CN210068320U

CN210068320U - Combined power generation system for biomass gasification driven by solar energy

Info

Publication number: CN210068320U
Application number: CN201920945206.XU
Authority: CN
Inventors: 康磊
Original assignee: 康磊
Current assignee: Jiangsu LUHANG Power Technology Co., Ltd
Priority date: 2019-06-22
Filing date: 2019-06-22
Publication date: 2020-02-14
Anticipated expiration: 2029-06-22

Abstract

The utility model discloses a solar drive biomass gasification's cogeneration system, what solve is that present independent system produces the electric efficiency low and unmatched problem of input/output. The product comprises a gasification reactor, a purifier, an SOFC fuel cell and a solar energy light-gathering heat absorberThe gasification reactor is connected with a waste heat boiler, the waste heat boiler is also connected with a purifier, the SOFC fuel cell is respectively connected with a solar light-gathering heat absorber and a synthesis gas compressor, the synthesis gas compressor is connected with the purifier, the solar light-gathering heat absorber is connected with an air compressor, and the waste heat boiler and the SOFC fuel cell are both connected with a combustion chamber. The product utilizes two renewable energy sources, combines the respective advantages of a solar photo-thermal system, a fuel cell system and a tail gas power system, meets the high-temperature requirement of gasification reaction, supplements the temperature of working media at each stage to improve the quality of the working media, reasonably and gradiently utilizes the energy of each product section, and reduces the energy consumption to the maximum extent

Loss, and realizing the efficient conversion of energy of each temperature section.

Description

Combined power generation system for biomass gasification driven by solar energy

Technical Field

The utility model relates to a power generation field specifically is a solar drive biomass gasification's combined power generation system.

Background

The environmental problem of energy facing human beings is becoming more severe, and there is an urgent need for a clean energy to gradually replace the existing fossil energy used on a large scale. The solar energy has attracted people's attention and research make internal disorder or usurp due to its huge total amount and wide distribution. A large portion of the energy of the earth on which humans live is derived from solar energy. Research shows that solar energy enters a rapid development stage in the century, the proportion of the solar energy is estimated to reach 30% in the year 2050, and the nuclear energy is second only, and the nuclear energy is replaced by the solar energy at the end of the century. Currently, solar technologies include photovoltaic system power generation, solar concentrator system power generation, and a wide variety of solar thermal storage devices. Solar energy has many advantages and is a new clean energy which is worth researching and developing. The storage of solar energy is abundant, and compared with the life of human beings, solar energy is inexhaustible. Solar energy is constantly transmitted from the sun to the earth every year. There may be differences in solar energy distribution between different regions on the earth, but the distribution of solar energy across the globe is relatively uniform relative to other renewable energy sources. The solar energy is environment-friendly energy like other clean energy, and does not produce any pollution to the environment.

However, the solar energy utilization technology still faces the problems of low efficiency, high cost, difficult energy storage, unstable energy supply and the like after years of development, so that the development of the solar energy utilization technology is severely restricted.

Biomass refers to various organisms formed by photosynthesis, and carriers of biomass energy are organic substances and compounds composed of carbon and hydrogen elements. Compared with other renewable energy sources such as solar energy or wind energy, the biomass is a renewable energy source which can be stored, transported and transported, and is also the only renewable carbon source, and the carbon balance of the ecosphere is maintained in the utilization process of the biomass. The biomass resources in China are rich, the energy utilization potential is huge, in the aspect of forestry residues, the area of the current forest land in China is 3.04 hundred million hectares, and the resource quantity of energy utilization such as firewood forest, forestry 'three residues', wood processing residues and the like is about 3.5 hundred million tons/year. The quantity of excrement resources of the bred livestock is 8 hundred million tons per year, and the production potential of the biogas reaches 200 billion cubic meters. Urban garbage increases along with urbanization process year by year, and the current rubbish volume of collecting is close 3 hundred million tons, and the usable amount is about 50%, and increases rapidly with 10% increase rate each year, and wherein more than 70% can regard as burning power generation fuel, and rubbish from cooking can regard as biogas or biodiesel raw materials in addition, and the annual acquirable volume reaches 400 ten thousand tons. From the variety, the first three-position straw resources are corn rice (2.65 hundred million tons), straw (2.05 hundred million tons) and wheat rice (1.50 hundred million tons); in addition, the resource amount of oil crop rice (mainly rape and peanut) and cotton stalk respectively reaches 3737 ten thousand tons and 2584 ten thousand tons. Biomass, as a renewable energy source, can be utilized by a variety of technical means, including direct combustion, thermochemistry, and biochemistry of biomass. In contrast, biomass combustion can only provide high-temperature heat energy and is difficult to meet the modern diversified energy demand, so that biomass can be converted into various high-quality gas fuels or liquid fuels such as bioethanol, biodiesel, biogas, synthetic gas and tar in biochemical and thermochemical manners, and the biomass can be used for replacing fossil energy and applied to the fields of electric power, transportation, urban gas and the like.

The hydrogen as a clean fuel overcomes the problem of environmental pollution caused by the discharge of pollutants during the use of fossil fuels. Meanwhile, hydrogen energy is also considered as another energy carrier to propel airplanes, automobiles and any stationary energy systems using fuel cells. Hydrogen energy is therefore an ideal energy carrier to store energy for various applications. However, hydrogen monomer is almost nonexistent on earth, and as a secondary energy source, it must be produced by consuming other energy sources. At present, the hydrogen is prepared in various ways, such as decomposing fossil fuel, reforming the fossil fuel with water vapor, producing hydrogen by coal gasification, producing hydrogen by water electrolysis and producing hydrogen by solar thermochemical method. In recent years, with the great improvement of the light gathering technology and the manufacturing process level, the solar thermochemical biomass gasification hydrogen production method gradually enters the field of people and is subjected to a great deal of research. The solar thermochemical hydrogen production is an energy storage mode in which concentrated solar energy is used as a heat source to drive chemical reaction to store the solar energy at high density, so that conversion from the solar energy to the chemical energy is realized. The biomass and water are directly decomposed by utilizing high-level solar energy to generate H2 and CO, and the H2 and CO are used as raw materials to synthesize other energy situations which are convenient to store, or the gas is used as energy for burning electricity and heat engines.

SOFC (solid oxide fuel cell) has wide fuel applicability, high operation temperature, high power generation efficiency, cleanness and no pollution, can utilize various synthesis gases as fuel to carry out high-efficiency power generation, has wide fuel application range and high operation temperature of a galvanic pile, has great potential in combination with various sensible heat in the process of hydrogen production by solar chemical generation, and people also carry out research in relevant aspects.

SUMMERY OF THE UTILITY MODEL

An object of the embodiment of the utility model is to provide a solar drive biomass gasification's combined power generation system to solve the problem that proposes among the above-mentioned background art.

In order to achieve the above object, the embodiment of the present invention provides the following technical solutions:

a solar energy driven biomass gasification combined power generation system comprises a gasification reactor, a purifier, an SOFC fuel cell and a solar energy condensation heat absorber, wherein the gasification reactor is connected with a waste heat boiler, the waste heat boiler is also connected with the purifier, the SOFC fuel cell is respectively connected with the solar energy condensation heat absorber and a synthesis gas compressor, the synthesis gas compressor is also connected with the purifier, the solar energy condensation heat absorber, the synthesis gas compressor and the SOFC fuel cell are all connected with a gas turbine, the solar energy condensation heat absorber is also connected with the tail end of the gas turbine and the front end of the waste heat boiler, the steam-water gas of a preheating boiler is connected with a steam turbine and a water feeding pump, the SOFC fuel cell has higher power generation efficiency (45-60%) at 750 ℃ and 1000 ℃, the SOFC fuel cell in the product adopts yttria stabilized zirconia as electrolyte, anode perovskite ceramic, and the cathode is perovskite material, the CO can participate in electrochemical reaction, and CO purification treatment is not needed.

As a further scheme of the embodiment of the utility model: the solar energy light-gathering heat absorber is connected with the front end of the turbine and the front end of the waste heat boiler, and can convey redundant heat to the waste heat boiler, the waste heat boiler is connected with a steam-water heating pipeline of the waste heat boiler, when the SOFC fuel cell is in a protection or preheating state, the synthesis gas is introduced into the combustion chamber to be combusted to provide energy for the circulation of the whole system, and when the SOFC fuel cell works, the synthesis gas does not need to be directly combusted; the excess heat can be better utilized.

As a further scheme of the embodiment of the utility model: the steam-water system of the waste heat boiler is respectively connected with the steam turbine and the water feeding pump, the steam turbine and the water feeding pump are both connected with the condenser, and therefore the energy of the waste heat boiler can be converted into mechanical energy, and the energy is utilized to the maximum.

As a further scheme of the embodiment of the utility model: the gas turbine comprises an air compressor, a turbine and a combustion chamber, the turbine and the air compressor are coaxial, the power generated by the turbine is partially consumed by air compression, and the flue gas of the gas turbine is heated by the solar light-gathering heat absorber and then enters the waste heat boiler, so that energy can be provided for the SOFC fuel cell and the waste heat boiler, and the energy utilization rate is improved.

As a further scheme of the embodiment of the utility model: the gasification reactor adopts a groove type solar gasification reactor, can accept biomass, solar energy and steam as energy sources, and has a wide application range, wherein part of the gasified waste heat boiler is used for gasification reaction heat after solar photo-thermal conversion, the other part of the gasified waste heat boiler exists in a sensible heat form of synthesis gas, the waste heat boiler adopts a gasified waste heat boiler, the synthesis gas generated by the gasification reactor can be used as the energy source, so that the effect of recycling the energy is achieved, the solar light-gathering heat absorber adopts a groove type solar light-gathering heat absorber, the heat absorber mainly supplements heat for a downstream system to improve the grade, the heat absorber is matched with the groove type solar gasification reactor for use, solar radiation is heat energy, secondary radiation reaction is carried out, one part of the heat absorber is used for reduction reaction, the other part of.

Compared with the prior art, the utility model discloses the beneficial effect of embodiment is:

the product couples a solar photo-thermal system, a biomass gasification reforming system, an SOFC fuel cell, an impeller mechanical power generation terminal and the like, utilizes two renewable energy sources, combines the advantages of the solar photo-thermal system, the fuel cell system and a tail gas power system, meets the high-temperature requirement of gasification reaction, supplements the temperature of working media at each stage to improve the quality of the working media, reasonably and gradiently utilizes the energy of each product section, and reduces the energy consumption to the maximum extent

Loss; the 'thermochemical reaction before combustion' and 'thermal cycle after combustion' are combined to realize the high-efficiency conversion of energy of each temperature section; the solar light heat energy, SOFC power generation, a gas turbine and a steam turbine drive multi-channel power generation to keep the total energy utilization efficiency most reasonable, and the defect of low efficiency of the traditional photovoltaic and photo-thermal power generation is overcome;

the product utilizes the vaporization heat source provided by solar energy, the effective utilization rate of biomass is improved by increasing the gasification temperature, and CH in the synthesis gas is reduced₄And CO₂The content improves the heat value of the synthesis gas, and larger sensible heat is available for the rear end to utilize;

the SOFC fuel cell in the product has strong adaptability to non-hydrogen gas, so that the hydrocarbon proportion does not need to be adjusted by conversion reaction, compared with the traditional biomass gas for synthesizing methanol, the non-adjusted hydrocarbon proportion can reduce the heat consumption of a system, the heating of the cathode gas of the electric pile is to absorb the solar energy for heat collection, and the incompletely reacted gas in the SOFC fuel cell is output by electric energy generated by the secondary combustion of a turbine;

the product can utilize solar energy to the maximum extent, any node needing to improve working medium circulation temperature is heated by the solar energy light-gathering heat absorber, the preheating flow of the SOFC fuel cell is simplified, meanwhile, the inlet temperature of the turbine is also improved, the efficiency of the gas turbine is improved along with the improvement of the temperature, the inlet temperature of the steam turbine can be increased to the maximum extent after the quality of turbine exhaust steam is improved by the solar energy light-gathering heat absorber, the loss of wet steam is reduced by a large superheat degree, and the heat balance efficiency of the system reaches 31.77%;

the product utilizes two renewable resources alternately through a complementary coupled power generation system, improves the solar energy proportion in input energy to the maximum extent, enables the solar energy proportion to reach 47.5% under a steady-state working condition, and gasifies biomass into CO and H efficiently₂And the use effect is good.

Drawings

FIG. 1 is a schematic diagram of a solar-driven biomass gasification cogeneration system.

FIG. 2 is a graph of the major gas components at each gasification reaction temperature in a solar driven biomass gasification combined power generation system.

Wherein: the system comprises a gasification reactor 1, a waste heat boiler 2, a purifier 3, a synthesis gas compressor 4, a SOFC fuel cell 5, a solar energy light-gathering heat absorber 6, an air compressor 7, a waste heat boiler 8, a combustion chamber 9, a turbine 10, a steam turbine 11, a condenser 12 and a water feeding pump 13.

Detailed Description

The technical solution of the present patent will be described in further detail with reference to the following embodiments.

Example 1

A solar energy driven biomass gasification combined power generation system comprises a gasification reactor 1, a purifier 3, an SOFC fuel cell 5 and a solar energy light-gathering heat absorber 6, wherein the gasification reactor 1 is connected with a waste heat boiler 2, the waste heat boiler 2 is also connected with the purifier 3, the SOFC fuel cell 5 is respectively connected with the solar energy light-gathering heat absorber 6 and a synthesis gas compressor 4, the synthesis gas compressor 4 is also connected with the purifier 3, the solar energy light-gathering heat absorber 6 is connected with an air compressor 7, the waste heat boiler 2 and the SOFC fuel cell 5 are both connected with a combustion chamber 9, an energy source generates gasification reaction in the gasification reactor 1 to generate high-temperature synthesis gas, and high-temperature sensible heat is utilized by means of waste heat recovery devices such as the waste heat boiler 2; the generated synthesis gas is used as the anode fuel of the SOFC fuel cell 5, the tail gas is used as the energy source of the combined cycle power system, the high-temperature section of the heat energy after combustion is utilized by the gas turbine, and the low-temperature section is utilized by the steam turbine for power generation, so that the utilization effect is good.

In order to better utilize the redundant heat, the solar energy light-gathering heat absorber 6 is connected with the waste heat boiler 8, the redundant heat can be transmitted to the waste heat boiler 8, and the waste heat boiler 8 is connected with the waste heat boiler 2 to realize cyclic utilization.

Further, the exhaust-heat boiler 8 is respectively connected with the steam turbine 11 and the feed pump 13, and the steam turbine 11 and the feed pump 13 are both connected with the condenser 12, so that the energy of the exhaust-heat boiler 8 can be converted into mechanical energy, and the energy can be utilized to the maximum.

Example 2

In order to improve the energy utilization rate, the solar energy heat-collecting and heat-absorbing device 6 is connected with the combustion chamber 9 through the turbine 10, and the energy in the combustion chamber 9 can be reused to provide energy for the SOFC fuel cell 5 and the waste heat boiler 8.

Furthermore, the gasification reactor 1 adopts a groove type solar gasification reactor, biomass, solar energy and steam can be accepted as energy sources, the application range is wide, the waste heat boiler 2 adopts a gasification waste heat boiler, synthesis gas generated by the gasification reactor 1 can be utilized as the energy source, the effect of recycling energy is achieved, and the solar light-gathering heat absorber 6 adopts a groove type solar light-gathering heat absorber and is matched with the groove type solar gasification reactor for use, so that the effect is better.

The embodiment of the utility model provides a theory of operation is: the gasification reaction in the gasification reactor 1 is a strong heat absorption type reduction reaction, the heat required by the reaction comes from a solar light-gathering heat collector, and meanwhile, water vapor needs to be introduced into the reactor as a gasification medium, and the gasification reaction process is as follows:

C+H₂O→CO+H₂△_rH＝131.29KJ/mol

C+CO₂→2CO △_rH＝131.29KJ/mol

C+2H₂→CH₄△_rH＝131.29KJ/mol

CH₄+H₂O→CO+3H₂△_rH＝131.29KJ/mol

CO+H₂O→CO₂+H₂△_rH＝131.29KJ/mol。

in the heating process of the gasification reactor 1, the pyrolysis reaction of the volatile analysis of the biomass is mainly carried out in the low-temperature reaction section (< 412 ℃); mainly divided into four stages, a) when the temperature is less than 240 ℃, the biomass is depolymerized and recombined; b) the decomposition reaction is carried out at the temperature of 240-412 ℃, and a large amount of volatile gas is separated out; c) the biomass is carbonized at the temperature of 412-600 ℃ and simultaneously the generation of ash is accompanied; the first three stages are referred to as low temperature stage pyrolysis reactions; d) the temperature is 600-850 ℃, the biomass semicoke and the steam are subjected to gasification reaction, and the zone is called high-temperature gasification reaction; therefore, the solar energy light-gathering heat absorber 6 needs to focus to generate a high-temperature heat source of 1000-; the gasifying agent in the gasification reactor 1 is derived from steam evaporated by the sensible heat of the synthesis gas. CO and H in syngas₂The ratio is adjusted by the amount of steam supplied.

The synthetic gas enters the waste heat boiler 2 at the high temperature of 850 ℃ for heat exchange, ash is removed, harmful gas is filtered, and then the pressure is increased, so that the synthetic gas containing CO/H₂The gas with higher concentration is introduced into the anode of the SOFC fuel cell 5, and the SOFC fuel cell 5 is connected with H₂The adaptability of other gas fuel is high, the fuel is ionized at the anode and reacts with oxygen ions passing through the electrolyte to generate water; an electric current path is formed outside to output electric energy, and the other path of air comes from an eddyThe wheel 10 drives an air compressor 7, compressed gas is heated by solar energy and then enters the cathode of the SOFC fuel cell 5, air preheating of the cathode is part of solar energy condensation coupling, heat of a high-temperature section of the solar energy is mainly utilized, and at the moment, gas of the cathode and the anode entering the SOFC fuel cell 5 is 700-800 ℃; the fuel conversion efficiency of the electric pile can reach more than 80 percent at the temperature;

the anode side reaction equation is:

O^2-+CO＝CO₂+2e^-

O^2-+H₂＝H₂O+2e^-

4O^2-+CH₄＝CO₂+2H₂O+8e^-

the incompletely reacted gas contains partial combustible gas, the incompletely reacted gas is directly introduced into a combustion chamber 9 at high temperature, the temperature of the gas after high-temperature combustion can reach 1400K, the highest efficiency of the current fossil fuel is gas-steam combined cycle, the thermal cycle of the high-temperature tail gas of the system is the same as that of the steam-combustion combined cycle, sensible heat (800-1400K) in a high-temperature section is utilized, and sensible heat (400-800K) in a low-temperature section in the flue gas is utilized by a steam system consisting of a waste heat boiler 8 and a steam turbine 11;

the solar energy improves the energy utilization quality of each stage; in order to keep the temperature balance of the cathode and the anode of the SOFC fuel cell 5, the cathode side inlet air temperature is equivalent to the anode inlet air temperature, and the cathode side inlet air temperature is increased by heating the solar energy light-gathering heat absorber 6; the exhaust steam of the combined cycle gas turbine is further improved to 800-1000K by heating through the solar energy light-gathering heat absorber 6, so that the heat efficiency and the steam superheat degree of heat exchange equipment can be improved, and the wet steam loss of the steam turbine 11 is reduced; the coupling of solar energy, the SOFC fuel cell 5 and tail gas combined cycle realizes the high-efficiency utilization of biomass fuel, the saving of process raw materials and the increase of output power;

the sulfur content of the purified biomass gasification synthesis gas is less than 1 ppm;

in the biomass gasification process, with the increase of the gasification temperature, CO in the synthesis gas₂And CH₄The content of (A) is gradually reduced, and when the gasification temperature reaches over 1000K, H₂Has a reduced content of (C) and a reduced CO concentrationThe temperature of the gasification system is increased, but both the temperature and the reaction enthalpy of reactants are stable, the sensible heat and the reaction enthalpy of the reactants are increased along with the increase of the gasification reaction temperature of the whole system, so that the share of solar energy in the energy supply of the system is increased, the gasification temperature is required to be at least over 1000K, and the gasification temperature of the system is 1200K;

the input energy is biomass and the solar energy is renewable energy, and CO is discharged externally by the system₂The unit discharge amount is 0.57Kg (CO)₂) KW h, much lower than CO of conventional coal-fired units₂The exhaust, taking a system with 20MW net output power as an example herein, details the thermal efficiency of the system, and the heat loss of the system mainly occurs in the solar energy light-gathering heat absorber 6, the condensation process of steam, the sensible heat loss of synthesis gas and the heat loss of exhaust gas; the energy conversion of the steam-gas combined cycle system mainly comprises combustion, air compression, smoke expansion, solar energy heat compensation, heat exchange of a waste heat boiler 8 and steam expansion work, the combustion chamber 9 combusts high-temperature tail gas to release heat for heating working media, irreversible loss can be generated in the combustion chamber 9, a steam turbine 11 is used as equipment for converting energy into driving energy, an air compressor 7 receives part of the driving energy to provide compressed air for the system, the compressed gas passes through a galvanic pile through the heat compensation of a solar energy light-gathering heat absorber 6, the smoke of the turbine 10 is compensated by the solar energy light-gathering heat absorber 6 and then enters the waste heat boiler 8, and solar energy is input for the system in the process; the heat compensation of the two parts is completed by the solar energy light and heat collecting and absorbing device 6, and the specific heat balance is shown in table 1.

TABLE 1 thermal equilibrium analysis

As can be seen from Table 1, the product has good use effect.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. The utility model provides a solar energy drive biomass gasification's cogeneration system, includes gasification reactor (1), clarifier (3), SOFC fuel cell (5) and solar energy spotlight heat absorber (6), its characterized in that, gasification reactor (1) links to each other with waste heat boiler (2), and waste heat boiler (2) still links to each other with clarifier (3), and SOFC fuel cell's (5) negative pole and positive pole link to each other with solar energy spotlight heat absorber (6) and synthetic gas compressor (4) respectively, and synthetic gas compressor (4) still link to each other with clarifier (3), and solar energy spotlight heat absorber (6), synthetic gas compressor (4) and SOFC fuel cell (5) all link to each other with gas turbine.

2. The combined power generation system for solar driven biomass gasification according to claim 1, characterised in that the gas turbine comprises an air compressor (7), a combustion chamber (9) and a turbine (10).

3. The solar driven biomass gasification combined power generation system according to claim 2, wherein the solar energy light-gathering heat absorber (6) is connected with the tail end of the turbine (10) and the front end of the waste heat boiler (8), and the waste heat boiler (8) is connected with the steam-water heating pipeline of the waste heat boiler (2).

4. The solar-driven biomass gasification combined power generation system according to claim 3, wherein the steam-water system of the waste heat boiler (8) is connected with a steam turbine (11) and a feed water pump (13), and the steam turbine (11) and the feed water pump (13) are both connected with a condenser (12).

5. The solar driven biomass gasification combined power generation system according to claim 1, wherein the gasification reactor (1) is a trough solar gasification reactor, the waste heat boiler (2) is a gasification waste heat boiler, and the solar concentrating heat absorber (6) is a trough solar concentrating heat absorber.