Case Study

Grundfos Dosing Pumps Play Important Role In Indian Desalination Plant

Source: Grundfos
Grundfos desal in India

In Minjur, a town in Thiruvallur district of Chennai in India, will soon be able to overcome a hurdle facing many growing urban areas: an adequate supply of drinking water. Grundfos dosing pumps help solve this problem by contributing to one of the world's largest sea-water desalination plants. This 100-million litres per day (MLD) desalination plant is being built by Chennai Metrowater and technology partner Befesa Construcciiony Tecnologia Ambiental of Spain. It treats seawater through reverse osmosis (RO) to make it potable.

Spread out across a 60-acre site, the plant contains five modules of 20 MLD each. Among impressive details are an intake tower that draws sea water from 10 metres below sea level, and separate pipelines to draw raw water and discharge wastewater.

An important part of the entire process is chemical adjustment both before and after the removal of salts. Befesa turned to Grundfos for custom-made dosing solutions to fit the bill.

The situation
The sea water desalination plant in Minjur will draw over 230 million litres of seawater each day in order to produce 100 million litres of potable water each day. This is equal to 100,000 m3/day. The RO process can be divided in 3 main processes:

  • Pre-treatment: Seawater is filtered and chemically adjusted before proceeding.
  • Reverse Osmosis: Seawater passes across the membranes for salt removal
  • Post-treatment: The treated water is chemically adjusted in order to make it drinkable.