As I’ve previously shared, surcharges from publicly owned treatment works (POTWs) continue to rise for food and beverage companies. So, is it worth investing in a wastewater treatment system? The old plan of doing some light pretreatment and sending the effluent to the sewer no longer makes sense for larger food and beverage companies. Along with rising costs, other issues include more stringent permit levels, increased sampling requirements, and POTWs throwing out fines should you not meet your discharge limitations.
Which treatment system is right for you?
If you have decided that it makes sense to do a treatment system and you need more than the typical storage tank and pH control, you are going to require higher level treatment such as biological treatment. So, what type of system do you put in? The first step in moving to a biological treatment is to decide if aerobic or anaerobic is the best fit to treat your waste stream. Successful projects began at the evaluation stage so that you can select the right treatment system that will meet your permit requirements and reduce your monthly surcharge costs.
Benefits of anaerobic treatment
Anaerobic treatment continues to grow in popularity for the food and beverage industry because of its ability to process wastewater and produce a useable energy source. Anaerobic digestion is a biological process in which organic wastes are broken down by microorganisms in the absence of oxygen. Anaerobic treatment is typically utilized to treat higher temperature, high-strength industrial wastewater containing high concentrations of biodegradable organic matter. This energy-efficient process reliably removes much of the biochemical oxygen demand (BOD), chemical oxygen demand (COD), and total suspended solids (TSS) from wastewater.
As organics are removed from the wastewater during the anaerobic digestion process, methane-rich biogas is produced. This valuable biogas can be captured, treated, and used as a source of renewable energy to displace fossil fuels or to generate heat or electricity. Such a waste-to-energy approach helps treatment plants recover money-saving resources. Compared to aerobic treatment systems, anaerobic systems use substantially less energy, require fewer chemicals, and incur lower sludge handling costs. Anaerobic digestion produces very little excess sludge, and the agriculturally beneficial sludge can safely be applied to land as fertilizer.
How can this save you money?
Because biogas may be used for heat or electrical power, waste heat can be used to meet the heating and cooling requirements for the plant. Concentrating nutrients to a relatively small volume for removal from the site can reduce the land required for liquid waste application. In some cases, income can be obtained from the processing of imported wastes, the sale of organic nutrients, greenhouse gas credits, and the sale of power. Power tax credits may also be available for each kilowatt hour (kWh) of power produced. Greenhouse tax credits may become available for each ton of carbon recycled.
Anaerobic treatment might be the way to go for you!
The benefits of this treatment system are varied, and granular anaerobic treatment systems are the most common ones used to treat industrial wastewater. Implementing low-cost operational changes, such as the following, can also increase their economic viability:
- Reducing the pH of anaerobic effluent can reduce caustic use without jeopardizing performance
- Modifying the reactor recycle return location can reduce suspended solids concentrations in effluent
- Controlling petroleum fats, oils, and greases (FOG) can improve performance
- Re-piping influent feed can reduce maintenance requirements and ensure optimal wastewater distribution
Changing chemical-addition locations can reduce maintenance requirements and improve system performance. As always, an important facet of deciding which treatment system is right for you is working with an experienced wastewater professional. Mead & Hunt can help you select the right system for your facility’s unique needs.
