Author Topic: Oxy reduct  (Read 7944 times)

Offline shaunmckeever

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Oxy reduct
« on: May 25, 2007, 11:04:32 AM »
I am intending to advise the use of oxy reduct on a large warehouse. Is anyone aware of any significant drawbacks?

Offline kurnal

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Oxy reduct
« Reply #1 on: May 25, 2007, 12:03:44 PM »
How can you control the environment in such a large space? The loading docks will be open to the atmosphere much of the time, the large building will be subject to huge wind pressures, I think it would be impossible to achieve.

Offline Ashley Wood

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Oxy reduct
« Reply #2 on: May 25, 2007, 12:56:29 PM »
Hi Shaun,

I have a similar problem with a vast archive store where they are moving a lot of air in and out. I have asked Wagner to come up with a solution but I to do not know how they can maintain an inert atmosphere when you have so many air changes. I can see the problem with a warehouse as Kurnal says. I can see a problem at the top of the building where the Oxygen concentration may be higher in the inert atmosphere, this may be a problem where high bay racking is used. However, I do know that it has been done before, so it must work (I think!). On the side effects, I have been told by a number of people that prolonged working may be an issue in an oxygen reduced environment, 4 or 6 hours max was a figure that seems to spring to mind.

Best regards

Ashley

Offline shaunmckeever

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Oxy reduct
« Reply #3 on: May 25, 2007, 01:32:54 PM »
Kurnal we have raised this with Wagner but they have assured us that an inert atmosphere can be maintained. In fact they say that is easier to achieve in a large warehouse than in a smaller environment. I can see that if the large doors are going to be held open then it will be difficult to maintain the Oxygen level at 15%-17%. The warehouse will be for long term storage and should  not have the doors open regularly.

Ashley I am informed that work can be undertaken within the reduced oxygen atmosphere but duration I believe is limited to a maximum of 4 hours. How people perform in an oxygen reduced atmosphere is another question. The reason why oxy reduct is being considered for the warehouse (high bay rack storage) is because there will not be anyone working for long periods.

I am interested in your comment about having areas where oxygen is likely to gather i.e. at the top of the warehouse. Is this what happens, do the gases separate?

I do have concerns because Wagner have said that the the notrogen is introduced at low level around the inside perimeter of the building. In a high bay warhouse I wonder how the centre of the warehosue is covered.

We are meeting with Wagner next week to address some of these concerns and I am grateful for any issues that haven't been thought about to be flagged up here before we go.

Thanks
Shaun

Chris Houston

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Oxy reduct
« Reply #4 on: May 25, 2007, 03:26:50 PM »
Issues will be in there are contents in the warehouse that are unexpected.  Will the sytem be capable of preventing a fire if there are aerosols, petrol, or other unexpected items.

Resolvable issues with humans working in reduced oxygen environment.

Issues if insurers are wary about accepting such a system given the lack of UK accreditation.

Issues if the system fails, unlikely that this may be.

Chris Houston

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Oxy reduct
« Reply #5 on: May 25, 2007, 03:27:26 PM »
See other thread on issue that was (wrongly) in Q n A but is now moved.

Offline Ashley Wood

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Oxy reduct
« Reply #6 on: May 30, 2007, 05:09:43 PM »
Shaun,

Remember when you calculate for a gas system we would take the height of the highest cabinet in an IT room as the critical height, and this was the height at which the gas had to hold for 15-20 mins. Now, I am probably looking at this in a simplistic way but if say the highest rack was at 8 meters with light fittings at 9 meters then the inert atmosphere should be no lower than 9 meters, say in a 10 meter high warehouse. If it is not then you could end up with O2 at normal concentrations above say 6 meters. This would leave 4 meters of the warehouse and 2 meters of rack and 1 meter of lights unprotected! Does that make sense? So, if they are pumping in at low level how do they guarantee a reduced O2 level from slab to apex? Are they pressurising the building to a high degree?