Visakhapatnam (also known as Vizag) is a city located in the state of Andhra Pradesh in India that has a growing need for a wider electricity network to serve its citizens and industrial activity. To address this need, Hinduja Power decided to build a 1040 MW coal fired power plant to provide power not only to Visakhapatnam, but also throughout the state and to other states in the southern India through an interstate transmission system.
The Hinduja Power Plant is located on the coast of the Bay of Bengal, and because of this, HNPCL decided to use seawater desalination to treat water for all of the plant’s purposes. The desalination system consists of a self-cleaning cartridge filter, ultrafiltration, biofoulant removal filter, and seawater reverse osmosis (RO). The plant is unique in its low-energy desalination design due to effective pretreatment steps. The system process diagram, as well as the feed and treated water quality analysis is shown below.
In order to ensure that the plant had low energy consumption, steps were taken to ensure that the RO membranes were performing as expected, not under fouled conditions. A combination of ultrafiltration membranes and cartridge filters were chosen as pretreatment to the RO membranes. HNPCL evaluated its seawater reverse osmosis pretreatment options and decided to choose QUA’s Q-SEP membranes due to their ability to produce higher quality effluent water than conventional ultrafiltration membranes.
The primary goal of the UF pretreatment step is to reduce suspended solids, turbidity, and SDI to a point where RO membrane cleaning is minimized. Since seawater has the presence of biofoulants that affect the long-term performance of the RO membranes, careful consideration was taken to assess the best solution for their removal. Combining the Q-SEP ultrafiltration membrane with a biofoulant removal filter reduced the biofoulant load on the downstream RO. This pretreatment increased the life expectancy of the RO and kept the RO pump power consumption low.
To learn more, download the full case study.