In recent years, due to the requirement of environmental protection, coal-fired boilers have gradually required oxygen-enriched or pure oxygen combustion. When using air to burn, 78% of nitrogen does not work in combustion support. At high temperature, it will produce NOX pollutants with oxygen and take away a lot of heat energy before leaving. If pure oxygen is used to burn, the content of nitrogen and oxygen compounds can be greatly reduced, and the concentration of carbon dioxide in the emission can also be increased, which can be captured and recycled, and the emission of carbon dioxide can be greatly reduced. The air separation plant will make great contributions to environmental protection in the use of coal in the future. Among them, IGCC is also called green coal power, which is the development direction of power plants in the future. How to make good use of this development opportunity is a problem that we empty separation personnel need to think about.
In 1972, the world's first IGCC power station, which was based on the gas-steam combined cycle of pressurized boiler, was put into operation at the stilch power station in Lunen, Germany. The demonstration project was aborted because it could not maintain stable operation for a long time.
IGCC, which is recognized in the world as the real successful trial run, was built in May 1984 in Daggett, California, America as the "Cool water" power station. The successful demonstration operation of "Cold Water" power station announced such a fact and direction to the world that IGCC is a promising clean coal power generation technology, it has completely solved the chronic disease of serious pollution and emission of coal-fired power stations. It is likely to be the most promising way of coal-fired power generation in the 21st century, except for the proliferation reactor.
According to the technological process diagram of 2 × 400 mw igcc project in Langfang of China Power Investment Corporation, the process of IGCC can be roughly understood. The whole process is coal and oxygen gasification, and it enters into gas turbine to generate electricity through purification. The waste heat of gas turbine is then generated by waste heat boiler. Such a 400 MW unit needs to be equipped with 86000 air separation plant. Therefore, IGCC has a great demand for air separation in the future.
For IGCC project, the current new environmental protection standard requires that the air pollutants emission of IGCC power station should be implemented according to the gas turbine power station, while the electricity price should be implemented according to the coal electricity standard. However, the power generation economy achieved by IGCC at present is not as good as that of coal-fired power plants with the supercritical parameters of FGD. IGCC for the purpose of pure power generation develops relatively slowly. Moreover, the large air separation attached to IGCC is monopolized by Hangyang Air Supply Co., Ltd. and foreign large companies, and the price is relatively high, which increases the investment cost of IGCC. As a result, IGCC has a great voice, but seldom goes to projects.
As for the future of IGCC, I am optimistic about it in general, and can combine power generation technology with chemical technology to form a multi-generation energy system with gas as the core. In the future, IGCC can improve various products, such as compressed air, liquid oxygen, liquid nitrogen, liquid argon, hydrogen, sulfur, carbon dioxide, heating steam and so on, to increase the economic efficiency of IGCC. I hope that our country can give better policies such as IGCC electricity price as the electricity price of gas power plant. At present, all countries have not implemented the reduction of carbon dioxide emissions as a verbal matter. If environmental protection strictly requires the recovery of carbon dioxide, IGCC will have more good news.
Of course, what we focus on is that the development of IGCC can bring a spring to the space separation! Strive to produce more energy-saving air separation equipment to support IGCC.
