| 摘要 |
<p>A method of controlling the cleaning process for the cleaning of textile barrier filters, for example bag filters, subsequent to dust precipitation on the filter material. The cleaning is carried out with a cleaning system comprising means for distributing compressed air pulses to the filter bags. The gas flow often shows great variations in flow, temperature and dust content, thereby giving rise to problems in the control of the cleaning process in such a manner, that neither over-cleaning nor under-cleaning occurs. For the control, the filter load vf is measured which is the ratio of the gas flow (m3/s) and the filter area (m2), as well as the pressure drop Pf over the filter material. At applications with great temperature variations of the gas, also the absolute temperature T is measured. The measuring results are processed in an electronic unit for calculating the filter resistance S, which is the ration Pf/vf, possibly standardized to a reference temperature To by multiplication with the ratio (To/T).alpha., where .alpha. is a constant with the value 0.76 at gas temperatures below 200.degree.C. Through the filter resistance S the cleaning process is controlled by acting upon the cleaning interval, the time interval between the cleaning pulses, the cleaning pressure of the cleaning pulse or the duration thereof.</p> |
