3-D Modeling of Gas–Solid Two-Phase Flow in a π-Shaped Centripetal Radial Flow Adsorber

Haoyu Wang,Chunwang Li,Yingshu Liu,Xiong Yang,Chuanzhao Zhang,Xiaojun Ma,Ziyi Li

doi:10.3390/app10020614

Abstract

Radial flow adsorber (RFA) is widely used in large-scale pressure swing adsorption (PSA) oxygen production system because of high air separation. In this study, a 3-D modeling of gas–solid two-phase flow was established for the π-shaped centripetal RFA (CP-π RFA). The pressure difference, temperature changes, velocity profiles and oxygen distributions were comparatively studied using this model. Part of the results have been compared with the experiments results, which shows this model can give an accurately prediction. The results show that the pressure and velocity in the adsorber change greatly near the outer hole and central hole, but the overall pressure and velocity changes in the bed are stable. The oxygen product purity in the adsorbent filling area performed better on oxygen enrichment after eight cycles. The oxygen product flow rate will affect the oxygen production performance. The laws of the pressure, velocity, temperature and oxygen distributions can provide an important technical reference for CP-π RFA in the PSA for oxygen production.

Highlights

The most typical pressure swing adsorption (PSA) process is a two-bed four-step Skarstrom cycle, the schematic is shown in Figure 1 [1]
The mathematical model described above was realized in computational fluid dynamics (CFD)
The flow and heat transfer process in adsorption and separation processes are difficult to verify by experiments

Summary

Introduction

The most typical pressure swing adsorption (PSA) process is a two-bed four-step Skarstrom cycle, the schematic is shown in Figure 1 [1]. The cyclic process consists of pressurization, adsorption, countercurrent blow down and purge. It is the basis for designing more complex PSA processes [2]. The PSA oxygen production system has been widely used in industrial production due to its low energy consumption, simple equipment, and convenient operation. With the continuous increase of air processing capacity and the decrease of the utilization efficiency of adsorbent, oxygen production system is seriously restricted by the development of large-scale and low energy consumption. Conventional large-scale axial flow adsorbers have large void volume percentages, and uneven flow distribution, which will seriously affect the oxygen production [3].

Methods

Results

Conclusion