Automatic emergency valve closers on chlorine tonners 1

[5wp]

Hi:
I'm looking for a proven product that can do the following with five chlorine tonners.
1.Close automatically in the event of a chlorine leak.
2.Fail in the safe mode, ie valve closed, not open.
3.Be independent of plant line power.
4.Operate every time, or at least keep trying to operate
untill closed.
5.Open or close tonner valves as required.
We have tried out the Halogen system but there are several things that can go wrong, from module failure to a low battery. Hardly what you want to have to deal with with a chlorine leak.
Any help or direction would be appreciated.

 

[reena1957]

Instead of gaseous chlorine, try a chlorine releasing liquid product compatible with the system into which chlorine is going. Sodium hypo chlorite soluion is one that comes to mind. Many installations are switching to such measures due to safety/reliability problems of chlorine gas! best wishes

 

[JimCasey]

There are several manufacturers out there who make very good gas monitors, MSA leaps immediately to mind. Scott is another. Most any of them have SPDT relay output. Wire a solenoid-piloted valve through the Normally OPEN contacts on the monitor. These contacts will be closed when everything is copacetic. THe solenoid will get power, admit air to the (spring-closed)actuator, and the valve will open. If you have a gas alarm, power loss, or air loss, the valve snaps closed. Use a ball valve of the appropriate size and material (monel or titanium ball)cleaned for Chlorine, with a relief hole drilled into the upstream side of the ball. Just for kicks, unless the valves cycle periodically,throw a timer relay into the circuit so it opens the circuit for a few seconds every week or so, and the valve won't be stuck open when you really need it.

 

[5wp]

I agree liquid chlorine is safer, but there are other problems that I never mentioned that would make liquid a rather difficult go.
Thanks for that suggestion.

 

[5wp]

Jim when you say solenoid-piloted valve you are not referring to the one that comes with the tonner, or the valve on the header, but to one on the line that
would allow Cl2 to proceed to the injector?
I'm looking for a device that will close down the existing valve that comes with the toner, as supplied by the vendor. I guess the logic here is that if you can close the valve at the tonner, you stop any chances of Cl2 getting in from other tonners by backfeeding thru the header. This can however take a bit of torque to close. So if this device fails to close the valve in an emergency it is no longer a fail safe device.
What we are presently using has a bit of electronics with a battery power source, etc. The old story, the more complex the more chances of failing.
However I see your idea of using the monitor to trigger the line closed.
Thanks again

 

[abcmex]

5wp,
If you are handling chlorine one major source of information is the Chlorine Institute (

http://www.chlorineisntitute.org).

They have an specific document handling this CI Publication "RECOMMENDATIONS FOR EMERGENCY CLOSURE DEVICES FOR CONTAINER VALVES". Perhaps interesting for you:

http://www.chlorineinstitute.org/fi...fetyProductStewardshipBulletin-1withChart.pdf

Regarding the closing devices for ton containers, there are some supplier like:

http://www.robo-control.com/Spec-2000C.asp

. Search the Internet and you will find more.

rgs

rgs.

 

[JimCasey]

5wp: What I had in mind was a spring failsafe, pneumatic actuator. Let the air out, it closes. If you contact a reputable actuation house, the first thing they will ask you is how much torque the valve requires. Then they will ask a lot of questions about how frequently the actuator operates, whether the service is dry/slurry/lubricating, etc., and how fast you need the valve to close. For a critical application they will supply an actuator with a substantial safety factor in its torque rating. Then you will need to worry about getting them the dimensions of all the parameters necessary to mount the actuator, but a large actuation house may already have your valve(s) on file.

 

[5wp]

Thanks for all the replys on this subject.I guess I'll do more research on whats available that would put our concerns to rest.
Thanks again.

 

[dcasto]

There are also hydraulic actuartors that keep a supply of hydraulic pressure that will allow operation in the event of a loss of power.

 

[ferclor]

We have the product you are looking for:

Please visit

http://www.powellfab.com/products/ValveClosure.asp

you will find all the responses there, please contact me at lfvivas@powellfab.com