Wastewater impacts most, if not all, aspects of our society and lives, and treating it properly is vital to preserving both our health and that of the environment. However, wastewater treatment is not a “one size fits all” matter. Alongside municipal infrastructure for handling sewage, the private sector needs separate means for industrial wastewater treatment. This stems from differences in wastewater composition, scale of operation and regulations concerning waste.
On- and Off-site Treatment
Municipal systems receive wastewater output from a broad area of public and residential buildings. Such wastewater is also generally the same from one source to another within the region, coming from restrooms, bathing, food preparation, laundry, etc. Industrial wastewater, however, varies greatly from one site to another, each requiring specialized treatment. Additionally, the volume of water from one industrial site is small compared to a whole municipal system but can have a higher concentration of contaminants. The presence of on-site treatment does have an upside in that it often enables wastewater to be recycled and reused within the same facility.
Barring weather incidents causing a large influx of stormwater, municipal systems have fairly constant flow rates that they handle, as the overall usage of domestic and municipal water won’t vary significantly over time. However, an industrial site can experience flow peaks and drops corresponding to increased or decreased production. It sometimes becomes necessary to reconfigure the treatment plant to handle changing flow rates. Even decreased wastewater flow can cause problems if the treatment process was designed with high volumes in mind.
Discharging wastewater—either directly into a body of water or into a sewer system—carries significant risks for the local environment. Industrial and commercial sources, in particular, face heavy regulations because of the severity of their pollutants. The National Pollution Discharge Elimination System (NPDES) established by the EPA governs any and all standards, permits and limitations for industrial treatment and discharge; additionally, processing sites may need to consult with public facilities before discharging into sewer systems. As noted, though, many industrial facilities are capable of recycling water, thus minimizing discharge.