1.quantity,types of domestic solid waste 2.ecological problems caused by solid waste 3.utilization of radioactive waste 4.radioactive waste 5.type of pollution 6.wastewater energy systems 7.solid wastewater treatment technologies and products 8.Accumlated solid waste,composition,indication and density
** 1.what is emmision Pollution (including noise, heat, and radiation) discharged into the atmosphere by residential, commercial, and industrial facilities. Pollution discharged into water is called effluent. Automobile exhaust, or automobile emission, is a very large cause of air pollution in developed countries and urban areas and global warming.
Air pollutants are responsible for a number of adverse environmental effects, such as photochemical smog, acid rain, death of forests, or reduced atmospheric visibility. Emissions of greenhouse gases from combustion of fossil fuels are associated with the global warming of Earth’s climate. Certain air pollutants, including black carbon, not only contribute to global warming, but are also suspected of having immediate effect on regional climates.
The greenhouse effect is the increase in global temperatures which result from greenhouse gases trapping solar heat energy in the atmosphere. It is believed by many experts to be the primary cause of global warming. Greenhouse gases include substances, such as CO2, nitrous oxide, methane and carbon monoxide. Reducing the greenhouse effect can be achieved by taking steps to limit the emissions of greenhouse gases. Global warming caused by human-made greenhouse gas emissions threatens the world’s communities and ecosystems.
2.catalytic converters Three-Way Catalysts a 3-way catalytic converter (“catalyst”) is now standard on every gasoline-engined vehicle. The catalyst uses a ceramic or metallic core (known as a “substrate”) with a coating containing the precious metals, platinum, palladium and rhodium. These metals are the actual “Catalysts” that give the converter its name. Three-way catalysts operate in a closed-loop system with sensors to monitor the exhaust gas composition, linked to a computerised engine management system which continuously regulates the air to fuel ratio to maintain the necessary conditions for the catalyst to oxidise CO and HC to CO2 and water (H2O) while reducing NOx to nitrogen (N). For this process to work properly, the mixture of exhaust gases has to be perfectly balanced because the pollutants actually react with each other and with oxygen in the air, to achieve the required result. This perfect balance or “stoichiometric proportions” require a relatively “rich” fuel to air mixture, Diesel engines which use a much lower fuel to air ratio, and modern gasoline engines using “lean burn” technology to improve fuel economy and reduce CO2, need another way to deal with the problem.