Reactor jackets heated by stored hot water
How a speciality chemical plant can heat its batch reactor jackets at 40–120 °C with heat pump hot water, against a furnace-oil fired thermic fluid heater.
▶Video: Heat pumps for pharma, chemicals and FMCG
V04 · 2–2.5 minJacketed reactors, hot loops, cleanroom reheat and solvent recovery
Video coming soon01Problem statement
- Thermic fluid is too hot for many steps. Most reactions run at 40 to 110 °C, but the heater supplies fluid at much higher temperature, so jackets are throttled and heat is lost.
- Thermal shock on glass-lined vessels. Hot fluid on a cooler vessel can exceed the safe wall temperature difference and damage the glass lining.
- Heating and cooling on one jacket. Switching a jacket between thermic fluid and cooling water risks mixing media and needs long purges.
- Losses between fuel and process. Burning furnace oil in a boiler or heater and distributing the heat loses a quarter or more of the fuel's energy before it reaches the process.
- Compliance, safety and handling. Fired equipment brings boiler inspections, fuel storage and unloading, flue emissions and an attendant on every shift.
02Use case
The reference plant runs four 5 KL glass-lined and stainless steel reactors making intermediates and speciality chemicals. It completes about six batches a day on three shifts.
| Heat user | Process temp. | Basis | Heat, kWh/day |
|---|---|---|---|
| Batch charge heat-up | 30 → 90 °C | 6 batches × 4,000 L, cp 2.2 kJ/kg·K, density 0.9 kg/L | 792 |
| Reaction hold | 60–110 °C | 4 reactors × 6 kW jacket and vent losses × 16 h | 384 |
| Vessel heat-up | 30 → 90 °C | 6 batches × 3,500 kg steel × 0.5 kJ/kg·K × 60 K | 175 |
| Storage and pipework standing losses | – | about 5% | 68 |
| Total useful heat | 1,419 | ||
Averaged over 20 running hours, the heat pumps need about 71 kW.
03P&ID
Tags: HP heat pump, TK tank, SG steam generator, P pump, PHE plate heat exchanger, TCV temperature control valve, TIC temperature indicating controller (panel), TT temperature transmitter, MT moisture transmitter, PT pressure transmitter, LT level transmitter, FS flow switch, NC normally closed. Process fluids are heated through their own exchanger, coil or jacket.
04Solution
System description
- A SE-UHT air-source cascade, R245fa machine of about 75 kW, air-source cascade to 120 °C, sized per project.
- A 2,500 L insulated storage tank decouples the heat pumps from the process peaks.
- The furnace-oil fired thermic fluid heater stays connected behind a normally closed valve as standby.
- The heat pumps charge a pressurised tank at up to 120 °C, which serves reactor jackets through a secondary loop.
- Each reactor has a jacket temperature control unit that mixes loop water to the recipe temperature and limits the jacket-to-mass difference.
- Steps that need more than 110 °C in the mass stay on the existing thermic fluid supply.
Selected equipment
| Machine | SE-UHT air-source cascade, R245fa |
|---|---|
| Capacity | about 75 kW, built to duty |
| Concept | air-source cascade to 120 °C, sized per project |
| COP used | 1.6 (estimate) |
| Supply temperature | 120 °C |
| Storage | 2,500 L insulated tank |
Capacity is sized from the heat demand above. COP is an estimate until Sunniva engineering confirms the design.
Control philosophy
TT-101 starts the heat pumps below 110 °C and stops them at 120 °C, with TT-102 staging the second unit. TIC-201 and TIC-202 control jacket inlet temperature in cascade with the reactor mass temperature and enforce a maximum jacket-to-mass difference. The thermic fluid heater stays connected as standby.
05Energy saving and ROI
Change any input to match a customer's site. Defaults are typical Indian prices for October 2026. The installed cost is a placeholder; replace it with the actual quotation.
| Existing | Heat pump | |
|---|---|---|
| Daily consumption | – | – |
| Annual energy cost | – | – |
| Cost per batch | – | – |
| CO₂ per year | – | – |
06Benefits
Safer for glass-lined vessels
Hot water at a controlled temperature keeps wall temperature differences inside the lining limits.
Simpler jacket service
Water-based heating and cooling share one medium, so there is no thermic fluid to purge.
Closer temperature control
Mixed hot water lets the jacket follow the recipe ramp smoothly.
Lower energy cost
Each kWh of electricity delivers about 1.6 kWh of heat at the required temperature, against well under one kWh of useful heat per kWh of fuel burnt.
No flame on site
No burner, flue or fuel tank for this duty, and no fuel deliveries to schedule.
Solar-ready
Running hours can be placed in daylight so rooftop solar supplies much of the electricity, which also cuts CO₂ further.
07Engineering pointers
Site data to collect
- Reactor sizes, materials and jacket ratings
- Batch recipes with temperature steps
- Batches per day and cycle times
- Thermic fluid heater fuel use
- Area classification of the reactor bay
- Present fuel or electricity use and monthly bill
- Sanctioned electrical load and spare capacity
- Space for the heat pumps and storage, with service access
- Winter minimum ambient at site
Design notes
- Pressurised loop. Water up to 120 °C needs a closed loop at 3 bar or more. Check jacket design pressures before connecting.
- Hazardous area. Reactor bays are usually classified. Keep the heat pumps and tank in a safe area and bring only water into the plant.
- Exotherms. Exothermic reactions need full cooling capacity on demand. Make sure switching from hot water to cooling water is fast and fail-safe.
- Ambient correction. Ratings are at 20 °C air. Ask Sunniva for the correction at your site's winter design temperature.
- Water quality. Scale forms quickly above 60 °C. Use softened make-up and keep the heat pump loop closed, with process fluids on the far side of an exchanger or coil.
- Performance figure. The COP on this page is an engineering estimate, not a data sheet value. Sunniva engineering will confirm it for the actual source and supply temperatures.
Service and warranty
Sunniva has supplied 5,000+ heat pumps since 2012, with nine service technicians across India, including remote sites such as Leh. All components carry a one-year warranty.
Talk to us
Reactor jackets heated by stored hot water
How a speciality chemical plant can heat its batch reactor jackets at 40–120 °C with heat pump hot water, against a furnace-oil fired thermic fluid heater.
▶Video: Heat pumps for pharma, chemicals and FMCG
V04 · 2–2.5 minJacketed reactors, hot loops, cleanroom reheat and solvent recovery
Video coming soon01Problem statement
- Thermic fluid is too hot for many steps. Most reactions run at 40 to 110 °C, but the heater supplies fluid at much higher temperature, so jackets are throttled and heat is lost.
- Thermal shock on glass-lined vessels. Hot fluid on a cooler vessel can exceed the safe wall temperature difference and damage the glass lining.
- Heating and cooling on one jacket. Switching a jacket between thermic fluid and cooling water risks mixing media and needs long purges.
- Losses between fuel and process. Burning furnace oil in a boiler or heater and distributing the heat loses a quarter or more of the fuel's energy before it reaches the process.
- Compliance, safety and handling. Fired equipment brings boiler inspections, fuel storage and unloading, flue emissions and an attendant on every shift.
02Use case
The reference plant runs four 5 KL glass-lined and stainless steel reactors making intermediates and speciality chemicals. It completes about six batches a day on three shifts.
| Heat user | Process temp. | Basis | Heat, kWh/day |
|---|---|---|---|
| Batch charge heat-up | 30 → 90 °C | 6 batches × 4,000 L, cp 2.2 kJ/kg·K, density 0.9 kg/L | 792 |
| Reaction hold | 60–110 °C | 4 reactors × 6 kW jacket and vent losses × 16 h | 384 |
| Vessel heat-up | 30 → 90 °C | 6 batches × 3,500 kg steel × 0.5 kJ/kg·K × 60 K | 175 |
| Storage and pipework standing losses | – | about 5% | 68 |
| Total useful heat | 1,419 | ||
Averaged over 20 running hours, the heat pumps need about 71 kW.
03P&ID
Tags: HP heat pump, TK tank, SG steam generator, P pump, PHE plate heat exchanger, TCV temperature control valve, TIC temperature indicating controller (panel), TT temperature transmitter, MT moisture transmitter, PT pressure transmitter, LT level transmitter, FS flow switch, NC normally closed. Process fluids are heated through their own exchanger, coil or jacket.
04Solution
System description
- A SE-UHT air-source cascade, R245fa machine of about 75 kW, air-source cascade to 120 °C, sized per project.
- A 2,500 L insulated storage tank decouples the heat pumps from the process peaks.
- The furnace-oil fired thermic fluid heater stays connected behind a normally closed valve as standby.
- The heat pumps charge a pressurised tank at up to 120 °C, which serves reactor jackets through a secondary loop.
- Each reactor has a jacket temperature control unit that mixes loop water to the recipe temperature and limits the jacket-to-mass difference.
- Steps that need more than 110 °C in the mass stay on the existing thermic fluid supply.
Selected equipment
| Machine | SE-UHT air-source cascade, R245fa |
|---|---|
| Capacity | about 75 kW, built to duty |
| Concept | air-source cascade to 120 °C, sized per project |
| COP used | 1.6 (estimate) |
| Supply temperature | 120 °C |
| Storage | 2,500 L insulated tank |
Capacity is sized from the heat demand above. COP is an estimate until Sunniva engineering confirms the design.
Control philosophy
TT-101 starts the heat pumps below 110 °C and stops them at 120 °C, with TT-102 staging the second unit. TIC-201 and TIC-202 control jacket inlet temperature in cascade with the reactor mass temperature and enforce a maximum jacket-to-mass difference. The thermic fluid heater stays connected as standby.
05Energy saving and ROI
Change any input to match a customer's site. Defaults are typical Indian prices for October 2026. The installed cost is a placeholder; replace it with the actual quotation.
| Existing | Heat pump | |
|---|---|---|
| Daily consumption | – | – |
| Annual energy cost | – | – |
| Cost per batch | – | – |
| CO₂ per year | – | – |
06Benefits
Safer for glass-lined vessels
Hot water at a controlled temperature keeps wall temperature differences inside the lining limits.
Simpler jacket service
Water-based heating and cooling share one medium, so there is no thermic fluid to purge.
Closer temperature control
Mixed hot water lets the jacket follow the recipe ramp smoothly.
Lower energy cost
Each kWh of electricity delivers about 1.6 kWh of heat at the required temperature, against well under one kWh of useful heat per kWh of fuel burnt.
No flame on site
No burner, flue or fuel tank for this duty, and no fuel deliveries to schedule.
Solar-ready
Running hours can be placed in daylight so rooftop solar supplies much of the electricity, which also cuts CO₂ further.
07Engineering pointers
Site data to collect
- Reactor sizes, materials and jacket ratings
- Batch recipes with temperature steps
- Batches per day and cycle times
- Thermic fluid heater fuel use
- Area classification of the reactor bay
- Present fuel or electricity use and monthly bill
- Sanctioned electrical load and spare capacity
- Space for the heat pumps and storage, with service access
- Winter minimum ambient at site
Design notes
- Pressurised loop. Water up to 120 °C needs a closed loop at 3 bar or more. Check jacket design pressures before connecting.
- Hazardous area. Reactor bays are usually classified. Keep the heat pumps and tank in a safe area and bring only water into the plant.
- Exotherms. Exothermic reactions need full cooling capacity on demand. Make sure switching from hot water to cooling water is fast and fail-safe.
- Ambient correction. Ratings are at 20 °C air. Ask Sunniva for the correction at your site's winter design temperature.
- Water quality. Scale forms quickly above 60 °C. Use softened make-up and keep the heat pump loop closed, with process fluids on the far side of an exchanger or coil.
- Performance figure. The COP on this page is an engineering estimate, not a data sheet value. Sunniva engineering will confirm it for the actual source and supply temperatures.
Service and warranty
Sunniva has supplied 5,000+ heat pumps since 2012, with nine service technicians across India, including remote sites such as Leh. All components carry a one-year warranty.