Detonation occurs as a result of a combination of such components under certain parameters:
- Oxygen;
- Combustible dust;
- Confined space inside equipment;
- Ignition source;
- Explosive concentration of dust-air mixture.
Explosion protection of bucket elevators
Aligning with MS GOST, ATEX, NFPA standards
Reducing risks and preventing losses from dust explosion
Approval of the explosion protection project with supervisory authoritiesWhy is it important for you to have a reliable explosion protection system for bucket elevator?
Noria (closed-type vertical bucket conveyer), depending on the size and speed of the conveyor, is capable to transport thousands of tons of free-flowing materials per day. Even the most reliable bucket elevator design and its regular maintenance do not guarantee uninterrupted operation of the system. There is a risk that cannot be avoided.
Explosion!
The destruction of the bucket elevator is not only a stop in production and a violation of delivery dates. These are irreparable losses of products and a threat to the life and health of personnel.
Free-flowing materials are subjected to friction during movement inside the elevator. As a result, combustible dust is formed, which, when suspended, forms an explosive atmosphere. So, for example, 40 g/m3 of its concentration in the air is enough to ignite grain dust.
How can an ignition source appear in closed bucket elevator housing?
According to EN 1127-1, these sources can be:
- heated surfaces,
- mechanical sparks,
- electrical equipment,
- static electricity,
- lightning,
- electromagnetic waves.
The temperature in the area of the running chain drive motor reaches high values. Even the hardly visible fire scale in a dusty environment can lead to a devastating explosion in closed elevator housing.
HOW TO PROTECT THE BUCKET ELEVATOR FROM THE EXPLOSION?
Knowing the design of the elevator, the type of free-flowing material, the conditions for the explosion occurrence and characteristics of its behaviour, it is possible to develop a safe solution to protect the bucket elevator from destruction.
Explosion hazard and explosion protection parameters:
- LEL – lowest concentration of dust (g/m3) at which an explosion can occur.
- UEL – highest concentration of dust (g/m3) at which an explosion cannot occur;
- P max – maximum overpressure (bar) in the vessel as a result of the explosion;
- P red – residual pressure (bar) inside the equipment after explosion venting or explosion suppression;
- P stat – pressure (bar), at which the explosion venting device opens
K st – rate of explosion pressure rise within 1 m3 of space in 1 second
(bar/m/s)
Potentially explosive areas are assessed
according to EN 60079-10-2
HOW TO PREVENT DAMAGE?
This is possible with the use of ELEVEX protection system from the Czech manufacturer RSBP spol. s.r.o. and its official representative – ATEX.CENTER.
«We design effective explosion protection systems for bucket elevators based on current international standards and knowledge of the specifics of the development and propagation of dust-air mixtures’ explosions.»
ATEX.CENTER Engineer
Vitalii Tkachuk
HOW THE ELEVEX IS DESIGNED?
ELEVEX is a system of devices for explosion detection, suppression and safely venting of destructive energy outside the bucket elevator. It consists of three effective solutions, each of which can be used both separately and in combination with others.
The current legislation in the field of production and labour protection requires the ensuring of necessary safety of bucket elevators during its construction.
Each of the solutions is offered in strict accordance with the standards:
- Explosion venting devices EN 14797:2017
- Explosion isolation systems EN 15089:2017
- Explosion isolation systems EN 16447:2017
- Explosion suppression systems EN 14373:2017
- Flameless explosion venting EN 16009:2017
EXPLOSION PROTECTION SOLUTIONS
After assessing the explosion hazard of the aspiration system and analyzing all the risks in production, we develop possible solutions for explosion protection.
№1 Bursting metal venting panels VMP
HOW DOES THIS WORK?
With the overpressure of the explosion, the panel ruptures, venting the flame outside the bucket elevator into a safe area in open space.
SPECIAL FEATURES
- Instant response when the pressure exceeds 0.05 bar;
- Low cost and easy installation;
- Equipped with an opening sensor;
- Equipped with thermal insulation (optionally)
№2 Flameless explosion venting devices FLEX
HOW DOES THIS WORK?
Flameless explosion venting devices FLEX, located outside the bucket elevator, are installed complete with VMP venting panels and prevent the flameout. When triggered, the vented explosion products pass through a mesh system at the dissipative surface, as a result of which the pressure and temperature are reduced to a safe level.
SPECIAL FEATURES:
- Possibility of installation in closed-type bucket elevators;
- Providing a safe area for people and production;
- High system reliability;
- Low maintenance costs
№3 HRD-system
HOW DOES THIS WORK?
The optical and pressure sensors detect the emerging explosion and transmit a signal to the control unit. The control unit processes it and sends an activation signal to the HRD containers located in the columns, bucket tipping devices and boots of the bucket elevator to disperse a powder mixture that effectively suppresses the flame.
SPECIAL FEATURES
- Lowering the explosion pressure to safe levels;
- Availability of installation and replacement of used kit;
- Equipment with optical sensors and pressure sensors;
- Environmentally friendly explosion suppression mixture
Why is it worth to install ELEVEX for explosion protection of bucket elevators at ATEX.CENTER?
1. You will be confident on the explosion safety of your production. The ELEVEX system has been tested by experienced specialists from RSBP spol. s.r.o. and ATEX.CENTER engineers.
2. The ELEVEX system fully complies with the requirements of international labour protection legislation and explosion protection standards for enterprises. ATEX.CENTER certified specialists will assess the explosion hazard of a bucket elevator and select an effective solution for its explosion protection in strict accordance with the standards.
3. All service documentation for explosion protection of bucket elevators is adapted for local markets. ATEX.CENTER provides full service support according to the manufacturer's standards.
The ELEVEX system reduces the pressure of the explosion to a safe level and provides avoiding damaging effects on the equipment. ELEVEX components take into account all the factors that may be the causes of an explosion in a bucket elevator and provide comprehensive reliable protection of the elevator from an explosion.
WE WILL ASSESS THE RISKS, MAKE THE NECESSARY CALCULATIONS AND SELECT AN INDIVIDUAL TURNKEY SOLUTION FOR THE EXPLOSION PROTECTION OF YOUR BUCKET ELEVATOR.
