Waste Heat Recovery Equipment for Lithium Battery Production Exhaust Gas

Waste Heat Recovery Equipment for Lithium Battery Production Exhaust

Waste heat recovery equipment for lithium battery production exhaust refers to systems designed to recover thermal energy from exhaust gases generated during high-temperature processes such as electrode baking, sealing of electrolyte filling ports, and formation.

Lithium battery exhaust differs significantly from conventional industrial exhaust, exhibiting the following key characteristics:

Complex composition with high safety risks:

Organic solvents: N-methylpyrrolidone, dimethyl carbonate, etc., which are flammable and explosive.

Electrolyte vapors: Highly combustible when exposed to open flames or intense heat.

Potential toxicity: Contains toxic components such as fluorides.

This necessitates equipment meeting stringent safety standards to prevent any potential leaks, sparks, or hot spots.

High Corrosivity:

Under high temperatures and moisture, fluorides hydrolyze to form hydrofluoric acid—an extremely corrosive acid that severely attacks common metals.

Prone to Blockage:

Organic solvent vapors in exhaust gases condense into liquids or form viscous aerosols when cooled, readily adhering to heat exchange surfaces. When mixed with dust, this causes severe blockages.

Significant Temperature Fluctuations:

Processes do not operate at constant temperatures. Exhaust gas temperature and flow rate may vary with production cycles, requiring equipment with excellent adaptability.

Heat Pipe Heat Exchanger

Working Principle: Utilizes phase-change heat transfer within a sealed vacuum tube. The hot end absorbs waste heat from exhaust gases, while the cold end releases heat to fresh air or water.

Absolute Safety: Cold and hot fluids are completely isolated by the tube wall, fundamentally eliminating cross-contamination and risks. Even if a single heat pipe fails, it results in only a single-point failure without causing medium mixing.

Corrosion Resistance: The evaporation section (exhaust gas side) of the heat pipe can be made of high-grade stainless steel (e.g., 316L) or corrosion-resistant alloys, and even undergo surface treatments (e.g., aluminizing, spraying) to resist corrosion from HF and other substances.

Anti-clogging: The exhaust gas side can be designed with large-channel, smooth-tube structures to minimize adhesion points. Additionally, uniform heat pipe wall temperatures help reduce localized condensation.

High Efficiency & Compactness: High heat transfer efficiency and compact structure facilitate installation in existing facilities.

Recovered heat is primarily utilized for:

Preheating Fresh Air: Returning heat to the supply air systems of coating, baking, and similar equipment. This is the most direct and cost-effective method, significantly reducing energy consumption in drying processes.

Process Hot Water: Heating water required for cleaning battery casings, electrode sheets, and other components.

Workshop Heating: Providing heat to production workshops during winter.

Boiler Feedwater Preheating: Preheating cold water entering the boiler.