Development of biomass power generation in China

2.4 Biogas power generation

Biogas power generation mainly uses biogas generated by anaerobic fermentation treatment of a large amount of organic waste in industrial and agricultural or urban life to drive generator sets to generate electricity.

China's biogas power generation technology research and development has more than 20 years of history, the current domestic biogas power generation project is mainly combined with high concentration of degradable organic wastewater treatment construction, belongs to the product of wastewater treatment, the largest unit in normal operation in China is 10,000 kW · h, there is no larger biomass biogas generator set.

2.5 Waste-to-Power generation

Waste power generation includes waste incineration power generation and waste gasification power generation, which can not only solve the problem of waste disposal, but also recycle the energy in the waste and save resources. The waste incineration technology mainly includes layer combustion technology, fluidized bed combustion technology, rotary combustion technology and so on. The gasification and melting incineration technology developed in recent years includes the gasification of garbage at a temperature of 450 ° C ~ 640 ° C and the melting combustion of carboniferous ash residue above 1300 ° C. The waste treatment is thorough, the process is clean, and some resources can be recovered, which is considered to be the most promising waste power generation technology.

By the end of 2009, the total number of waste incineration plants in China had reached more than 80, the daily waste incineration treatment capacity exceeded 55,000 tons, and the total installed capacity of waste incineration power generation reached 1.25 million kW · h. In eastern China, especially in coastal cities, waste disposal is gradually changing from landfill to incineration. With the continuous development of waste recycling, treatment, transportation, comprehensive utilization and other aspects of technology, waste incineration power generation has a broad market prospect.

3 Problems and development prospects of biomass power generation in China

3.1 Problems in biomass power generation

From the construction and operation of domestic biomass power plants, it can be seen that the factors restricting the development of China's biomass power generation industry are mainly as follows.

(1) High construction and operation costs. The unit cost of biomass power plant is 10,000 to 15,000 yuan /kW · h, and the cost of combustion equipment is high. At the same time, due to the low energy density, the cost of pre-processing, transportation and storage of biomass fuel is also high. In addition, the effective tax rate of biomass power plants is 11%, while traditional thermal power plants are about 6% to 8%, and small hydropower is about 3%.

(2) There are technical problems, biomass power generation complex fuel supply system and boiler combustion technology, completely different from conventional thermal power units, biomass power generation main equipment - boiler body and other auxiliary machinery have achieved localization, but there are still problems in the biomass pretreatment and feeding system, the straw straw and other soft straw broken uneven serious. Often causes problems with the feeding system. And then directly affect the operation of biomass power plants. At present, the operating hours of the equipment are short, mainly due to the problems of the fuel handling feeding system (fuel quality factors are mostly) and the maturity of the combustion equipment is not high.

The development of biomass power generation projects in China is relatively late, and the technology is not perfect enough. How to choose feasible process flow according to different fuel components is related to the stable and reliable operation of the units after the completion of the project. In order to adapt to the situation that the same biomass boiler must burn a variety of straw, there is a problem of further technical transformation for the equipment imported from abroad.

(3) Policy issues, although existing laws and policies have provided a favorable environment for biomass power generation, these incentive policies and measures are not enough. The subsidies given by the government for the on-grid price of biomass power generation are based on desulfurization coal, and biomass fuel is different from coal, and the policy is unreasonable. Biomass plants no longer enjoy subsidies after 15 years of operation. And renewable power plants after 2010 enjoy a subsidy of 2% a year. In addition, because the Kyoto Protocol on greenhouse gases only provides for the emission reduction target by 2012, the CDM sales revenue of biomass power generation projects can only be included until 2012, affecting the efficiency.

3.2 Development prospect of biomass power generation

Due to the price disadvantage of biomass power generation and coal power, hydropower and so on, the lack of market competitiveness, the state adopts a price subsidy policy to support the development of biomass power generation. The feed-in price of biomass power plant is the benchmark feed-in price of desulfurization coal-fired units plus 0.25 yuan /kW · h subsidy price. Mixed-combustion power generation projects that consume more than 20% of the heat generated by conventional energy do not enjoy subsidized electricity prices. In addition, biomass power generation can enjoy a 10% income tax deduction, and straw biomass power generation can enjoy a VAT tax refund policy.