Automated wastewater treatment for service bays
Automotive service stations, auto body shops, car dealers, truck stops, and car and truck rental agencies with motor vehicle waste disposal wells – floor drains or sinks in service bays that connect to a septic system or dry well – are regulated by environmental agencies.
During normal vehicle repair and maintenance, fluids such as engine oil, transmission fluid, power steering fluid, brake fluid, antifreeze, solvents, and degreasers may drip or spill into floor drains or sinks in service areas. Disposal of these fluids through a motor vehicle waste disposal well may contaminate ground water, so these wells are regulated to prevent ground water contamination in certain areas.
The best management practices described in your permit need to be implemented to minimize the amount of contaminants in your shop wastewater and the wastewater being discharged into the ground and sludge should be monitored to ensure continued compliance.
If your wastewater does not meet drinking water standards, you have two options: install ‘pretreatment equipment’ that treats the wastewater before it goes to the drain [or] close the well according to the permitting authority’s directions.
For any shop that services motor vehicles, this means installing a wastewater treatment system that effectively separate the contaminants from the water so it can be legally discharged into motor vehicle waste disposal wells.
However, traditional wastewater treatment systems can be complex, often requiring multiple steps, a variety of chemicals and a considerable amount of labour. Even when the process is supposedly automated, too often technicians must still monitor the equipment in person. This usually requires oversight of mixing and separation, adding of chemicals, and other tasks required to keep the process moving. Even then, the water produced can still fall below mandated requirements.
Although paying to have motor vehicle wastewater hauled away is also an option, it is extraordinarily expensive. In contrast, it is much more cost effective to treat the wastewater at its source, so treated effluent can go into a motor vehicle waste disposal well. As an alternative, if necessary, with sufficient treatment and accommodation, it could also potentially go into a sewer; and if treated sludge passes a TCLP (Toxicity Characteristics Leaching Procedure) test it could be disposed of as non-hazardous waste in a local landfill.
Fortunately, complying with wastewater regulation has become much easier with more fully automated, wastewater treatment systems. Such systems not only reliably meet regulatory wastewater requirements, but also significantly reduce the cost of treatment, labour and disposal when the proper separating agents are also used.
Cost-Effective, Automated Wastewater Treatment
In contrast to labour-intensive multiple step processes, automated wastewater treatment can help to streamline production, usually with a one-step process, while lowering costs at motor vehicle service facilities.
An automated wastewater treatment system can eliminate the need to monitor equipment in person while complying with mandated requirements. Such automated systems separate suspended solids, emulsified oil and heavy metals, and encapsulate the contaminants, producing an easily de-waterable sludge in minutes, according to motor vehicle service consultants at Sabo Industrial Corp., a New York-based manufacturer, distributor and integrator of industrial waste treatment equipment and solutions, including batch and fully automated systems, Cleartreat separating agents, bag filters, and accessories (available throughout the US and Canada).
The water is typically then separated using a de-watering table or bag filters before it is discharged into motor vehicle waste disposal wells, or potentially sewer systems. Other options for de-watering include using a filter press or rotary drum vacuum. The resulting solids are non-leachable and are considered non-hazardous, so will pass all required testing.
These systems are available as manual batch processors, semi-automatic, automatic and can be designed to provide a legally dischargeable effluent suitable for the sewer system. A new, fully customized system is not always required. In many cases, it can be faster and more cost effective to add to or modify a facility’s current wastewater treatment systems when this is feasible.
However, because every wastewater stream is unique to its industry and application, each wastewater treatment solution must be suited to or specifically tailored to the application.
The first step in evaluating the potential cost savings and effectiveness of a new system is to sample the wastewater to determine its chemical make-up followed by a full review of local water authority requirements, say motor vehicle service consultants at Sabo Industrial.
The volume of wastewater that will be treated is also analyzed, to determine if a batch unit or flow-through system is required. Other considerations include the size restrictions so the system fits within the facility’s available footprint.
Despite all the advances in automating wastewater treatment equipment any such system requires effective separating agents which agglomerate with the solids in the wastewater so the solids can be safely and effectively separated out.
Because of the importance of separating agents for wastewater treatment, Sabo Industrial uses a special type of bentonite clay in a line of wastewater treatment chemicals called ClearTreat. This line of wastewater treatment chemicals is formulated to break oil and water emulsion, provide heavy metals removal, and promote flocculation, agglomeration and suspended solids removal.
Bentonite has a large specific surface area with a net negative charge that makes it a particularly effective adsorbent and ion exchange for wastewater treatment applications to remove heavy metals, organic pollutants, nutrients, etc. As such, bentonite is essential to effectively encapsulate the materials. This can usually be achieved in one-step treatment, which lowers process and disposal costs.
In contrast, polymer-based products do not encapsulate the toxins, so systems that use that type of separating agent are more prone to having waste products leach back out over time or upon further agitation.
In the case of a heavy equipment dealer with six locations in New York and Connecticut, an EconoFlow wastewater treatment system using a bentonite-based ClearTreat formulation was required for wastewater created by equipment washdowns. The wastewater contained oil, grease, suspended solids, heavy metals, and cleaning agents.
For the application, Sabo Industrial supplied an EconoFlow 10-gallon per minute unit, which included a 24-bag filter tank, a single stage bag filter housing, final polishing vessels, and an 850-gallon storage tank for water reuse. The system also has Human Machine Interface (HMI) capabilities that allow remote monitoring and adjustment of the equipment as needed. The system provides reliable, one-step wastewater treatment, and legally dischargeable or reusable effluent.
Today’s automated systems along with the most effective Cleartreat separating agents can provide motor vehicle service shops with an easy, cost-effective alternative so they remain compliant with local ordinances. Although there is a cost to these systems, they do not require much attention and can easily be more economical than paying fines or hauling.