Biomass power generation's future prospect 02

Biomass power generation's unit selection and form

Biomass has four forms of power generation

Biomass direct combustion power generation biomass direct combustion power generation technology refers to the use of biomass combustion heat energy into steam for power generation. In principle, it is no different from coal-fired power generation. Its principle is to convert the chemical energy stored in biomass into internal energy of high-temperature and high-pressure steam through combustion in a specific steam boiler, then into kinetic energy of rotor through steam turbine, and finally into clean and efficient electric energy through generator.  Direct combustion power generation is to directly burn biomass in a boiler to produce steam and drive steam turbines and generators to generate electricity. The key technologies of biomass direct combustion power generation include biomass raw material pretreatment, boiler anti-corrosion, boiler raw material applicability, fuel efficiency, steam turbine efficiency and so on.

Biomass gasification power generation biomass gasification power generation technology is to convert biomass into combustible gas, reuse combustible gas, and use gas-fired power generation equipment to generate electricity. Its principle is to convert the chemical energy stored in biomass into combustible gas through combustion in a specific gasifier, and then into clean and efficient electric energy through gas engine power generation system. Biomass gasification power generation technology refers to that biomass is converted into gas fuel in the gasifier, and then directly enters the gas engine for combustion and power generation after purification, or directly enters the fuel cell for power generation. One of the key technologies of gasification power generation is gas purification. The gasified gas contains certain impurities, including ash, coke and tar, which need to be removed by the purification system to ensure the normal operation of power generation equipment.

Biogas power generation technology is a biogas utilization technology with the continuous development of comprehensive utilization of biogas. It uses biogas on the engine and is equipped with comprehensive power generation device to generate electric energy and heat energy. It is an important way to make effective use of biogas. Biogas power generation is a biogas utilization technology with the continuous development of biogas comprehensive utilization technology. Its main principle is to drive the generator set to generate electricity by using the biogas produced by anaerobic fermentation of a large number of organic wastes in industry, agriculture or urban life. The equipment used for biogas power generation is mainly internal combustion engine, which is generally transformed from diesel unit or natural gas unit. Biogas is mostly produced in sewage treatment plants, landfills, wineries, food processing plants, farms, etc.

Biogas is a combustible gas produced by the decomposition and transformation of organic matter by a variety of microorganisms under anaerobic conditions. It belongs to the category of biomass energy. The main component is methane and carbon dioxide, in which the content of methane is about 50% ~ 70%, the content of carbon dioxide is 30% ~ 40% (volume ratio), and there is a small amount of hydrogen sulfide, nitrogen, oxygen, hydrogen and other gases, accounting for about 10% ~ 20% of the total content. Methane burns with fire in the air, turns into carbon dioxide and water, and releases energy. Biogas fermentation, also known as anaerobic digestion, anaerobic fermentation or methane fermentation, refers to a complex biochemical process in which organic matter is finally formed into mixed gases (biogas) such as methane and carbon dioxide through the decomposition and metabolism of various microorganisms with a wide variety, huge quantity and different functions under certain water, temperature and anaerobic conditions.

Biomass mixed combustion power generation refers to the application of biomass raw materials to coal-fired power plants, using biomass and coal for power generation. The principle is that biomass and coal are burned together in the boiler and converted into internal energy of high-temperature and high-pressure steam, then converted into kinetic energy of rotor through steam turbine, and finally converted into electric energy through generator. The mixed combustion technology of biomass and coal can be divided into two forms: direct mixed combustion and gasification utilization. Biomass can also be mixed with coal as fuel for power generation, which is called biomass mixed combustion power generation technology. There are two main ways of mixed combustion. One is that biomass is directly mixed with coal and then put into combustion. This method has high requirements for fuel treatment and combustion equipment, which can not be adopted by all coal-fired power plants; One is the mixed combustion of gas and coal produced by biomass gasification, which is burned in the mixed combustion system, and the generated steam is sent to the steam turbine generator set together.

1. Abide by the principle of "heat and power generation". Due to the large industrial and heating heat load in the city, according to the characteristics of heat load and from the perspective of ensuring investment benefits, the installation scheme should be determined on the basis of meeting the short-term heat load demand and in combination with the long-term heat load scale and power load demand planning of the city, so as to finally realize the purpose of cogeneration and central heating.

2. In order to ensure the safety and reliability of heating, the capacity and number of units should be reasonable as far as possible to avoid excessive impact on heating when the largest unit is shut down.

3. In order to improve the efficiency of thermal power plant, higher initial parameters should be selected for main equipment.