CN101251045B - Biomass energy circulating power generation process and power generation system thereof - Google Patents

Abstract

A biomass energy cycle power generation process is characterized by comprising the following steps: (1) gasifying the biomass raw material, converting the biomass raw material into combustible gas, and then sending the combustible gas into a gas internal combustion engine set to generate power after dedusting, decoking and purifying; (2) feeding biomass raw materials or ash residues generated in the gasification power generation process in the step 1 or a mixture of the biomass raw materials and the ash residues into a steam boiler to be combusted to generate superheated steam; introducing the exhaust waste heat of the gas internal combustion engine set in the step 1 into a waste heat boiler to generate superheated steam; (3) and (3) sending the superheated steam generated by the steam boiler and the waste heat boiler in the step (2) into a steam turbine generator unit together for power generation. The invention fully utilizes the heat energy and products generated in each processing link in the biomass energy gasification power generation process, circularly generates power, greatly improves the power generation efficiency, fully utilizes the waste and reduces the operation cost. The invention also discloses a power generation system for realizing the biomass energy circulating power generation process.

Description

A biomass energy cycle power generation process and its power generation system

technical field

The invention relates to a power generation process and a power generation system thereof, in particular to a biomass energy cycle power generation process and a power generation system thereof.

Background technique

New energy technology is one of the most influential technologies in the world's economic development in the 21st century. Human beings will eventually rely on the development of new energy industries to solve the global energy crisis and environmental pollution problems and achieve sustainable development. Among the renewable energy encouraged by the state, the largest one is the power generation and utilization of biomass energy. my country has abundant biomass energy resources. According to estimates, my country's theoretical biomass energy resources are about 5 billion tons. At present, the available biomass energy resources are mainly biomass waste, including crop straw, chaff, firewood, industrial organic waste and municipal solid organic waste. Faced with the problems of high consumption, high pollution, and resource and environmental constraints that accompany economic development, in recent years, China has begun to seek a comprehensive transformation of the economic growth model and take the road of economical development. Circular economy is a kind of high-efficiency utilization and recycling of resources as the core, based on the principle of "reduction, reuse, and recycling", with low consumption, low emission, and high efficiency as the basic characteristics, in line with the concept of sustainable development The economic growth model is a fundamental change to the traditional growth model of "mass production, mass consumption, and mass waste". Biomass energy is an important energy source. It is estimated that by the next century, 40% of the world's energy consumption will come from biomass energy. my country has abundant biomass energy resources. 70% of my country's rural energy is biomass. The volume is more than 600 million tons. With the development of the economy, the improvement of people's living standards, the strengthening of environmental protection awareness, the reasonable and efficient development and utilization of biomass energy must be more and more valued by people.

At present, the application of biomass gasification power generation is one of the effective methods for clean utilization of biomass energy. It can convert biomass energy into electric energy without generating pollution, and achieve the purpose of obtaining high-grade energy from low-grade energy. In particular, the small-scale biomass gasification power generation process and power generation system are simple, flexible, and relatively easy to popularize and apply. However, the medium and large biomass gasification power generation process and power generation system generally have a power generation ≥ 2MW, and encounter many practical problems in the actual industrialization process, mainly in the following aspects:

(1) The utilization efficiency of the system is low, generally only about 15%. For this problem, attempts have been made to increase efficiency by adding waste heat boilers and steam turbines to generate electricity, but the system is unstable and the effect cannot be achieved;

(2) A large amount of ash, sludge, organic sewage, tar and other wastes are produced in the process of gasification and purification. These wastes contain high heat and are not used. Although some of them can be used as fertilizers and returned to the field, some Some of them are used as industrial raw materials, such as: insulation materials, steelmaking materials, etc., but most of the waste cannot be used, which seriously affects the normal operation of the power plant and also brings certain harm to the environment;

(3), the efficiency of the gas internal combustion engine power generation process is not high, generally about 30%, and most of the heat is lost from the tail gas and cooling water.

To sum up, there are still many problems in the current medium and large-scale biomass gasification power generation process and system. The operating cost of the power plant is too high and the efficiency is low. If the efficiency is not further improved, it will be difficult to commercialize and promote industrialization.

Contents of the invention

The purpose of the present invention is to provide a biomass energy cycle power generation process and its power generation system, which have high power generation efficiency, stable operation, efficient recycling of waste, and are environmentally friendly and pollution-free.

The technical solution of the present invention can be realized by the following technical measures, a biomass energy cycle power generation process is characterized in that it comprises the following steps:

(1) The biomass raw material is gasified, converted into combustible gas, and then sent to the gas internal combustion unit for power generation after dedusting, decoking and purification;

(2) Send the biomass raw material or the ash generated in the gasification power generation process described in step (1), or the mixture of the two, into the steam boiler to burn to generate superheated steam, that is, in the steam boiler, only the gas can be burned The ash generated in the process of chemical power generation can also burn the mixture of biomass raw materials and ash, which is mainly flexibly controlled according to the required power generation; the exhaust waste heat of the gas internal combustion unit described in step (1) is passed into the waste heat Superheated steam is produced in the boiler; the ash produced in the gasification power generation process includes the dry ash produced after the gasification of the biomass raw material described in step (1) and the wet ash produced after the purification of the combustible gas slag; in order to further utilize the waste heat generated in the power generation process, the high-temperature gas waste heat generated in the gasification power generation process in step (1) can be sent to the heat exchanger to generate a steam-water mixture, and then the steam-water mixture is sent to the waste heat boiler or steam boiler or sent to waste heat boiler and steam boiler respectively to further generate superheated steam;

(3) Send the steam boiler described in step (2) and the superheated steam produced by the waste heat boiler together into the turbogenerator unit to generate electricity.

The invention makes full use of the heat energy and products generated in various processing links in the biomass energy gasification power generation process, and circulates power generation, so that the power generation efficiency is greatly improved, wastes are fully utilized, and operating costs are reduced.

The present invention can also be improved as follows: the heat energy of the hot water generated by the gas internal combustion unit described in step (1) in the cycle cooling process is converted into electric energy, that is, the above-mentioned hot water can be converted into electric energy through the medium of the heat exchange equipment and the expansion power generation device. Heat exchange, so that the medium steam after heat exchange drives the expansion power generation device to generate electricity, such as driving the screw expansion generator set to generate electricity, and the water after heat exchange and cooling continues to be used to cool the gas internal combustion set, so that the cycle is continuous to achieve full use of heat. The purpose of water waste heat.

The present invention can also be further improved as follows: the steam turbine generator set described in step (3) also produces some hot water in the working process, such as: the hot water produced by the steam turbine in the circulation cooling process, the present invention uses these hot water heat energy It is also used to generate electricity: part or all of the hot water generated by the turbo-generator unit is directly used to cool the gas internal combustion unit, and then the hot water generated is further used to generate electricity. For example, the hot water can be exchanged through heat The equipment exchanges heat with the medium of the expansion power generation device, so that the medium steam after heat exchange drives the expansion power generation device to generate electricity, and the water cooled by heat exchange in the steam turbine circulation cooling system continues the next cycle cooling process.

The invention utilizes gas power generation and hot water power generation double-cycle power generation system to bring double economic benefits: on the one hand, it can reduce the cooling water volume of the circulating cooling system, thereby reducing system investment and water pump operation costs, and reducing self-consumption electricity; on the other hand, it can increase Waste heat power generation, improve system efficiency.

In the biomass energy cycle power generation process described in the present invention, it can be selected according to the required power generation whether to use the ash generated in the combustion gasification power generation process alone to send it to the steam boiler for power generation, or to burn the biomass raw material in the steam boiler at the same time and ash mixture to generate electricity. In the latter, the dry ash produced after the gasification of the biomass raw material described in step (2) and the wet ash produced after the purification of the combustible gas can be mixed first, and then sent to the steam boiler for combustion.

A biomass energy power generation system for realizing the above-mentioned biomass energy cycle power generation process, including a gasification power generation unit, and the gasification power generation unit includes a gasifier, a gas purification device, a gas internal combustion unit and a circulating cooling system connected in sequence The equipment is characterized in that the power generation system further includes a steam power generation unit, the steam power generation unit includes a steam boiler, a waste heat boiler and a steam turbine generator set, and the exhaust outlet of the gas internal combustion unit is connected to the waste heat boiler; The gas purification device is also connected with a sewage treatment tank, and the high-temperature ash discharge valve for discharging dry ash on the gasifier and the wet ash discharge port of the sewage treatment tank are jointly connected to the fuel inlet of the steam boiler; The waste heat boiler mentioned above is connected in parallel with the steam boiler and then connected with the steam turbine generator set. The turbogenerator set of the steam generating unit includes a steam turbine and a generator connected thereto, the steam turbine is connected with a steam turbine cooling water pump, and the cooling water pump is connected to the cold water pool of the circulating cooling equipment; the circulating cooling The equipment cools the exhaust temperature of the low-pressure cylinder of the steam turbine and reduces the exhaust pressure of the low-pressure cylinder, so that the steam can release energy to the maximum extent when it passes through the steam turbine and convert it into mechanical energy for the rotation of the steam turbine, which is used to drive the generator to generate electricity. The steam turbine is connected with a condenser, and the condenser is respectively connected to the waste heat boiler and the steam boiler through the condensate pump, the oxygen removal equipment, the feed water pump and the water supply pump, so that the waste heat of the steam discharged from the steam turbine can be fully utilized ; Among them, the feed water pump is first connected to the waste heat boiler through the heat exchanger. The inlet pipe of the circulating cooling water of the condenser is connected to the cold water pool through the steam turbine cooling water pump, and the return pipe of the circulating cooling water of the condenser is connected to the cooling inlet pipe of the gas internal combustion unit, that is, the cooling water pump will The cooling water is pressed into the condenser to exchange heat with the superheated steam that has done work, reducing the discharge pressure at the end of the steam turbine, and the circulating water that absorbs heat is sent to the cooling inlet pipe of the gas internal combustion unit through the return pipe, and then used to cool the gas internal combustion unit.

Based on the principle of biomass energy power generation, this power generation system further converts the exhaust heat of the gas internal combustion unit into electric energy, and reuses the dry and wet ash and other waste generated during the working process of the system, that is, combustion power generation, environmental protection Energy saving, lower operating costs, greatly improved power generation efficiency.

The gasification gas power generation of the gasification power generation unit of the present invention and the steam power generation of the steam power generation unit are combined into an organic whole, which can be unified or independent, not limited by each other, and can be used flexibly. For example, when the gas internal combustion unit is overhauled, the biomass raw material can be directly burned in the steam boiler to generate electricity; or, when the power generated by burning ash cannot meet the requirements, a certain amount of biomass can also be added to the steam boiler The fuel is used as a supplement to ensure the stability of the entire power generation system.

The present invention can be improved as follows, the biomass power generation system also includes a hot water power generation unit, which includes a hot water pool, a heat exchanger and an expansion power generation device connected in sequence, and the expansion power generation device is also connected in turn with a condenser and Working fluid pump, described working fluid pump links to each other with the heat exchanger that is used to connect hot water pool again, and this heat exchanger and condenser are also connected to the cold water pool of circulating cooling equipment; The return pipe of described circulating cooling equipment is connected with A hot tub is attached. The above-mentioned hot water power generation unit converts the hot water heat energy generated by the gas internal combustion unit during the cycle cooling process into electric energy, fully utilizes the waste heat of the hot water, thereby effectively saving energy and improving power generation efficiency.

The biomass power generation system of the present invention can also include a dry-wet ash mixer, and the high-temperature ash discharge valve of the gasifier and the wet ash discharge port of the sewage treatment tank are all connected with the dry-wet ash mixer. The inlet is connected, and the outlet of the dry-wet ash mixer is connected to the steam boiler. In this power generation system, the dry and wet ash are mixed and then burned to remove tar and other pollutants in the wet ash, which can not only eliminate the pollution of the wet ash, that is, sludge to the environment, but also make full use of the heat of the sludge.

Compared with prior art, the advantage of the present invention is:

(1). The biomass energy cycle power generation process and its power generation system described in the present invention, on the basis of the traditional biomass energy power generation technology, comprehensively innovates, adopts intensive comprehensive development and utilization of biomass energy, and increases the waste heat boiler , steam boilers and turbogenerator sets, combining gasification power generation with steam power generation, in the process of converting biomass energy into electric energy, resources are efficiently and recycled, energy-saving and environmentally friendly, and greatly reduce operating costs;

(2). The present invention also increases the links of direct combustion of biomass raw materials for power generation and hot water power generation, making full use of the heat energy and waste products generated during the power generation process of the main system of biomass power generation, and greatly improving the efficiency of power generation;

(3). In the power generation system of the present invention, the two parts of gasification gas power generation and steam power generation are combined into an organic whole, which can be unified or independent, without mutual restriction, and can be used flexibly, such as: when part of the gas internal combustion engine During group maintenance, biomass raw materials and ash can be mixed directly into the steam boiler and then burned to generate electricity, or only biomass raw materials or ash can be burned in the steam boiler according to site conditions, so as to ensure the stability of the entire power generation system. ; The power generation system is safe and reliable in operation, can be widely used in medium and large biomass gasification power plants, and has extremely high commercial promotion value.

Description of drawings

Fig. 1 is the flow block diagram of the combination process of biomass energy power generation process in embodiment 1 of the present invention;

Fig. 2 is a schematic diagram of a biomass power generation system according to Embodiment 1 of the present invention;

3 is a schematic diagram of a gasification power generation unit of a biomass power generation system according to Embodiment 1 of the present invention;

Fig. 4 is the flow block diagram of the combination process of biomass energy power generation process in embodiment 2 of the present invention;

5 is a schematic diagram of a biomass power generation system according to Embodiment 2 of the present invention;

6 is a schematic diagram of a gasification power generation unit of a biomass power generation system according to Embodiment 2 of the present invention;

Fig. 7 is a schematic diagram of the steam cycle thermal system of the steam power generation unit of the biomass power generation system in Example 2 of the present invention.

Detailed ways

The scope of protection of the present invention is not limited to the following specific implementation methods, and non-essential improvements made by others all fall within the scope of protection of the present invention.

Example 1

Embodiment 1 of the present invention is shown in Figures 1 to 3. The present invention can be popularized and applied by cooperating with large-scale rice factories to set up power plants or setting up biomass power plants in grain production bases. The power plant can be selected according to local biomass resources. The scale generally has two specifications of 5MW and 10MW.

The biomass power generation process of the present embodiment comprises the following steps:

(1) Treat biomass raw materials, such as crushing plant straw raw materials, and chaff raw materials can be used directly, and then gasify biomass raw materials, that is, convert solid biomass into combustible gases. The main source of these combustible gases The components are CO, H ₂ , CH ₄ , CO _{2 ,} etc., and the gasified gas also contains certain impurities, such as ash, coke, a small amount of tar, etc.; after dedusting, decoking and purification, it is sent to the gas internal combustion unit for power generation;

(2) Send the dry ash produced after the gasification of the biomass raw material in the gasification power generation process of step 1 and the wet ash produced after the combustible gas purification into the steam boiler 21 to generate superheated steam; The exhaust waste heat of the gas internal combustion unit 13 is passed into the waste heat boiler 9 to generate superheated steam;

(3) Merge the superheated steam generated by the steam boiler 21 and the waste heat boiler 9 in step 2 into the main steam main pipe, and finally send it into the turbo-generator set to drive the turbo-generator set to generate electricity.

The power generation system for realizing the above-mentioned biomass energy power generation process includes a gasification power generation unit 1 and a steam power generation unit 2. The gasification power generation unit 1 includes a gasifier 11, a gas purification device 12, a gas internal combustion unit 13, and a circulating cooling water pump connected in sequence. and cold water pool 7; gas internal combustion unit 13 is connected to one end of internal combustion engine cooling water pump 5, and the other end of internal combustion engine cooling water pump 5 is connected to cold water pool 7; steam generating unit 2 includes steam boiler 21, waste heat boiler 9 and steam turbine generator set, steam The turbo-generator unit comprises a steam turbine 22 and a generator 23 connected thereto. The steam turbine 22 is connected to one end of the steam turbine cooling water pump 6, and the other end of the cooling water pump is connected to the cold water pool 7; the steam turbine 22 is also connected to a condenser 25, which The boiler 25 is connected to the waste heat boiler 9 and the steam boiler 21 respectively through the condensate pump 26 , deaeration equipment 27 , feed water pump 28 and feed water pump 30 , and the steam waste heat discharged from the steam turbine 22 is fully utilized. Wherein, the feed water pump 28 is first connected to the waste heat boiler 9 through the heat exchanger 29 . The inlet pipe of the circulating cooling water of the condenser 25 is connected with the cold water pool 7 through the steam turbine cooling water pump 6 . The return water pipe of the circulating cooling water of the condenser 25 is also connected to the cooling water inlet pipe of the gas internal combustion unit 13, which greatly saves the water consumption of the cold water pool 7.

The gas purification device 12 includes a first-stage Venturi tower 121, a second-stage Venturi tower 122, a third-stage spray tower 123, a fourth-stage spray tower 124, a sewage separator 125, a Roots fan 126, and an electrostatic precipitator 127 connected in sequence. , the electrostatic precipitator 127 is connected to the gas internal combustion unit 13 through the gas storage tank 8; the gas purification device 12 is also connected with a sewage treatment pool 14, and the sewage treatment pool 14 includes a spray tower sewage circulation pool 141, a grease trap 142, Large sewage circulation tank 143, anaerobic tank 144, aerobic tank 145, inclined settling tank 146 and decolorization tank 147, the decolorization tank 147 is connected to the sewage inlet pipes of the third and fourth spray towers 123 and 124 respectively, and the first-level civil The sewage drainage pipes of the Venturi tower 121 and the second-level Venturi tower 122 are connected to the grease trap 142, and the sewage drainage pipes of the third-level spray tower 123 and the fourth-level spray tower 124 are connected to the water inlet of the spray tower sewage circulation pool 141 , through the physical precipitation of the sewage from the third and fourth stage spray towers 123 and 124, the large particles of sediment in the sewage are removed, and the water after precipitation is used by the Venturi tower again, that is, the water outlet of the sewage circulation pool 141 of the spray tower is directly Connect to the water inlet pipe of the first-level Venturi tower 121 and the second-level Venturi tower 122. The gasification furnace 11 includes a raw material bin 111 and a gasification furnace body 112. A separator 17 and a heat exchanger 18 are also provided between the gasification furnace 11 and the gas purification device 12. The heat exchanger 18 is mainly used to absorb high-temperature gas Sensible heat, the air inlet and air outlet of the blower are provided under the heat exchanger 18, and the air outlet is connected to the gasifier 11 through the blower to improve the thermal efficiency of the gasification reaction. The two ash discharge ports of the gasifier 11 and one ash discharge port of the separator 17 are connected to the steam boiler 21 through the high-temperature ash discharge valves 111a, 112a, and 17a below which are used to discharge dry ash. The fuel inlet of the sewage treatment pond 14 on the inclined sedimentation tank 146 is also connected to the fuel inlet of the steam boiler 21 through the sludge thickening tank 15 and the belt filter press 16. The exhaust outlet of the gas internal combustion unit 13 is connected to the waste heat boiler 9, and the waste heat boiler 9 is connected in parallel with the steam boiler 21 and then connected to the steam turbine 22 of the turbogenerator set.

In this embodiment, biomass raw materials include crop straw raw materials and rice husk raw materials. The power generation system is connected to the raw material processing system 3: the straw raw materials are transported from the straw storage yard 31 through the straw pulverizer 32 and the conveyor 33 to the operation silo 19, while the chaff is directly transported from the chaff silo 34 to the operating silo 19, and the raw material enters the gasification furnace body 112 from the operating silo 19 for gasification and combustion reaction, while the dry ash and combustible slag left by the gasification combustion The wet ash generated after gas purification is sent to the steam boiler 21 for direct combustion to generate electricity, and the waste heat of the exhaust gas from the gas internal combustion unit 13 passes through the waste heat boiler 9 to generate superheated steam.

Example 2

Embodiment 2 of the present invention is shown in Figures 4 to 7. The difference from the previous embodiment is that in the process of biomass power generation, in step 2, the waste heat of the high-temperature gas at the outlet of the gasifier 11 is first Send it into the heat exchanger 18 to generate a steam-water mixture, and then send the steam-water mixture into the waste heat boiler 9 or the steam boiler 21, or send it to the waste heat boiler 9 and the steam boiler 21 for combustion, further generate superheated steam, and then transfer to step 3 Promote the steam turbine generator set to generate electricity;

In step 2, the dry ash produced after the gasification of the biomass raw material and the wet ash produced after the purification of the combustible gas are first mixed, and then sent to the steam boiler 21 for combustion;

In step 2, when necessary, the biomass raw material and ash are directly mixed in the steam boiler 21 and then burned to generate superheated steam;

Convert the hot water thermal energy generated by the gas internal combustion unit 13 in the cycle cooling process in step 1 into electric energy: the hot water passes through the hot water pool 43 and then passes through the heat exchanger 42 to exchange heat with the medium of the expansion power generation device, so that the heat exchanged The medium steam pushes the screw expansion generator set to generate electric energy, and the water after heat exchange and cooling returns to the cold water pool 7, and continues to be used to cool the gas internal combustion set 13, so that the cycle continues.

The steam turbine 22 of the turbo-generator set in step 3 produces hot water during the circulation cooling process, and the heat energy of the hot water is also used for power generation: a part or all of the above-mentioned hot water is directly used to cool the gas internal combustion unit 13, and then the generated heat is The water is further used to generate electricity. The hot water passes through the hot water pool 43 and exchanges heat with the medium of the expansion power generation device through the heat exchanger 42, so that the medium steam after the heat exchange drives the screw expansion power generation unit to generate electricity, and the steam turbine circulation cooling system The water cooled by the heat exchange returns to the cold water pool 7 again, and so continues to circulate.

In addition, the low-pressure steam generated by the blowdown of the steam boiler 21 and the low-pressure steam generated by the leakage of the steam seal and the shaft seal can be directly connected to the hot water pool 43 for further power generation or heating.

The power generation system for realizing the biomass power generation process of this embodiment is different from the previous embodiment in that a water inlet and a water outlet are provided under the heat exchanger 18, the water inlet is connected to the feed water pump 28, and the water outlet is connected to the water supply pump 28. The water pump 30 is respectively connected to the waste heat boiler 9 and the water supply port of the steam boiler 21 to further generate superheated steam to drive the turbogenerator to generate electricity. The water supply pump 30 is connected to the waste heat boiler 9 through the heat exchanger 29 first.

The power generation system also includes a dry-wet ash mixer 10, and the high-temperature ash discharge valves 111a, 112a, and 17a below the raw material bin 111, the gasifier body 112 and the separator 17 are all connected to the inlet of the dry-wet ash mixer 10, and the sewage treatment The wet ash discharge port of the pool 14 is also connected to the inlet of the wet and dry ash mixer 10 through the sludge thickening tank 15 and the belt filter press 16, and the outlet of the wet and dry ash mixer 10 is connected to the steam boiler 21 again.

The gasification power generation system also includes a hot water power generation unit 4, which includes a hot water pool 43 connected in sequence, a circulating hot water pump 48, a filter 49, a heat exchanger 42 and an expansion power generation device. The expansion power generation device is a screw expansion power generation unit, including a screw Expansion power machine 44 and generator 45, and screw expansion power machine 44 is also connected with condenser 47 and working medium pump 46 successively, and working medium pump 46 links to each other with heat exchanger 42 again, and heat exchanger 42 and condenser 47 are also connected to respectively The cold water pool 7; the return pipe after the circulation cooling of the gas internal combustion unit 13 is connected to the hot water pool 43, and the above-mentioned hot water power generation unit 4 converts the hot water heat energy generated by the gas internal combustion unit 13 during the circulation cooling process into electric energy.

The steam boiler 21 and the waste heat boiler 9 are connected to the steam turbine 22 through the main steam main pipe, and the superheated steam is used to drive the steam turbine generator set to generate electricity. The steam turbine 22 is also connected to the cold water pool 7 through the steam turbine cooling water pump 6; the condenser 25 of the steam turbine 22 is sequentially It is connected to the water inlet of the heat exchanger 18 via a condensate pump 26 , deaeration equipment 27 and a feed water pump 28 . The water inlet pipe of the circulating cooling water of the condenser 25 is connected to the cold water pool 7 through the steam turbine cooling water pump 6, and the return water pipe of the circulating cooling water of the condenser 25 is connected to the cooling water inlet pipe of the gas internal combustion unit 13, which greatly saves the cooling water pool 7 of water consumption.

The hot water power generation unit 4 uses hot water and low-boiling medium for heat exchange, and drives the screw expansion power machine 44 to generate electricity after the medium evaporates. The screw expansion power machine 44 is suitable for steam, steam-water mixture, hot water, and polluted heat sources. medium. The hot water circulation process of the hot water power generation unit 4 is as follows: the hot water in the hot water pool 43 enters the heat exchanger 42, exchanges heat with the medium, turns into cold water, returns to the cold water pool 7, and cools the condenser 25 of the turbogenerator set , the condenser 47 of the screw expansion power machine 44, and then the return water pipe after cooling through the condenser 25 circulation is connected to the cooling water inlet pipe of the gas internal combustion unit 13, the gas internal combustion unit 13 is cooled, and the hot water produced returns to the hot water pool 43 , continue to the next cycle.

The medium circulation process of the hot water power generation unit is as follows: the medium enters the heat exchanger 42 through the working medium pump 46, and after heat exchange with the hot water, it becomes steam to drive the screw expansion generator set to generate electricity, and then condenses through the condenser 47, and continues to one cycle. The above-mentioned medium is a liquid with a low boiling point, generally lower than the boiling point of water, and may be a medium such as ammonia water.

The steam boiler 21 can also be connected to the continuous sewage expansion vessel 221 and the regular sewage expansion vessel 222 respectively through the continuous sewage discharge main pipe and the regular sewage discharge main pipe. The continuous sewage discharge expansion vessel 221 is also connected to the low pressure steam main pipe, and the low pressure steam main pipe is then connected to The hot water pool 43 makes full use of the heat of the low-temperature and low-pressure steam produced by the steam turbine in the working process. The steam turbine 22 can also be connected with a boiler water supply system 20, which is applicable to the situation of water shortage of the steam generating unit 2. The boiler water supply system 20 includes an industrial water tank 201 and an industrial water pump 202. The industrial water tank 201 is connected to the chemical water treatment system through the industrial water pump 202. The water is chemically treated, the treated soft water is connected to the desalinated main pipe, the steam seal heater 253 connected to the condensate pump 26 is connected to the condensate drain main pipe, and the condensate drain main pipe is connected to the drain tank 223 through the drain pump. The above-mentioned desalinated water main pipe and condensed water hydrophobic main pipe are jointly connected to the deaeration equipment 27. The deaeration equipment 27 includes a deaeration device 271 and a deaeration water tank 272 connected thereto. The deaeration water tank 272 is connected to the heat exchange via a feed water pump 28 Device 18.

In the above-mentioned embodiments, the waste heat boiler and the steam boiler can also be combined in series and then connected to the turbogenerator to generate electricity, and the sequence of the two in series can be set arbitrarily. The hot water in the hot water pool can also be used for heating in winter, as sending hot water to the heating point heater, and then returning to the cold water pool. In addition, there are two ways to further use the waste heat of the tail gas after the combustion of the steam boiler and the tail gas exhausted by the waste heat boiler: (1) as a heat source for drying biomass raw materials and wet ash; (2) after being discharged through the water in the hot water pool. It is also possible to further refine the lime ash left after the steam boiler is burned into silicon dioxide or process fertilizer, such as straw ash can be used as potash fertilizer, and the final lime content of this power generation system is lower than 5%. The excess black ash produced after the gasification of biomass raw materials, that is, ash residue, can also be further utilized. The aforementioned biomass raw materials may also include firewood, industrial organic waste, and the like.

In the above-mentioned embodiments, when necessary, such as when some gas internal combustion units are overhauled, the steam boiler can be directly mixed with biomass raw materials and ash to generate electricity, so as to ensure the stability of the entire power generation system. In the same way, only ash or biomass raw materials can be burned in the steam boiler, which is flexibly controlled mainly according to the required power generation.

Claims (7)

1. a biomass energy circulation electrification technique as well as is characterized in that comprising the steps:

(1) biomass material is gasified, be converted to inflammable gas, after dedusting, decoking purify, send into generating in the gas internal combustion unit (13) then again;

(2) with the lime-ash that produces in biomass material or the described gasifying electricity generation process of step (1), or the mixture of the two is sent into, and burning produces superheated vapor in the steam boiler (21); The exhaust heat of step (1) described gas internal combustion unit (13) is fed generation superheated vapor in the exhaust heat boiler (9); The lime-ash that produces in the described gasifying electricity generation process comprises that dry ash slag and described inflammable gas that the biomass material gasification back described in the step (1) produces purify the wet lime-ash that the back produces; The high-temperature fuel gas waste heat that produces in the gasifying electricity generation process in the described step (1) is sent into generation steam water interface in the heat exchanger (18) earlier, and this steam water interface is delivered to respectively in exhaust heat boiler (9) and the steam boiler (21) again, further produces superheated vapor;

(3) superheated vapor that the described steam boiler of step (2) (21) and exhaust heat boiler (9) are produced is sent in the Turbo-generator Set together and is generated electricity.

2. a kind of biomass energy circulation electrification technique as well as according to claim 1, it is characterized in that the hot water heat energy that step (1) described gas internal combustion unit (13) produces in the circulation cooling procedure is converted to electric energy: the medium of above-mentioned hot water by heat-exchange apparatus and expansion power generation device carried out heat exchange, thereby allow the medium steam after the heat exchange promote the generating of expansion power generation device, and the water after the heat exchange cooling continue to be used for cooled gas internal combustion unit (13).

3. a kind of biomass energy circulation electrification technique as well as according to claim 2, part or all that it is characterized in that hot water that Turbo-generator Set is produced in the course of the work directly is used for cooled gas internal combustion unit (13), then the hot water that the comes out medium by heat-exchange apparatus and expansion power generation device is carried out heat exchange, thereby allow the medium steam after the heat exchange promote the generating of expansion power generation device, the water after the heat exchange cooling then continues next circulation cooling procedure.

4. a kind of biomass energy circulation electrification technique as well as according to claim 3, it is characterized in that dry ash slag that will step (2) described biomass material gasification back produces and inflammable gas purify the wet lime-ash that the back produces and mix earlier, and then send into burning in the steam boiler (21).

5. biomass power generation system that is used for the described biomass energy circulation electrification technique as well as of claim 1, comprise gasifying electricity generation unit (1), described gasifying electricity generation unit (1) comprises the gasification oven (11) that links to each other successively, gas cleaning plant (12), gas internal combustion unit (13) and circulation cooling equipment, it is characterized in that described power generation system also comprises steam electric power unit (2), described steam electric power unit (2) comprises steam boiler (21), exhaust heat boiler (9) and Turbo-generator Set, the exhaust port of described gas internal combustion unit (13) is connected to exhaust heat boiler (9), and described gas cleaning plant (12) also is connected with treatment tank (14); The wet lime-ash floss hole that is used to discharge the high temperature Ash valves of dry ash slag and treatment tank (14) on the described gasification oven (11) is connected to the fuel inlet of steam boiler (21) jointly; Described exhaust heat boiler (9) links to each other with Turbo-generator Set with steam boiler (21) and Lian Houzai; The Turbo-generator Set of described steam electric power unit (2) comprises steam turbine (22) and coupled generator (23), be connected with steam turbine cooling waterpump (6) on the described steam turbine (22), this cooling waterpump is connected to the water cooling pond (7) of described circulation cooling equipment; Also be connected with vapour condenser (25) on the described steam turbine (22), described vapour condenser (25) is connected respectively to exhaust heat boiler (9) and steam boiler (21) by condensate pump (26), deaeration plant (27), feed water pump (28) and raw water service pump (30) successively; The intake pipe of the recirculated cooling water of described vapour condenser (25) links to each other with described water cooling pond (7) by steam turbine cooling waterpump (6), and the return pipe of the recirculated cooling water of described vapour condenser (25) is connected to the cooling intake pipe of gas internal combustion unit (13).

6. biomass power generation according to claim 5 system, it is characterized in that also being provided with heat exchanger (18) between described gasification oven (11) and the gas cleaning plant (12), the below of heat exchanger (18) is provided with water intake and water outlet, the water intake of heat exchanger (18) is connected to described feed water pump (28), and water outlet links to each other with the admission port of exhaust heat boiler (9), steam boiler (21) respectively through raw water service pump (30).

7. according to claim 5 or 6 described biomass power generation systems, it is characterized in that described power generation system also comprises hot water generator unit (4), it comprises hot-tub (43), heat exchanger (42) and the expansion power generation device that links to each other successively, described expansion power generation device also is connected with condenser (47) and working medium pump (46) in turn, described working medium pump (46) links to each other with the heat exchanger that is used to be connected hot-tub (43) (42) again, and this is used to connect the heat exchanger (42) of hot-tub and the water cooling pond (7) that condenser (47) is also connected to the circulation cooling equipment; The return pipe of described circulation cooling equipment links to each other with hot-tub (43).

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