The entire treatment process starts with a pre-treatment phase. It’s the stage which works to remove materials conveniently collected from raw wastewater so that they can’t clog or damage skimmers or pumps of primary sewage treatment clarifiers. These materials could be leaves, tree limbs, trash etc. The sewage water gets thoroughly strained to sift out large objects that are carried through sewage stream. An automatic mechanical raked-bar screen is the most common aide here, especially for modern sewage treatment plants. However, smaller plants might go for manual screening.
The solids collected are disposed in landfills or else are incinerated. The pre-treatment phase generally comprises of grit removal.
In case of primary treatment phase, the sewage is flown through big tanks or “primary sedimentation tanks” or “primary clarifiers”. These big tanks help sludge to settle down & make floating materials like oil & grease to rise up to the upper surface for an easy skimming. The fundamental mission of primary sedimentation phase is to generate a homogenous fluid that can be treated biologically as well as a sludge which could be separately processed or treated.
The primary clarifiers are designed with mechanical scrapers that continuously drive the gathered sludge to a hopper located at tank base. It’s from the hopper, the sludge is pumped to advanced treatment stages.
This phase is dedicated to thoroughly degrade biological parts of sewage – the very biological contents derived from food waste, human waste, detergent and soap. It’s the aerobic biological procedure that goes to treat settled sewage fluid in STPs. The process could be performed in several ways and in all the methods, protozoa and bacteria consume the soluble organic biodegradable contaminants & bind a fair share of lesser soluble fractions to floe. The secondary treatment processes could be suspended-growth or fixed-film.
It’s the final stage that aims to further enhance the quality of treated wastewater before it’s ultimately released to receiving environ.
Kelvin Water Technologies is one of the most renowned STP specialists in India. Our trained and seasoned wastewater treatment engineers are always here to help you with any assistance regarding servicing & maintenance of sewage treatment plants – and that too at highly reasonable costs.