The process of making energy from waste involves the conversion of discarded materials into fuel or electricity. There are many ways to accomplish this process. Gasification, Incineration, Landfill and methane capture are just a few of the options. You can also make use of your plastic waste. The end product, regardless of how it is made, is clean energy that's both renewable and sustainable.
Gasification
Gasification of waste energy is an environmentally sound and efficient way to convert waste energy. This process can produce up to 1,000 kilowatt-hours of electricity from one ton of municipal solid waste (MSW). It can also produce chemicals and methanol which are the base of many fertilizers. This process reduces landfill space requirements and reduces methane omissions.
One example of this is plasma gasification. It uses very high temperatures and oxygen-starved conditions to convert waste materials to simple compounds. It works in a similar way to pyrolysis except that it creates high-temperature Plasma gas. This process produces syngas, molten steel, and vitrified slate.
Incineration
Incineration of waste is a process that reduces the mass of waste and produces heat and flue gas. The ash, mostly composed of inorganic waste materials, is then recovered and the heat generated is used to generate electricity. The incineration process is often used to offset the costs of fossil fuels and landfills, and is an efficient way to produce renewable energy. Incineration can reduce the waste's mass by up 96%. It is however not a substitute for landfills.
Incinerators can be used to dispose of certain wastes that are not allowed in landfills. Incinerators can heat waste up to extremely high temperatures, which can kill pathogens and toxic substances. They are also ideal for treating wastewater from chemical multiproduct plants which produce a large amount of toxic material. These toxins are not compatible with conventional wastewater treatment facilities. A traditional method of disposing waste is to burn piles, or even pits. However, this method can lead to high levels of pollution.
Landfill methane capture
Landfill methane (or landfill gas) can be captured to make energy. It is formed when organic waste is broken down in landfills. The gas is mostly composed of methane and carbon dioxide with trace amounts of other gases. When captured, landfill methane can be used to produce energy and heat.
The process to capture methane from a landfill begins by capturing the methane during the anaerobic process. The landfill gas is then collected using perforated pipes that are placed in the capped landfill. The pipes are designed to allow the gases to rise to the surface in a vertical fashion without flowing laterally toward nearby buildings. The gases are then burned or vented into air. Once the methane has been captured, it is made into a renewable fuel and sold at a profit.
Plastic waste recycling
Recently, a new conversion process uses hydrothermal liquefaction with efficient separation to make energy from plastic waste. This technology can produce renewable fuels, and it can be used to make other chemicals. It could also be used for the production of specialty solvents or monomers. It could potentially meet up to 4% world fuel requirements. Next, the technology must be scaled up to greater scales.
RES Polyflow, a company that processes 100,000 tons of plastic per year, plans to convert the energy into diesel or naphtha which is used in the manufacture of polymers. The company already has a deal with BP to purchase the output from the plant. It is expected that the plant will open in 2011.
Agricultural waste conversion
Agricultural waste is a valuable resource and if properly converted, can be used to generate renewable energy sources such as biogas and bio-oil. It is expensive to collect, transport and store agricultural waste. Many countries still use traditional methods of disposal for this waste, which release harmful gases that pose a threat to the environment and human health. The energy conversion of agricultural waste can be a way for countries to manage waste and generate renewable energy.
Pretreatment can help to break down agricultural waste into different components. Microwave pyrolysis is a common method of thermochemical conversion, producing biochar, biooil and syngas. In developing countries, biomass residues don't get treated. Instead they are left to decompose or burned.