1. Why should we take treatment measures for gas turbine exhaust gas?
NOx in the exhaust gases of gas turbines is extremely harmful to the environment
1. Formation of photochemical smog: Nitrogen oxides (NOx) and hydrocarbons in the atmosphere undergo a series of photochemical reactions under sunlight to generate the notorious photochemical smog.
2. Formation of acid rain: NOx reacts with water molecules or other pollutants in the atmosphere to form acidic substances such as nitric acid or nitrate. Acid rain acidifies water bodies, causing aquatic life to die or mutate;Acid rain can leach and deplete soils, affecting crop growth and yieldsAcid rain can cause chemical reactions on the surfaces of buildings and artefacts, resulting in color fading or peeling, etc.
3. Destruction of the ozone layer: NOx continues to rise in the atmosphere, enters the stratosphere, and reacts with ozone in the stratosphere to produce nitric oxide and oxygen. This upsets the ozone balance in the stratosphere, reduces ozone concentrations, and leads to the depletion of the ozone layer.
4. Harm to human health: NO is easy to bind hemoglobin, and the body is hypoxic;NO2 mainly stimulates the human lungs and respiratory tract, and the corrosive damage of the body-building organs;
Damage to the ecological environment: NOx will cause acid rain, acid mist and photochemical smog, and promote global warming. In addition, the increase of nitrogen deposition will lead to eutrophication of surface water and acidification and poisonification of land, wetlands and groundwater systems, which will further cause damage to terrestrial and aquatic ecosystems.
2. Treatment technology of NOx in gas turbine exhaust gas - SCR selective catalytic reduction.
The principle of SCR denitrification technology: The principle of SCR (selective catalytic reduction) denitrification technology is to inject ammonia into the flue gas at a temperature of about 280 420 under the action of a catalyst to reduce NOx to N2 and H2O.
Market application of SCR denitrification technology: SCR denitrification technology has excellent properties such as high denitrification efficiency, stable operation and low ammonia escape, which can better meet the requirements of environmental protection and is widely used in thermal power plants, steel mills, cement plants, incineration plants and other industrial flue gas denitrification. According to statistics, in 2019, the application proportion of SCR denitrification technology in power, steel, coking and other industries has exceeded %.
System composition of SCR technology: The main components of SCR denitrification system include: catalyst reactor system, flue system, reducing agent ammonia storage system and reducing agent ammonia injection system.
Advantages of SCR technology: As a mature flue gas denitrification process, SCR technology has the advantages of high denitrification efficiency, low ammonia escape rate, low energy consumption and low operating costs.
3. Why SCR selective catalytic reduction technology is welcomed:
SCR technology has been widely used and recognized due to its advantages of high efficiency, low energy consumption, low operating costs and low ammonia escape rate. In addition, SCR technology can also effectively reduce NOx emissions, reduce environmental pollution, and conform to the global environmental protection trend, which is also one of the important reasons for its popularity.