How does a Gasifier work?
Waste Gasification Process
Gasification is a process of conversion of solid Hydrocarbon (HC) fuels into a mixture of combustible gas like producer gas. It is one of the best solutions for handling wastes. However, it is a complex process and requires tremendous effort.
It also requires innovative ideas to successfully process the enormous amount of waste. After successful development of this process, it easily transforms the usable hydrogen and carbon compound to producer gas. This leaves all the undesirable solid components along with some fixed proportion of carbon at the end. This ensures that waste is properly disposed of after being segregated, after which usable energy is recovered.
Some hydrocarboneous fuels like coal, wood, manure, waste and such residues are converted into gas form. A Gasifier is a chemical reactor where the process of conversion of these fuels takes place. This process involves sub-processes for the further break down of solid fuels into producer gases.
The waste gasification processes are:
- Drying
This is the initial process where the drying of fuel takes place. This takes place in the uppermost portion of the reactor. The moisture comes out from the feed in the form of vapour.
- Pyrolysis
This process involves the chemical decomposition of the organic substances. These substances are heated at a temperature above 200 degrees in the absence of oxygen. Thus, reduction occurs. The by-products are char and volatiles.
- Combustion
This process includes the supply of controlled oxygen to the fuel. Thus, oxidation takes place and heat is released.
- Reduction
The combustion products like Water vapour(H2O) and Carbon dioxide(CO2) undergo the process of the reduction under high temperature to produce Carbon Monoxide(CO) and Hydrogen(H2).
Due to constant rise with the urbanization, the world is facing major challenges like waste generation, collection and processing. There are some technologies that can promote sustainable waste management.
Importance of Waste Management
Several industries generate heaps of solid and liquid waste as a by-product. This is then thrown into the water bodies or released through chimneys in the air. These wastes are released without any sort of treatment. This purely consists of harmful gases like Methane(CH4) and Carbon Dioxide(CO2). Due to this, there is a release of harmful greenhouse gases causing depletion of the ozone layer. This also pollutes the air and water in every way.
However, these situations can be brought under control with the technologies that promote environment-friendly conversion of waste to energy including organized treatment of wastes before disposing them off and release of minimal amount of waste, contributing to sustainable energy.
Waste to energy (WTE) conversion technologies
Here are some of the most popular waste to energy conversion technologies and their impact.
These technologies for the wastes make use of extensive combustion with the emission of heat and power.
Through Biochemical and thermochemical conversion, energy can be recovered from the organic waste.
- The thermochemical conversion processes are capable of treating the wastes that contain high organic substances. Also, these processes can treat non-biodegradable waste which contains negligible moisture content. Gasification and Incineration are certain options that promote waste to energy.
- Biochemical conversion processes are the most suitable for wastes that contain a high amount of water content or moisture and organic biodegradable matter. One of the popular methods for this is Anaerobic Digestion.
Waste to Energy (WTE) can recover latent energy which is present in the solid or liquid wastes. This offers a renewable source of energy for a sustainable environment. These consist of waste processing and treatment methods.
- Here the total quantity of waste gets lowered. However, it depends on the waste composition and technology used for waste processing and treatment.
- Also, this reduces the demand for the free lands which are used for dumping and landfilling of waste.
- This process stops environmental degradation.
- It reduces the demand and cost of transportation that might be involved in carrying the waste to dumping landfills.
- The process also aids in reducing the pollution of land, water ,and air.
- This promotes power and energy generation and consumption.
Along with this, the by-products from such processes can deliver efficient fertilizers and aid the growth of agriculture and related industries.
The landfill waste can also be utilized in many ways. After some time, the waste in such dump lands or landfills get converted into gases. Later, this can be utilized through energy conversion systems, delivering energy that works as an alternative to natural gas, steam, thermal electricity, coal and the like.
