Efficiency in Waste Water Treatment for Local Authorities

The biochemical cleansing and waste water treatment can be solved ideally with modern technology.

A comparison of different processing methods shows that the technological and construction elements for a solution in waste water; the quality of the sludge and the stability of the processes vary substantially. Hence realistic investment in waste water technology for communal use should be subject to the following criteria:

  • investment cost (construction & technology) in relation to site size
  • flexibility on costing (energy, sludge treatment, staff & sundry expenses)
  • ROI (return on investment)
  • smell, sludge stability
  • stable results where hydraulic & logistic expenses are variable
  • breakdown, maintenance time & incidence of repair

Intelligent Control of Substances

The activated sludge process relating to sludge is one of the most effective methods used for waste water treatment by Local Authorities. With this method, any plant designed in accordance with regulation ATV A 131 can be catered for.

In comparison with the percolating filter method, where bacteria and other organisms are immobilised in controlled surfaces, the degradation process allows these to be irradiated naturally. To achieve an ideal reduction of carbon (COD), nitrogen (ammonia, nitrate) plus phosphate compounds, a proper aeration - endogenous conditions in the (nitrification/denitrification) must be provided in every phase of the operation. Only then can various microorganisms function efficiently.


A high level of cleansing requires:

  1. a process related, intelligent flow of substances (return sludge, circulation, inlet outlet, withdrawal of sludge) in conjunction with
  2. a higher level of aeration (homogeneous spread and rest phase in the activated sludge tank).

Plants utilising the BIOCOS process meet the standards given above and offer the operator stability and high quality results. Use of a special system involving a switch between Nitrification (intense large surface aeration) and Denitrification (endogenous) ensures an open system of operation with the BIOCOS process.

Hence, the RATEMA engineers have chosen the BIOCOS process, especially because a higher level of cleansing with less input can be achieved (savings of final clarification tanks, scraper, sludge circulation pumps and the related piping).
This is an advantage that benefits less technologically orientated countries.