Sewer segregation

For example, a significant portion of refinery waste arises from oily sludge found in combined process/storm sewers. Segregation of the relatively clean rainwater runoff from the process streams can reduce the quantity of oily sludge generated. Furthermore, there is a much higher potential for recovery of oil from smaller, more concentrated process streams. 

B. Drainage System Upgrade Install above-grade, pressurized sewers, segregating stormwater and process water systems. 

If there is an existing plant, the choice must be made according to a given sewer segregation set up and existing treatment components that often include large API oil separator tanks. 

Move sewer and sewer gas adsorption system above-grade Segregate process water from rainwater Enclose or redesign API separator... 

The surface drainage areas, having been divided according to slope and drop in elevation, must now be segregated and run to the proper sewer classification. 

The complete segregation of all sewer systems at this point will represent nothing more than a one-line dis am layout for each system. Catch basins and manholes should now be added to the layouts. 

Any of these wastewaters may occur as either dilute rinse waters or concentrated baths. Except for the cyanide-bearing wastes, the wastewaters are generally connected to a common sewerage system for treatment and disposal. The cyanide wastes usually are collected in a segregated sewer system in order to prevent the release of toxic hydrogen cyanide gas under acidic ctHiditions. However, the cyanide wastes can be mixed with other waste streams provided that any acid streams are neutralized prior to mixing with the cyanide waste stream. 

Process Leaks Process leaks can occur with varying frequency. Instrumentation must be provided to monitor condensate quality to prevent damage to the boiler. Normal practice is to sewer condensate upon evidence of contamination until it is determined that the contamination is not severe enough to cause problems in the steam generation system. Procedures must be provided to identify and isolate causes of contamination rapidly. Provisions for segregating the system into small segments should be provided. 

A third sewer to segregate saline water if recycling is required. 

Sanitary sewer systems should be entirely segregated from oily water sewer systems. Similarly, process venting or blowdown systems should not be connected to the sewer system. 

---