【原著】スィープ式向流型膜モジュールを用いた 高効率ガス分離プロセスの設計

抄録

We conducted exploratory research of high–efficient membrane processes for gas separation using a sweep counter flow module (SCM). Calculated results for biogas upgrading example were compared by using economic efficiency indexes. When a sweep ratio (SR) is less than 0.1, SCM can be designed resulting to keep the same level of power requirement and reduce the membrane area than that of normal counter flow module (NCM). A recovery of methane, however, can’t exceed over that of NCM. To improve the recovery without losing economical advantage of NCM two stage series (TSS) processes were newly designed by employing a SCM as the first stage (TSFSC) or the second stage (TSSSC). These two processes can yield higher recovery as increasing recycle ratios (RR) of permeates from the second to feeds of the first. Especially, TSSSC designed by SR＝ 0.1 and RR＝ 0.7 ～ 1 using a membrane of α＊≧ 30 is significantly efficient and economical, in which methane recovery is more than 0.9 and membrane area requirement is less than that of NCM keeping the same level of specific power requirement.