Air Pollution has become a global issue in the past decades, though it is evident that some areas have been more affected than others. In China, for example, air pollution causes up to 400,000 deaths every year. China's polluted environment is a cause of the rapid industrial and economic growth where coal remains the dominant energy source. As the economy keeps increasing, the energy consumption keeps rising. The major problem is that China has always put economic development ahead of the environment. China is the leader in sulphur and nitrogen oxide emissions, and second largest producer of greenhouse gases. They are finally starting to worry about this, and have been looking for techniques to solve this.
One of the apparatus China has been applying recently to try to reduce the air pollution is the electrostatic precipitator. It is an air cleaner that removes particles from gases; it works as an efficient filter and can remove things such as smoke and dust from the air stream. The electrostatic precipitators charges the particles by static electricity and then the particles are attracted to highly charged collector plates. These have been very useful for all the industrial area, where factories are often producing wastes.
A scientific technique frequently used in China with the means of converting nitrogen oxides into water is called selective catalytic reduction. It controls the nitrogen oxide emissions and reduces other emissions. Nitrogen oxide emissions are a smog causing pollutant and greenhouse gas. The process used to reduce nitrogen oxide emissions is efficient, reliable and safe. Diesel exhaust fluid and hot exhaust gases enter the catalytic converter. The catalytic converter contains a catalyst, which accelerates the chemical reaction. When the diesel exhaust fluid is injected into the hot exhaust stream and reaches the selective catalytic reduction catalyst, the ammonia created from urea reacts with nitrogen oxide to form water and nitrogen.
Selective Catalytic Reduction
Other techniques that are currently being used in China are increasing the fuel efficiency such as through the use of hybrid vehicles and the conversion to cleaner fuels (biodiesel). Science has been applied to all these methods in different way. Scientific investigations to create all these apparatuses were required. The electrostatic precipitator uses physics to work with the charged particles and static electricity. Scientific knowledge was applied here and thanks to that, air pollution has reduce in China. As well as in the selective catalytic reduction where basic chemistry was applied to figure out the decomposition of nitrogen oxide. Scientific skills where used to create and to build up these apparatus.
I believe it's been successful, but not completely; China is still at the top on the most polluted countries ranking. As I mentioned before this has to do with an economic force, well China has been growing up at a fast peas, especially regarding the industrial sector. Chinese people are now constructing factories within the cities, which is causing more sulphur and nitrogen oxide emissions. China has lost three quarter of their forestland in the past years and this environmental issue is causing people from the rural areas of China to go live near the river network, which generates water pollution. This has also become a social issue.