(405a) Experimental Simulation of Stable Vs Unstable Behavior of Bag Filter Under Three Common Regeneration Schemes

Bag Filters are integral part of many process plants. A long term stable operation of the bag house is highly desirable for steady and uninterrupted plant operation. Intrinsically the bag house operation consists of filtration and regeneration steps in sequence. The filtration steps are longer while the regeneration steps are shorter in normal conditions. The filter cake (dust deposited on the filter surface) is detached from the filter surface using high pressure air in reverse direction. The supply of the cake detachment air is controlled according to any of the three commonly used schemes. In the first scheme the gas injection is initiated at a higher pressure drop level and terminated as soon as a lower pressure drop level is reached.  In the second scheme the gas injection is initiated at a higher pressure drop level and a fixed number of injections are permitted. In the third scheme the fixed number of air injections is permitted at only fixed intervals. The filter behavior depends on many factors including cake detachment scheme which is very difficult to predict using only the theoretical knowledge. Therefore, In this work, the filter is operated under three cake detachment schemes over a range of operating conditions. The operating conditions are systematically varied to stimulate unstable operation and vice versa. The critical parameters which significantly alter the filter behavior are identified under three schemes, compared and discussed. The reversibility of the filter behavior is also studied. Finally the three schemes are rated for their suitability based on their flexibility to handle the variations in operating parameters.