Қалдықтан энергия алу процесі

Process of generating energy from the primary treatment of waste
energy wasted from a machine

Waste to energy (WtE) or energy from waste (EfW) is the process of generating energy in the form of electricity and/or heat from the primary treatment of waste, or the processing of waste into a fuel source. WtE is a form of energy recovery. Most WtE processes generate electricity and/or heat directly through combustion, or produce a combustible fuel commodity, such as methane, methanol, ethanol or synthetic fuels, often derived from the product syngas. The first US incinerator was built in 1885 on Governors Island in New York, New York. The first waste incinerator in Denmark was built in 1903 in Frederiksberg. The first facility in the Czech Republic was built in 1905 in Brno. Gasification and pyrolysis processes have been known and used for centuries and for coal as early as the 18th century Development technologies for processing [residual solid mixed waste] has only become a focus of attention in recent years stimulated by the search for more efficient energy recovery. (2004)

Incineration, the combustion of organic material such as waste with energy recovery, is the most common WtE implementation. All new WtE plants in OECD countries incinerating waste (residual MSW, commercial, industrial or RDF) must meet strict emission standards, including those on nitrogen oxides (NOx), sulphur dioxide (SO2), heavy metals and dioxins. Hence, modern incineration plants are vastly different from old types, some of which neither recovered energy nor materials. Modern incinerators reduce the volume of the original waste by 95 96 percent, depending upon composition and degree of recovery of materials such as metals from the ash for recycling. from modern incinerators. Other concerns include proper management of residues: toxic fly ash, which must be handled in hazardous waste disposal installation as well as incinerator bottom ash (IBA), which must be reused properly. Critics argue that incinerators destroy valuable resources and they may reduce incentives for recycling. Incinerators have electric efficiencies of 14 28%. According to the New York Times, modern incineration plants are so clean that "many times more dioxin is now released from home fireplaces and backyard barbecues than from incineration". According to the German Environmental Ministry, "because of stringent regulations, waste incineration plants are no longer significant in terms of emissions of dioxins, dust, and heavy metals". Compared with other waste to energy technologies, incineration seems to be the most attractive due to its higher power production efficiency, lower investment costs, and lower emission rates. Additionally, incineration yields the highest amount of electricity with the highest capacity to lessen pile of wastes in landfills through direct combustion.

One process that is used to convert plastic into fuel is pyrolysis, the thermal decomposition of materials at high temperatures in an inert atmosphere. It involves change of chemical composition and is mainly used for treatment of organic materials. In large scale production, plastic waste is ground and melted and then pyrolyzed. Catalytic converters help in the process. The vapours are condensed with oil or fuel and accumulated in settling tanks and filtered. Fuel is obtained after homogenation and can be used for automobiles and machinery. It is commonly termed as thermofuel or energy from plastic. A new process uses a two part catalyst, cobalt and zeolite, to convert plastics into propane. It works on polyethylene and polypropylene and the propane yield is approximately 80%.

MSW to a large extent is of biological origin (biogenic), e. g. paper, cardboard, wood, cloth, food scraps. Typically half of the energy content in MSW is from biogenic material. Consequently, this energy is often recognised as renewable energy according to the waste input. Several methods have been developed by the European CEN 343 working group to determine the biomass fraction of waste fuels, such as Refuse Derived Fuel/Solid Recovered Fuel. The initial two methods developed (CEN/TS 15440) were the manual sorting method and the selective dissolution method. A detailed systematic comparison of these two methods was published in 2010. Since each method suffered from limitations in properly characterizing the biomass fraction, two alternative methods have been developed. The first method uses the principles of radiocarbon dating. A technical review (CEN/TR 15591:2007) outlining the carbon 14 method was published in 2007. A technical standard of the carbon dating method (CEN/TS 15747:2008) is published in 2008. In the United States, there is already an equivalent carbon 14 method under the standard method ASTM D6866. The second method (so called balance method) employs existing data on materials composition and operating conditions of the WtE plant and calculates the most probable result based on a mathematical statistical model. Currently the balance method is installed at three Austrian and eight Danish incinerators. A comparison between both methods carried out at three full scale incinerators in Switzerland showed that both methods came to the same results. Carbon 14 dating can determine with precision the biomass fraction of waste, and also determine the biomass calorific value. Determining the calorific value is important for green certificate programs such as the Renewable Obligation Certificate program in the United Kingdom. These programs award certificates based on the energy produced from biomass. Several research papers, including the one commissioned by the Renewable Energy Association in the UK, have been published that demonstrate how the carbon 14 result can be used to calculate the biomass calorific value. The UK gas and electricity markets authority, Ofgem, released a statement in 2011 accepting the use of Carbon 14 as a way to determine the biomass energy content of waste feedstock under their administration of the Renewables Obligation. Their Fuel Measurement and Sampling (FMS) questionnaire describes the information they look for when considering such proposals.

A 2019 report commissioned by the Global Alliance for Incinerator Alternatives (GAIA), done by the Tishman Environment and Design Center at The New School, found that 79% of the then 73 operating waste to energy facilities in the U. S. are located in low income communities and/or "communities of color", because "of historic residential, racial segregation and expulsive zoning laws that allowed whiter, wealthier communities to exclude industrial uses and people of color from their boundaries." In Chester, Pennsylvania, where a community group is actively opposing their local waste to energy facility, Sintana Vergara, an assistant professor in the Department of Environmental Resources Engineering at Humboldt State University in California, commented that community resistance is based on both the pollution and the fact that many of these facilities have been sited in communities without any community input, and without any benefits to the community.

According to a 2019 United Nations Environment Programme report, there are 589 WtE plants in Europe and 82 in the United States. The following are some examples of WtE plants.

Renergi will scale up their system of converting waste organic materials into liquid fuels using a thermal treatment process in Collie, Western Australia. The system will process 1.5 tonnes of organic matter per hour. Annually the facility will divert 4000 tonnes of municipal waste from landfill and source an additional 8000 tonnes of organic waste from agricultural and forestry operations. Renergi’s patented “grinding pyrolysis” process aims to converts organic materials into biochar, bio gases and bio oil by applying heat in an environment with limited oxygen. Another project in the Rockingham Industrial Zone, roughly 45 kilometres south of Perth will see a 29 MW plant built with capacity to power 40,000 homes from an annual feedstock of 300,000 tonnes of municipal, industrial and commercial rubbish. As well as supplying electricity to the South West Interconnected System, 25 MW of the plant’s output has already been committed under a power purchase agreement.