Sedimentation Tank
Sedimentation water treatment
The purpose and function of the secondary clarifier is twofold:
- Allow settling of biomass solids in the Mixed Liquor (biomass slurry) coming out of the aeration tank, to the bottom of the clarifier
- To produce clear supernatant water, in the overflow from the clarifier
- The clarifier tank is only a passive device: All the above actions occur due to gravity.

Pressurised Sand Filter
The pressure sand filter (PSF) is used as a tertiary treatment unit to trap the trace amounts of solids which escape the clarifier, and can typically handle up to 50 mg/l of solids in an economical manner. This unit is essentially a pressure vessel that is filled with graded media (sand and gravel).
Activated Carbon Filter
An activated carbon filter, like the Pressure Sand Filter, is a tertiary treatment unit. It receives the water that is already filtered by the Pressure Sand Filter and improves multiple quality parameters of the water: BOD, COD, clarity (turbidity), colour and odour.

EnviroTek’s system has the following benefits over other conventional treatment systems:
a. Space saving and low cost:
Given the fact that our MBBR technology generates a very small amount of sludge and taking into account its advanced technology, we are thereby able to compact the size of the plant to about 1/3 the size of a normal “activated sludge process”. This in turn saves valuable space and lowers the cost of the plant and the cost involved in sludge disposal.
b. Ease of operation:
The plant is completely automated thereby eliminating the need for a full time plant operator and limiting the responsibility of the customer to carry out manual operating procedures. The bio media is loose and can be easily cleaned/ inspected.
c. Energy Saving:
The substantially larger surface area of our bio media reduces the oxidation area thereby limiting energy required to aerate it.
d. Easy installation
The plant built by us being a CBU (completely built unit) requires wiring and only a piping connection from the raw water tank and a connection to the permeate collection tank thereby completely simplifying the process of installation at the site.