Explosion venting

[omidmcdonald]

I'm in the process of building a new distillery in Ontario, Canada and the issue of explosion venting has come up.  Has anyone encountered this before? Any guidance would be appreciated.

[Glenlyon]

Are they talking about just keeping the air clean of explosive concentrations or actually directing the explosion somewhere?

Directing an actual explosion sounds complex. We agreed to build a fire/explosion proof wall between the tasting area and the production area. The idea being that in the event of a blast, the customers would have time to flee. The district people didn't seem to care much about the fate of the poor distiller - although, we did wind up build in some extra egress doors - just in case.

Ethanol is a 'temporary explosion' - my favorite phrase. Temporary? But, that's how its classified. In Canada anyway.

Having worked in the gas business for a long time - in the end - concentration is what you are looking out for - which, if your equipment is running properly and under supervision you shouldn't be having a problem with. If you are - you have to revise your approach - after all, you want those fumes in the bottle, not the atmosphere.  

[et1883]

On 10/19/2017 at 7:02 PM, omidmcdonald said:

I'm in the process of building a new distillery in Ontario, Canada and the issue of explosion venting has come up.  Has anyone encountered this before? Any guidance would be appreciated.

explosions will result from sufficient concentration of ethanol vapor, so air circulation is important to reduce concentration; consider monitors to detect ethanol concentration.  Here is a 2012 discussion on monitors.  . 

 

[omidmcdonald]

Thanks for the feedback. What the inspector wants to know is how much ethanol vapor could be released by a still column if a sight glass or valve broke.  They are concerned about the possibility of this released vapor being ignited before it dissipates by ventilation.  Is there a method of estimating the amount of ethanol vapor in the column (we have a 450mm diameter, 5M tall 19 plate column on a 650L Carl pot)?

[Still_Holler]

I'm no expert and live in an area where code enforcement is basically non existent.  That being said, we purchased a gas detection unit from RKI instruments which is set for the lower explosive limit of ethanol vapor.  There is an exhaust fan mounted behind the still which is wired to the gas detector.  If the LEL is reached an alarm sounds and the exhuast fan kicks on, theoretically reducing the ethanol concentration.  It hasn't triggered yet and hopefully never will.  Good luck!

 

[Southernhighlander]

Still_Holler, Is your exhaust fan explosion proof?

[Tom Lenerz]

1 hour ago, Still_Holler said:

I'm no expert and live in an area where code enforcement is basically non existent.  That being said, we purchased a gas detection unit from RKI instruments which is set for the lower explosive limit of ethanol vapor.  There is an exhaust fan mounted behind the still which is wired to the gas detector.  If the LEL is reached an alarm sounds and the exhuast fan kicks on, theoretically reducing the ethanol concentration.  It hasn't triggered yet and hopefully never will.  Good luck!

 

If you hit the LEL you will already know you have a problem as the discomfort from vapor in the air will make it painful to breath.

We have our alarm set to 1% which you should still be able to notice, but earlier detection and notification is always best.

[Still_Holler]

Thanks Tom!

[Still_Holler]

1 hour ago, Southernhighlander said:

Still_Holler, Is your exhaust fan explosion proof?

Yes, here is the fan model

https://www.northerntool.com/shop/tools/product_200461050_200461050?cm_mmc=housefile-_-recd-_-phone-_-conf

 

[Brian]

FIRE PROTECTION DOCUMENT----

DISCUS has an Industry based document that may be applicable in Canada.  I would STRONGLY suggest you pay the nominal fee and get this publication.

"Recommended Fire Protection Practices for Distilled Spirits Beverage Facilities 3rd Edition"

Elsewhere in this forum lurk PE's who are familiar with the safety requirements and have successfully guided folks over this hurdle.

Excised from the DISCUS document....to wet you whistle...

4-7 ALARM SYSTEMS AND WATCH
SERVICE
4-7.1 Fire and evacuation alarm systems should
be considered for each facility. Operations
involve the production and handling of
flammable alcohol along with utilization and
storage of other combustible materials. These
alarm systems will help with timely
identification and notification of potential fire or
other emergencies and will facilitate a quicker
response by both private and public emergency
services (fire, police, etc.). These systems also
provide a mechanism to notify all personnel of
the need to evacuate the buildings or area.
Building, fire, or life safety codes or fire
authorities may mandate installation of these
systems. Refer to NFPA 72, National Fire
Alarm Code and NFPA 101, Life Safety Code.
4-7.2 Proper installation of fire alarm system
components, such as automatic fire detectors
(smoke, heat, optical, etc.), manual activation
devices, waterflow switches, alarm notification
appliances, control panels etc., is critical to their
satisfactory operation. Installation, testing and
acceptance of the components and systems
should conform to industry standards and
practices. Refer to NFPA 72, National Fire
Alarm Code and NFPA 101, Life Safety Code.
4-7.3 All fire alarm system wiring, initiating
devices, detectors, alarm appliances, etc., should
be listed for use in accordance with the
classification of the area in which they are
installed. Refer to NFPA 72, National Fire
Alarm Code and NFPA 70, National Electric
Code. Refer to Chapter 6.
4-7.4 Monitoring (supervision) of the fire