Thermal Deoiler Reduces Wastewater for AC Manufacturer
Executive Summary
Executive Summary
Epcon replaced a water- and solvent-based degreasing line for an air-conditioning (AC) coil manufacturer with a custom thermal deoiling + thermal oxidizer + heat-recovery system. By shifting to a dry-air, indirect-heating cleaning process, the customer eliminated hundreds of millions of gallons of wastewater, removed toxic cleaning chemicals from their process, cut disposal costs dramatically, and achieved a sustainable, compliant, and fuel-efficient solution — delivering long-term environmental and economic benefits.
Project Overview
The customer — a major AC / HVAC-coil manufacturer — previously used chemical spray/dip degreasing (including chlorinated solvents such as tetrachloroethane) to clean oil and lubricant residues from aluminum fins and other coil components prior to brazing or assembly. Regulatory bans on these solvents (and tightened wastewater-disposal rules) forced the customer to rethink its cleaning method.
Epcon proposed and supplied a turnkey thermal deoiling system, integrated with a thermal oxidizer and heat recovery units, to replace the chemical-wash line. The deoiler uses indirectly heated dry air (no water, no solvents) to clean parts; oil vapors are combusted in the oxidizer, generating clean, dry heat that is reused — ensuring the parts are clean and dry, without wastewater discharge or hazardous chemical use.
The Challenge
Key challenges that drove the need for a new solution:
- Regulatory ban: After the prohibition of tetrachloroethane (and similar solvents), the customer could no longer rely on conventional solvent-based degreasing.
- Water & wastewater disposal: Traditional aqueous cleaning lines generate large volumes of contaminated wastewater requiring treatment or disposal — costly and environmentally burdensome.
- Toxicity & environmental impact of chemicals: Use of hazardous solvents and surfactants posed health, environmental, and compliance risks.
- Need for a clean, dry, solvent-free part cleaning process: Coil components needed to be free of oil/lubricant residues and moisture before brazing, welding, or further processing — without introducing new contaminants or using hazardous materials.
- Desire for energy efficiency and sustainable operation: Rather than simply switching solvents or cleaning methods, the customer preferred a future-proof, environmentally friendly cleaning solution that also minimized energy and disposal costs.
The Solution Delivered by Epcon
Epcon supplied a fully integrated Thermal Deoiler + Thermal Oxidizer + Heat-Recovery system, delivering:
- Indirect-heating thermal deoiler: Dry hot air (no water, no solvents) is used to volatilize oil/lubricant residues from coil components. The clean, dry process leaves parts ready for brazing/coating without residual moisture or contaminants. Thermal deoiling is a well-established, chemical-free cleaning technology.
- Thermal oxidizer (TOX / RTO) to combust vaporized oil: The deoiler exhaust — containing oil vapors — is routed to a thermal oxidizer, where vapors are destroyed (converted to CO₂ and H₂O), eliminating VOC emissions and environmental hazard from the cleaning process.
- Heat-recovery system: The heat generated by the oxidizer is recovered and used to reheat the deoiling chamber (or for other plant purposes), significantly reducing additional fuel/energy consumption; leveraging oil-vapor combustion as part of the heat source. This makes the system far more energy-efficient than conventional ovens or cleaning lines.
- Elimination of wastewater and toxic chemicals: Because cleaning is done with dry air and no solvents/water, there is no wastewater to treat or dispose — removing a major environmental and regulatory burden for the customer.
Turnkey delivery: Epcon engineered, fabricated, installed, and commissioned the full system — oven/deoiler + oxidizer + heat recovery + controls — simplifying integration for the customer and ensuring compliance with environmental/industrial standards.
Technical Specifications
Cleaning Method: Thermal Deoiling: indirect-heated dry air to remove oil/lubricant residues from metal parts (AC coils / fins) — no water or solvents used.
Emission Control: Thermal Oxidizer to combust oil vapors / VOCs released during deoiling — ensures safe, clean exhaust and environmental compliance.
Heat Recovery: Recovered combustion heat used to pre-heat deoiler or plant air — significantly reducing additional energy/fuel demand.
Wastewater / Chemical Use: Zero wastewater discharge; no use of toxic cleaning chemicals — reducing chemical waste, disposal cost, and environmental impact.
Operational Impact: Eliminates the need for dip-wash / solvent-based cleaning lines — simplifying workflow and reducing regulatory risk.
Environmental & Regulatory Benefits: Compliant with modern environmental regulations restricting hazardous solvents / wastewater discharge; reduces VOC emissions and chemical waste.
The Results
After commissioning, the customer realized:
- Elimination of wastewater generation & chemical waste — hundreds of millions of gallons of wastewater avoided, and hazardous cleaning chemicals eliminated from process.
- Dramatic reduction in disposal and cleaning-chemical costs — disposal of wastewater and chemical-waste fees eliminated; the case study notes cost reductions of 4,000–5,000%.
- Improved sustainability and environmental compliance — switching to a dry, solvent-free process reduces environmental footprint, avoiding water contamination and emissions associated with solvent use and wastewater treatment.
- Energy and fuel efficiency — by recovering heat from the oxidizer, the deoiler operates much more efficiently than a conventional oven or combustion-based cleaning system, lowering fuel costs and improving overall process efficiency.
- Simplified operations and reduced regulatory/maintenance burden — no complex wastewater treatment, chemicals, or hazardous-waste management; reduced oversight and easier compliance with environmental regulations.
- Potential throughput or capacity improvements — because the thermal deoiler avoids drying or rinse cycles associated with aqueous cleaning and eliminates downtime for wastewater treatment, manufacturing flow can be more continuous and predictable.
