What Are Exhaust Emissions?
Exhaust gas emissions refer to the pollutants in the exhaust gas discharged from the chimney or the exhaust pipe opening. Is a serious pollution source of the atmospheric environment. Various exhaust gases emitted by industrial enterprises during combustion and production processes. Organic volatile substances in paints are also the main cause of air pollution, and the pollution in the coating process is much more serious than that of paint manufacturers. In the production of paint, the amount of solvent put into the atmosphere does not exceed 2% of the amount of solvent used in the manufacture of the paint, and the solvent volatilization during the ball mill production process is less than 0.25%. However, during the coating process, the losses vary from 20% to 80%, depending on the type of coating and the coating method. For example, in air spraying operations, 50% to 70% of solvent-based coatings are scattered by paint mist during the coating process, and all organic solvents are volatilized and released into the atmosphere. Hazardous exhaust gases emitted during coating are mainly concentrated in the spray paint production line. The spray booth, drying room, and drying room are the main sources of exhaust gas. [1]
- Industrial waste gas is an important part of air pollution and environmental pollution, and it is one of the main causes of haze weather in most areas of our country. Prior to 2007, industrial technological progress and industrial exhaust emissions showed a positive correlation but not significant, and environmental regulations had a significant inhibitory effect on industrial exhaust emissions. However, after 2007, industrial technology progress has a significant inhibitory effect on industrial exhaust emissions, and environmental regulations have a weaker degree of suppression of industrial exhaust emissions, which is related to China's energy conservation and emission reduction policies and the bias of industrial technology progress. In recent years, large
- During the production process of thermal power plant
- 1) Attach the sampling probe and sampling tube to the analyzer.
- (2) Warm up the vehicle under test.
- (3) Insert the sampling probe into the exhaust pipe, and the probe insertion depth should not be less than 300mm.
- (4) Maintain the engine from idle to medium speed for more than 5s, and then reduce to idle speed.
- (5) Set the meter to the highest range. After the pointer is stable, select the appropriate range and read the maximum value.
- (6) Withdraw the probe from the exhaust pipe, suck in fresh air, and turn off the power after 5min. [6]
- Carbon disulfide can be inhaled into the body through the respiratory tract and can also be ingested by the digestive tract. Carbon disulfide entering the body, a
Industrial emission control
- To prevent carbon disulfide pollution hazards, factories and enterprises that manufacture and use carbon disulfide should be located in urban suburbs or residential areas with small populations. The distance between the factory and the residential area should be at least 1km, and it should be built on the upwind side of the area with the smallest annual wind direction and downstream of the local water source.
- Process reforms and technological innovations should be carried out in factories. Reduce the amount of carbon disulfide and prevent running, dripping, dripping and leaking to protect workers' health and reduce fugitive emissions. After collecting the carbon disulfide-containing exhaust gas, it should be discharged through a high chimney. It should be recycled before being discharged, such as using a condenser to condense carbon disulfide into a liquid for recovery. Activated carbon can also be placed in the ventilation pipe or exhaust pipe to absorb carbon disulfide.
- Carbon disulfide in wastewater can be purified by neutralization method, coagulation sedimentation method and biological filter method before being discharged. [3]
Exhaust gas policy constraints
- In order to prevent the pollution of automobile and motorcycle exhaust to the atmospheric environment, the State Environmental Protection Administration and the State Technical Supervision Bureau have approved the following relevant standards.
- GB 1462193 Motorcycle Exhaust Pollutant Emission Standard
- GB 14761.293 emission standards for exhaust pollutants from gasoline engines
- GB 14761.393 Emission Standards for Evaporative Pollutants from Gasoline Vehicle Fuel
- GB 14761.493 Pollutant emission standard for automobile crankcase
- GB 14761.593 Emission Standard of Pollutants for Gasoline Vehicles at Idle Speed
- GB 14761.693 Free acceleration smoke emission standard for diesel vehicles
- GB 14761.793 full load smoke emission standard for automotive diesel engines
- This type of emission standard mainly provides corresponding restrictions on carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO x ) and smoke in the exhaust gas. Each emission standard has a corresponding measurement method. The standards are uniformly supervised and implemented by the environmental protection administrative departments at all levels. [7]
Exhaust emission technology prevention
- Possible ways to reduce the pollution of automobile exhaust emissions The reduction of automobile pollution to the atmospheric environment can be started from the following two aspects. (1) Reducing the emissions of pollution sources Reducing the emissions of pollution sources is to reduce the emission of automobile exhaust gas, which involves: a. Automobile technology. In addition to engine technology, it also involves the optimization and matching of automotive powertrains and vehicle technology; b. Planning and design of traffic roads. Reasonably plan roads, ensure good traffic conditions and sparse traffic density, reduce the running time of the car engine at idle speed and low load, and thus reduce car exhaust emissions; c. Car driving conditions. When the car is operating under variable conditions (acceleration, deceleration, idling) and under relatively poor emission performance, its emissions will increase significantly. d. Repair and maintenance. Repair and maintenance of in-use vehicles is one of the important measures to ensure low pollution of automobiles. Technical Measures to Reduce Gasoline Vehicle Exhaust Emissions There is still a certain gap between domestic automobile exhaust emission quality and the world's advanced low emission vehicles. If you rely on your own technical strength, it will be difficult to reduce this gap in a short time. Independent development is needed, because one technical measure cannot be suitable for various models, and a large number of matching test studies are needed for different models. This requires relevant departments to formulate overall and sustainable plans to reduce automobile exhaust emissions. From the perspective of reducing automobile exhaust emissions, according to long-term research results at home and abroad, it is possible to reduce emissions using different technical measures. But it will also increase the complexity of the system and affect other performance. Therefore, various performance indicators must be taken into account. Reducing automobile exhaust emissions is not only related to engine performance, but also closely related to the matching of automobile powertrain and optimization of vehicle parameters. In addition, it is necessary to formulate a reasonable technical route and research and development strategy according to the technical conditions at the time and the restrictions of automobile exhaust emission regulations. The technical circuit for reducing automobile exhaust emissions starts from the following three aspects: camshaft adjustment system; mixture formation measures; control strategies for gasoline engines. [8]