Industrial Explosion Protection ATEX Technologies Overview

Industrial Explosion Protection ATEX Technologies Overview

Summary

Commonly begins with the ignition of a fuel that burns very rapidly.

Produces a large and sudden release of gas

An explosion need not involve a fire.

When a container bursts from increased internal pressure, sudden release also called an explosion

Industrial Explosion ProtectionATEX Technologies Overview
Characteristics of An Explosion

Commonly begins with the ignition of a fuel that burns very rapidly.

Produces a large and sudden release of gas

An explosion need not involve a fire.

When a container bursts from increased internal pressure, sudden release also called an explosion.

Explosion Pentagon 

Combustible Dust (Fuel
Oxygen (Air
Ignition Source (electrostatic discharge, electric current arc, glowing ember, hot surface, welding slag, frictional heat or flame)
Dust Suspension in air exceeding the MEC 
Confinement (vessel, room, building, ductwork
Secondary Explosions

Secondary dust explosions, due to inadequate housekeeping and excessive dust accumulations.

Secondary dust explosions due to propagation through interconnected ducts, chutes, conveyors, …etc.

SECONDARY EXPLOSIONS ARE THE MAIN THREAT TO PERSONNEL AND PROPERTY!


Deflagration Principle 

Flame Speed 30 ft/s

30 ft/s (9m/s)

Pressure Wave 1100 ft/s

1100 ft/s (335 m/s)

Industries At Risk 

Chemical 

Petrochemical 

Grain 

Food 

Pharmaceutical 

Aerosol 

Steel 

Cement 

Wood 

Food Manufacturing Industries 
Starch Manufacturing and Handling 
Cereal Plants 
Breweries 
Sugar Refining 
Dairy Products 
Chocolate Manufacturing 
Food Flavorings and Additives 
Dairy 
Starch Manufacturing, Mixing/Handling 

Ingredion (National Starch)

MGP Ingredients
Cargill
Grain Processing Corp.
ADM
Tate & Lyle

Firmenich 

Givaudan Roure

Cereal Plants 
Kelloggs
Kraft/Post Foods
Ralston Purina
Quaker Oats
Chocolate/Candy Mfgs.

Nestles
Hersheys
M&M Mars
Just Born

Malt Plants 
Breweries 
Anheuser-Busch
Labatts
Coors
Rolling Rock

Food Additives 

Solae Company

International Flavors and Fragrances

Sugar Western SugarAmerican SugarsImperial SugarsAmerican Crystal Sugars,Dairy Products (powder) Kraft FoodsAC HumcoNestles

Dairy Farmers of America,Others, including:Cake mix plantsFood thickenersContract mixing/packagingFlour milling
Grain Handling                     Pharmaceutical Manufacturing 
ADM                                          Pill Manufacturers
                                                   •Powder Manufacturing/Handling
                                                   •Pill Coaters
Cargill
Bunge
Harvest States
Central Soya
The Andersons
Chemical Manufacturing 
Plastics - ABS, Phenolic Resins
Polyethylene
Acrylics
Methylcellulose
Pigments, Dyes
Epoxies
Fertilizers, Herbicides, Pesticides
Ink Toners
Stearates
Equipment At Risk :

Dust Collectors    Reactors 

Bins, Hoppers, Silos

Pneumatic Conveying

Mechanical Conveying

Cyclones

Dryers (Spray, Fluid Bed, Rotary) 

Mixers, Blenders

Mills, Grinders, Pulverizers 

Deflagration Pressure vs. Time

Deflagration Classification:

ST Classification:ST-1, ST-2, ST-3;     Rst Value:1-200;201-300,301-above
Example:
Pittsburgh seam coal has a Kst of 129 bar-m/sec,making it an ST-1 dust        Applicable Codes (USA)

§NFPA 654  Combustible Particulate Solids
§NFPA 664  Wood Processing
§NFPA 61  Agricultural and Food Products
§NFPA 484  Metal Dusts
§NFPA 30B   Aerosol Products
§NFPA 68  Venting of Deflagrations
§NFPA 69  Explosion Prevention Systems

§NFPA 652   Fundamentals of Combustible Dust
Technologies Explosion Protection
Technologies Explosion Protection
Deflagration Suppression 
Deflagration Relief Venting 
oStandard
oFlameless 
Deflagration Isolation 
oActive
oPassive