Knowledge of flue gas treatment for waste incineration power generation
Garbage incineration power generation refers to the work of using high-tech garbage incineration equipment to generate electricity in garbage incineration plants. However, the process of garbage incineration generates air pollution, which causes great harm to human health. Therefore, it is necessary to treat the air generated by garbage incineration technology. At present, the waste incineration power generation flue gas treatment technology is reliable, advanced, mature, and can provide the optimal flue gas treatment plan based on the treatment effect, achieving the goal of harmless to human health.
1. What are the other emission indicators of waste incineration power plants? Compared to international standards, at what level?
The biggest difference between domestic waste and foreign waste is that our waste is relatively wet. At present, the equipment is mature in technology, and the furnace temperature and flue gas emissions can be monitored in real time. That is to say, the data of various harmful emissions in the flue gas of incineration power plants can be seen by the Environmental Protection Bureau at all times, playing a supervisory role.
All emission indicators in the flue gas can meet the requirements of the Notice on Further Strengthening the Management of Environmental Impact Assessment for Biomass Power Generation Projects issued by the National Environmental Protection Commission [2008] No. 82. The main project indicators can meet the requirements of this standard and also meet the standards of the European Union, which is very low and will not have an impact on the environment.
The emission indicators of flue gas from incineration of garbage have reached the international level.
2. What are the main components of smoke generated after garbage incineration?
The main components of the flue gas after garbage incineration include dust, sulfur dioxide, carbon dioxide, nitrogen oxides, etc., as well as hydrogen fluoride, hydrogen chloride, furan, dioxins, etc. These harmful components will be treated and removed through advanced technological means, and the final emissions through the chimney are in accordance with the national environmental protection standard [2008] No. 82, with little impact on the environment.
3. Will the smoke emitted from the chimney be toxic?
After high-temperature combustion at temperatures ranging from 850 ℃ to 1100 ℃, some harmful gases can be decomposed, and then processed by a "semi dry method+activated carbon adsorption+bag dust removal" purification system. The harmful gases have been fully removed and can reach high standards. The dust (fly ash) adsorbed by harmful gases is treated as dangerous goods and strictly controlled. Finally, the gases discharged through the chimney are all up to standard, and the chimney height is generally 80 meters, Can be diffused in the atmosphere. Sometimes due to weather changes, white gas may be seen coming out of chimneys, which is just evaporated water vapor.
4. Will the chimney emit ash outside?
After high-performance special cloth bags are used to collect dust in the flue gas, there will be no floating ash phenomenon. Because the dust collection rate of bag dust removal can reach 99.99%, the dust is basically completely removed, so there will be no dust in the smoke discharged from the chimney. In addition, because it is not visible to the naked eye, there will be no floating ash phenomenon.
5. How to control the production of NOx (nitrogen oxides)?
The mechanism of NOx generation includes two aspects: firstly, the nitrogen content in garbage generates NOx during combustion, and secondly, the nitrogen content in the air oxidizes to produce NO2 at high temperatures. The most reasonable way to suppress NOx generation is to control the amount of NOx produced during combustion by limiting the amount of primary combustion air. Practice has proven that this is an effective method. Based on this principle, this project ensures that the NOx content (equivalent to NO2) in the flue gas is less than 400mg/Nm3 through furnace design and combustion control. Industry actual data shows that NOx control can be achieved through combustion control. The design reserves the location of SNCR (Denitration, i.e. removal of nitrogen oxides) device and spray inlet, which can greatly reduce NOx emissions and have no impact on the environment.