Wastes containing high concentrations of toxic and combustible 

 contaminants such as water treatment sludges, storage tank "bottoms", 

 and separator sludges, require special collection and disposal methods. 

 Fluid bed incineration has replaced ocean dumping, deep well injection, 

 and evaporative lagoons as the preferred disposal technique for these 

 contaminated sludges. Sludge incineration reduces the volume of solid 

 waste matter because the residual particulate matter is collected from 

 the stack and disposed of in an approved landfill. 



Subproject: Industrial Wastewater Systems (SP-14 ) 



Disturbing Activity: Wastewater collection and treatment (design 

 and operation ) 



The chemical composition of wastewater varies according to the 

 processes employed by a particular refinery. The several million gallons 

 per day that may be used in processing comes in contact with various toxic 

 chemicals. An example of contaminated wastewater loads produced by a typi- 

 cal 100,000 B/D refinery is given in Table 15. 



A refinery usually has on-site wastewater treatment facilities. 

 Typical treatment of contaminated wastewaters would include the stripping 

 of sour water, co-mingling and treatment of spent caustics for organic 

 acid separation and neutralization of the water, and recycling of phenolic 

 waters to the desalter for phenol recovery. Wastewater that requires no 

 further treatment is called "clear stream water" and is ready for direct 

 release into receiving waters. Treatment systems must be designed to 

 function efficiently under continuous operation, since a malfunctioning 

 refinery treatment system can release a large amount of pollution in a 

 short time. 



Subproject: Industrial Cool ing Water Systems (SP-15) 



Disturbing Activity: Circulation of cooling water 



Of the total volume of water required daily by a refinery, roughly 

 80 to 05 percent is used for cooling. "Once-through" cooling systems 

 produce maximum heat discharge to the water (thermal pollution) and induce 

 maximum entrainment of marine organisms in the intake stream. Recircu- 

 lating cooling systems, employing cooling towers or ponds which release 

 the heat to the air rather than to the water, can be substituted. Recir- 

 culation, reuse, and release of heat to the air has a lesser cooling 

 water demand and produces less effluent. Anti-corrosion and fouling 

 chemicals, including chlorine and chromium, which are added to cooling 

 water to protect the tower and the condenser system, are highly toxic and 

 require proper collection and treatment. However, due to evaporative 

 losses, concentrations of dissolved substances and suspended particles 

 increase with each passage of water through the system. Refineries that 



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