Health and Safety for Beginners Forums

Hi All
Just after somones knowledge if poss....... I work for a waste management company and we dry waste before it goes to shredding for waste to energy. However, we have had historical issues of fire within drying bins, the causes are unknown but assumptions are that it maybe lithium ion batteries or even aerosols, again there is no solid evidence, nothing is ever found and fires are very small that we deal with them on site. do we need to complete a DSEAR assessment?

Hi Pete,

Could you say what waste you are drying and how it is dried?
If you could detail the drying process it would help to give advise.

When i read it i assumed you would be drying paper, cardboard maybe wood.
Then you mention about lithium batteries and aerosols

Cheers

Glen

Hi Glen.
The waste is general, plastic, wood, paper, card etc collected from commercial business. it arrives on site, shredded, then is sent through a trammel so that fine material is extracted, then onto a sorting line where wood, hard plastic, card is removed, metal is removed via a magnet and the rest is loading into a drying bin. sometimes metal is not picked up by the magnet and therefore ends up inside the drying bin hence why I mention the batteries and aerosols, the heat is approximately 60 Celsius and is monitored, the bins usually stay there for 24 hrs. although we have only had one small fire as a result, there was no clear indication of the cause, it may have just been "one of them" situations where it got too hot, but I have to assume it could have been or the hazard remains that we may end up with aerosols or lithium batteries inside.

Thanks
Pete

It sounds to me that further investigation needs to made into how the fire started before you can make any decisions. If your thoughts prove correct, it may be that you need to improve the system to keep lithium batteries and aerosol cans away from the drying unit and heat more than you need a DSEAR assessment.

I would also be uneasy receiving shredded combustible waste that may contain batteries in the first place, let alone putting them through a process. Is it shredded in the delivery lorry/skip or before loading?

I assume others in the recycling business use this system, maybe use identical kit. I would start there and ask them (even competitors) or their experiences.

Unfortunately we have no or little control on what people put into the waste, we send regular reminders out regarding the batteries and aerosols, but without having hundreds of people searching the waste like a police investigation line, this would be impracticable let alone very costly. The control we have in place is that we have a magnet to retrieve the metal and in all fairness it does do the job unless the metal object is under a heavy item. The other measures are that the temperature is controlled and the drying times are controlled, I am looking now at a fire suppression system over the drying bins to prevent the spread of fire.
The DSEAR assessment needs to be done on the assumption of the risk, not on the actual occurrence.

Thanks

HI Pete,

As Messy said, i too would be concerned with the source of the fire before fitting a suppression system.

The likeness that springs to mind is with noise and wearing hearing protection first as oppossed to reducing or removing the noise.
Im not saying a suppression system would not help, but as a company owner and in charge of QEHS i would want to know the source then look at control measures to prevent reoccurance.

All that being said i dont work in your industry, just applying the thought process from what i know.

Pete B wrote: ↑Tue Jun 19, 2018 4:26 pm Hi Glen.
The waste is general, plastic, wood, paper, card etc collected from commercial business. it arrives on site, shredded, then is sent through a trammel so that fine material is extracted, then onto a sorting line where wood, hard plastic, card is removed, metal is removed via a magnet and the rest is loading into a drying bin. sometimes metal is not picked up by the magnet and therefore ends up inside the drying bin hence why I mention the batteries and aerosols, the heat is approximately 60 Celsius and is monitored, the bins usually stay there for 24 hrs. although we have only had one small fire as a result, there was no clear indication of the cause, it may have just been "one of them" situations where it got too hot, but I have to assume it could have been or the hazard remains that we may end up with aerosols or lithium batteries inside.
Thanks
Pete

If wood, hard plastic and card is removed by hand, most metal via a magnet what materials end up in the drying bins?
Also what about non magnetic metals like aluminium, copper, tin, brass etc? Are these extracted somehow or do they end up in the drying bins?

Regards

Glen

Not in the frame of mind to write loads as I'm using my phone not a PC but I wholly agree with the previous comments and questions.
The statements about the sorting process don't add up and I wouldn't be happy with not improving the process before paying out for a suppression system.
Making an assumption that the cause is batteries or aerosols without evidence is not acceptable in my book.
Smacks of solutionising on guesswork, not problem resolving.

Hi Pete

Have you investigated the phenomenon of auto-combustion? Many items as they dry can generate a fair bit of heat which can lead to things catching fire. As the son of a farmer we have always been told that you do not put wet hay in the barn as it can catch fire.

https://www.fwi.co.uk/business/wet-weat ... re-warning

On my site we have shot blasting plant, the fine dust that is left over will again catch fire if it gets wet, i have seen old dust filters which have not been disposed of correctly slowly burst into flame.

As you have paper and other fine materials this may be something you should look at, if it is wet and slowly heating up it may be the cause of your problem. When you move these items are there any indicators of heat such as steam or are items warm?

Have any similar business or your trade organisation come across this problem, might be worth asking the question.

Regards

QS

Hi Yes I agree with what you are saying as I am from a farming background, the problem I have is within the sortation process, only large items are identified by operatives, small Lithium batteries will filter through the sieving process and not reach the sortation operatives, slightly larger ones will generally be caught up in the shredder and will not reach the sieving process and have been known to catch fire. Fires are more common in the summer periods, having only been in the waste industry for 3 months, I'm seeing that disposable BBQ's are a major hazard if they are disposed of prior to cooling.
The company works with a consultancy service who attend once a month, they have requested a DSEAR assessment is completed, my argument is that how can you assess something on an assumption with no evidence? surely I need to know what exactly I'm dealing with?

Pete