Environmental Hydrotech, Inc.
3 Hixson Road · Croton-on-Hudson, NY 10520
Tel : (914) 271-0175 Fax: (914) 271-0174
Water Purification Experts - Manufacturer of Reverse Osmosis Systems - Supplier of All Types of Water Filters
A variety of industries generate oily waste water. These oily waste streams present a major pollution control problem and potential liability for the generators. These oily wastes can be grouped into three broad categories:
1. Free floating oil.
2. Unstable oil/water emulsions.
3. Highly stable oil/water emulsions.
Free oil can be readily removed via mechanical separators which use gravity as the driving force. Unstable oil/water emulsions can be mechanically or chemically broken, than gravity separated. Highly stable oil/water emulsions, particularly water soluble oily wastes, require more sophisticated treatment to meet today's effluent requirements. When highly stable oil/water emulsions are introduced to conventional chemical treatment, the dirt, floc and trapped water remain in the oil phase. The sludge requires further stabilization by cracking or filtration before disposal. The water phase from chemical treatment will not meet environmental discharge standards (less than 100 ppm) - worst acceptable case - for most sewer authorities.
Environmental Hydrotech, Inc., (EHI) incorporates tubular ultrafiltration modules which can accommodate heavy concentrations of solids while producing a water phase than can usually be discharged to a sewer with no post treatment and an oil phase that can can be incinerated. Careful selection of membranes and pretreatment must be made, depending on the type of oily wastes to be processed. Waste cutting and grinding oil/water emulsions generally have a pH of about 10, but it could contain various flulants that will require both acidic and basic cleaning agents. Waste oils from steel rolling mills require membranes that are stable up to 70oC and can resist alkaline cleaners. Membranes processing waste oils from alkaline metal degreasing baths require good alkaline stability (pH 9-13) and good temperature stability.
Major Industries with Oily Waste Water Problems
General Metal Working - Water-soluble coolants, cutting and grinding oils, and lubricants used in machining operations. Discharge from parts washer tanks, rinse waters and floor washings.
Primary Metal - Rolling and drawing oils used as lubricants and coolants in ferrous and non ferrous operations.
Waste Collection - Emulsified and water-soluble oil wastes collected by waste haulers from other industries.
Transportation - Oil waste discharges from cleaning operations.
Food processing- Natural fats and oils from animal and plant processing, particularly vegetable oily wastes.
Miscellaneous - Contaminated sumps, storage tanks, collection basins and bilge water.