CN103670551B - A kind of solar energy and living beings alliance organic rankine cycle system - Google Patents

Abstract

The invention provides an organic Rankine cycle system for joint supply of solar energy and biomass, which belongs to the field of energy and environment. Including heat transfer fluid circuit, organic working fluid circuit, cooling water circuit; heat transfer fluid circuit consists of solar collector, thermal fluid tank, first heat transfer fluid pressure pump, evaporator, preheater, second heat transfer The booster pump, biomass combustion furnace, cold fluid tank, third heat transfer fluid booster pump, the organic working medium circuit consists of evaporator, preheater, turbine, excitation generator, condenser, liquid storage tank, organic The working medium booster pump and the pipes connecting them are composed, and the cooling water circuit is composed of a condenser, a cooling tower, and a cooling water pump. The invention can store the heat transfer fluid heated by the sun during the day and use it at night. At the same time, the solar heat collector and the biomass burning furnace are arranged in parallel, and the loads of the solar heat collector and the biomass burning furnace are respectively adjusted according to the intensity of solar radiation. In the case of stable output of electric energy, fuel can be saved to the greatest extent.

Description

An Organic Rankine Cycle System for Cogeneration of Solar Energy and Biomass

technical field

The invention relates to an organic Rankine cycle system for joint supply of solar energy and biomass, belonging to the technical field of energy and environment.

Background technique

Power production is playing an increasingly important role in modern production and life. It can be said that power supply is the bottleneck of the development of the whole society. For a century, the power industry has relied heavily on fossil fuels. Although in recent years, with the application of supercritical Rankine cycle and other technologies, the efficiency of coal power has gradually increased (the latest technology in the world can now reach a thermal efficiency of nearly 50%), but The power industry is still the main emission source of serious environmental pollutants such as carbon dioxide and sulfur dioxide. At the same time, with the depletion of fossil fuels, the cost and difficulty of mining will increase. Therefore, we will increase efforts to develop new energy and reduce consumption of fossil fuels Relying on and using cleaner energy is an inevitable choice for human beings.

The radiant power of the sun reaches 3.8x1023kW, among which, the solar radiant energy flux intercepted by the earth is 1.7x1014kW, which is more than 5000 times greater than the sum of nuclear energy, geothermal and gravitational energy reserves. It is estimated that the energy radiated by the sun to the earth within one month can be as much as 10 times the total reserves of all non-renewable energy sources on the earth, including fossil fuels and atomic energy. Inexhaustible energy. my country is a country rich in solar energy resources. The annual sunshine hours of 2/3 of the country's land area are more than 2200h, and the total solar radiation per unit area is higher than 5016MJ/m2. Therefore, the study of solar power generation technology is of great significance to the sustainable development of our country and even all mankind. Solar power generation can convert solar energy into electrical energy without causing any pollution and pollution to the environment. Solar power generation is known as the most ideal way of power generation in the future. According to different conversion methods, it can be divided into photovoltaic power generation and light-thermal-electricity. Among them, photovoltaic power generation technology is relatively mature, but its efficiency is low and the initial investment is high.

Biomass resources mainly refer to agricultural and forestry wastes, manure from animal husbandry and urban solid wastes containing combustible components. my country is rich in biomass resources. According to statistics, the amount of rice straw discarded in rural areas in my country is as high as 700 million tons (calorific value is about 10.2×1015kJ), and forest industry waste is nearly 200 million tons (calorific value is about 3.1×1015kJ). Agricultural waste such as rice husks and straws. If these wastes are not properly recycled, they will become environmental hazards. The current biomass energy utilization technologies mainly include: direct combustion, the heat and steam generated by combustion can be used to generate electricity, or provide heat to users; biogas technology, the biogas produced by biomass can be used as domestic gas and power generation; biomass gasification technology, The combustible gas produced by gasification can be used for cooking, heating and crop drying, and can also be used as fuel for power devices such as internal combustion engines and gas turbines to output electricity or power; biomass pyrolysis technology is divided into dry distillation to produce water gas, charcoal and rapid Pyrolysis bio-oil technology; biomass liquefaction technology. In general, agricultural and forestry biomass needs to absorb carbon dioxide for photosynthesis during the growth process. The energy utilization and conversion system of this kind of biomass will not increase the total amount of carbon dioxide in the earth's atmosphere. Therefore, biomass energy utilization Technology research has become a hot spot in the research of new energy technology in the international community. At present, clean biomass combustion technologies, such as rural biogas technology and straw gasification technology, have matured, and related products are gradually being finalized and marketed.

Effectively coupling low-temperature solar energy and biomass energy to build a combined heat and power system can realize the complementary advantages of solar energy and biomass energy and ensure the stability and efficiency of the energy conversion system. It is expected to become an important technical measure for building a distributed energy supply system.

Contents of the invention

The purpose of the present invention is to provide an organic Rankine cycle system for joint supply of solar energy and biomass, which adopts the form of parallel arrangement of biomass combustion furnace and solar heat collector, and can adjust the load borne by the two according to the intensity of solar radiation. On the premise of stabilizing the output of electric energy, it can save fuel to the greatest extent. At the same time, the heat storage device is used to improve the heat utilization rate of the system.

The solution adopted to solve the technical problem of the present invention is: a solar energy and biomass joint supply organic Rankine cycle system, including a heat transfer fluid circuit, an organic working medium circuit, and a cooling water circuit; Heater 1, hot fluid tank 2, first heat transfer fluid pressure pump 3, evaporator 4, preheater 5, second heat transfer fluid pressure pump 6, biomass combustion furnace 7, cold fluid tank 8, the first Three heat transfer fluid pressurized pumps 9 are formed; the solar collector 1 outlet is connected to the cold fluid tank 8 outlet, the third heat transfer fluid pressurized pump 9 inlet, the hot fluid tank 2 inlets, and the evaporator 4 hot fluid side inlets through pipelines Connection, the outlet of the thermal fluid tank 2 is connected to the inlet of the first heat transfer fluid booster pump 3 through a pipeline, the outlet of the first heat transfer fluid booster pump 3 is connected to the inlet of the thermal fluid side of the evaporator 4 through a pipeline, and the thermal fluid side of the evaporator 4 The outlet is connected to the inlet of the hot fluid side of the preheater 5 through pipelines, and the outlet of the hot fluid side of the preheater 5 is connected to the inlet of the second heat transfer fluid booster pump 6 and the cold fluid tank 8 through pipelines, and the second heat transfer fluid is pressurized The outlet of the pump 6 is connected to the heat transfer fluid inlet of the biomass combustion furnace 7 through a pipeline, and the heat transfer fluid outlet of the biomass combustion furnace 7 is connected to the heat fluid side inlet of the evaporator 4 through a pipeline; the outlet of the cold fluid tank 8 is connected to the third heat transfer fluid through a pipeline. The inlet of the fluid pressure pump 9 is connected, and the outlet of the third heat transfer fluid pressure pump 9 is connected to the inlet of the solar collector 1 through pipelines; the organic working medium circuit is composed of the evaporator 4, the preheater 5, the turbine 10, and the excitation generator 11. Condenser 12, liquid storage tank 13, organic working medium booster pump 14 and the pipelines connecting them. The cold fluid side outlet of evaporator 4 is connected with the inlet of turbine 10 and the hot fluid side inlet of condenser 12 through pipelines. The outlet of turbine 10 is connected to the hot fluid side inlet of condenser 12 through pipelines, the hot fluid side outlet of condenser 12 is connected to the inlet of liquid storage tank 13 through pipelines, and the outlet of liquid storage tank 13 is connected to the inlet of organic working medium booster pump 14 through pipelines , the outlet of organic working medium booster pump 14 is connected to the cold fluid side inlet of preheater 5 through pipelines, the cold fluid side outlet of preheater 5 is connected to the cold fluid side inlet of evaporator 4 through pipelines, and the output shaft of turbine 10 is connected to the excitation generator Machine 11 is connected; the cooling water circuit is made up of condenser 12, cooling tower 15, cooling water pump 16, and cooling water pump 16 is connected between cooling tower 15 outlet and condenser 12 cold fluid side inlets by pipeline, condenser 12 cold fluid side outlets It is connected to the water distribution pipe at the upper end of the cooling tower through the pipe.

The fuel used in the biomass combustion furnace 7 is fuel diesel, heavy oil, methanol, ethanol, methane, natural gas, coal gas, dimethyl ether, biomass fuel or fuel made from biomass (such as biodiesel, biomass gasification combustible gas).

The organic working fluid in the organic working fluid circuit is R123, R245fa, toluene, butane, isobutane, pentane, isopentane, cyclopentane, heptane, R113, R11, cyclohexane, benzene, o-di Any one or more of toluene, ethylbenzene, 6-methyl-2-siloxane, 8-methyl-3-siloxane, 10-methyl-4-siloxane, 12-methyl-5-siloxane, R134a, R227ea any mixture.

The heat transfer working medium of the heat transfer fluid circuit is heat transfer oil.

The thermal fluid tank 2 adopts a cylindrical metal tank, and an insulating material is installed on the outside.

According to the fuel type selected by the biomass combustion furnace, the type of working medium selected by the heat transfer fluid circuit, and the type of working medium selected by the organic working medium circuit, the biomass combustion furnace and solar heat collector are installed according to the required power generation capacity , heat transfer fluid booster pump, hot fluid tank, cold fluid tank, turbine, excitation generator, evaporator, preheater, condenser, liquid storage tank, working fluid booster pump, cooling tower, cooling water pump and its Pipelines and accessories; calculate the filling amount of circulating working fluid according to the volume of each pipeline, and measure and fill the circulating working medium into the circulating pipeline.

The working principle of the present invention is: the heated heat transfer fluid coming out from the solar collector 1 is mixed with the heat transfer fluid coming out of the cold fluid tank 8 all the way through the pipeline to achieve the effect of preheating the cold fluid; It can be stored in the thermal fluid tank 2 (when the solar radiation intensity is too large); the other way enters the evaporator 4, and the thermal fluid stored in the thermal fluid tank 2 can be heated by the first heat transfer fluid when needed. The pressure pump 3 pressurizes and also enters the evaporator 4. The heat transfer fluid transfers heat to the organic working medium in the evaporator 4, and after it is evaporated, it comes out of the evaporator 4 and enters the preheater 5. In the preheater 5 The same release of heat preheats the organic working medium that is about to enter the evaporator 4, and then comes out from the preheater 4. At this time, according to the loads that the solar collector 1 and the biomass combustion furnace 7 bear respectively, the heat transfer fluid One path passes through the second heat transfer fluid booster pump 6 to pressurize and then enters the biomass combustion furnace 7 to heat and then enters the evaporator 4 to release heat; the other path enters the cold fluid tank 8, and then comes out of the cold fluid tank 8 and is heated The heat transfer fluid heated by the solar heat collector 1 is mixed and then pressurized by the third heat transfer fluid pressurization pump 9 and enters the solar heat collector 1 to be heated to complete a heat transfer fluid circuit cycle; the organic heat transfer fluid coming out of the evaporator 4 The working medium steam enters the turbine 10 all the way to expand and do work, and the output shaft work of the turbine 10 drives the excitation generator 11 to rotate and generate electricity; It also enters the condenser 12 to condense into a liquid, then comes out of the condenser 12 and enters the liquid storage tank 13, and then the liquid coming out of the liquid storage tank 13 is pressurized by the organic working medium pressure pump 14 and then enters the preheater 5 to absorb heat and preheat , and then re-enter the evaporator 4 to absorb heat and evaporate to complete an organic working fluid loop cycle; the cooling water from the cooling tower 15 is transported to the condenser 12 through the cooling water pump 16 to condense the working fluid in the organic working fluid loop, and then return The water distribution pipe of the cooling tower 15 enters the water collecting pan at the bottom of the tower after being cooled to complete a cooling water loop cycle.

This system adopts the layout of parallel arrangement of solar heat collector and biomass combustion furnace, and has heat storage device at the same time, which has the following beneficial effects:

(1) It is more convenient to adjust the load of solar collectors and biomass combustion furnaces;

(2) Can output electric energy stably;

(3) It can store heat energy at the peak of solar radiation and release heat energy when the solar radiation is weak, which improves the continuous energy supply capacity of the system and saves fuel to the greatest extent;

(4) Compared with the ordinary steam Rankine power generation cycle, the power generation efficiency is improved;

(5) Greatly reduced the generation and emission of harmful substances CO _X and SO _X in the power generation process;

(6) It can efficiently convert low-density solar energy with abundant resources and various low-grade fuels into electric energy;

(7) It is convenient to realize personalized power generation system, which is suitable for providing power to areas that are not suitable for centralized power supply or insufficient power supply, such as mountainous areas, pastoral areas, scattered islands, scattered farmhouses, remote geological parks, military bases that require extremely high power supply safety, etc. .

Description of drawings

Fig. 1 is a schematic diagram of the system structure of the present invention.

The labels in the figure are: 1-solar collector, 2-thermal fluid tank, 3-heat transfer fluid pressurized pump, 4-evaporator, 5-preheater, 6-heat transfer fluid pressurized pump, 7- Biomass combustion furnace, 8-cold fluid tank, 9-heat transfer fluid booster pump, 10-turbine (or expander), 11-excitation generator, 12-condenser, 13-liquid storage tank, 14-organic Working fluid booster pump, 15-cooling tower, 16-cooling water pump.

Detailed ways

The present invention will be further elaborated below in conjunction with the accompanying drawings and embodiments.

Example 1: An organic Rankine cycle system for combined solar energy and biomass is built in a certain area, and the output power of the motor is 20kW.

The organic Rankine cycle system for combined solar energy and biomass supply includes a heat transfer fluid circuit, an organic working fluid circuit, and a cooling water circuit; the heat transfer fluid circuit is composed of a solar collector 1, a thermal fluid tank 2, a first heat transfer Fluid booster pump 3, evaporator 4, preheater 5, second heat transfer fluid booster pump 6, biomass combustion furnace 7, cold fluid tank 8, third heat transfer fluid booster pump 9; solar heat collection The outlet of device 1 is respectively connected with the outlet of cold fluid tank 8, the inlet of the third heat transfer fluid pressure pump 9, the inlet of hot fluid tank 2, and the side inlet of evaporator 4 through pipelines, and the outlet of hot fluid tank 2 is connected with the first transfer fluid through pipelines. The inlet of the hot fluid booster pump 3 is connected, the outlet of the first heat transfer fluid booster pump 3 is connected to the hot fluid side inlet of the evaporator 4 through a pipeline, and the hot fluid side outlet of the evaporator 4 is connected to the hot fluid side inlet of the preheater 5 through a pipeline , the hot fluid side outlet of the preheater 5 is connected to the second heat transfer fluid pressurized pump 6 and the inlet of the cold fluid tank 8 through pipelines, and the second heat transfer fluid pressurized pump 6 outlet is transferred to the biomass combustion furnace 7 through pipelines The fluid inlet is connected, the heat transfer fluid outlet of the biomass combustion furnace 7 is connected to the hot fluid side inlet of the evaporator 4 through a pipeline; the cold fluid tank 8 is connected to the third heat transfer fluid booster pump 9 inlet through a pipeline, and the third heat transfer fluid The outlet of the booster pump 9 is connected to the inlet of the solar heat collector 1 through a pipeline; The outlet of the evaporator 4 on the cold fluid side is connected to the inlet of the turbine 10 and the inlet of the hot fluid side of the condenser 12 through pipelines, and the outlet of the turbine 10 is connected to the hot fluid side of the condenser 12 through pipelines. The inlet is connected, the outlet of the hot fluid side of the condenser 12 is connected to the inlet of the liquid storage tank 13 through a pipeline, the outlet of the liquid storage tank 13 is connected to the inlet of the organic working fluid pressure pump 14 through a pipeline, and the outlet of the organic working medium pressure pump 14 is connected to the pre- The inlet of the cold fluid side of the heater 5 is connected, the outlet of the cold fluid side of the preheater 5 is connected with the inlet of the cold fluid side of the evaporator 4 through pipelines, and the output shaft of the turbine 10 is connected with the excitation generator 11; the cooling water circuit is cooled by the condenser 12, A tower 15 and a cooling water pump 16 are formed. The cooling water pump 16 is connected between the outlet of the cooling tower 15 and the cold fluid side inlet of the condenser 12 through pipelines.

Biomass combustion furnace 7 uses combustible gas produced by straw gasification furnace as fuel, and Solutia synthetic heat transfer oil Therminol VP-1 is used as heat transfer fluid; hot fluid tank 2 and cold fluid tank 8 are 2m in diameter and 4m in height Cylindrical steel container covered with insulating material. High temperature oil pump for heat transfer fluid pressure pump, evaporator 4 and preheater 5 adopt plate heat exchanger, solar collector 1 adopts sleeve type vacuum tube heat pipe solar collector, sleeve type vacuum tube heat pipe solar collector The diameter of the heat collecting tube is 6.5cm, the length is 1.7m, 10 in each group, connected by a casing with a diameter of 50cm, a total of 5 groups, according to the solar collector 1 outlet-thermal fluid tank 2--the first heat transfer Fluid booster pump 3—evaporator 4—preheater 5—second heat transfer fluid booster pump 6—biomass combustion furnace 7—cold fluid tank 8—third heat transfer fluid booster pump 9—solar collector 1. The sequence of imports is to connect the oil circuit with hot-dip galvanized steel pipe.

The working medium of the organic working medium circuit is R123, the turbine (expander) adopts IT10 screw expander, and the net output power is 10Kw; the pressure of the working medium at the inlet of the organic working medium circuit expander is 0.97MPa, and the temperature is 110°C; the condenser 12 adopts The plate heat exchanger and the booster pump of the organic working medium adopt a high-pressure shielded pump. The sequence of the organic working medium circuit is: outlet of liquid storage tank 13—organic working medium booster pump 14—preheater 5—evaporator 4—turbine 10—excitation generator 11—condenser 12—inlet of liquid storage tank 13. The circuits are installed separately with copper tubes.

The cooling tower 15 is a low-temperature cooling tower LBCM-20 with a cooling water circulation flow rate of 20m ³ /h, the cooling water pump 16 is a 12KQL50/100-1.1/2 model, and the cooling water pipeline is made of seamless steel pipes. The connection sequence is: cooling tower 15 outlet --Cooling water pump 16—condenser 12—cooling tower 15 inlet sequence Install the cooling water circuit and required accessories.

All the above equipment and equipment accessories are connected according to Figure 1. After the installation is completed, nitrogen purging of the pipeline is carried out, the organic working medium circuit is vacuumed, and R123, heat transfer oil and tap water are filled into the corresponding pipelines as required.

Embodiment 2: The organic Rankine cycle system for combined solar energy and biomass supply is the same as that of Embodiment 1, and the working medium of the organic working medium circuit is R245fa.

Embodiment 3: This solar energy and biomass co-providing organic Rankine cycle system is the same as embodiment 1, and the working fluid of the organic working fluid circuit adopts R123, R245, butane, respectively according to the volume ratio of 30%, 25%, and 45%. mixed.

The specific embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned embodiments, and can also be made without departing from the gist of the present invention within the scope of knowledge possessed by those of ordinary skill in the art. Variations.

Claims (5)

1. An organic Rankine cycle system for joint supply of solar energy and biomass, characterized in that: it includes a heat transfer fluid circuit, an organic working medium circuit, and a cooling water circuit; the heat transfer fluid circuit is composed of a solar heat collector (1), Thermal fluid tank (2), first heat transfer fluid pressurized pump (3), evaporator (4), preheater (5), second heat transfer fluid pressurized pump (6), biomass burner (7 ), cold fluid tank (8), the third heat transfer fluid pressurized pump (9); (9) Inlet, thermal fluid tank (2) inlet, evaporator (4) thermal fluid side inlet connection, thermal fluid tank (2) outlet is connected to the inlet of the first heat transfer fluid booster pump (3) through the pipeline, the first The outlet of the heat transfer fluid booster pump (3) is connected to the hot fluid side inlet of the evaporator (4) through a pipeline, and the hot fluid side outlet of the evaporator (4) is connected to the hot fluid side inlet of the preheater (5) through a pipeline to preheat The outlet of the hot fluid side of the device (5) is connected to the inlet of the second heat transfer fluid booster pump (6) and the cold fluid tank (8) through pipelines, and the outlet of the second heat transfer fluid booster pump (6) is connected to the biomass tank (6) through pipelines. The heat transfer fluid inlet of the combustion furnace (7) is connected, the heat transfer fluid outlet of the biomass combustion furnace (7) is connected to the hot fluid side inlet of the evaporator (4) through a pipeline; the outlet of the cold fluid tank (8) is connected to the third heat transfer fluid through a pipeline The inlet of the fluid booster pump (9) is connected, and the outlet of the third heat transfer fluid booster pump (9) is connected to the inlet of the solar heat collector (1) through a pipeline; the organic working medium circuit is composed of the evaporator (4), preheater ( 5), turbine (10), excitation generator (11), condenser (12), liquid storage tank (13), organic working medium booster pump (14) and pipelines connecting them, evaporator (4 ) The outlet of the cold fluid side is connected to the inlet of the turbine (10) and the inlet of the hot fluid side of the condenser (12) through the pipeline, the outlet of the turbine (10) is connected to the inlet of the hot fluid side of the condenser (12) through the pipeline, and the condenser (12) ) The thermal fluid side outlet is connected to the inlet of the liquid storage tank (13) through a pipeline, the outlet of the liquid storage tank (13) is connected to the inlet of the organic working medium booster pump (14) through a pipeline, and the outlet of the organic working medium booster pump (14) is connected to the The pipeline is connected to the inlet of the cold fluid side of the preheater (5), the outlet of the cold fluid side of the preheater (5) is connected to the inlet of the cold fluid side of the evaporator (4) through the pipeline, and the output shaft of the turbine (10) is connected to the excitation generator ( 11) Connection; the cooling water circuit is composed of a condenser (12), a cooling tower (15), and a cooling water pump (16). The cooling water pump (16) is connected to the outlet of the cooling tower (15) and the cold fluid of the condenser (12) Between the side inlets, the side outlet of the cold fluid of the condenser (12) is connected to the water pipe at the upper end of the cooling tower through pipes. 2. The organic Rankine cycle system for co-supplying solar energy and biomass according to claim 1, characterized in that: the fuel used in the biomass combustion furnace (7) is fuel diesel, heavy oil, methanol, ethanol, methane, natural gas , gas, dimethyl ether, biomass fuel or fuel made from biomass. 3. The organic Rankine cycle system for joint supply of solar energy and biomass according to claim 1, characterized in that: the organic working medium in the organic working medium loop is R123, R245fa, toluene, butane, isobutane, amyl Alkane, isopentane, cyclopentane, heptane, R113, R11, cyclohexane, benzene, o-xylene, ethylbenzene, 6 methyl 2 siloxane, 8 methyl 3 siloxane, 10 methyl Any one of 4 siloxane, 12 methyl 5 siloxane, R134a, R227ea or any mixture of several. 4. The organic Rankine cycle system for combined solar energy and biomass supply according to claim 1, characterized in that: the heat transfer working medium of the heat transfer fluid circuit is heat transfer oil. 5. The organic Rankine cycle system for cogeneration of solar energy and biomass according to claim 1, characterized in that: the thermal fluid tank (2) is a cylindrical metal tank, and an insulating material is installed on the outside.