The positioning and development path of natural gas power generation in the energy transition period

Some scholars believe that the oxygen content in the flue gas of coal-fired units and gas units is very different, and the actual emission concentration is converted to the value under the same oxygen content, and the NOx emission concentration of gas units will be doubled, and the value will be higher than that of ultra-low emission coal-fired units. However, coal and natural gas are two completely different fuels, and the fuel itself and its combustion characteristics in the two generator sets determine its air excess coefficient and the oxygen content in the flue gas, so it is not practical to forcibly convert the emission concentration according to the unified oxygen content.

To comprehensively compare the cleanliness of the two forms of power generation, it should be compared according to the emissions of pollutants per unit of electricity. Because whether it is coal electricity or gas electricity, the end product is electricity. Therefore, it should be compared to the production of a unit of electricity, coal electricity and gas electricity emissions of how many pollutants; Rather than comparing the concentration of pollutants in the flue gas with the same oxygen content, which has no real meaning on the surface. It is obviously a more scientific and reasonable method to measure the cleanliness of coal power and gas power by the concentration of pollutants emitted by the production unit of electricity.

In addition to the above atmospheric emissions, coal flue gas emissions also contain certain radioactive substances and heavy metals. Although there is currently no unified measurement and measurement of these requirements and standards, but depending on the quality of coal, this part of the pollution may even cause very harmful consequences. In addition, coal-fired power generation will also produce a large amount of solid waste, including stone coal, fly ash, slag, desulfurization ash, desulfurization products, waste denitration catalyst, etc., and mercury, lead and other trace heavy metals are easy to enrich in the above solid waste, and improper disposal of solid waste is easy to cause secondary pollution.

Therefore, whether in terms of conventional air pollutant emissions or solid waste emissions, natural gas power generation is cleaner than coal-fired power generation, this conclusion is certain and has scientific basis.