Industrial powder coating made in the USA: an NFPA-compliant filtration plant

Industrial powder coating - like other energy-intensive processes that involve chemical preparations - is a particularly polluting operation that tends to generate waste substances of various nature that have to be collected and disposed of with the utmost care and attention. Overspray is a mixture of highly toxic volatile organic compounds with varying composition characteristics, and an overall incidence that depends on the transfer and adhesion efficiency of the powder paint on the surfaces to be treated. The application of powder paint can also create potentially explosive atmospheres due to electrostatic effects. In the presence of an ignition source such as a spark and/or particular environmental conditions (such as pressure and temperature variations within the booth) can result in explosions.

Fot the recent installation of a dry filtration system for a company in the USA, we received precise indications regarding the need for high-performance and reliable technologies capable of preventing the risk of accidents related to potentially explosive atmospheres on the powder coating line.

The requirements included in the customer's specifications did not only concern the supply of a filter configured for operation in an ATEX zone, but also the need for a dust recovery system and reinforced piping to connect the various filtration units. The performance requirements of the plant were the starting point to provide a complete filtration line that would guarantee compliance with the dust emission limits set by the EPA, the US Environmental Protection Agency, and also would be compliant with standards defined by official institutions and ad hoc regulations.

TAMA Aernova technologies - complete with the required custom, technical, economical and environmental documentation - were implemented on the customer's infrastructure overseas.

Located at the beginning of the filtration line, the V-Aren cyclone is designed to recover and recycle powder coating dust. V-Aren is a preventive treatment for the partial reduction of airborne pollutants and it is capable of separating and recovering over 96% of the incoming powder, exploiting the centrifugal force to which the airborne particles are subjected. The automatic sieve on the cone outlet - secured with ATEX hooks to guarantee maximum tightness even in the event of activation of the explosion suppression barrier - precedes the entry of the recovered paint powder into the bin and its re-introduction to the colour centre. 

The cyclone is followed by the Kompac Air MTJ cartridge filter equipped with pneumatic cleaning system and configured with an overhead fan and with ATEX differential pressure switch for reading and controlling the static pressure of the fan.
The control unit of the system is able to detect abnormal pressure variations inside the filter and cyclone by means of dynamic pressure sensors. If necessary, it activates the suppression tanks to protect the dust volumes and block the potential ignition of combustion and explosion. On the other hand, chemical barriers on the pipes, these controlled by the control unit too, prevent the explosion from spreading to the rest of the plant and outside it, towards the spray booth. These devices contain nitrogen and sodium bicarbonate powder: thanks to their chemical-physical properties, inhibit the reactivity of the particles and replace part of the comburent, preventing the ignition of combustion and blasting and their possible propagation in the plant.

The importance of being a supplier in compliance with US standards

All industrial and manufacturing activities producing air pollution are subject to control and validation by the public institutions, which transpose the standards issued by national and supranational governments and verify their implementation in the relevant territories.

Each Nation is required to respond to the need to reduce atmospheric emissions by applying analysis and control models. Despite a margin of variability linked to the different legal systems, in any part of the world the end customer is required to identify risks and dangers linked to dust and processes involved. The plant supplier, therefore, must draw up a coherent design that complies with local regulations, starting from this definition of risk. Hence the importance of relying on qualified and referenced companies capable of supporting and facilitating industries in defining and implementing solutions that suited to purpose.

The standards that our company guarantees for compliance with US regulations concern the supply of ATEX-certified components for the mechanical part; adherence to NFPA (National Fire Protection Agency) standards for electrical components; and the provision of explosion venting systems or the equipping of plants with fire/explosion suppression systems. In detail, TAMA Aernova supplies:

• ATEX-certified and NFPA-compliant mechanical parts 
• ASME-certified and Class II Division 2 tanks 
• electrical cables and components marked UL or CSA (or another NRTL or SCC accredited body) and in Class II Division 2 category 
• installations equipped with explosion venting systems (also flameless) with pipe-tightness check valves 
• plants equipped with FM-certified fire/explosion suppression systems and chemical barriers at pipeline partitioning 

TAMA Aernova also collaborates with recognised organisations in the USA to carry out audits and obtain certificates to simplify inspections once installation has taken place in order to speed up the issue of authorisation for commissioning by the AHJ (Authorities Having Jurisdiction). 

Every new project for TAMA Aernova is a challenge, which leads us to raise our service and expertise to even higher levels. The know-how we have acquired, the right partnerships, manufacturing capacity, and logistical organisation enable us to handle and satisfy complex requests even in seemingly distant destinations.