How Does Evaporation Compare to Other Wastewater Disposal Options?

Why choose evaporation?

• Handles Different Wastewater Streams and Varying Chemistries Simultaneously
• Dramatically Reduces Disposal Volume & Cost
• Eliminates Sewer Discharge Accountability
• Easy to Install, Operate, and Maintain
• Low Operating costs
• Can be Used as a Stand-Alone Solution or as a Complement to Filtration Technologies
• Keeps Wastewater Disposal Under Your Control

Discharge to Sewer

Today’s stringent regulations make the option of direct discharging to a septic system, lakes or rivers virtually non-existent. Even when the option of discharging to the local municipal treatment facility (POTW) exists, the generator of the waste is responsible for making sure the waste is compliant. The allowable discharge limits continue to become more strict as local regulations take effect and, as always, the creator of the waste is responsible for proving sewer compliance.

Off-Site Hauling

The advantages to off-site hauling include paying for only what you dispose of and no investment in capital equipment. There are, however, several disadvantages as well. Costs tend to be high especially when you consider 70-95% of what you are disposing is water. There is also liability, as a company is responsible and liable for the wastewater they generate and dispose of; forever.

Filtration Technology

This technology utilizes filters in one form or another to separate contaminants from the wastewater. Examples of this technology include ultrafiltration and reverse osmosis. The technology tends to be more complex and finicky than evaporation and requires more manpower. The discharge effluent from this technology must be monitored, which creates additional hassle and expense, or it must be hauled off-site. Since the reject volume from this technology tends to be much higher then evaporator residue, the cost to haul off-site is also higher. Filtration also has trouble handling multiple waste streams and does not completely address emulsified oils, chemical oxygen demand (COD), or dissolved solids.

Chemical Treatment

Treatment of industrial wastewater using traditional chemical treatment and physical separation (chem/phys treatment) became popular as a method for gross contaminant removal in the 1950's.

Since enactment of the 1973 Federal Clean Water Act, the permittable discharge limits have become increasingly strict, causing a drop in popularity of this treatment methodology. The labor-intensive nature and chemical handling requirements of this treatment are also reasons for the decline in popularity.

Regardless of the waste stream, chemical treatment requires adherence to a multi-step procedure. For oily water application, the procedure often referred to as chemical splitting, involves lowering the pH of the wastewater with acidic chemistry (H2SO4, HCl) to a range of 3-4, which causes the oil to separate from the water. The oil is then decanted from the water surface. After decanting, the pH is elevated to an acceptable range for discharge (typically 6.5-8.5). Prior to discharging to the sewer or tributary, an analysis of the treated wastewater must be completed to confirm compliance.

Evaporation

Evaporation offers the simplest and most effective approach to wastewater minimization. Because it is able to handle a wide range of waste streams simultaneously, it is a good choice when manufacturing processes may expand or change in the future.