The burning of coal as a source of fuel has adverse environmental effects that make the process of gasification desirable. The burning of coal release a gas called sulphur (IV) Oxide. When it is released in the atmosphere it reacts with oxygen to become sulphuric acid. There are adverse ecological damages when the acid is released to the environment as “acid rain” which is combination rainwater and the sulphuric acid. Acid rain destroys vegetation and the drainage pollutes the water sources which is an enormous ecological threat.
Coal mining poses a threat to miners because the extraction of the mineral is intrinsically harmful. It also presents health risks to miners due to the emission of coal dust and dangerous gases. The miners also ruin the surroundings due to the geological dislocation which is carried out in the extraction of the mineral.
During the combustion of coal, there is production of carbon (IV) oxide gas which is a greenhouse gas and majorly affects the environment through the greenhouse effect impacting the global climate negatively. Even though the emissions from coal plants can be refined to reduce the emissions gases such as sulphur (IV) oxide and nitrogen oxides, no procedure that has ever been designed to reduce emission of carbon (IV) oxide from the combustion of coal.
Fixed bed gasifier
The fixed bed gasifier is the earliest method of gasification that was developed using a countercurrent fixed bed gasifier. The bed is not actually fixed but it actually moves by gravity flow, as the burnt ash is withdrawn from the system. The steam and air are launched at the bottom and travel upward through the bed of coal. The coal is introduced at the top and travels downwards to counteract the gas flow. The flow of the hot gases up from the combustion zone preheats the coal which results to heat economy.