反渗透系统的2m/s流速管道与径流方向模拟分析

Modeling analysis of pipeline and runoff flow direction in reverse osmosis system at flow rate of 2m/s

以反映管道压降的系统模拟软件为工具,以特定基准系统参数及2m/s管道流速为基础,分析了各种径流方向组合的反渗透系统运行工况,提出了全壳产水量与全壳错流比两个分别表征各壳元件污染速度与清污力度的运行指标,证明了各壳元件产水量失衡是其污染失衡的主要原因,明确了目前工程中常用的2m/s流速管道系统中底层膜壳污染最重.

On the basis of particular reference parameters and the flow velocity of 2 m/s, the operational conditions of reverse osmosis （RO） system under different runoff directions were analyzed by using the simulation software which can reflect the pipeline pressure drop. Two operating parameters of water yield and cross flow ratio in a whole membrane shell were proposed to characterize the fouling rate and defouling intensity for each membrane shell, respectively. It is found that non-uniform fouling distribution in each membrane shell was mainly attributed to unbalance water yield. Moreover, the results showed that the membranes at the bottom membrane shells suffered from relative severe fouling during the current applications of RO systems with the flow rate of 2 m/s.