Effluent discharge/disposal

Microstrainers. Microstrainers are rotating steel screens with extremely fine stainless steel mesh (85—170 perforations per square centimeter (13—26/in. )). The flowing Hquid enters the open end of the dmm and passes through the mesh to the effluent end. The mesh traps soHd impurities and rotates with the dmm. A wash-water spray washes the trapped soHds into a hopper for final disposal. The mesh is washed with filtered effluent discharged from jets fitted into the dmm and then exposed to uv radiation to inhibit microbial growth. The mesh is washed with chlorine water at intervals of 7 to 28 days in order to control slime growth removal efficiencies are 30—55% of the appHed BOD and 40—60% of suspended soHds. 

Maintenance and operation of single-stage continuous powdered activated carbon system, 10 gal/min wet-oxidation unit, solid disposal, groundwater pumping, neutralization, and effluent discharge. 

Any waste water that cannot be recycled may be allowed to evaporate — a most economical method of disposal in a hot climate. In cooler climates, and particularly where industrial effluent discharge limits are extremely difficult to meet, evaporation... 

EXPOSURE ROUTES inhalation of vapors adsorption through the skin ingestion emissions and effluent discharges from manufacture, use, and application as an intermediate and pesticide emissions from combustion of chlorinated wastes ingestion of contaminated drinking water or fish people living near hazardous waste disposal sites... 

Methods of disposal being adapted, maximum limits of quantities of effluents which can be discharged after treatments, the concentrations of pollutants in the treated effluents, and disposal pathways for those effluents which cannot be treated by the industries are specified by statutory authorities in every country. 

The exhaust air of the disposal facility should be monitored in order to demonstrate compliance with the limits for airborne effluent discharges. Filters for the retention of aerosols may also be foreseen, depoiding on the specific conditions. Waste water arising fiom normal operation or as a consequence of an incident or a remedial action should be collected in order to allow a controlled discharge. 

The filter backwash discharge pond was placed In service In early 1983 following reconstruction of the 120-N-l percolation pond, which was formerly used for disposal of the backwash effluent. The pond Is fed via a 25- to 30-cm (10- to 12-1n.) burled line from the 183-N filtered water plant. Approximately 1,100,000 L/day (300,000 gal/day) of backwash effluent were disposed of at the unit. The 183-N filter backwash effluent has a neutral pH and contains low concentrations of several anions and cations (DOE-RL 1990). Aluminum sulfate (alum) Is used as a flocculent and polyacrylamide Is used as a filter ald/coagulant In filtered water production (DOE-RL 1990). Analysis of the filter backwash effluent Indicates that It does not contain any listed dangerous wastes or dangerous waste sources, or exhibit any dangerous waste characteristics or criteria per WAC 173-303 (DOE-RL 1990). Table 5-9 shows representative analyses of the filter backwash effluent. 

The obvious solution to water effluent limits and disposal cost is to avoid effluent production. Thus, the trend is to design plants with zero water effluent discharge (16), generally by adding water effluents to solid waste for dust or bulk density control. However, some plants also evaporate all the water effluents to form dry salts and minerals. 

The design should incorporate features that facilitate the safe handling, storage, transport and disposal of radioactive waste and the control of effluent discharges. 

Drainage from active mining areas is considerably less than from inactive mines because of the disposal methods currently employed. Prior to discharge, Hquid effluents are limed and settled to precipitate metals as hydroxides. Elocculants are used to reduce the total suspended soHds and, in some instances, filtration of thickener overflow is practiced. 

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