Latest systems help manufacturers remain in compliance with standards while reducing the cost of treatment, labour and disposal
Manufacturers of paints, coatings and sealants must meet regional and local wastewater requirements for effluent, including those under the government mandates. Failing to do so can result in severe fines that quickly escalate. Water-based paint, enamel-based paint, wood stains, adhesives, sealants and coatings contain many organic solvents and compounds that can contain lead, mercury, zinc, chromium or a variety of other pollutants. Under the US government mandate, for example, 65 pollutants and classes of pollutants have been classified as “toxic pollutants”, of which 126 specific substances have been designated “priority” toxic pollutants.
For manufacturing facilities, this means installing a wastewater treatment system that effectively separates the contaminants from the water so it can be legally discharged into sewer systems or even re-used.
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 industrial wastewater hauled away is also an option, it is extraordinarily expensive. In contrast, it is much more cost effective to treat the industrial wastewater at its source, so treated effluent can go into a sewer and treated sludge passes a toxicity characteristics leaching procedure(TCLP) test and can be disposed of as non-hazardous waste in a local landfill.
Fortunately, complying with regional and local wastewater regulation has become much easier with more fully automated, wastewater treatment systems. Such systems not only reliably meet regulatory wastewater requirements, but also 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 industrial facilities.
An automated wastewater treatment system can eliminate the need to monitor equipment in person while complying with government mandated requirements. Such automated systems separate suspended solids, emulsified oil and other pollutants and encapsulate the contaminants, producing an easily de-waterable sludge in minutes. The water is typically then separated using a de-watering table or bag filters before it is discharged into sewer systems or further filtered for re-use as process water. 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 as a closed loop system for water reuse or provide a legally dischargeable effluent suitable for the sewer system. A new, fully customised system is not always required. In many cases, it can be faster and more cost effective to add to or modify an industrial 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. The volume of wastewater that will be treated is also analysed, 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.
Some manufacturers have turned to an EconoFlow fully automated wastewater system as well as Cleartreat separating agent from Sabo Industrial, a manufacturer of industrial waste treatment equipment and solutions. The system includes a high-volume flow-through mix unit, large capacity feed hopper, bag housing for solids removal, self-indexing dewatering table, and final polishing vessels. Sensors ensure proper material flow and operation, and onscreen audio-visual alerts indicate if anything requires attention.
However, instead of typical in-person monitoring of equipment to correct a problem, the mix chambers’ motors are controlled electronically by HMI and can be remotely adjusted, along with the mix motor speed, and powder feed by Sabo Industrial. The industrial wastewater equipment provider can use the equipment’s integrated webcams as needed to view the mixing chambers for flocculant formation, floc structure, colour and water clarity. Remote access also enables viewing alert conditions on the touchscreen and provides the ability to reset the machine, if needed.
Separating agents
Despite all the advances in automating wastewater treatment equipment any such system requires effective separating agents that 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 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.
Today’s automated systems along with the Cleartreat separating agents can provide manufacturers with an easy, cost-effective alternative so they remain compliant with government ordinances and environmental protection agencies. 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.