What are the Methods used in Common Effluent Treatment Plants?
It is clear that the output of industrial wastewater is out of control, as a result of the fast expansion of many industries, each of which creates its own unique combination of toxins.These severely contaminate the surrounding environment. As a result, environmental rules mandate all industrial units to establish common effluent treatment plants, in order to limit untreated wastewater discharge into bodies of water, where land availability is limited.
In this blog, we will discuss about the methods generally used in common effluent treatment plants.
Different methods utilized in CETPs
CETP may be erected as a mixed effluent treatment plant, allowing it to handle many types of wastewaters, from the industries, by utilizing the various methods/steps available inside the CETP. These are some examples:
• Sludge Management
• Preliminary Treatment
• Primary Treatment
• Secondary Treatment
• Post-secondary Care
1. Preliminary or pre-treatment
This is the very first phase of treatment in most CETPs. It uses various sizes of bar screens to remove big solids such as sticks, rags, plastic debris, and so on. This is performed through the flotation and sedimentation process. Other portions of the plants will suffer if they are not removed. Large solid materials are broken down using comminutors, while sand, mud, stones, and other waste are removed using a grit chamber. Although it eliminates many waste elements from effluent, it still retains a number of hazardous chemicals that must be treated before disposal.
2. Primary Treatment
Its major purpose is to use physical treatment technologies to eliminate solid materials from effluent. During this procedure, the effluent is stored in a tank known as the main sedimentation tank, where heavier particles sink to the bottom, and are collected as primary effluent to be treated later, while lighter sediments, scum, and grease are skimmed off the surface, using bar screens and a grit chamber. The residual liquid effluent is now pumped to a secondary treatment facility. This technique eliminates around 70% of TSS (Total suspended Solids).
3. Secondary or Biological Treatment
Using an aerobic biological approach such as the "activated sludge process," this stage eliminates soluble organic debris that has escaped from earlier stages. It consists of an aeration tank, a secondary sedimentation tank, and a secondary clarifier. Microorganisms proliferate and degrade organic materials, when compressed air comes into contact with liquid wastewater. Organic matter sinks to the bottom of a secondary clarifier, and forms secondary effluent, a portion of which is re-circulated, and the remainder is sent to a sludge digester for sludge processing. This process eliminates around 70-80% of biological debris.
4. Tertiary or Disinfection Treatment
In the majority of common effluent treatment plants, this is the ultimate stage. This is the only step that can eliminate 99 percent of pathogenic bacteria from wastewater. It also eliminates any remaining suspended particles, and organic debris that were not eliminated in the preceding phases. It comprises a disinfection procedure that uses disinfectants like UV radiation, and reverse osmosis, to drastically lower the number of contaminants in the water, which will be discharged into natural water bodies.
Common Effluent treatment systems are often made up of a succession of water treatment facilities, where all wastewater collected from water-using operations is consolidated, and treated as a single effluent stream. This centralized technique sequentially processes wastewater. For example, before being handled by a secondary treatment unit, mixed effluent is treated by a primary treatment unit. Biological processes can be advanced after the secondary units. The primary challenge in the construction of such centralized treatment facilities is unit size, and the design of individual treatment units.
Best CETP Manufacturer in India
In conclusion, Netsol Water, have an experience of over 10 years, in the water and wastewater treatment, as well as, expertise in custom-designing and producing industrial wastewater treatment systems, including CETPs. In order to schedule a call with an engineer, or submit a quote request, you can also visit our website. We can guide you through the process of coming up with the best solution, and a reasonable price for your Common effluent treatment system requirements.