Control liquid wastes

The most severe environmental problem of fruit and vegetable processors is the potential for water poUution if the liquid wastes are not handled properly. Cooking can cause odors, which are usually controlled by using furnaces as afterburners. 

Venmri scrubbers have been applied to control PM emissions from utility, industrial, commercial, and institutional boilers fired with coal, oil, wood, and liquid waste. They have also been applied to control emission sources in the chemical, mineral products, wood, pulp and paper, rock products, and asphalt manufacrnring industries lead, aluminum, iron and steel, and gray iron production industries and to municipal solid waste incinerators. Typically, venturi scrubbers are applied where it is necessary to obtain high collection efficiencies for fine PM. Thus, they are applicable to controlling emission sources with high concentrations of submicron PM. 

Tittlebaum, Marty E., Roger Seals, Frank Cartledge, Stephanie Engels, Louisiana State University. State of the Art on Stabilization of Hazardous Organic Liquid Wastes and Sludges. Critical Reviews in Environmental Control, Volume 15, Issue 2,1985. 

Laijava K, Laitinen T, Vahhnan T, Artmann S, Siemens V, Broekaert JAC, Klockow D. 1992. Measurements and control of mercury species in flue gases from liquid waste incineration. Int J Anal Chem 149 73-85. 

In the past, small quantities of liquid waste, in drums, has been disposed of by dumping at sea or in land-fill sites. This is not an environmentally acceptable method and is now subject to stringent controls. 

Large amounts of water are used in the copper concentration process, although disposal of liquid wastes is rarely a problem because the vast majority of the water is recycled back into the process. Once the wastewater exits the flotation process it is sent to a sediment control pond where it is held long enough for most of the sediment to settle. 

Recently the protection of the environment has become increasingly important for industry with the requirement that the potential impact on the environment is considered for all aspects of industrial processes. Such considerations are supported by environmental legislation that controls all types of emissions as well as the treatment of wastes. Such legislation is based on global standards that have largely resulted from developments within the European Union, Japan, and the United States in collaboration with international conventions. Of these, the Basel Convention (1989) and the Earth Summit in Rio de Janeiro (1992) were significant in the control and prevention of wastes. In the case of liquid wastes that are most appropriate for treatment by liquid liquid extraction, limits for discharge into the aqueous environment have been established by the three countries already mentioned. These limits depend on the particular country and sometimes on the industry. (See section 14.6.)... 

The description of the workings of the control technologies is beyond the scope of this article. However, it is worth noting that many of these technologies create substantial amounts of solid or liquid waste that needs to be disposed of properly. For example, in the USA the total amount of fly ash produced from coal combustion alone is about 57 Mt/y (Kalyoncu 2000). About one-third is utilized as secondary raw material (e.g., for aggregate and asphalt), but the rest is usually disposed of in landfills. The wet and dry scrubbers for S02 control produce a sludge or dry waste that finds little secondary use, and a large amount is disposed in landfills. 

Control Systems. Control systems are used to regulate the addition of liquid waste feed, auxiliary fuel, and combustion air flows to the incinerator furnace. In addition, scmbber operation is automated to help ensure meeting emission limits. Flows are measured using differential pressure... 

Generation of liquid waste from the uranium conversion process (see Table 5-1) is generally small and is handled by placing liquid effluent in lined ponds with sealed bottoms. The pond effluent is chemically neutralized to precipitate out uranium and uranium progeny in pond sludge. Water in the ponds is permitted to evaporate and sludge is disposed of as waste under controlled conditions (AEC 1974). 

Specific gravity of the liquid waste is measured, and the value is transmitted to a recorder which has an alarm in both the control house and main process building that activates at a specific gravity of 1.35. 

A simplified ventilation flow sketch (Figure 2) of the existing NFS high-level liquid waste storage facility shows the layout and relationship of the components. For both types of wastes a spare tank is available to transfer the existing waste in the event the operational tank should leak. The Purex neutralized HLW tank is operated at the boiling temperature by means of an immersion heater since the heat content of the currently stored waste is not sufficient to self boil. This is done to concentrate further the transferred slurries to the control limit of less than 8M sodium. 

The objective of the development reported here is to reduce tradional gas producer technology to commercial practice so that unattended biomass utilization systems under completely automatic control can be available to boiler operators now burning fluid fuels in packaged steam and heat generators. The system is to be designed for maximum gas production with minimum carbon remaining in the ash and zero liquid wastes production. 

Between 7 47 PM on Dec 2,2000 and 12 56 AM on Dec 3,2000, three spill-pillows (each containing approximately 20 pounds of liquid waste) were processed. How much of that was chemical agent VX is unknown. The spill-pillows contained talcum powder and an amorphous silicate absorbent. The 5X treated remains of the pillows, cardboard mines, fuses, and kicker chutes passed through the DFS and the non-combustible ash exited the heated discharge conveyor (HDC) to bin 135. At 8 06 AM on Dec 3, 2000 bin 135 was placed in the staging area (outside primary engineering control) with the lid open to cool. 

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