system. More particularly, this invention relates to a system and method that incorporates a controller, a distribution manifold, and a plurality of heat recovery modules and magnetic ionization modules for recovering heat from waste fluids and gases and for improving the combustion of hydrocarbon fuels.

BACKGROUND OF THE INVENTION

Currently, it is estimated that space heating, water heating and industrial process heating account for 40% of all energy consumption in the industrialized nations. Furthermore, over 70% of this energy is currently provided by a limited supply of hydrocarbon fuels. In order to conserve and maximize the benefits of these resources, it is necessary to increase the thermal efficiency of the heating processes.

Applying today's advanced technology has unleashed the full potential of steam, a highly reliable and effective form of heating. With modern control systems, steam is unmatched in its ability to efficiently convey heat. Fuel burning in a single centralized plant is more easily controlled, resulting in higher combustion efficiency and lower emissions. Centralized steam plants avoid the problems of local noise and polluting emissions arising from decentralized systems such as gas-fired systems. Steam is an excellent carrier of heat, requiring only small bore pipes which lose less heat than larger pipes of hot water and thermal oil systems. This results in less costly pipe work and easier installation. Heat loss is minimized even further by the use of modern pipe insulation. Moreover, steam is pure water in vapor form. Therefore, it is environmentally friendly and inherently safe in hazardous areas (no risk of sparks and no flammable gas or flames). Efficient modern lagging materials and techniques mean steam can be safely used in all environments. Steam is sterile and can be directly injected for cooking and sterilizing processes.

Traditionally, many of the processes and techniques for creating steam generate an enormous amount of waste fluids and gases. These byproducts are often simply discharged into the environment without treatment. Generally, these waste products retain a large quantity of energy in the form of heat which, upon release, contributes to the problem of global warming. The waste heat is also indicative of the thermal inefficiency of these processes and the lack of a heat recovery mechanism. Since the middle of the 18th century there have been certain milestones in the development of steam boilers. The generic term for such boilers is shell boilers. Shell boilers operate by passing heat through tubes in the boiler, which in turn transfer heat to the surrounding boiler water. There are several different combinations of the tube layout for shell boilers, involving the number of passes the heat from the boiler furnace will usefully make before being discharged. A typical arrangement can be seen in Figures 8a and 8b which show a two pass boiler configuration where the heat from the furnace is reversed to flow along the second pass. Figure 8a shows a dry back boiler where the heat flow is reversed by a refractory lined chamber on the outer plating of the boiler. A more efficient method of reversing the heat flow is through a wet back boiler configuration, as shown in Figure 8b. The reversal chamber is contained entirely within the boiler which allows for a greater heat transfer area, as well as allowing the boiler water to be heated at the point where the heat from the furnace will be hottest - on the end of the chamber wall.

Another shell boiler (a Lancashire boiler seen in FIGs. 9a and 9b) was set in a brickwork foundation called a setting which was arranged in order to improve the thermal efficiency. The hot gases, somewhat reduced in temperature, (but still quite hot), left the backend of the boiler, and were diverted downward and under the boiler through a brickwork duct, which was part of the boiler setting, transferring heat through the bottom of the boiler shell to the water. At the front of the boiler the hot gas stream was divided, and the two streams were diverted up to pass back round the sides of the boiler (see FIG. 9b). This was accomplished by the two ducts provided round the sides of the boiler, built into the brick setting. These two side ducts met at the back of the boiler and fed into a chimney (not shown). These passes were an attempt to extract the maximum amount of energy from the hot product gases before they were released to the atmosphere. The gas stream, after the third pass, passes through the economizer into the chimney. The economizer heats the feed water and results in an improvement in thermal efficiency.

One of the disadvantages of the Lancashire boiler was that repeated heating and cooling of the boiler, with the resultant expansion and contraction that occurs, upset the brickwork setting and ducting. This resulted in the infiltration of air, which upset the furnace draught. They are also very expensive to produce, due to the large amounts of material used and the labour required to build the brick setting.

The Economic boiler shown in FIG. 10 was an improvement on the Lancashire boiler. It had a cylindrical outer shell containing two large-bore flues, into which were set the furnaces (not shown). The hot flue gases passed out of the furnace flues at the back of the boiler into a brickwork setting (dry back) and were deflected through a number of small-bore tubes arranged above the large-bore furnace flues. These small bore tubes presented a large heating surface to the water. The flue gases passed out of the boiler at the front and into an induced draught fan which passed them into a chimney. The two pass economic boiler was only about half the size of an equivalent Lancashire boiler and it had a higher thermal efficiency. A further development of the economic boiler was the creation of a three pass wet back boiler (shown in Figure 11) which is a configuration in use today. The improvement of materials and manufacturing processes meant that more tubes could be accommodated within the boiler. Early in its development the basic boiler was long and required a large boiler house area. By forcing the hot gases to go backwards and forwards through a series of tubes, the boilers were designed to be shorter, and heat transfer rates were improved. The modern multi-tubular packaged boiler is the present state of the art. The packaged boiler is so called because it comes as a complete package. Once delivered to site it requires only the steam, water and blowdown pipe work, fuel supply and electrical connections to be made for it to become operational. These boilers are classified by the number of passes - the number of times the hot combustion gases pass through the boiler. The combustion chamber is taken as the first pass. The most common boiler is a three pass unit as shown in Figure 12 with two sets of fire-tubes and the exhaust gases exiting from the back end of the boiler.

However, various inefficiencies exist in these boilers. Inefficiencies begin at the boiler feed tank sometimes known as the hot well. A feed tank is widely recognized as being the meeting place for cold make-up water and condensate return. Due to the vast number of industrial processes, the mix at the feedtank can be between 100% make up to almost 100% condensate return. It is important that the feed tank be kept at reasonably high temperature in order to prevent corrosion of the boiler and steam plant caused by dissolved oxygen and other gases. These gases are readily absorbed by cold water but expelled upon heating typically around 85°C/185°F. By heating the feed water, the amount of scavenging chemicals subsequently required can be reduced significantly. The feed water must also be heated to prevent any thermal shock the boiler may undergo when cold water is introduced to the hot surfaces of the boiler internals. In most cases the feed tank will have some form of heater to pre-heat the boiler feed water prior to delivery. This is usually in the form of steam lance injection and consumes a considerable amount of energy. Since the feed tank is hot, steps must be taken to minimize heat loss. Boilers and the associated firing equipment should be designed for efficient operation, and also be properly sized. A boiler which has to cope with a peak load above its maximum continuous rating, will operate at reduced efficiency. Pressure may drop and the resultant priming and carryover will mean the boiler is incapable of providing good quality steam when required. Conversely, if a boiler has to work at a small percentage of its rating, then radiation losses can become significant, and, again there is a drop in overall efficiency. It is not easy to match boiler plant to what is often a variable steam load. Two or more boilers are more flexible than a single unit which explains the common arrangement of a larger boiler for the winter load and a small boiler for the summer load. The boiler is only part of an installation. It is just as important to have firing equipment which will respond to the load but maintain the correct fuel/air ratio. The major losses in any boiler are represented by the hot gases discharged at the chimney. If combustion is good, there will only be a small amount of excess air. The exhaust gases will contain a relatively large percentage of carbon dioxide and only a small amount of oxygen. At the same time, if the heating surfaces are clean, a high percentage of heat will be extracted and the exhaust gas temperatures will be low. If combustion is poor, with a lot of excess air, then the increased weight of the exhaust gases will contain a reduced percentage of carbon dioxide and increased amount of oxygen. If the burning rate is high or the heating surfaces are dirty, it will not be possible to extract such a high percentage of heat and exhaust gas temperatures will rise.

Boilers are designed to operate at relatively high pressures. This means that small steam bubbles will be released at the water surface giving good quality dry steam. If the pressure is allowed to fall, for whatever reason, then the bubble size will increase, resulting in turbulence, priming and carryover. For this reason, boilers must be operated at the correct pressure.

Furthermore, furnaces and boilers are typically powered by the well known process of combustion of hydrocarbon fuels. However, the efficiency of the combustion process is affected by a variety of different factors. First, the combustion of hydrocarbon fuels such as natural gas involves the process of oxidation, accompanied by the production of heat and light. The efficiency of the combustion process is generally gauged by the production of the byproducts carbon dioxide CO_a and carbon monoxide CO. When an adequate and uniform supply of oxygen is present, CO₂ is formed to the exclusion of CO. It is generally recognized that when one pound of carbon is burned into CO instead of CO₂, a quantity of heat approximately 10,000 Btu (British thermal unit) is lost. Thus, a lack of uniform oxygen supply affects oxidation, thereby reducing the efficiency of the combustion process. Second, the presence of an adequate oxygen supply alone may not necessarily increase the efficiency of the combustion process. Specifically, the orientation of the fuel molecules also contributes to the affinity between the carbon and oxygen atoms, thereby affecting the formation of C0₂ Furthermore, a typical problem of any water system is the accumulation of scale on the inner surfaces of metal pipes, tanks, and boiler. The scale is a deposit of carbonate salts formed by water containing dissolved calcium and magnesium salts, or ferrous iron, which serve as electrolytes. Furthermore, the dissimilar metals in our water system such as copper, steel, brass and aluminum act as electrodes when they are in contact with water. When an electrolyte is dissolved in water, the solution conducts electricity in the presence of two electrodes having different oxidation potentials.

Over the years, various heat recovery systems have been developed to address these problems. Examples of such systems are described in U.S. patent 4,699,315 issued on October 13, 1987 to White, U.S. patent 4,621,681 issued on November 11, 1986 to Grover and U.S. patent 4,136,731 issued on January 30, 1979 issued to Deboer.

White discloses a system for recovering heat from a chimney by incorporating a heat recovery unit on top of the chimney. The system recovers the heat by heating water which is returned to a heat exchanger for heating a conditioned space within a building. However, this simple system lacks the important ability to detect and monitor energy loading from different parts of the building and also lacks the ability to channel the recovered heat to meet different energy needs within the building. Grover discloses a system for recovering heat from waste gases of a boiler by using a plurality of heat pipes in combination with a steam boiler. The recovered heat is converted into heated water or heated steam. Again, this system lacks the important ability to detect, monitor and satisfy the energy loading from different parts of the building. DeBoer discloses a heat transfer system for recovering heat from the flue of the furnace. The system incorporates a heat exchanger disposed within the flue of the furnace where recovered heat in the form of heated water is supplied to the water heater and a fan chamber for supplementing the furnace heating operation. The system incorporates a seasonal switch, timer, and thermostats for controlling the movement of the recovered heated water. However, the system still lacks the ability to detect, monitor and satisfy the energy loading of the building, such as matching the most cost effective power generation source with a particular demand at a particular time. In fact, the heat recovery system of DeBoer only operates seasonally.

Therefore, a need exists in the art for a system and method that incorporates heat recovery in combination with load matching controls, for improving the thermal efficiency of a boiler power generation system and to reduce the potential corrosive properties of dissolved gases in feed water other than by chemical additives. SUMMARY OF THE INVENTION

The apparatus of the present invention comprises a steam generation system of a boiler with a plurality of heat transfer sections, a controller and a plurality of ionization modules. The system transfers heat through its various sectors to maximum thermal efficiency, improves the combustion of hydrocarbon fuels and improves the heat transmission through the primary steam generation section. The system possesses the ability to improve the 'from and at' rating widely used by steam boiler manufacturers and known industry standards by definition of the feed water temperature being lifted to circa 120°C without further additional heat such as a steam lance (injector). The system also possesses the ability to monitor steam loading within a building or process and to respond by matching the demand with the most efficient and cost effective steam power generation source. The system of the present invention is adapted to a building or process that requires steam for a plurality of applications such as heating, cooking, hot water, and the like.

The controller incorporates a processor, a display, an energy meter and a plurality of sensors. The plurality of sensors are disposed along the multitude of circuits and locations that dictate demand and the current available heat sources within the heat transfer process, together with the temperature of water make-up and all condensate return into the boiler feed tank (hot well).

The sensors are electrically coupled to the processor which is programmed to record the measurements and to deduce, the most efficient sequence to meet the loading of the building or process. If the processor detects or anticipates a disparity in the loading, the controller will activate the appropriate firing sequence to meet the demand. The present invention encompasses first law thermodynamics (energy cannot be created or destroyed only exchanged), in that all of the energy used in the combustion of a given fossil fuel will be used in each of the plurality of stages to produce steam at a pre-controlled pressure. The total enthalpy is achieved by a design that incorporates not only advanced heat transfer characteristics through its heat pipe application but can be infinitely modulating through its burner and combustion air configuration. The design allows for the controller to match the demand for the ultimate process that requires steam (mass flow and pressure) which in turn determines the total enthalpy at the point of use, and therefore by definition the boiler output and input. For description purposes the flow chart shows the steam requirement process to be an industrial laundry. The present invention has a heat transfer device that is considerably smaller in physical size to that of the current art due to the application of a plurality of heat pipes. The heat transfer process occurs at much closer approach temperatures therefore allowing the evaporation rate to occur at lower grade temperatures commencing at circa 800 ° C instead of the industry standard of 1600° C.

The design of the invention comprises a plurality of heat pipes in a specific configuration to evaporate water to steam at a directly controlled flow and pressure rating. The invention improves the flow design 'rate' of the current art by definition of the physics of 'from and at'. The energy meter provides an instantaneous reading of energy consumption within the building which is displayed on the display of the controller. By incorporating a communication device such as a modem, the controller permits off-site monitoring of energy consumption for maintenance and billing purposes. The plurality of magnetic ionization modules includes a fuel magnetic ionization module and a water magnetic ionization module. Each magnetic ionization module incorporates ceramic magnets for charging the molecules in hydrocarbon fuel or minerals in water. In use, the magnetic ionization modules circumscribe a plurality of fuel inlet pipes and/or water inlet pipes from which a strong magnetic field is applied to the material flowing within these pipes. The magnetic field serves to charge the fuel molecules to effect a more complete and efficient combustion and to charge the mineral molecules in water to prevent crystallization.

BRIEF DESCRIPTION OF THE DRAWINGS

The teachings of the present invention can be readily understood by considering the following detailed description in conjunction with the accompanying drawings, in which: FIG. 1 illustrates diagrammatically the present invention adapted for the generation and delivery of steam to an end user i.e. laundry; FIG. 2 illustrates a block diagram of the controller of the present invention;

FIG. 3a illustrates a cross-sectional elevation view of the boiler of the present invention depicting the configuration of the steam generation process within the said boiler;

FIG. 3b illustrates a cross-sectional top view of the boiler of the present invention along line 3b-3b of FIG. 3a;

FIG. 4 illustrates a perspective view of the heat pipe of the present invention; FIG. 5 illustrates a perspective view of the magnetic ionization module of the present invention;

FIG. 6 illustrates a configuration of the magnetic ionization modules around a pipe;

FIG. 7 illustrates a second configuration of the magnetic ionization modules around a pipe;

FIG. 8a illustrates a prior art dryback boiler;

FIG. 8b illustrates a prior art wetback boiler;

FIG. 9a illustrates a prior art Lancashire boiler (elevation view);

FIG. 9b illustrates a longitudinal cross-sectional view along lines 9b- 9b of the boiler of FIG. 9a;

FIG. 10 illustrates a prior art two-pass, dryback economic boiler;

FIG. 11 illustrates a prior art three-pass, wetback economic boiler;

FIG. 12 illustrates a prior art package boiler;

FIG. 13 illustrates a graph of water temperature vs. oxygen content; and

FIG. 14 illustrates a "From and At" graph for performance of the present invention.

To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures.

DETAILED DESCRIPTION

Figure 1 depicts the apparatus of the present invention as a system adapted for the generation of steam for industrial/commercial operations such as laundries and other similar applications. Such buildings and their processes contain plant and equipment that require steam for various applications such as heating water, drying, and the like. The present invention incorporates a controller and a steam generation boiler with a plurality of heat transfer sections specifically operating to maximize thermal transfer in direct proportion to steam demand (load). A further plurality of magnetic ionization units improve the combustion of hydrocarbon fuels within the boiler structure. For the purpose of describing the application in a practical application, a laundry process has been selected. This enables a consistency in descriptive application. However, the performance of the present invention can be replicated to any steam product application.

Figure 1 depicts the integration of a system 100 of the present invention with the typical steam requirements and operating components of commercial laundry. The system 100 comprises a steam boiler 104, a controller 110 a plurality of ionization modules 160.

A gas inlet pipe 101 provides natural gas to fuel the boiler 104. A gas meter 102 and a fuel magnetic ionization module 160 are dispersed along the gas inlet pipe 101 for monitoring the consumption of the fuel and for altering the change of the fuel molecules respectively. In turn the boiler 104 provides steam to a distribution manifold 120 via a flow pipe 106. Sub cooled waste gases from the combustion process within the boiler 104 are expelled through flue 131. Furthermore a secured water ionization module 170 is dispersed along a boiler feed pipe 150 preventing crystallization of minerals on the heat transfer pipes (heat pipes) (not shown) within the boiler 104. The distribution manifold 120 serves as a central exchange point for any number of supply circuits into a said process. Two such circuits are circuit 111 to washing machines 114 and circuits 112 to drying machine 115. Those skilled in such applications will know any number of circuits can be arranged from such a manifold. In circuit 111 to the washing machines 114 the steam is directly mixed with water supplied from a water tank 113. In an application of this type there is what is known as total loss, no condensate return. In circuit 112 to the drying machines 115 the steam gives up its latent heat to the drying process and condenses inside a heat transfer coil (not shown) within the dryer. The condensate returns via a pipe 116 to the boiler feed tank 117. The boiler feed tank 117 will automatically provide a balanced mass of feed water to the boiler 104 via the boiler feed pipe 150 and a feed pump 108. The fresh water make-up into the feed tank 117 is provided via pipe work from mains water 146, at a temperature of the condensate return (on the order of 140°F to 180°F). Good boiler house practice would lift the temperature of the feed tank to a temperature of circa 185°F via direct steam injector 148. This temperature is limited to 185 °F to prevent cavitations at the feed pump 108.

A piped circuit 121 from the feed tank 117 pumps mains cold water make-up via a circulating pump 122 through a dedicated heat transfer section in the boiler 104. The pipe work delivers pre-heated water into the feed tank via the same circuit 121. A second piped circuit 123 from the feed tank pumps the combined feed tank water via pump 124 into a dedicated heat transfer section within boiler 104. Both of these piped circuits provide heat from what would have been waste flue gases. The result is a temperature rise in combined feed tank water. This process will eliminate the constant need for steam injection into the feed tank 117.

A controller 110 monitors the "loading" within the building or processes and responds by matching the demand with the most cost effective heat generating source. Loading is defined as the sum total of the various demands for steam within a building. The controller 110 calculates loading by gathering information from a plurality of temperature and mass flow sensors 182, 183, 184 and 185 a plurality of thermostats. The controller 110 is programmed to calculate the instantaneous energy need of the steam. The controller 110 takes into account the circuits (supply circuits and demand circuits), the flow of the settings of the thermostats, historical energy consumption patterns, programmed settings and ad hoc commands for determining and predicting the most cost effective method of meeting the energy demands of the building/process. This load matching feature enhances the thermal efficiency of the present invention. Furthermore, although FIG. 1 depicts four (4) supply circuits and two (2) demand circuits, those skilled in the art will realize that a multitude of supply and demand circuits can be employed within a building.

Optionally, a modem 125 and an energy meter 126 are coupled to the controller for providing off-site monitoring capabilities. A remote station 127 in communication with the controller 110 will be able to monitor the steam energy demands of the building and the performance of the various heat generating components within the building. This configuration permits off- site detection of failures and enhances billing functions.

FIG. 2 depicts a block diagram of the controller 110 of the present invention. The controller 110 comprises a processor 200, a display 210, a data input device such as a keypad or keyboard 220, data storage section 230, and an optional analog-to-digital converter 260. The controller is coupled to a plurality of sensors 182 ... 186, 133 and 140 (not all sensors are shown in FIG. 2).

The processor 200 is a general purpose programmable microprocessor commercially available from companies such as Intel Corporation. The processor 200 becomes a special purpose machine when running a computer program for executing steps of generating steam within the system 100. For example, the processor 200 is programmed to receive information from a plurality of commercially available temperature and mass flow sensors 182, 183, 184, 185, and flow sensor 182. The temperature sensors disposed along the various circuits, report the load condition to the processor 200. This data in combination with the historical trends, permits the processor 200 to calculate the current loading within the building. The plurality of sensors are coupled to an optional analog-to-digital converter 260 via a plurality of signal connections 270. The analog-to-digital converter 260 converts analog data signals into a digital form, thereby permitting the processor 200 to communicate with analog sensors.

The data received from the sensors are stored in data storage section 230. Data storage section 230 may incorporate a number of devices such as a disk drive, semiconductor memory or other storage media. The cumulative gathering of data forms a historical energy consumption database from which the processor is able to learn the energy consumption pattern of the building. Thus, processor 200 is able to determine the instantaneous energy loading as well as anticipate upcoming energy needs and execute steps necessary to meet those needs by actuating valves for regulating water or steam flow, increasing or decreasing boiler temperature and the like.

A plurality of commercially available control sensors 133, 134, 135, 136, 137, 138 and 140 are coupled to the processor 200 via a plurality of signal connections 280. The control sensors are coupled to the various components on the boiler that effect the firing characteristic of the boiler together with the amount and or variation of combustion air mix. Further various controls such as pumps and solenoid valves are also controlled by the processor. Thus, when the processor detects and assimilates a demand level for steam and its relevant total enthalpy, it calculates the demand and responds by infinitely controlling the firing characteristic utilizing various heat transfer sections in the boiler (explained in greater detail below). This intelligent process responds by activating the exact heat generating source to match the demand. In the preferred embodiment of the present invention the boiler will only be fired in exact accordance of demand. An optional energy meter 126 is electrically coupled to the processor

200 for reporting the energy consumption of the building. For example, such energy meter is coupled to the gas meter 102 or other meters (electric and oil) for monitoring the instantaneous consumption of energy within the building. Processor 200 incorporates this data for independent client billing and historical analysis of energy consumption pattern.

Furthermore, the display 210 and data input device 220 are electrically coupled to the processor 200 for displaying the status of the system and for entering specific instructions respectively. System information such as energy consumption rate, pressure settings and the like can be reported continuously to an operator via the display 210. The operator may query the system via the data input device 220 for additional information or send operating instructions to the processor 200. For example, an operator may decide to override the load matching process of the processor 200 by requesting the activation of the boiler. In such situation, the operator may be willing to sacrifice efficiency in order to respond to an immediate energy need.

A modem 125 is coupled to the processor 200 for providing off-site monitoring and reporting capabilities to a remote station 127. Thus, a remote station may monitor a number of different off-site installations simultaneously. Since the controller 110 maintains a comprehensive up-to- date report on the energy consumption of a building, remote station 127 is able to detect failures and also perform billing functions.

FIGs. 3a and 3b illustrate the steam boiler 104 of the present invention which incorporates a plurality of heat transfer sections 325, 326, 327, 328, 329, 330 and 331. All of the heat transfer sections utilize the principals of heat transfer of the heat pipe 300 discussed below. The main boiler housing 124 is constructed from a corrosion resistant material such as steel. The structure will be of welded construction to a coded standard that qualifies steam pressure operation. The upper section of the boiler will comprise a flanged dished end 322 to withstand pressures of up to 300 psi, and have a hinge 323, to facilitate inspection.

The combustion of the hydrocarbon fuel and the mixing of the combustion air takes place in chamber 320. A gas burner 119 and the primary air circulation fan 118 (shown in FIG. 1 also) are infinitely controlled up or down via controller 110. The air flow circuit throughout the boiler encompassing all areas of heat transfer induces ambient air at the inlet 332. This air is immediately pre-heated from the air to air heat pipes in section 331. The pre-heated air travels downward to mix in chamber 320 with the burner flame from burner 119. The high temperature furnace gases circa 800°C, travel into the furnace tube 332. The furnace tube is welded from a corrosion resistant material generally steel and although perforated with a multiplicity of holes 333 to allow the controlled penetration of furnace gases throughout the heat transfer sections, will act as a structural support to the water tube plate 334 which although constructed from a thicker gauge of steel plate, will be under pressure by definition of generation of steam through heat transfer sections 325, 326, 327 and 328.

Steam is generated in the steam chamber 335. The water content from evaporation is kept at a desired level by water level sensors 336 and 337, high level and low level respectively. Projecting into the water from a primary heat transfer section 325 are heat pipes 300. The tube plate 334 form a water tight and gas tight seal between the furnace and water sections. The heat pipe 300 protrudes both sections and transfers energy through the concentric plurality of pipes. The gas temperature in the furnace commences at circa 800°C depending on load demand. The plurality of heat pipe surface area guarantees the generation of small steam bubbles beneficial in the production of 'drier' steam in the steam chamber 335. Lesser surface area encourages larger steam bubbles giving a 'wetter' steam production after requiring separation or major superheating. The furnace gas sub-cooling at this stage leaves the primary furnace tube 332 and enters into a secondary steam production section 326. Due to the air flow configuration and the negative pressure, the volute configuration ensures a consistent velocity around the second stage plurality of heat pipes 300 in section 326. The free volume in these sections is suitably selected that minimal pressure chop occurs as the gases pass around the heat pipes 300. All of the heat pipes shown are disposed with one end in the high temperature gas the other end in the water section, facilitating the continuous evaporation/condensing mode, thus transferring heat at a much greater rate then through solid metal.

Upon the high temperature gas completing heat transfer stages 325 and 326, the gas enters the exhaust flue outlet 338. These exhaust flue gases will follow an internal peripheral duct within the upper section 340 of the boiler 104. Five more stages of heat transfer will occur before the flue gas finally exits to atmosphere. As the temperature gradually diminishes each remaining stage, 327, 328, 329, 330, 331 will transfer useful energy into the boiler process lifting thermal efficiencies into the 90% range . The steam chamber 335 which contains the steam evaporation flow and pressure as dictated by the controller 110, will have the assistance of maintaining pressure from a third heat transfer section 327 acting as a superheater from the early stage of flue gas energy transfer. The heat pipes 300 in this section are essentially gas to gas in transfer configuration. Due to the heat pipe's ability to transfer heat at close approach temperature, the temperature of the flue gas at this point will be higher than the temperature of the steam in chamber 335, thus transferring energy into the steam and lifting pressure. The term superheater is not being used in quite the same context as a high pressure superheater in say a power station steam generation plant. However the same heat transfer physics apply thermodynamically the primary benefit being the negating of burner over use in satisfying a 'dry cycling effect' once pressure levels in the boiler begin to fall. The controller is matching mass flow and pressure demands accordingly. To facilitate heat transfer, i.e. when the boiler fires up after any given shut down period there will be for a short period of time no steam in the steam chamber 335. At this stage the condensing section of the heat pipe 300 will have nowhere to 'sink' its recovered heat. To facilitate safety, a solenoid valve (not shown) will open of feed pump 108 and sprays water over the said heat pipes 300 through a nozzle 310. As the flue gas is subcooling, it passes to a fourth heat transfer section 328. In this section a matching peripheral water manifold 324 facilitates one end of the heat pipe 300 in the exiting flue gas. The other end in pressurized water jacket being fed by the boiler feed pump 108. This will lift the water temperature under pressure and allow quicker evaporation in the water/steam chamber. A fifth heat transfer section 329 is a repeat of section 328 except the water flow is not under pressure from the boiler feed pump. In this section, an independently pumped 124 circuit from the boiler feed tank, picks up heat from the plurality of heat pipes 300 in this section, and returns to the feed tank eliminating the need for the steam injector 148 to pre heat the feed tank 117.

A repeat configuration to 329 is included in a sixth heat transfer section 330. In this instance the make up water for the boiler feed tank is pumped via pump 122 independently through the section 330 and returned to the feed tank. The flue gases have now sufficient heat available only for air pre heating . To accommodate the combustion air pre heat, the flue gas is directed in a downward fashion and rises to the inlet of the exhaust fan 118 passing on its rise over section 331. In a contraflow fashion the downward travelling fresh air intake 332 will transfer heat through heat pipes 300 installed in a horizontal fashion. The pre heated fresh air will then blend with the gas burner in section 120 and the process of maximizing heat transfer through the steam generation is complete.

In summation, The design criteria encompasses maximum heat transfer at seven sections 325, 326, 327, 328, 329, 330 and 331 within the system:.

325: The primary furnace chamber is where the burner flame merges with the combustion air, both of which are infinitely controlled in direct proportion to total load or demand. The heatpipes located in this primary furnace tube transfer heat and evaporate water into steam, pressurizing the steam chamber. The furnace tube (steel) is perforated with a series of holes to allow the hot gases to permeate to the second stage of steam evaporation.

326: The volute configuration of this section guarantees uniform velocity due to the density reduction of the sub cooling gases. The largest mass of heat pipes are housed in this section, which in turn evaporate water to steam. 327: The sub cooling gas then pass from primary steam production into the section known as the exhaust flue. In this first stage of the exhaust flue there is sufficient high grade heat to further transfer energy into the steam chamber via a further plurality of heat pipes. This will benefit the steam chamber with a degree of 'super heating' to facilitate higher steam pressure controls. It will also maintain steam pressure levels even when the burner is not firing at maximum capacity.

328: The further sub cooling gases will have energy transferred via a further plurality of heat pipes, this time pre heating boiler feed water and delivering this water at pressure into the boiler. This is a major benefit in the boiler rating as 'from and at' as the enthalpy in the boiler feed water is substantially enhanced due to its higher temperature levels i.e. from circa 70 ° C to 120 °C plus.

329: As in section 328, the sub cooling gases further transfer heat only this section accommodates the water contained in the boiler feed tank sometimes known as the hot well. The combined hot well water will be circulated permanently through this section lifting the hot well temperature to an operating level of circa 85 °C.

330: Many steam application processes 'lose' the steam into the actual process. This water is replaced in what as known as water make-up. This water is normally delivered from mains and is at a temperature of 10 °C. This section will pass mains water through a plurality of heat pipes prior to filling the hot well.

331: Finally, as the sub cooling gases continue there is little energy left to effectively transfer energy into the feed water. However, the final section of heat transfer contains a plurality of heat pipes which will transfer the energy remaining into the combustion air requirements. This preheated combustion air improves combustion in the furnace by bringing up the initial temperature of the air to fuel mix prior to flame ignition. Pre heating air raises overall thermal efficiency and reduces in size the furnace tube section. The heat pipes in this section are configured in a fashion to transfer energy from the exhaust flue gases to the incoming mass of fresh air.

FIG. 4 illustrates a perspective view of the heat pipe 300 of the present invention. The heat pipes 300 are incorporated into each of the heat recovery module for recovering heat from waste gases or liquids. In the preferred embodiment of the present invention, the heat pipe 300 is a sealed hollow copper pipe 500 having a evaporation section 520 and a condensation section 530. The heat pipe includes a hollow, cylindrical wick 510 having an outer surface 512 which rests against an inside diameter 502 of the copper pipe 500 and an inner surface 514 which circumscribes a vapor space extending longitudinally through the interior of the copper pipe. Furthermore, the heat pipe is evacuated and filled with a small quantity of an evaporable working fluid, such as water or alcohol. The working fluid is inserted into the heat pipe via a barrel with a threaded section (not shown) located on the condensation section of the heat pipe. In use, the evaporation section 520 of the heat pipe is exposed to a heat source from which heat is recovered and, contemporaneously, the opposite condensation section 530 of the pipe is cooled within a water manifold 540. The heat is transferred efficiently between a stream of hot gases/fluids and a stream of water within the water manifold.

The substantially cylindrical wick 510 is principally a tube of fine wire mesh constructed from a suitable metal such as bronze. Since the vapor pressure in the evaporation section 520 is greater than the condensation section 530, the evaporated working fluid moves from the evaporation section 520 toward the condensation section 530. The evaporated fluid is condensed in the cooler condensation section and is drawn back into the wick via capillary action along the wick surface that circumscribes the vapor space. The internal operation of the heat pipe allows it to be used successfully in a substantially horizontal position as shown in FIG. 4 and FIG. 5. In this manner, heat is recovered from waste gases and liquids through the repeated process of evaporating and condensing the working fluid.

Additionally, the sealed end of the evaporation section is manufactured by a high temperature silver soldering process to withstand high grade heat in the range of approximately 1,000° C. In contrast, the barrel on the sealed end of the condensation section is only soldered with a conventional plumber grade solder. In the event that the heat pipe is exposed to excessive heat, the "soft" solder will decay to allow the release of pressure from the heat pipe into the water manifold. This construction of the heat pipe prevents the continual build-up of vapor pressure within the heat pipe which may cause the heat pipe to explode. Additionally, the release of the vapor pressure into the water manifold permits the heat pipe to fail in a control manner, thereby minimizing the explosive effect.

FIG. 5 illustrates a perspective view of a magnetic ionization module 1100 of the present invention. The plurality of magnetic ionization modules employed in the subject invention are for example the fuel magnetic ionization module 160 and the water magnetic ionization module 170. The two magnetic ionization modules are identical in construction, but they are applied to different parts of a building to achieve different results. The fuel magnetic ionization module 160 serves to charge hydrocarbon fuels to effect a cleaner combustion process. On the other hand, the water magnetic ionization module 170 operates to charge mineral molecules in the water to prevent crystallization.

Water and most organic compounds are diamagnetic, as are many nonmetals. A diamagnetic substance possesses a negative magnetic susceptibility which is displayed by a repulsion of the compound from an applied magnetic field. This negative magnetic susceptibility is a consequence of an induced magnetization generated by lines of magnetic flux penetrating the electron loops around the atoms. Diamagnetic materials are made up of molecules that have no permanent magnetic dipole moment. When an external magnetic field is applied, magnetic dipoles are induced, but the induced magnetic dipole moment is in the direction opposite to that of the field. Namely, the direction of this induced magnetization is opposite to that of the external magnetic field. In effect, the external magnetic field increases the orbital speed of electrons revolving in one direction, and to decrease the speed of electrons revolving in the other direction. The net result is a net dipole moment opposing the external magnetic field. The external magnetic field reduces the stability of the electrons and increases the ion's affinity for other stable electrons. Thus, the resulting diamagnetic ions exhibit a net positive charge or "positive ionization".

The fuel magnetic ionization module 160 serves to charge the hydrocarbon fuel within the fuel inlet pipe. The process of positive ionization encourages fuel molecules to bond with negatively charged oxygen, thereby resulting in a more complete and efficient combustion. Similarly, the magnetic field within the water magnetic ionization module 170 serves to charge the mineral molecules in water to prevent crystallization. The positively charged mineral molecules have a tendency to dissolve into the charged water molecules.

Each magnetic ionization module 1100 comprises a plurality of ceramic magnets 1200, a hinge 1210, magnet housings 1220 and a plurality of securing devices such as screws 1230. In the preferred embodiment of the present invention, the ceramic magnet blocks 1200 are used to generate a magnetic field strength of approximately 2,000 gauss through the center of a pipe 1240 disposed therebetween, the pipe having a diameter between 12 to 15 millimeters. The dimension of the magnet is approximately 60 millimeters in length, 20 millimeters in height and 15 millimeters in width. Such ceramic magnets are available from Bakker Madava of Holland.

Each ceramic magnet 1200 is coupled to a magnet housing 1220 by a plurality of securing devices 1230. The magnet housing is constructed from a suitable material such as plastic and is coupled to a zinc plated hinge 1210 for joining a pair of magnets 1200. The magnets are oriented such that the north pole of one magnet is facing the south pole of another magnet, thereby causing attraction between the two magnets 1200. This hinging configuration permits a single magnetic ionization module to easily fit over a wide range of pipe sizes (up to 50 millimeters). In use, the magnetic ionization module circumscribes the pipe 1240 from which a strong magnetic field is applied to the material flowing within the pipe.

FIG. 6 and FIG. 7 depict two configurations of the magnetic ionization modules adapted to pipes of different sizes and shapes. If a pipe 1300 is particularly large, a plurality of magnetic ionization modules 1100 are employed to provide adequate magnetic field strength as shown in FIG. 6. Alternatively, the magnet housings 1220 can be modified to accommodate additional magnets 1200 as shown in FIG. 7 adapted to an elongated pipe 1400.

The use of the 'from and at' graph FIG. 14, can be shown in the following example which demonstrates calculating the actual output from a boiler. Example

A boiler has a 'from and at' rating of 2000 kg/h and operates at 15 bar g whilst the feed water temperature is 68°C.

Using the graph The percentage 'From and at' rating = 90%

Therefore output = 2000 kg/h x 90%

Boiler output = 1800 kg/h

The use of the following equation will determine a factor to produce the same result...

A = Specific enthalpy of evaporation at atmospheric pressure

B = Specific enthalpy of steam at operating pressure

C = Specific enthalpy of water at feedwater temperature

Therefore: Factor -

R- C

Using the above information in this equation will produce the following factor.

Factor

Factor = 0.899

Therefore boiler output = 2000 kg/h x 0.899 = 1799 kg/h

There has thus been shown and described a novel apparatus and method that incorporates a controller, a steam boiler with a plurality if heat transfer sections for improving the thermal efficiency of a steam generation system and a plurality of magnetic ionization modules for improving the combustion of hydrocarbon fuels. Many changes, modifications, variations and other uses and applications of the subject invention will, however, become apparent to those skilled in the art after considering this specification and the accompanying drawings which disclose the embodiments thereof. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention, which is to be limited only by the claims which follow.

Claims

What is claimed is:

1. Apparatus for generating steam comprising: a steam boiler; a plurality of ionization modules connected to said steam boiler; and a controller connected to said steam boiler.

2. The apparatus of claim 1 wherein the steam boiler has a plurality of heat transfer sections.

3. The apparatus of claim 2 wherein the plurality of heat transfer sections is seven.

4. The apparatus of claim 1 wherein at least one ionization module is connected to a fuel delivery line of said steam boiler.

5. The apparatus of claim 1 wherein in least one ionization module is connected to a water delivery line of said steam boiler.

6. The apparatus of claim 4 wherein the fuel delivery line ionization module ionizes fuel molecules within the fuel line to promote enhanced combustion.

7. The apparatus of claim 5 where the water delivery line ionization module ionizes minerals in the water to prevent crystallization of the minerals.

8. The apparatus of claim 1 wherein the controller is connected to a plurality of sensors that monitor system conditions.

9. The apparatus of claim 1 wherein the controller is further connected to a remote station.