Air Pollution Control - Bag Filters

You sell the bags? What are they made of? What service have they been in?

If they are all going to land fill, then the tough questions are justifiable. It would be a Good Thing to have a disposal strategy to hand, the justification for which effort is "stay in business".

PWSlack I know they are justifiable. But solution is a must for this.

So give the forum something to use, then.

Are there places that recycle clothes? Most these places go thru them pick out the clothes that can be used. Either sell them or donate them. Those clothes that are beyond being used are bundled and sold to make felt. Those bags can be used to make felt. Address it with one of those companies.

• One of the approaches is to reduce or eliminate the dust problem, so that the bags are not needed. As there are significant operational advantages in so doing, this has to be the preferred approach.
• Another is to use separation technologies that eliminate the bag; there is a popular brand of domestic vacuum cleaner in the UK that uses cyclones to separate the dust rather than a bag, for example. The technology is making significant headway on market share against the more familiar brand that was originally invented in the USA.
• Etc., etc.

Dear PWSlack,

1:Reducing the dust problem would not be possible in reality especially in the cement industry where there productivity is completely dependent on the proper working of the APC.

2: This is an industrial application and not domestic. SO vacuum cleaner will be of no use.

Then the Customer is faced either with continuing to landfill, or with returning the bags to the supplier for reprocessing.

At this moment, the forum knows nothing about the number of bags, their weight, their materials-of-construction, and all those other good things that constitute the foundations for an engineered solution. Until some hard data is forthcoming, WAGs will be...

Dear PWSlack,

Yes that is the situation, the customer is left to continue landfill. The second option can be thought about. I will discuss it with the Filter Bag suppliers as to how they can use them for reprocessing.

As far as weight is considered, it ranges from 400-725 gms.

Moc can be Polyester,Polypropylene,Ryton,Fibre Glass,etc.

The basic reason why i posted this query was how can we take into consideration various MOC of the filter bags and design a system in which all of these different MOC's can be processed to generate some energy or any other substitute with additions of some catalyst which help them to break down.

Cyclones not just used for domestic vacuums.

Most of which will remove 99% of the dust.

dear ozzb,

yes cyclones are used for industrial purposes but the size of the dust which it filters is very high. It can't filter fine dust. This is normally used before Bag Filter so that bag Filter does not get choked due to heavy dust.

Bag Filter can filter upto 5-10 mg of dust.

no one knows? I HIGHLY doubt that

Dear Fredski,

Even i am amused as no one knows. Google is something where you get everything. I asked it a simple question of how to dispose/recycle filter bag after use? it could not give me even one proper link where any information could be gathered.

your bag manufacturer would be well versed on the topic

I wouldn't have put up the question here if that was the case. This is still a unknown thing and the world is just pilling up the land fill.

Burn them, then. Use them as fuel.

And please stop countering contributors' suggestions with reasons for not doing that thing. Otherwise this thread will go nowhere. Once all the options are in the open, choose the least-worst one.

You might try a pilot project for washable or cleanable filters....here are some suggestions....

http://www.epa.gov/ttncatc1/dir1/cs6ch1.pdf

Suggest to your customers that they find a source for bag filters who has adequate knowledge of waste disposal to help them, or hire an environmental specialist to advise you and your customers.

Dear Lyn,

Yes the next option is to take an advise from en environment specialist.

Letting cement loose in the environment is even worse. The bags containing cement must be disposed of at a authorized disposal site . Contact the environmental department of your country they most probably have regulations in place.

You may find that those bags are made of Nomex so that they can withstand the high heat from your kilns. Nomex is considered non-hazardous waste so it can safely go into the waste stream, but it also won't break down after years of burial.

Why not try washing the bags and reusing them, just remember to treat the effluent from your washer, maybe the recovered fines can be used in your concrete mixture. There may be a personnel protective equipment manufacturer in your area that can use the bags as cloth for their clothing. Looks like new fabric costs around 15USD per yard.

Very stylish too....

You do not provide much information as to size or composition but after reading all the replies up to this time it appears that you have a bag house to collect the dust from the cement process. At the steel mill I worked in our bags were about 12-15 inches in diameter and 15 feet long. When new they were quite attractive and appeared to be a nylon or similar product. I do not know if kevlar was produced at that time. I do believe that they could be washed and sold for some income as there is a considerable amount of material in each bag. More information is needed as to material and dimensions but recycling is a definite possible.

Remove more of the dust from the filters so that the bags last longer. In filter bag houses they use a reverse blast of air projected into the clean side of the bag to remove dust from the outside and have it fall down to the bottom of the bag house where it eventually collected and disposed of. This makes the bags last longer thereby reducing the number of bags used per length of time.

Another method is to choose the materials that the bags are made of so that they can be burned with the dust still on them. If the temperature of the burn is correct for the material of construction, the bags will burn and only the ashes and the dust remain. This way the ashes of the bags are disposed of with the dust.

Both these methods are used extensively in the precious metals processing and the chemical industries. With the precious metals the bags are loaded up into the next melt batch. The bags burn away and the metal dust is reprocessed into ingots or other forms. The ashes from the bags are removed with the slag.

Good Luck, Old Salt

That's potentially a goodgreat solution. However, as yours is the 21st comment and OP has not seen fit to answer the basic questions I posed in the 1st comment, we're all wasting our time here (more so than usual ). To be completely fair, OP did PM me this, "We make system and sell the smart parts also within the system." I did't think it added any value, so I didn't mention it earlier.

bigg-

Thanks, a lot of good solutions go unrecognized and not used or even acknowledged by OP's. Simply letting the contributor know that you have at least read it helps everyone. The more contributions acknowledged the more people are motivated to contribute and contribute good answers. Doesn't matter how short or long it is, just how applicable to the question and given in a manner that is clear to the OP.

These solutions are a clear and sensible answers to the problem stated. They are two that time has certainly proven to be very successful. Millions of dollars in investment sure shows it works. It's his loss not mine or yours!

Again, thank you for your reply. Hopefully others will see it and be motivated to give good and workable solutions. Most contributors don't sit in front of a keyboard on this forum simply for the fun of it. They want to help another with their problem.

Good Luck, Old Salt

Dear all contributors,

I appreciate your contribution on the question posted. Just wanted to let u guys know that, on the day I posted the query i had joined the community so i am still new to this and hence i haven't been active and didnt reply to your suggestions. Apologize for that!

Dear bigg,

I PM you because that was a personal question of selling bags. Anyways probably you took it in the wrong sense.

Thank you Old Salt. Will take into consideration your suggestion and try and apply in working.

old salt,

the second option is widely followed in Indian Cement industry as most of the used bags are put inside the cement kilns. but the environment department advise them to refrain from doing land fill due to it's long decomposing time.

However they say it affects their intermediate product and hence need some alternate solution.

Many power plants are adding bag houses in addition to the currently installed Electrostatic Precipitators to remove Mercury. MATS

Even though the Hg concentrations are measured in nano grams, I'm sure after a bag is ready for disposal, no one will want to recycle it unless they documented the hq content of the bag.

http://www.powermag.com/enhanced-capture-of-mercury-using-unique-baghouse-filter-media/

http://www.epa.gov/airmarkets/progsregs/epa-ipm/docs/append5_3.pdf

For disposing the filter bags you should suggest people to contact local municipal, as they have special air pollution control units under environmental remediation, they have special chemical bags in which they keep such bags and then dispose them together. They can collect in bulk if you ask them.