b'FAQsQ:On my pulse-jet collector every time a row of bagsQ:Is there a formula that I can use to determine theis cleaned I get a puff of smoke up the stack. collection efficiency of my baghouse? Other than that it runs fine. What can I do toA:To determine collector efficiency divide the emissionseliminate puffing ?(grains\\SCFM) or mg\\Cubic Meters by the incoming A: f your baghouse is operating fine except during theGrain Loading (grains\\SCFM), then multiply by 100. This Icleaning cycle then you might be cleaning too frequently,will be the collector efficiency in percentage. Regulator have too light a dust loading, or the material collectedagencies like to see this number for their records. In is not conducive to building a dust cake in which casereality, unless you perform costly emissions testing, it is you should consider using a pre-coat material (see Pre- difficult to determine a true number. Most collectors can Guard page 24) or modifying the operation of theeasily provide efficiencies over 99%.baghouse. If there is little or no dust cake on the bags the pulse action is doing nothing more than working the dust particles through the cross section of the filterQ:just installed a new set of bags in my baghouse. Imedia. Check your differential pressure at the time ofDo I need to do anything special when I go to start cleaning. If you have on demand pulsing set the valuesit up for the first time? to a higher delta P. If you have timed cycle cleaningA:Baghouse start-up after re-bagging is extremely critical.lengthen the time between cycles. Improper start-ups are a leading source of immediate or premature bag failure. A well-executed start-up will insure a long useful bag life and optimum baghouse Q:How often should I change my bags?performance. Start-up procedures vary with both theA:Filter bags are a consumable item. They do wear out,temperature of the gas stream and the type of particulate blind off, burn up and get attacked by chemicals. Justbeing collected. Unless the baghouse is being used as like the oil and air filter in your car they need to bethe actual product recovery station for the powder, it is replaced to keep you running at optimum performance. Arecommended that bags be conditioned with a pre- coat differential pressure that remains high even after cleaningpowder (see Pre-Guard page 24). This powder is a key indicator. If the differential pressure cannot dropis introduced near the baghouse inlet and coats the below 7 it is time to change bags. If you observe afilter bags with a permeable cake. This acts as a filter constant dust stream from the stack, it is time to changeenhancement and protects the filter surface in case of your bags. Send in your bags for free analysis (seeabnormal particulates at start-up. Additionally you may Testing Services on page 31). elect or be required to leak test the baghouse. Check out our Maintenance Powders section (page 24) for more information on leak detection and our bag change-outs Q:How long should my filter bags last?section on page 28. A:Many factors affect bag life. Often collectors that were built with certain production rates in mind are now operating at twice their design load. Moisture and chemical upsets can easily take a set of bags out at startup. Typical design criteria on new installations should allow for 2-year bag life. However, for difficult applications you may expect no more than 3 months life if there are no other alternatives. If you are changing your bags more often than once a year you need to have Standard Filter look into your baghouse performance. We can perform a complimentary used bag analysis and determine the right type of filter for your current application to give you the length of service you desire.32 www.standardfilter.com1.800.634.58371.760.929.8559'