Can algae Intervention improve STPs?

Can algae Intervention improve STPs?


Can the conventional STPs be improved through algae intervention?


A sewage treatment plant (“STP”) has to handle the designed quantity of sewage and deliver satisfactory quality of treated water, on a consistent, sustained basis over typically 10-15 years. This requires proper design and engineering; followed by proper operation and maintenance throughout its life. There are as many variations in the design and engineering of an STP as there are permutations and combinations of Builders/ developers, architects, Utility Consultants, Vendors. Conceptually, the process is extremely simple: A small amount of microorganisms converts a large mass of polluted water into clean water. This process also produces a co-product: A vastly reduced, compact solid biomass (the excess microorganisms produced by growth and multiplication of the original population of microorganisms).

We need an STP that

  1. Achieves the desired results on a consistent and sustained basis
  2. Is robust and reliable, and lasts for at least 10-15 years without major repairs
  3. Needs minimum amounts of money, energy and chemicals to achieve the desired treated water Quality
  4. Is easy to operate and maintain.

Beneļ¬ts of a well-run STP

The primary benefits of a well-run STP are

  1. Assured availability of water for various secondary uses
  2. Enormous savings in fresh water costs
  3. Lesser Environmental Degradation
  4. Improved public Health


Odour, BOD, COD , N and P and coliform bacteria and other harmful chemicals are to be reduced to desirable limits.

A typical STP should have the following components:

Algae Intervention

We can improve the performance of a conventional STP by intervening with micro algae at Aeration Tank 

Phycospectrum Environmental Research Centre (PERC), Chennai has developed a micro algae intervention technology which works perfectly to enhance the performance of STP. Sewage treatment using micro algae has been extensively worked out by Oswald and others from 1960s (Oswald and Gotaas, 1957; Benemann et al 1980). There is a symbiotic association between micro algae and bacteria in degrading organic pollutants and further mineralization resulting in a significant reduction in the majority of critical parameters like odour, colour, total dissolved solids, biological oxygen demand, chemical oxygen demand and sludge.