Yesterday when I was driving my car, one question strike into my mind that what products are liberated from the tailpipe of my car. After reaching my home I did a small search onto the web and the outcomes of it I have mentioned below.
By reading this article you will get an idea about car exhaust and its constituents, its effects on animals and the environment, methods to control the exhaust emission, etc.
The chemicals comes out of a car like Carbon dioxide (CO2), carbon monoxide (CO), water vapors (H2O), oxygen (O2), Nitrogen monoxide (NO2), Nitrogen dioxide (NO2), Sulfur dioxide (SO2), hydrocarbons, particulate matter, etc.
What is a car exhaust?
The exhaust gases are the combustion products of IC engines expelled into the atmosphere. Normally it contains products like unburned hydrocarbons, sulfur and nitrogen oxides, carbon monoxide and carbon dioxide, water vapors, nitrogen, etc.
What chemical comes out of a car exhaust?
The oxidation or combustion of various automobile fuels (petrol, diesel, CNG, etc.) produces different products. We have listed some of the major constituents of the exhaust emission from the vehicles.
1] Carbon dioxide: More than 20 % of global CO2 generation is generated by the exhaust of transportation vehicles. It is one of the greenhouse gases responsible for global warming and also has an adverse effect on living organisms.
2] Carbon monoxide: Carbon monoxide is the product of an incomplete combustion process. It is mostly generated during the cold season when the engine takes more time to become warmer. Carbon monoxide is an odorless and tasteless gas that causes several health problems.
3] Water: The water vapor is also a product of the combustion process. In a running situation, it is expelled in the vapor form while after the engine is completely cooled, the condensed water droplets come out from the exhaust tailpipe.
4] Oxygen: An excess of oxygen that is not used for the combustion process is exhausted from the engine. In clean combustion, oxygen is present in very little proportion. If the engine rejects excess oxygen then it may be the indication of improper working of the oxygen sensor or your fuel injector is not working properly.
5] Nitrogen and nitrogen oxides: The Oxides of nitrogen are generally referred to as NOx emission that contains NO and NO2. These are generated at elevated temperatures due to the reaction between nitrogen and excess oxygen present inside the combustion chamber. These nitrogen oxides have adverse effects on human health.
6] Hydrocarbons: The exhaust of the engine also contains hydrocarbon molecules of unburned fuel or lubricants.
7] Sulfur dioxide: It is the product of the combustion process that arises due to the reaction of sulfur present in fuel with oxygen. It is also one of the air pollutants which have adverse effects on human health and the environment.
8] Particulate matter: These are the solid particles emitted from the exhaust of the engine after the complete combustion of the fuel. These particles also create trouble for respiration. This problem can be controlled by fitting a filter before the tailpipe.
Along with these major constituents the exhaust of the engine also contains various products.
What is the impact of exhaust gases on human health?
The exhaust contains various pollutants which can have adverse effects on human health. Every constituent of exhaust has the potential to affect different organs of the human body.
1] Carbon monoxide: After inhalation of carbon monoxide the molecules of carbon monoxide replace the oxygen from hemoglobin. Hence the oxygen is not supplied to the vital organs like the brain, heart, lungs, etc. Hence it may cause health issues like weakness, nausea, vomiting, chest pain, etc. The extreme inhalation of CO can cause death also.
2] Carbon dioxide: The high concentration of CO2 can cause clumsiness, rapid breathing, nausea, convulsions, etc. due to the deficiency of adequate amounts of oxygen.
3] Nitrogen Oxides: Nitrogen oxides cause respiratory diseases like asthma.
4] Sulfur dioxide: Sulfur dioxide also causes different respiratory diseases like pulmonary edema, Bronchospasm, pneumonitis, etc.
Along with these, the exhaust of vehicles can cause different health-related issues.
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What is the impact of exhaust gases on the environment?
The environment and ecosystem on the earth are also affected by exhaust emissions from vehicles. Some of the major effects of exhaust emission on the environment are,
1] Global warming: The exhaust of the engine contains greenhouse gases like carbon dioxide that helps to trap heat into the lower atmosphere of the earth.
2] Acid rain: The exhaust constituents like sulfur dioxide, nitrogen oxide are responsible for the phenomenon of acid rain.
3] Danger to animals: The different pollutants that arise from car exhaust can cause different diseases to the animals. Pollutants like benzene can cause cancer in animals.
4] Effect on crops: The pollutants present in exhaust gas also cause effects on crops and plant the like growth stimulation, premature leaf senescence, etc.
Along with this, the exhaust emission from vehicles has affected the environmental system in various ways.
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How to control exhaust gas emissions?
Various methods had been developed to control the emission of harmful products. Here we have listed some of the methods used to control the emissions.
1] Exhaust gas recirculation: The exhaust gas recirculation method helps to reduce the temperature of the engine hence the formation of sulfur dioxide and Nitrogen dioxide is prohibited.
2] Catalytic Converter: The catalytic converter helps for the complete oxidation of the unburnt exhaust gases. It converts harmful combustion products (Carbon monoxide, Nitrogen oxides, hydrocarbons, etc.) into non-polluting gases.
3] Air injection: This system is installed after the exhaust of the engine helps for the complete combustion of the hydrocarbons, carbon monoxide, unburned fuel, etc. Hence the harmful exhaust gases from the engine are converted into harmless gases.
Therefore the exhaust of automobiles contains various chemicals resulting from the process of combustion. Out of them, some constituents can cause harm to the health and environment. The modern technologies used in automobiles help to reduce or to convert harmful chemicals into harmless products.