An efficient and continuous filter operation for dust‐laden flue gas based on a self‐cleaning stainless steel weaved filter

Abstract

Advanced filtration technologies of the high‐temperature flue gas are crucial for lower emission of dust particles and higher heat recovery. An efficient and continuous filter for high‐temperature flue gas based on a self‐cleaning stainless steel fabric is proposed in this article. Analysis of the microstructure of stainless steel fabric is conducted and derived the optimal structural parameters of the fabric. Considering uniformity of flow field, the structure of filter bag and arrangement of bags of the filter are optimized. Based on the optimal condition, single‐bag experiments are conducted, which show that the filtration efficiency and pressure drop got stabilized (i.e., 99.8% and 1222 Pa) with enough operation time and only affected by filtration superficial velocity. The dust cake structure could reach dynamic self‐equilibrium in the overall structure, verifying that self‐cleaning can be achieved applying stainless steel fabric. A pilot‐scale high‐temperature flue gas system is set up and the results indicate that the filtration efficiency reaches stable and maintains above 99.9% with 1440 h of uninterrupted service at 793 ~ 809°C, and the outlet dust concentration of flue gas is less than 8.3 mg/m3.