After installing an ElectroPulse Electrocoagulation System to clean its wastewater, Ritchie Bros. Heavy Equipment Auctioneers has achieved successful contaminant separation and exceeded its own water quality specifications, according to an OilTrap Environmental case study.
The EP3-WR OilTrap ElectroPulse Electrocoagulation System has a 15 gallon per minute capacity. The Olympia, Wash.-based Ritchie Bros. used it to treat wastewater resulting from the cleaning of heavy earth-moving equipment.
The wastewater was dark brown in color and opaque, contained light floating oil and grease, and gross solids that did not settle quickly. Furthermore, the pretreated liquid had an oily odor and a pH of 8.75.
For the water to qualify for reuse it needed to be free of oil and grease, heavy metals and solids measuring greater than 1 micron, the case study says.
In addition to separating the contaminants, the electrocoagulation system produced treated water that was clear and odorless (pictured).
Treated water feeds back to two 5-gallon-per-minute pressure washers. The ElectroPulse water system is zero discharge, recycling 100 percent of the treated water, the case study says.
Electrocoagulation works by energizing wastewater contaminants such as suspended solids, emulsified oil and grease and heavy metals with a DC electrical current. The tiny particles accept a positive and negative charge causing them to bond together “like miniature magnets,” the case study says.
Contaminants are then removed from clear phase of the water without the use of filters and deposited in a sludge tank.
In October, Siemens Water Technologies and Texas A&M AgriLife Research agreed to continue to develop and commercialize a chemical-based technology that the organizations say will more efficiently and cost-effectively remove heavy metals from water and wastewater at power utility, mining, refinery and remediation sites.
In a single process unaffected by temperature or pH-levels, the technology can remove selenium, mercury, zinc, copper, chromium and other heavy metals as well as metalloids to meet National Pollutant Discharge Elimination System limits.