Power plants, cement plants, steel plants, smelters, asphalt plants, incinerators, food manufacturers, chemical producers, pharmaceutical producers, and other industrial companies are widely using bag filters to control Dust Emission. On some applications bag filters are also used to capture other product coming out of mills, for example, cement, coal, and other raw materials.
Fabric filters, without doubt, are an extremely efficient pollution control device with the ability to capture 99% plus of dust collected from process gas but with one drawback, they are prone to leaks.
Ongoing performance can easily be achieved by periodic filter bag replacement, as well as filter inspection and monitoring. The optimum timing for a filter bag replacement is one that maximises the length of a bags use, but one that takes place before a significant leak event occurs which could then result in exceeding emission limits and in turn causing the process to stop.
An accurate prediction for bag replacement can be achieved with the aid of a continuous leak detection system. The advantage of this being that the replacement or maintenance of a bag filter can be routinely planned rather than having to stop a process because of the immediate necessity to replace a filter bag. This can result in significant cost-savings particularly when capturing product.
CODEL’s ET301 Triboelectric Sensor, has been successfully applied to a number of bag filter leak detection applications. One example is of six ET 301’s installed on 6 modules of semi-dry NIDTM FGD. Each module consists of an FGD reactor and fabric filter, as a final pollution control device. Outlet ducts from the six FGD modules merge into one duct before entering the stack.
Codel ET 301 sensors are fitted on the outlet from each module, allowing independent monitoring of the bag filters, enabling operators to schedule maintenance more effectively and isolate leaking bags without stopping the plant.