Thermal Deoiler Replaces Liquid Degreasing Line for Large Air Conditioning Manufacturer
Executive Summary
Epcon replaced a solvent-/water-based degreasing line for a major air-conditioning (AC) coil manufacturer with a custom thermal-deoiling + thermal-oxidizer + heat-recovery system. The new system uses dry, heated air (no water, no solvents) to remove oil and lubricant residues, combusts the released vapors safely, and recovers heat — eliminating wastewater, chemical handling and disposal, reducing environmental impact, slashing operating costs, and delivering a sustainable, efficient cleaning solution that matches prior production throughput.
Project Overview
- The customer had been dea- oiling evaporator fins and other coil components in a conveyorized solvent-based vapor degreasing line.
- Rising regulatory pressure from environmental agency (on water pollution and air-emission) forced shutdown of the solvent/water degreasing system. The company needed a waterless & solventless alternative — but one that matched the existing line’s throughput, parts-carrier configuration, and production capacity.
- Epcon was contracted to design, fabricate, and install a turnkey thermal deoiler system to fully replace the old degreasing line, enabling the customer to stay in production without regulatory interruption.
The Challenge
- Regulatory and environmental compliance: The old solvent- or aqueous-based degreasing generated hazardous waste, significant wastewater, and air emissions — increasingly unacceptable under stricter environmental regulation.
- High operational, disposal & maintenance costs: The chemical purchase, storage, handling, disposal, wastewater treatment, and associated administrative/ regulatory burden proved very costly.
- Maintain throughput and part-carrier compatibility: Replacement had to provide same production speed, part-carrier geometry, and cleaning quality to avoid disrupting coil manufacturing, brazing or further processing.
- Ensure clean, dry parts suitable for downstream processes (e.g. brazing, coating): Solvent residues or water remnants could impair finishing or bonding, so the cleaning method had to deliver dry, contaminant-free parts.
The Solution
Epcon delivered a fully engineered and integrated Thermal Deoiler + Thermal Oxidizer + Heat Recovery system — tailored to meet these requirements:
- Thermal Deoiler (dry-air, indirect-heating): The system uses heated dry air (no solvents, no water) to volatilize oils and lubricants from metal parts. This removes the need for chemical solvents or aqueous cleaning altogether.
- Thermal Oxidizer (TOX / RTO) to combust oil vapors: The volatilized oil vapors are routed to a thermal oxidizer, where they are combusted at ~ 1,500 °F with sufficient residence time (~1.0 second) — achieving a vapor destruction removal efficiency (DRE) > 95%.
- Heat recovery via stainless-steel shell-and-tube heat exchangers: Two exhaust-side heat exchangers are used — the primary pre-heats ambient air for the deoiler chamber, and a secondary raises exhaust vapor temperature before destruction, improving overall thermal efficiency and reducing additional fuel demand.
- Indirect heating to avoid condensation / part contamination: Because parts are not sprayed or immersed, and heating is indirect, there’s no risk of water or oil-vapor condensation on parts — ensuring they exit clean and dry, ready for brazing/coating.
- Turnkey replacement of degreasing line: Epcon configured the new system to match the former solvent line — same throughput, parts-carrier layout, and production workflow — to allow a smooth swap with minimal disruption.
Technical Specifications (Representative / Project-Based)
Cleaning Method: Thermal Deoiling — indirect-heated, dry-air cleaning (no water, no solvents)
Emission Control / VOC Removal: Thermal Oxidizer (1,500 °F; 1.0 s residence time) with > 95% DRE for oil vapors / VOCs
Heat Recovery: Shell-and-tube heat exchangers (primary + secondary) on oxidizer exhaust — for pre-heating deoiler air and raising exhaust temperature before combustion, maximizing energy reuse.
Part Cleanliness / Output State: Clean and dry parts after deoiling — no solvent or water residue, suitable for brazing/coating/finishing processes
Environmental / Waste Reduction: Zero chemical waste, no wastewater, no hazardous-solvent disposal; significantly reduced air pollution / fugitive emissions.
Operational Compatibility: Designed to match the previous solvent-based degreasing line’s part-carriers and throughput — enabling plug-and-play replacement without production loss.
The Results
After commissioning, the customer observed:
- Elimination of solvent/water use and hazardous waste: The solvent- or aqueous-based degreasing line was replaced — transport, storage, handling, disposal of chemicals and wastewater are no longer needed.
- Dramatic operating cost reduction: Operating costs dropped from millions per year (chemicals, disposal, wastewater treatment) to “thousands per year” — fuel costs for the thermal system.
- Reduced environmental impact and improved regulatory compliance: VOC emissions are combusted and treated; no wastewater is discharged; fugitive emissions are eliminated.
- Improved workplace safety and industrial hygiene: No handling of hazardous solvents, no chemical storage; risk to personnel and environment reduced significantly.
- Clean, dry parts ready for downstream processing: Output parts are free from solvents, moisture or residues — ideal for brazing, coating, plating or finishing — improving product quality and reliability.
- Seamless transition / minimal production disruption: Because the system was designed as a one-to-one replacement (same carriers, throughput), the manufacturing line continued operation without capacity loss.
