Case Study: Printed Circuit Board Emissions

Industry

Electronics / Semiconductor

Problem

One of the world's largest printed circuit board (PCB) manufacturers was required to install air pollution abatement equipment to control the VOCs emitted during their soldering and coating process. Three main considerations were important to the customer:

• The need for a system with a competitive capital cost and the lowest possible operating cost
  
• The ability to engineer a system that did not affect the sensitive production process
  
• The necessity to install a compliant system as quickly as possible
  

Action

After a detailed technical evaluation, the company selected Anguil Environmental Systems, Inc. to solve their VOC emissions problem and to place them in compliance. Anguil installed a Model 200 Regenerative Catalytic Oxidation (RCO) system that meets all applicable regulatory requirements and offers significant operating cost savings.

Solution

One advantage of Anguil's application-specific method is that it provides the customer with the most effective solution for their particular needs. After studying this customer's PCB production process and associated emissions, Anguil recommended the unique solution of a 20,000 SCFM/32,000 Nm3/h Regenerative Catalytic Oxidizer (RCO).

Regenerative catalytic oxidation offers a blend of two proven emission control technologies to provide the lowest operating costs for the customer. Catalytic oxidation has been an effective VOC control technology for many years; it was developed to oxidize VOCs at low temperatures and to reduce the high operating costs of direct-flame thermal oxidation. Regenerative thermal oxidation has been used frequently in the past decade; it is designed to capture the energy released during oxidation to reduce operating costs. Regenerative catalytic oxidation combines these two technologies to further optimize fuel effieciency.

In the Anguil Twin Bed Regenerative Catalytic Oxidizer, the VOC-laden process exhaust is heated as it passes through the first ceramic media bed located in an energy recovery chamber. The process air moves from this energy recovery chamber into the catalytic combustion chamber, where the VOCs are then oxidized, releasing heat energy into a second recovery chamber. A flow-control valve switches the airflow direction so that energy transfer to the ceramic media in both energy recovery beds are fully utilized, thereby reducing any auxiliary fuel requirement. This system is designed for a heat recovery of over 95% and is self-sustaining, requiring no added auxiliary fuel even with low VOC loadings. This efficient energy recovery means the Anguil RCO has significantly lower operating costs than other emission treatment methods.

Many factors are involved in designing a system that maintains low operating costs. For this customer, high auxiliary fuel (natural gas) costs made the extremely low fuel consumption of the RCO an appealing option. The addition of a catalyst in the RCO reaction chamber lowers the VOC destruction temperature and allows for operation with lower fuel consumption than a Regenerative Thermal Oxidation systems. Anguil provided operating cost calculations demonstrating that the fuel savings of the RCO would provide a full recovery of the catalyst cost in less than twelve months of operation.

The next design consideration was the engineering of a system that did not effect the PCB production process. PCB manufacturing, like many other Electronics industry applications, requires carefully controlled environments. It is essential that a pollution control system does not exert significant back-pressure on the finely balanced production process and adversely affect the final PCB product. To ensure production quality, Anguil designed the RCO with a unique flow-control valving arrangement that prevented any back-pressure from altering the exhaust airflow from the manufacturing process.

The final project consideration was satisfying the customer's stringent time frame. From the outset, Anguil worked with the customer to develop a detailed project management schedule. Anguil's complete turnkey installation of the RCO provided single source responsibility; the pre-assembled, pre-wired, and pre-tested system was installed by Anguil's experienced installation team. The rapid integration of the system into the plant's operations meant minimal downtime and ensured proven emission compliance.

The system is operating and providing VOC destruction efficiency well above required levels. Once again, Anguil's engineering expertise, innovative technology solutions and turnkey capabilities resulted in a satisfied customer.