Liquid wastes energy recovery from

The most suitable processes for the energy recovery from polyolefin wastes are (1) direct incineration, and (2) thermal and mechanical treatments. The latter procedures are applied for the production of gaseous, liquid, or solid fuels in a complex pyrolysis-gasification-incineration system. 

Heat Recovery Utilize thermal energy from exhaust gas stream (or liquid process stream) for process pre-heat Waste heat recovery Refinery nitrogen vaporizers Gas receiving expander turbine generator... 

Some relatively pure liquids recovered from the environment can be distilled or rereflned and reused. For example, petroleum products recovered from some waste sludge by thermal desorption or waste oils collected from automobiles can be rerefined to make a usable product. The potential to recover usable product from material spilled into the environment can be limited, however. Once spilled, a solvent or petroleum product begins to change physically and chemically. The liquid can become contaminated with water, dirt, or other substances. After some time, chemical and biochemical reactions will alter the chemical composition of the material. Further, the volume recovered from spill cleanup may be relatively small and a rereflning facility may not be located nearby. As a result, it may be more feasible simply to ship the waste for energy recovery. 

Petroleum wastes or other flammable liquid wastes are often burned for energy recovery. Relatively small amounts recovered from a spill can be shipped to a fuel blender, who mixes flammable waste liquids to achieve acceptable physical and chemical properties and markets the resulting material as fuel. Flammable wastes are sometimes burned at cement kilns for energy recovery because cement manufacture is highly energy-intensive. In the United States, facilities that recover energy from hazardous wastes are regulated under the RCRA Boiler and Industrial Furnace (BIF) Rules. 

Municipal solid waste (MS W) represents a significant resource for energy recovery operations. Energy from waste (EfW) conversion process is considered one of the most efficient commercially available technologies for the production of power, combined heat and power, and liquid biofuels via the Fischer—Tropsch reaction (Howes and Warren, 2013). 

All the heat used to supply heating in buildings (and much of that provided in any process) is ultimately lost from the building. Recovery of as much waste heat as possible reduces the need to purchase fresh energy from the suppliers. Much waste heat is produced in the form of contaminated hot moist air and in process liquids that require cooling. 

The last quadrant in Figure 16 shows the areas for eventual product diversification from energy and/or liquid biofuel vectors. Although these do not appear to offer great market potential they can address niche markets for the production of bio-chemicals and/or the recovery of the valuable products such as the monomer from waste polymers and aluminium from drink packaging. 

Gasification and pyrolysis are the thermal conversion processes available for the thermal treatment of solid wastes. As shown in Figure 8.3, different by-products are produced from the application of these processes and different energy and matter recovery systems can be used to treat these products [16, 27]. Both pyrolysis and gasification produce three different phases a solid phase (char, 5-25 wt%), liquid phase (tars, 10-45 wt%) and gas phase [14, 22, 28]. The main disadvantages of plastic pyrolysis and gasification are the necessity to control the chloride content in the feedstock and the risk of bad fluidisation because of particle agglomeration [29]. 

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