How one company turned emissions into free fuel
Lasco Bathware found free fuel as part of MACT compliance in this What Works case study.
For years, fiberglass-reinforced baths and showers have been perceived as commodity products. Of course, as with any product, there have always been quality differences between brands. Nevertheless, the manufacturing methods employed and the materials used have been roughly similar.
That’s all changed. As of April 21, 2006, manufacturers of reinforced plastic composites are required to meet the U.S. Environmental Protection Agency’s hazardous air pollutant emissions regulations under new maximum achievable control technology (MACT) standards
MACT requires plastic composite manufacturers to either install new controls, or compromise formulations by reducing styrene levels. Styrene is used for two purposes: as an agent for spraying and as a cross-linking agent, which gives hardness and rigidity to items such as bathtubs.
Styrene, an essential component of fiberglass reinforcement technology, is released into the air during the manufacturing process. While health and environmental concerns haven’t been confirmed (styrene quickly breaks down in the atmosphere), the EPA’s precautionary measures now require manufacturers to capture and control 95% of styrene emissions.
To comply with the new MACT standards, a plastics composites manufacturer has several options:
- Ignore regulations and face fines and possible plant closures.
- Reduce the amount of styrene used in production, typically resulting in a weaker product.
- Use lower emitting, less effective resins. This option generally requires more reinforcing material.
- Invest in pollution control technologies that capture and eliminate styrene emissions. This option allows a manufacturer to continue to build products using the most effective and strongest material formulation.
Lasco Bathware (www.lascobathware.com) has invested more than $20 million to make MACT-compliant capital improvements and renovate its manufacturing plants. This investment provides several distinct competitive advantages.
- Lasco’s investment of more than $2 million in each of its eight U.S. manufacturing plants means the company not only meets new clean air standards, it exceeds them.
- Lasco’s response allows the company to use the optimum styrene formulation in its fiberglass reinforcement process, resulting in strength, durability and overall quality of its products.
- By gathering styrene and burning it in a thermal oxidizer, Lasco has reduced styrene emissions by approximately 250,000 tons per year. Using the captured and incinerated styrene as a fuel, Lasco also has reduced its dependence on other energy sources, saving an average of $400,000 per year per plant based on a full production schedule and 2006 energy rates.
For this project, the Environmental and Energy Systems division of Dürr Systems (www.durr.com/en) installed a Disc Concentrator System. The system includes a rotary concentrator with a rotary-valve regenerative thermal oxidizer (RTO). The rotary concentrator, which features a proprietary material supplied by Dürr’s exclusive supplier, doesn’t allow styrene to polymerize on its surface. Dürr was able to guarantee a five-year life for this material. “We wanted a five-year guarantee on the absorbent and that came with the contract,” notes Syd Pe, Lasco project manager.
A high-efficiency filter was installed upstream to remove any particulate matter in the airstream. By using the concentrator system, the net cost increase was approximately $2 per product unit, a significantly lower cost compared to the alternatives considered. Because Lasco produces more than a million units per year, this represented a significant savings.
The fuel economy the Disc Concentrator System provides proved to be a major factor in the final selection decision. “Because of the fuel economy, we were able to increase airflow in the plants without increasing fuel consumption,” Pe says. “We haven’t had much experience with these types of systems and felt that Dürr’s size and expertise afforded us the security we were looking for.”
The system operates without any natural gas consumption. The concentrator removes the styrene from the air stream, concentrates it more than 10 times, then feeds it into the RTO for destruction. This provides enough energy to sustain the RTO’s operation without the addition of any external fuel.
“A competitor proposed a less efficient oxidizer, a recuperative system, but there was an extremely high fuel consumption for the unit,” says Jason Valia, Dürr Systems regional sales manager, “So short-term, ours wasn’t the absolute lowest cost. But long-term, ours definitely will be. Overall, the cost of ownership was much lower than the systems offered by other companies.”