Power Generation Industry
This is one of the most critical applications, where reliability is paramount.
- Steam Condensers: The largest application. STHEs are used to condense the exhaust steam from a turbine back into water (condensate). This creates a vacuum that improves the turbine’s efficiency.
- Feedwater Heaters: They preheat the water (feedwater) before it enters the boiler. Using steam extracted from the turbine, they significantly improve the plant’s thermal efficiency.
- Oil Coolers: Cool the lubricating oil used in large turbines, generators, and pumps.
2. Oil, Gas, and Petrochemical Refineries
Refineries are perhaps the largest users of STHEs, with hundreds of units on a single site.
- Crude Oil Cooling: Cooling crude oil after distillation and other processing steps.
- Product Cooling/Heating: Heating or cooling various process streams like naphtha, kerosene, diesel, and heavy gas oils.
- Reboilers: Used as the heat source for distillation columns to vaporize the bottom product. Specific types like kettle reboilers and thermosyphon reboilers are Shell and Tube variants.
- Condensers: Condensing overhead vapors from distillation columns.
- Charge Heaters: Preheating the crude oil feed before it enters the distillation column.
3. Chemical and Process Industries
Similar to refineries, they are used for a multitude of temperature control tasks.
- Process Heating/Cooling: Precise temperature control of chemical reactants and products is essential for reaction rates, safety, and product quality.
- Solvent Condensation: Recovering solvents from vapor streams.
- Waste Heat Recovery: Capturing heat from a hot process stream to preheat a colder stream, dramatically improving energy efficiency and reducing fuel costs.
4. HVAC & Refrigeration
- Chillers: Acting as the evaporator or condenser in large central chilling plants for district cooling or large buildings.
- District Heating: Transferring heat from a central plant (e.g., a power station) to water that is circulated to heat buildings.
5. Marine Industry
- Central Cooler / Jacket Water Cooler: Cooling the closed-loop fresh water that cools the ship’s main engine.
- Lubricating Oil Cooler: Maintaining the temperature of the engine’s lube oil.
- Fuel Oil Heater: Heating heavy fuel oil to reduce its viscosity for easier pumping and atomization before combustion.
6. Other Key Applications
- Compressor Aftercoolers: Cooling air after compression, which reduces its volume and removes moisture.
- Food and Beverage Processing: Used in processes like pasteurization, sterilization, and cooking (e.g., heating milk, sugar solutions, or cooking oils). They must often be made of stainless steel to meet hygiene standards.
- Pharmaceutical Industry: For similar heating/cooling applications under strict hygienic (often sanitary) conditions.
- Pulp and Paper Industry: Heating chemical solutions used in the pulping process and recovering heat from waste streams.
Applications by Function
| Function | Industry Example | How it’s Used |
| Condensation | Power Generation, Refineries | Condensing turbine exhaust steam or distillation column vapors. |
| Cooling | All Industries | Cooling process fluids, products, lubricants, or compressed air. |
| Heating | Refineries, Chemical Plants | Preheating feed streams or process fluids. |
| Evaporation | Chemical Plants, Refineries | Reboilers vaporize the bottom product of a distillation column. |
| Heat Recovery | All Industries | Capturing waste heat from one stream to heat another, saving energy. |
| Phase Change | HVAC | Acting as an evaporator or condenser in a refrigeration cycle. |