dust collector troubleshooting guide

Many of these issues can be resolved with a simple maintenance procedure; others may require a qualified service technician to implement a solution a particular problem. Your email address will not be published. Thanks.. You can measure it both before and after if you wantbut usually its best to know the temp before it enters the unit so you can use that information to guide fabric choice among other operating variables. Is the dust not able to be removed from the Filter Bags by the cleaning mechanism? BH has started to condensate and plug apu lines problems daily. If you are still having problems you can consider having us come out to inspect your system. Kindly help me to solve this doubt.. Air to cloth ratio is 1:1. It sounds like you have dirty air escaping from the view ports on your unit, is that correct? I need more information to determine exactly whats happening but it could be the high humidity gets sucked into the baghouse and its causing condensation thats caking up the dust into a thick, wet layer on the bags that the cleaning system then has a hard time removing. I work at a grain elevator and we have a serious issue. You must have excess air coming into the kettle beyond that supplied by the dust collection system. Is the Baghouse the undersized for the application? Check hopper discharge and 55 gal drum lid for leaks allowing re-entrainment of dust. 2. In fact, any of those methods will usually cause further damage to the filters as they are not designed to withstand that treatment. His articles have been published not only on Baghouse.com , but also on other industry related blogs and sites. Also the filters could be installed incorrectly. With low temps on baghouse we are not getting the moisture out. We plan on placing a Humidity/ temperature/ dew point transmitter EE 310 ( has 2 x 4-20 Outputs and 2 Alarm outputs)) With nearly a decade of hands-on working experience in the industry, Dominicks knowledge of the industry goes beyond a mere classroom education. With all the problems listed something has definitely changed. After temper process we degerm the corn then dry it down for customer specs. Any moisture in a baghouse is going to make things difficult. Its best to keep it under 5,000 ft unless absolutely necessary as running such a powerful fan will be expensive and the baghouse will need to be reinforced to handle the extra pressure. Can you give any solution for this. Good points Dustin! Can you suggest me by using your bag filter(PTFE fabric) can this problem be solved. Since they are shorter the air has more time to slow down and allow for the heavier particles to drop out before reaching the filters. Could it be that the exhaust fan is not exhausting enough air from the baghouse? Are the different compartmental isolation dampener valves functioning properly? If correct, the lower pressures indicate that your fan is not pulling as hard since the clean side vacuum is much lower. I do not see any fluctuations when its in use. I did mean to say check the airlock but anyways. It was discovered that after the bags were changed and the mill started up, that blaine on the cement started to drop after 4 hours of operation. Is the Reverse Air Fan powering up/running properly? Any help would be much appreciated. Try switching to PTFE membrane coating. How I defined my baghouses, per flow rate? Why its happened??? If the pleat depth is too short or the pleat count too high the same bridge effect can happen between the pleats on the filters. From reading your blog it looks like I should be looking at leakage causing moisture and bridging.? instead of using pulsation we are getting high pressure drop across the bagfilters(50-60 mmHg). When that trips the suction is gone and a lot of dust drops. (Namely, the type of unit, filter style, number of filters, fabric/treatment used, air to cloth ratio, total CFM, etc.). If it drops below that you will have the product falling out and building up in your baghouse. Is the cleaning cycle set to the proper interval? 19 vs. 27 initially. (I believe thats what you have here based on your comment.) can. You should also try having a rotary airlock to make sure the dust is emptying at all times and does not have a chance to buildup. 3R5. We have bag house at cement plant RM area ,main bag house after we replaced all Fiberglass bags still dust emissions. The valves wont fire if there is no air in the air header tank. If the duct is being closed off by build up of dust you have a different issue. Is the manifold pressure within the manufacturers suggested range? Kindly help please. Hi filter bha elements pleated Our 12 bags will fill up with dust but not the 55 gal Done inspection on filter bags, found 2 bags full of dust inside. If its a moisture problem you can look at ways to lower the moisture content before it enters the baghouse or keep the temperature high enough above the dew point so its not an issue. Upon restart after the cleaning the system appeared to be operation properly, but within a few minutes we noticed the amps dropping from 100 to 65. (If your Blower output is normal) Has the Ductwork System been inspected for obstructions, leaks or design flaws that increase static resistance? Sorry about not emailing direct. Are any other Baghouse functions affected when Shaking process begins (Fan, or Isolation Dampener, etc)? Purging sequence,purging air pressure,bag size etc. Air Pollution Control & Managing Industrial Dust, How to Replace Your Dust Collector Diaphragm Valve. If our dust collector is working proper, what I feel that we should have only negative pressure. This is causing the issues with the increase airspeed, etc. Our bag filter house is not discharging dust continuously. Bags are newly replaced with ptfe membranes type. M&B Consulting Services. Is your dust collector showing signs of trouble ahead? What kind of baghouse is it? Thanks for the help. If its settling in the bottom of the duct and building up you could have an issue with product dropout from a air speed within the duct (dropping below the minimum conveying velocity). Andy Tomasello This tends to happen with sticky dusts or dusts that can easily form clumps, or if there is a high moisture level. This phenomenon repeats. Your email address will not be published. I dont see how you would have positive pressure on the clean side, regardless of whether the filters are dirty or not. When we started operations we were within the 4DP and static pressures for dirty and clean sides have generally been -23 & -27 at the start. No matter what the cause is there is certainly a better way to operate. Most are between 3:1 6:1. It sounds like you are having problems with the collection system not being able to keep up with the dust generated. I do not see it continuously pulsing down when I inspect the baghouse, and the instrumentation and pulse board are all working fine according to my troubleshooting. Hi Even if the filters are not blinded, the baghouse could be inadequately sized to allow the needed airflow through the system, thus building up pressure on the kettle. We are having trouble getting the baghouse inlet and outlet temperatures up high enough. But is there a way to support this dust system without replacing? How do you monitor emissions levels? Wondering where and how the dust flows through those 2 bags? What could cause this? Required fields are marked *. THERE ARE VUMES & DUST IN THE AREA. It is disastrous as the inlet duct becomes smaller, velocity increases and the bottoms of the bags get sand / ash blasted through. There is a heap getting formed in the middle of bottom hopper and it is getting hold up over the screw. Have the Filter Bags been checked to have proper tension? check and monitor your gauges to see what the pressure is doing. It could be that the pellets are throwing an increased/decreased dust load on the filters and your cleaning settings are no longer optimal for that mix. Heres a few things to try: Have all gauges and pressures sensors been checked for accuracy? Hi, How old are your bags? OUR FILTER BAG HOUSE IS NOT SUCING THE AIR WELL. I have started my plant after 4 months shut down. The Lines feeding our bag house are having excessive product build up. After replacing bags and vacuuming the clean side, the DP is still achievable but static pressures of -15 & -19. This issue did not happen until 15 years ago from what I have heard but it had gotten so bad. 115 diameter x 3 meter long This is not a problem with clear hoppers. Are the Bags being cleaned at the proper intervals? You are getting the point. Thanks for your reply. This is a rotary step baghouse not a pulse jet. Ill follow up by email with you to see if we can get some more information and help you. You may also have benefited from PTFE membrane to help with dust release, or the pulse jet settings could have been wrong. i am also facing same issue hot steam is going through the bag filter then always filters getting blocked,,so what is the best solution for this issue ,150c temp under ruining this bags. You do not need to battle with abraded bags for the long term. We offer our audit services at very reasonable rates and even offer rebates that can potentially make our audits free. Phone: (702) 848-3990. Cyclones do not have pulse jets, baghouses have pulse jets. In some units you have a trough hopper with a screw or drag conveyor that moves material to the middle or the end to discharge through an airlock. Many times, users do more damage to their bags by attempting to clean them than they do just leaving them alone. Thank you If the DP is still high even with new filters its possible the baghouse is undersized. It sounds like you are differing from product drop out in the ductlines. If the bags were damaged by not precoating them, then you will need to get a new set of filters. Otherwise, you can try making sure that you have everything well above the dew point, from the ductwork, to insulating the baghouse, especially around contact points. If you are using a fan that blows back into the unit this is actually a reverse air dust collector. Inspect rubber diaphragms and orsolenoid sealsand replace as needed. Additional Questions: Do the Bags have the proper amount of tension? bosch repair Hello, I have looked many places and we would like to install it in house since it doesnt look too complicated. If too much dust falls off at once (especially with certain sticky dusts that accumulate easily) the dust can bridge across the hopper discharge and the resulting blockage will pile up high into the collector. DP 85 mmWG Side note. No matter if its 50% up or 100% doesnt seam to slow or help with steaming. one other trick that might do it would be to jump up your clean cycle timing to get the bags running less cake. http://www.ecefast.com.au/humidity-temperature-dew-point-transmitter-ee29-31 Leakages in the inter connecting ducts, bag filter as well as filter bags, Experiencing high positive pressure at the roller mill house. As in the pulse valve opens for 7.2 seconds each time? Any ideas on what could be causing this. Note:conveyors are covered. Less common issues could be the baghouse is undersized for the airflow/dust loading and the cleaning system cannot keep up. Likely the air is bottlenecking in the baghouse because the filters are clogged and restricting the airflow. The blow pipes could be misaligned, insufficient airflow in the header, wrong settings on the timer board, etc. Even taking them out and blowing them down with compressed air will not do the trick. If you are having discharge problems it could indicate a leak around the airlock, high dust loading (too high for the size baghouse indicating high air to cloth ratio, can/interstitial velocity, etc.) Im going to replace the airlock, the bags have been done but something I have noticed it gets bad on humid days. The only real solution for blinded bags is to replace them. However, I unable to find any hole or torn at those 2 old bags. Otherwise, it might the cleaning system has low air pressure, the valves are in bad condition or the cleaning controller is not functioning properly. IT could very well be the problem. You may need to sufficiently precoat the bags or switch to a media with ePTFE membrane or a similar high efficiency media. Rotary step is not a standard term so Im not sure what you are referring to. Has the raw materials supplier changed anything? Thanks for contacting us. are in the correct setting. Is there excess moisture in the Baghouse? Insulation and occasionally heated hoppers/conveyors are used to solve the problem. The most common variations in Baghouse design regard the cleaning mechanism. I have check rotation on blower motor and also to make sure the dampner is working there and blades are not sticking / stopping air flow. We have noticed that the issue started after that we have changed the top section of the baghouse plenum (due to corrosion issue). Good Day, When you are looking at design and maintenance, we talk about them in terms of CFM, number of bags, style of baghouse (pulse-jet, reverse-air) type of bags (aramid bags, top load, bottom load, etc.). Years ago we did try some short pleated (shop vac style) filters. Always maintain clean dry air for the cleaning system. Actually we are having total 8 same type of bag house system but facing this problem in particular 1 syatem so undersize is not an issue i think. You can try to reduce the moisture content in the processas its really not good practice to send any moisture into your baghouse if you can avoid it. Great presentation! The fabric filter length is 1.7 metres with 3-5bar of pressure(pulse jet) used to clean the bag..if we increase the bag length to 3meters.. Would the pulse jet air used to clean the bag will be same or need to be increased? So as you said, keep the DP as low as possible and keep the cake from forming too muchit gives a place for the moisture to condense and form hard, sticky cake. It could be an issue with the pulse valves. I am facing a problem in my bag house. When it blocks up it is mostly at back fills on the entry of the oxide in the bag house any ideas will be welcomed thanks Michael. Is the opening for the Screw Conveyor (Or similar device) of adequate size? Is the motor pulling the specified proper amount of Amps? It might require insulated ductwork or unit heaters to keep the unit above the dew point or a combination of things. Please help with any suggestions thanks, This also requires following a strict startup/shutdown procedure to make sure you dont have condensation problems at the beginning or end of a shift. It sounds like you have the gas bypassing the unit. As soon as he opens open the vacuum breaker, the DP becomes zero and then starts increasing as soon as the deashing starts. This indicates your airspeed in your ductwork is below the minimum conveying velocity for the product. Unit #5105 Your pulse valves could be old and leaking when they fire. This is especially common on larger baghouses or when inexperienced laborers do the changeout as they could easily install a few bags incorrectly if they are not being supervised properly. Good day. you should check that any diverters, dampers, etc. The product is settling on the lines. If you are having any failures in the bags or difficulty cleaning the dust off you might want to consider other fabrics like PTFE membrane or fabrics like polypropylene that have better resistance to high moisture gas streams. Can you provide us with a better description of your process and the baghouse specs?