Reuse incinerator waste

NEUTREC A flue-gas desulfurization process, intended for treating the waste gases from incinerators for municipal, hospital, and industrial wastes. Sodium bicarbonate, optionally mixed with active carbon, is injected into the gases after the usual bag filter, and the solid products are removed in a second bag filter. Sodium compounds can be recovered from the product for reuse, and ary toxic compounds disposed of separately. Developed by Solvay and operated in Europe since 1991. 

One of the four plants presently treats and reuses 75% of its waste stream as vent scrubber washwater. A second plant incinerates formulating/packaging process waste and discharges incinerator blowdown that contains levels of pesticides measured as not detected. 

Off-site waste disposal methods involve the transfer of solvent wastes to an alternative location before their treatment, reuse, or release into the environment. One such method commonly used both on- and offsite is incineration. Solvent wastes are often incinerated, especially when they contain toxic substances and pose long-term EHS risks if directly released. The process of waste incineration releases a large amount of CO2 into the environment, but often the heat generated from this process may be recovered for use within a plant. When contaminated... 

The need to design inherently safer plants has been expanded to encompass designing evironmentally acceptable plants. Environmentally acceptable plants generate minimum quantities of potentially hazardous wastes either as potential emissions to the environment or as materials requiring disposal. Wastes are recycled and reused where possible. If this is not possible, they may be treated to reduce or eliminate the hazard or destroyed through incineration. Disposal in a secure landfill is the final option. 

To deal with the hazardous status of ashes from CCA-treated wood, the arsenic must either be extracted or the ashes would need to be encapsulated through solidification/stabilization. Hypothetically, the recovery and reuse of arsenic from the incineration of CCA-treated wood could reduce arsenic mining and imports. However, arsenic use has declined in recent years (Chapter 5) and there is little economic incentive to incinerate solid wastes and recover any volatile arsenic (Leist, Casey and Caridi, 2000, 126, 127). 

Waste quantities can be recovered for reuse by distillation. Otherwise, place in a solvent disposal container for disposal by burning in a chemical incinerator equipped with afterburner and scrubber.6,8... 

When the solvent content of the wastewater is high, incineration may be the lowest cost option for disposal. However, VOCs are often stripped for reuse or separate incineration. Soluble salts such as of widely used metals (iron, aluminum, and chromium) and of commonly used anions (cyanide and fluoride) can pose waste disposal problems. Excessive levels of such algal bloom promoters as ammonia and phosphate introduce effluent problems on a large scale. 

In most bioseparations, a waste stream will be generated which has no commercial value. Depending on the nature of this waste stream, it may not be possible to dispose of the material easily without further processing. For example, solvent-rich mother filtrates in antibiotics production are usually distilled to separate the solvent and aqueous phases so that the aqueous phase composition is acceptable for discharge to the sewer and the solvent phase can be reused or incinerated as a smaller volume of material. 

Rotary kiln incineration at a temperature range of 820-1,000 °C and residence times of seconds for liquid and gaseous wastes and hours for solids can totally destroy dinitrocresols. Fluidized bed incineration at a temperature range of 450-980 °C and residence times of seconds for liquid and gaseous wastes and longer for solid wastes can also destroy dinitrocresols. Mixing dinitrocresols with a more flammable solvent may facilitate incineration. Containers used for dinitrocresols that are not to be reused can be disposed by burial in a designated landfill (HSDB 1994). 

New waste treatment facilities allow all waste to be reused without the need for sorting it into waste to be recycled and waste to be incinerated or put in a landfill, but the proposed plan does not involve these new facilities. 

Fischer and co-workers undertook a LCA of the 26 organic solvents which they had already assessed in terms of EHS criteria (see above).They used the Eco-solvent software tool (http //www.sust-chem.ethz.ch/tools/ecosolvent/), which on the basis of industrial data considers the birth of the solvent (its petrochemical production) and its death by either a distillation process or treatment in a hazardous waste incineration plant. For both types of end-of-life treatment, environmental credits were granted where appropriate, e.g. solvent recovery and reuse upon distillation. The results of this assessment are shown in Figure 1.2. From an LCA perspective, tetrahydrofuran (THF), butyl acetate, cyclohexanone and 1-propanol are not good solvents. This is primarily due to the environmental... 

PAC is widely used in industry to remove undesired organic constituents, and has been used by many water purification plants. The residue is a wet, organic-loaded, carbon waste. In the past, these wastes were disposed into streams, incinerated, or buried. Recently, new developments seem to have overcome the problem of large quantity of carbon dust. Several systems show promise in reusing the powdered carbon and will be briefly discussed. 

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