Miller Magazine Issue: 147 March 2022

79 COVER STORY MILLER / march 2022 the studies carried out in flour and semo- lina mills, it has been observed that only 15% of the jet filters operate at their nor- mal performance value, and the remain- ing 85% are used far below their perfor- mance. It has been determined that 20% of these filters do not work at all. Despite such a high-performance loss, it is very difficult to detect the malfunction that oc- curs because the filter areas are above the need. Problems in filters are always reflected in production. It is an essential requirement that all malfunctions be de- tected electronically, not by human eyes. 3.1. Problems Experienced in the Production Process Due to Jet Filter In flour production, suction provided by the pneumatic fan must be at a con- stant value. In this way, the air velocity and the amount of load going to the pas- sages could be realized at the planned values, so the targeted extraction rate could be obtained at the highest tonnage. Normally, a suction of around 100 mbar is provided by the pneumatics. When clean filter bags are first installed, a pressure drop of around 2 mbar occurs and a suction of around 98 mbar is transferred to production. However, over time, the filter bags begin to fill up and the pressure drop reaches 25 mbar lev- els. In this case, the suction that could be transferred to production was decreased at 75% and it drops 75 mbar. This decrease causes a decrease in tonnage. If the same tonnage is insisted on, then the ash value will increase and the extraction rate will decrease. As an alternative solution, it is seen that the fan speed is increased at a certain rate with the driver. In this case, the problem can be solved by increasing the flow rate at the same rate, but the energy consumption will increase as the cubic of the increase in the flow rate and the energy consumption will reach very high values. This problem can only be solved by keeping the pressure loss in the jet filter bags at a constant value of around 10mbar. 3.2. Energy Consumption of JPF JPFs are the equipment that consumes the most en- Figure 1. Jet Pulsed Filter System