Technical parameters of tubular membrane systems

Configuration of tubular membrane system

Features

◆ The special WIT-m membrane operation system, combining micro-flocculation, microfiltration and pulse back-washing system, completely solve the blocking problem of microfiltrations, ensuring the long-term stability.

◆ The combined pulse backwashing system is applied. It is a taboo that compressed are directly contacts the membrane for back-washing. WIT-m membranes are allowed to apply pulsed compressed air (≤0.45 MPa) for back-washing, breaking though the taboo theoretical and practically. The backwashing lasts 92 s, and the ratio of filtration time to back-washing time is 16:1. The membrane flux recovery performance is beyond the water back-washing。

◆Chemical enhanced back-washing, applied per 15-20 normal back washing cycles, can recover the membrane flux efficiently and minimize the chemical cleaning cycles, but it requires soaking the membranes in the chemical solution for 15 min before back-washing.

◆ Due to the lower cross-flow rates (0.5-1.0 m/s) of WIT-m membrane module, the required electricity is only 0.16-0.32 W/ton water. Other similar membrane systems adopting higher cross-flow rates (3-5 m/s) cost 3-5 W/ton water.

◆ The fluxes of WIT-m tubular membranes are in MF range, but the permeate turbidity is similar to that of UF permeates.