The problem
An East Coast label printing plant needed to upgrade its regenerative thermal oxidizer (RTO). The three-canister RTO, packed with ceramic saddles, was achieving approximately 93% thermal efficiency at 17,000 scfm — but the plant now needed to treat 24,000 scfm of VOC-laden exhaust air. Purchasing a new RTO would require significant capital expenditure.
MLM-200 replaced an 8′6″ saddle bed with 3′8″ of structured media — and delivered higher thermal efficiency at 41% greater throughput than the original RTO was designed for.
Why MLM-200 was selected
The alternatives were a new RTO or a retrofit of the existing equipment with multi-layer media (MLM) from Lantec Products. To avoid a major capital outlay, the decision was made to retrofit the system with MLM-200.
MLM-200's structured geometry delivers dramatically lower pressure drop than random saddles while maintaining superior heat transfer per unit of bed depth — which is why the same canister volume can be served by a significantly shorter bed.
Meeting the requirements
In early June 1998, the 8′6″ bed of 1″ saddles in each heat-recovery canister was replaced with 3′8″ of MLM-200. The results met all expectations.
During continuous operation at superficial gas velocities exceeding 375 scfm/ft², thermal efficiency improved to 94.6% — higher than the pre-retrofit figure of 93% with saddles — while overall pressure drop was reduced. All applicable emission standards were met throughout.
The RTO now operates at 24,000 scfm. The MLM-200 bed is designed to accommodate future expansion up to 28,000 scfm without further media changes.
