What I need to know
The water that is condensed from air produced by lubricated air compressors contain oil and other contaminates. This condensate cannot be discharged outside or in a storm sewer system and meet EPA standards.
The cost of collecting this condensate, hauling it off and having it properly disposed of is quite expensive. There are several alternatives some which are high risk options.
The first is to drain it to the sanitary sewer system for sewage plant treatment. Sanitary sewage systems have limits on how much oil can be in your effluent. These limits vary widely from locale to locale. Exceeding these limits can result in large fines and in extreme cases plant closures. These limits usually are based on density of the oil. Most compressed air systems will release the same amount of oil per CFM of air compressed. During high humidity warm periods there is lots of water condensed to dilute the effluent and it may meet local requirements. However during colder less humid periods, less dilution occurs and the effluent may exceed standards. In addition, poor maintenance or compressor malfunction can raise the amount of oil well above the limits. Some air compressor oils are biodegradable when in condensate. However, since most effluent has many sources for oil or grease, an expensive chemical analysis to determine what oil is in the effluent would be needed to avoid being fined if authority limits are exceeded.
Another option is to collect the condensate and use equipment to separate most of the oil which reduces the disposal cost because the volume is daftly reduced. The most common type of this equipment uses a combination of gravity separation (oil is lighter than water) and activated charcoal as a final filter which requires periodic replacement as it fills with oil. Another type of equipment utilizes materials in a container that adsorbs the oil and allows the water to pass through. Once the adsorbing material is saturated, the unit is replaced and the spent unit is disposed of. The proper sizing of this type of equipment requires knowledge of the compressor oil being used, local limits, and type of air compressor. Changing oil after the condensate management equipment is installed can lead to failure to make local limits. Please note that there is still some oil in the water but is usually below local limits for sanity sewers. It probably does not meet EPA requirements for drainage outside or to storm sewers.
Another option is to heat the condensate and boil off the water. This results in the maximum condensing of contaminates and the lowest disposal cost. However, installation, operation, procurement, and maintenance costs are higher. As the water is boiled, the condensed water can be disposed of without concern.
Please contact Harris Equipment for advise on the best system for your application |
