Concept of Co-processing
Co-processing is a proven sustainable development concept that reduces demands on natural resources, reduces pollution and landfill space, thus contributing to reducing the environmental footprint. Co-processing is also based on the principles of industrial ecology, which considers the best features of the flow of information, materials, and energy of biological ecosystems, with the aim of improving the exchange of these essential resources in the industrial world.
Figure 1: Types of Co-processing
In summary, the benefits of Co-processing are:
- to conserve natural (non-renewable) resources of energy and materials,
- to reduce emissions of greenhouse gases in order to slow global warming and demonstrate a positive impact on integrated environmental indicators, such as the ecological footprint,
- to reduce the environmental impacts of the extraction (mining or quarrying), transporting, and processing of raw materials,
- to reduce dependence on primary resource markets,
- to save landfill space and reduce the pollution caused by the disposal of waste, and
- to destroy waste eliminating potential future liabilities.
Co-processing contributes to the industrial competitiveness, is a complementary technology to concepts such as cleaner production or recycling and should be considered as a treatment alternative within an integrated waste management concept. Some EII offer co-processing as a sustainable waste management service. It is usually more cost effective to adapt existing facilities of EII than building new waste treatment capacities thereby reducing waste management cost to society.
The waste management hierarchy (see figure below) shows that Co-processing is a recovery activity which should be considered after waste prevention and recycling; Co-processing ranks higher in this hierarchy in comparison to disposal activities such as landfilling or incineration.
Figure 2: Waste Management Hierarchy
Potential of Co-processing
The global industrial demand for energy is roughly 45% of the total demand and the requirements of the energy intensive industries (EII) are more than half of the total industrial demand, at 27%.
Worldwide, wastes suitable for Co-processing have an energy potential equivalent to nearly 20% of the fossil fuel energy used by the EII and coal-fired power plants. By 2030, the thermal substitution rate of waste could rise to nearly 30%. In the EU-25 countries of Europe, the available energy potential in waste currently represents nearly 40% of this demand, and this is expected to rise to almost 50% by 2030.
The EU cement industry already uses more than 40% fuels derived from waste and biomass in supplying the thermal energy to the grey clinker making process. Although the choice for this so-called alternative fuels (AF) is typically cost driven, other factors are becoming more important. Use of AF provides benefits for both society and the company: CO2-emissions are lower than with fossil fuels, waste can be co-processed in an efficient and sustainable manner and the demand for certain virgin materials can be reduced. Yet there are large differences in the share of AF used between the European Union (EU) member states. Clearly, the societal benefits can be enlarged if more member states increase their AF share. In this study Ecofys assess the barriers and opportunities for further uptake of AF in 14 EU member states. Ecofys found that local factors constrain the market potential to a much larger extent than the technical and economic feasibility of the cement industry itself. In this summary they present the overall findings. The detailed assessments are available in separate cases studies.Source
Roughly 60% of the waste that could be used for Co-processing is biomass and therefore carbon neutral. In this way Co-processing offers a significant potential for the reduction of greenhouse gas emissions from fossil fuels. Furthermore, diverting industrial waste streams from landfills and incinerators without energy recovery contributes to reducing overall CO2 emissions when used to substitute fossil fuels through Co-processing (as illustrated in the figure below).
Figure 3: Reduction of Emissions through Co-processing
Other factors that must be considered when Co-processing waste include product quality standards, permitting aspects, and transparent communication in order to gain public acceptance.
A cement is a binder, a chemical substance used for construction that sets, hardens, and adheres to other materials to bind them together. Cement is seldom used on its own, but rather to bind sand and gravel (aggregate) together. Cement mixed with fine aggregate produces mortar for masonry, or with sand and gravel, produces concrete. Concrete is the most widely used material in existence and is behind only water as the planet's most-consumed resource.
Biogas is a gaseous renewable energy source produced from raw materials such as agricultural waste, manure, municipal waste, plant material, sewage, green waste, wastewater, and food waste. Biogas is produced by anaerobic digestion with anaerobic organisms or methanogens inside an anaerobic digester, biodigester or a bioreactor. The gas composition is primarily methane and carbon dioxide and may have small amounts of hydrogen sulfide, moisture and siloxanes. The gases methane and hydrogen, can be combusted or oxidized with oxygen. This energy release allows biogas to be used as a fuel; it can be used in fuel cells and for heating purpose, such as in cooking. It can also be used in a gas engine to convert the energy in the gas into electricity and heat.
Waste management or waste disposal includes the processes and actions required to manage waste from its inception to its final disposal. This includes the collection, transport, treatment, and disposal of waste, together with monitoring and regulation of the waste management process and waste-related laws, technologies, and economic mechanisms.
Incineration is a waste treatment process that involves the combustion of substances contained in waste materials. Industrial plants for waste incineration are commonly referred to as waste-to-energy facilities. Incineration and other high-temperature waste treatment systems are described as "thermal treatment". Incineration of waste materials converts the waste into ash, flue gas and heat. The ash is mostly formed by the inorganic constituents of the waste and may take the form of solid lumps or particulates carried by the flue gas. The flue gases must be cleaned of gaseous and particulate pollutants before they are dispersed into the atmosphere. In some cases, the heat that is generated by incineration can be used to generate electric power.
Electric power systems consist of generation plants of different energy sources, transmission networks, and distribution lines. Each of these components can have environmental impacts at multiple stages of their development and use including in their construction, during the generation of electricity, and in their decommissioning and disposal. These impacts can be split into operational impacts and construction impacts. All forms of electricity generation have some form of environmental impact, but coal-fired power is the dirtiest. This page is organized by energy source and includes impacts such as water usage, emissions, local pollution, and wildlife displacement.
A waste-to-energy plant is a waste management facility that combusts wastes to produce electricity. This type of power plant is sometimes called a trash-to-energy, municipal waste incineration, energy recovery, or resource recovery plant.
Glass recycling is the processing of waste glass into usable products. Glass that is crushed or imploded and ready to be remelted is called cullet. There are two types of cullet: internal and external. Internal cullet is composed of defective products detected and rejected by a quality control process during the industrial process of glass manufacturing, transition phases of product changes and production offcuts. External cullet is waste glass that has been collected or reprocessed with the purpose of recycling. External cullet is classified as waste. The word "cullet", when used in the context of end-of-waste, will always refer to external cullet.
Refuse-derived fuel (RDF) is a fuel produced from various types of waste such as municipal solid waste (MSW), industrial waste or commercial waste.
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.
Renewable Fuels are fuels produced from renewable resources. Examples include: biofuels, Hydrogen fuel, and fully synthetic fuel produced from ambient carbon dioxide and water. This is in contrast to non-renewable fuels such as natural gas, LPG (propane), petroleum and other fossil fuels and nuclear energy. Renewable fuels can include fuels that are synthesized from renewable energy sources, such as wind and solar. Renewable fuels have gained in popularity due to their sustainability, low contributions to the carbon cycle, and in some cases lower amounts of greenhouse gases. The geo-political ramifications of these fuels are also of interest, particularly to industrialized economies which desire independence from Middle Eastern oil.
Biomass, in the context of energy production, is matter from recently living organisms which is used for bioenergy production. Examples include wood, wood residues, energy crops, agricultural residues including straw, and organic waste from industry and households. Wood and wood residues is the largest biomass energy source today. Wood can be used as a fuel directly or processed into pellet fuel or other forms of fuels. Other plants can also be used as fuel, for instance maize, switchgrass, miscanthus and bamboo. The main waste feedstocks are wood waste, agricultural waste, municipal solid waste, and manufacturing waste. Upgrading raw biomass to higher grade fuels can be achieved by different methods, broadly classified as thermal, chemical, or biochemical.
This is a glossary of environmental science.
Tire-derived fuel (TDF) is composed of shredded scrap tires. Tires may be mixed with coal or other fuels, such as wood or chemical wastes, to be burned in concrete kilns, power plants, or paper mills. An EPA test program concluded that, with the exception of zinc emissions, potential emissions from TDF are not expected to be very much different from other conventional fossil fuels, as long as combustion occurs in a well-designed, well-operated and well-maintained combustion device.
Waste are unwanted or unusable materials. Waste is any substance discarded after primary use, or is worthless, defective and of no use. A by-product, by contrast is a joint product of relatively minor economic value. A waste product may become a by-product, joint product or resource through an invention that raises a waste product's value above zero.
The environmental effects of paper are significant, which has led to changes in industry and behaviour at both business and personal levels. With the use of modern technology such as the printing press and the highly mechanized harvesting of wood, disposable paper became a relatively cheap commodity, which led to a high level of consumption and waste. The rise in global environmental issues such as air and water pollution, climate change, overflowing landfills and clearcutting have all lead to increased government regulations. There is now a trend towards sustainability in the pulp and paper industry as it moves to reduce clear cutting, water use, greenhouse gas emissions, fossil fuel consumption and clean up its influence on local water supplies and air pollution.
The environmental impact of the energy industry is significant, as energy and natural resource consumption are closely related. Producing, transporting, or consuming energy all have an environmental impact. Energy has been harnessed by human beings for millennia. Initially it was with the use of fire for light, heat, cooking and for safety, and its use can be traced back at least 1.9 million years. In recent years there has been a trend towards the increased commercialization of various renewable energy sources. Scientific consensus on some of the main human activities that contribute to global warming are considered to be increasing concentrations of greenhouse gases, causing a warming effect, global changes to land surface, such as deforestation, for a warming effect, increasing concentrations of aerosols, mainly for a cooling effect.
The United States Environmental Protection Agency (EPA) was established in July 1970 when the White House and the United States Congress came together due to the public's demand for cleaner natural resources. The purpose of the EPA is to repair the damage done to the environment and to set up new criteria to allow Americans to make a clean environment a reality. The ultimate goal of the EPA is to protect human health and the environment.
Landfill gas utilization is a process of gathering, processing, and treating the methane or another gas emitted from decomposing garbage to produce electricity, heat, fuels, and various chemical compounds. After fossil fuel and agriculture, landfill gas is the third largest human generated source of methane. Compared to CO2, methane is 25 times more effective as a greenhouse gas. It is important not only to control its emission but, where conditions allow, use it to generate energy, thus offsetting the contribution of two major sources of greenhouse gases towards climate change. The number of landfill gas projects, which convert the gas into power, went from 399 in 2005 to 519 in 2009 in the United States, according to the US Environmental Protection Agency. These projects are popular because they control energy costs and reduce greenhouse gas emissions. These projects collect the methane gas and treat it, so it can be used for electricity or upgraded to pipeline-grade gas. These projects power homes, buildings, and vehicles.
The environmental impact of concrete, its manufacture, and its applications, are complex, driven in part by direct impacts of construction and infrastructure, as well as by CO2 emissions; between 4-8% of total global CO2 emissions come from concrete. Many depend on circumstances. A major component is cement, which has its own environmental and social impacts and contributes largely to those of concrete.
Digital ecology is a science about the interdependence of digital systems and the natural environment. This field of study looks at the methods in which digital technologies are changing the way how people interact with the environment, as well as how these technologies affects the environment itself. It is a branch of ecology that promotes green practices to fight digital pollution. Currently the total carbon footprint of the internet, our electronic devices, and supporting elements accounts for about 3.7% of global greenhouse gas emissions.
