The difference between reverse osmosis high pressure membrane and low pressure membrane
Reverse osmosis (RO) is a process that uses hydraulic pressure to push water through a semi-permeable membrane, which removes dissolved constituents from the water
. High-pressure membrane systems like RO are typically used for this purpose
. The difference between high pressure and low pressure membranes lies in the applied pressure. Standard RO operates at 195 psig, while low-pressure/low-energy (LP/LE) elements operate at 115 psig
. High-pressure reverse osmosis utilizes hydraulic pressure in excess of solution osmotic pressure to drive the transport of water across a semipermeable membrane
.The main difference between high pressure and low pressure membranes is the operating pressure. Low-pressure membranes are operated at pressures ranging from 10 to 30 lb/in. (psi), whereas high-pressure membranes, including nanofiltration, are operated at pressures ranging from 75 to 250 psi. High-pressure membrane filtration requires internal pressures of 1000 psi (70 bar) or higher, while low-pressure microfiltration units require pressures of under 15 psi (1 bar). Additionally, high-pressure membranes are typically used for reverse osmosis (RO) systems which require a tight membrane that retains almost all dissolved species including sugars and salts.