Ceramic Media Upgrade for Automotive Paint Line
Proper RTO ceramic media bed design for an automotive manufacturer's spray booth emissions helped this customer greatly reduce plugging issues from their siloxane solids.
Problem
Emissions from a Tier 1 automotive paint line were plugging the ceramic media beds in a 25,000 scfm regenerative thermal oxidizer (RTO). Frequent and costly ceramic media cleanings and replacements were harming production schedules and profitability. Paint emissions containing siloxanes were the source of the plugging. When the siloxanes are exposed to the high temperatures in an RTO ceramic media bed they form SiO₂ which adheres to the ceramic media surface. Over time, the particulate will fill what is referred to as the ‘void volume’ of the media and begin to plug the bed leading to increased pressure drop throughout the unit. To maintain the desired airflow draw from the spray booths the RTO fan speed increases to overcome the additional system airflow resistance due to plugging. The results are increased operating costs (fan horsepower) and decreased thermal efficiency (higher burner firing). Also, additional wear and tear on the RTO due to pressure spikes during valve switches.
Photos: In Progess
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Solution
Kono Kogs was hired to analyze the plugging and develop a solution to extend ceramic media life. With proper ceramic media bed design, the bed life can be extended significantly and sometimes plugging can be alleviated completely. However with siloxanes, the plugging cannot be eliminated. In these cases understanding at what temperatures the creation of solid SiO₂ occurs determines the best solution. The bed design that offers the combined longest life and highest fuel efficiency was proposed. Kono Kogs worked with local contractors hired by our customer to facilitate COVID travel/work rules in 2021. Additional plugging was found in the cold face upon removal of the ceramic media, which was unexpected. Cleaning and cold face repairs were made to allow the desired 1 day media replacement to hold schedule. Kono Kogs left an extremely clean job site, and also re-started and confirmed proper RTO operation prior to leaving.
Photos: After
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Equipment & Services Provided
- Assess media plugging characteristics
- Design media bed optimizing life and thermal efficiency
- Provide ceramic media and oversight for replacement
- Ensure clean work site before leaving
