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What is Industrial Wastewater?

The term ‘wastewater’ can have many different meanings depending on the application. But typically, wastewater is divided into two broad categories:

  • Sanitary wastewater, which includes household wastes and human wastes;
  • Industrial wastewater, which is the byproduct of waste from professional applications like businesses, hospitals, manufacturing, and more.

The main difference between the two types of wastewater is the method by which the waste is produced. Unlike sanitary wastewater, which is a natural result of day-to-day life, industrial wastewater is specifically a byproduct of core business practices for a given application. Industrial wastewater is produced at much higher volumes than sanitary wastewater.

Common applications that generate large volumes of industrial wastewater include manufacturing, life sciences, and healthcare. These applications often use water as a solvent, use water as part of a product, or rinse/wash products and equipment on a large scale. Less commonly, spills and accidents can be occasional sources of wastewater.

Why Industrial Wastewater Treatment is Important

Because industrial wastewater is produced at such high volumes, the industrial wastewater treatment process aims to mitigate the amount of dangerous waste, pollutants, and contaminants that get released back into the water system. Companies that produce industrial wastewater are responsible for properly treating it based on guidelines set by the EPA and local governments.

Based on these regulations, any source of industrial wastewater has two options for appropriately treating and discharging their waste:

  • Discharge to a Publicly Owned Treatment Works (POTW)
    Where a sewer system is available, a company may be able to discharge their wastewater to a POTW for treatment and discharge. The POTW may or may not require that the wastewater be treated to some extent prior to discharge. However, the POTW system is limited. The wastewater treatment system at a POTW is designed to deal effectively with sanitary wastes and relies on biological organisms to treat wastewater. This treatment system is limited. Certain industrial wastes can cause many different problems with this system; the volume may be too great, the contaminants may cause problems with the system, or the contaminants may pass through without being treated enough. In these cases, discharges to the POTW are restricted or not allowed. There is generally some treatment required for wastewater before it can be discharged from an industrial plant. This is true for small facilities as well as very large ones. In some cases, the wastewater will need to be treated enough to be discharged directly into the environment. In other cases, limited treatment may be required before the wastewater can be accepted by a POTW. In general, a lower level of treatment is required when wastewater is sent to a POTW because the POTW completes treatment.
  • Discharge to the Environment
    When there is no POTW available, the industry discharges directly to the environment. In this case, all wastewater must be completely treated by the industry. In these instances specifically, it is crucial that industrial wastewater producers appropriately treat their wastewater and remove all dangerous contaminants.

Water Treatment Process

It is important to note that industrial wastewater treatment is sometimes referred to as pre-treatment when the effluent is then discharged to the POTW. Almost every POTW treats water in a similar sequence of steps.

Industrial wastewater treatment can be as simple as a single-stage treatment or as complicated as a multiple-stage or multiple “treatment train.” The process depends on the type of wastewater that the industry produces or the contaminants that are present and need to be removed.

The Types of Wastewater Treatment

Physical Treatment: A process that takes advantage of the physical properties of the wastewater components to achieve separation of some components from others. An example would be screening which is the removal of large solids using a screen or bar system.

Chemical Treatment: Processes that achieve changes in wastewater characteristics through the addition of reaction-causing chemicals. An example includes pH manipulation, where chemicals, acid or base is added to change or neutralize the pH of the wastewater.

Physical/Chemical Treatment: Often both physical and chemical treatment is necessary to achieve a treatment goal. An example of this would be Coagulation. Coagulation is a chemical process in which electrically charged treatment chemicals, such as alum, are added to wastewater to help build large particles that will settle easily. A physical treatment, such as screening, is then needed to remove the large particles.

Biological Treatment: Processes are based on the action of bacteria, microorganisms often referred to as “bugs” to break down compounds present in wastewater. An example would be activated sludge which uses biological organisms to break down wastes.

Types of Industrial Contaminants

There are a wide variety of contaminants and problems which can be encountered in industrial waste streams. Biological contamination can be a source of disease-causing organisms. Chemical contamination can damage both plants and animals through direct poisoning or interference with their activities. Even seemingly innocuous problems such as nutrients in wastewater can cause problems by causing too much plant growth in a river or lake.

There are two types of pollutants or contaminants present in industrial wastewater. Compatible pollutants are the contaminants allowed to be present in safe amounts of wastewater discharged to a POTW. These pollutants, which are also called conventional pollutants, include BOD, FOG, TSS, pH, and certain pathogens or bacteria or other disease-causing organisms.

The other type of contaminants which are incompatible with the POTW are called non-compatible pollutants. These include contaminants such as heavy metals, pH, organic compounds, heat/cold, high volume, sludges/solids, turbidity, radioactivity and odor or color.

How to Properly Treat & Dispose of Your Industrial Wastewater

Because of the many different types of contaminants and the risks they pose, it is critical for industries to properly dispose of their wastewater. If steps are missed, the consequences could be dire for public health and the environment. Make sure your company is taking a thorough and proactive approach to industrial wastewater treatment. Contact Practical Applications today to learn how we can help you properly treat your waste to avoid fines and protect our environment.