UF membranes tackle silica at Indian powerplants

Pentair X-Flow HFS 60 Silica ultrafiltration (UF) membranes are to be used in two projects in India for the removal of colloidal silica from surface water.

Both projects utilize the UF modules to protect the high-pressure boilers in power production facilities.

The HFS 60 Silica tight membrane module is the first hollow-fiber membrane module in a new line of low molecular weight cut-off UF membranes that offers new treatment options. Applications include desalination pretreatment, wastewater treatment in the textile, oil and gas industries, as well as in ultrapure water production in the semiconductor and pharmaceutical industries.

At the Jaypee Nigrie Super Thermal Power Project in Singrauli, Madhya Pradesh, two streams with a total of 3,840 m³/d are treated. In the JK Paper plant in Rayagada, Chhattisgarh, two streams with a total of 6,000 m³/d are treated.

At both installations, the boiler feedwater is treated by a demineralization step before it is purified by Pentair’s HFS 60 membranes. The tight molecular weight cut-off of 10,000 daltons of the membranes offers a colloidal silica removal rate of 99.8%.

By efficiently removing the colloidal silica, Pentair X-Flow provides an alternative for silica removal. The high-pressure boilers are protected from scale deposits, which maximizes performance and prevents turbine failure. The robust HFS 60 membranes are backwashable, offer low energy-consumption, provide high recovery of demineralized water and can be operated at higher pressures.

The silica removal rate is 10 times better than standard UF, no coagulant is needed and the membranes can be used early on in the process as pretreatment instead of polishing.