One machine for process cooling and heating
How a bulk-drug plant can use heat pumps to cool its reactor cooling water and make 70 °C process hot water at the same time, and what it saves against a furnace-oil fired boiler.
▶Video: Heating and cooling from one machine
V11 · 2–2.5 minWater-source heat pumps that chill and heat at the same time
Video coming soon01Problem statement
- Cooling and heating in the same building. One set of utilities removes heat from reactors and condensers while another burns fuel to heat other reactors a few metres away.
- Cooling tower limits. In summer the cooling tower cannot always hold 32 °C, which slows solvent recovery and crystallisation.
- Steam for moderate temperatures. Many reactor heating steps only need 60–70 °C, yet they use steam and need careful throttling to avoid overheating.
- 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 makes active pharmaceutical ingredients in glass-lined and stainless reactors over three shifts. Reactor jackets and solvent condensers reject heat to a cooling tower circuit at 32 °C, while the same plant uses steam for reactor heating, washing and AHU reheat.
| Heat user | Process temp. | Basis | Heat, kWh/day |
|---|---|---|---|
| Reactor jacket heating | Hot water 70 °C | 3 reactors × 40 kW × 6 h | 720 |
| Equipment washing | 70 °C | 15,000 L/day, 30 → 70 °C | 697 |
| AHU reheat for clean rooms | Hot water 60–65 °C | 3 AHUs × 10 kW × 18 h | 540 |
| Storage and pipework standing losses | – | about 5% | 98 |
| Total useful heat | 2,054 | ||
Averaged over 18 running hours, the heat pumps need about 114 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 Customized water-source cascade machine of about 115 kW, two-stage water-source machine built to duty, lifting 32 °C to 75 °C.
- A 3,500 L insulated storage tank decouples the heat pumps from the process peaks.
- Heat source: reactor and condenser cooling water return at about 32 °C. Cooling the reactor cooling water to 25–27 °C relieves the cooling tower and helps solvent recovery.
- The furnace-oil fired steam boiler stays connected behind a normally closed valve as standby.
- Cooling water returning from reactor jackets and condensers at 32 °C passes through the heat pump evaporators and returns at 25–27 °C.
- The condenser side makes 70–75 °C water into a storage tank for reactor heating, washing and AHU reheat.
- The cooling tower stays in the circuit and takes any surplus heat, so process cooling is never dependent on hot water demand.
- Heat pumps are sized on the smaller of the two loads so both outputs are fully used.
Selected equipment
| Machine | Customized water-source cascade |
|---|---|
| Capacity | about 115 kW, built to duty |
| Concept | two-stage water-source machine built to duty, lifting 32 °C to 75 °C |
| COP used | 2.9 (estimate) |
| Supply temperature | 75 °C |
| Storage | 3,500 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 at the top of the tank starts the heat pumps below 68 °C and stops them at 74 °C. A temperature sensor on the cooling water supply lets the heat pumps run longer when the cooling tower cannot hold 30 °C. TIC-201 to TIC-203 control each user. Steam stays as standby for reactor heating.
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 | – | – |
| CO₂ per year | – | – |
06Benefits
Colder cooling water in summer
Cooling water leaves the heat pumps at 25–27 °C, which speeds condensation and crystallisation on hot days.
Gentle reactor heating
70 °C jacket water heats glass-lined reactors without the thermal shock risk of steam.
Two utilities from one input
Every kWh of electricity delivers both cooling and heating, so the combined efficiency is very high.
Lower energy cost
Each kWh of electricity delivers about 2.9 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
- Cooling water flow and temperatures by hour
- Reactor heating steps, temperatures and durations
- Washing and AHU reheat loads
- Steam use for these duties
- Hazardous area classification
- Present fuel or electricity use and monthly bill
- Sanctioned electrical load and spare capacity
- Space for the heat pumps and storage, with service access
Design notes
- Solvent contamination. A leaking condenser can carry solvent into the cooling water. Fit a conductivity or LEL check on the loop and keep heat pumps outside flameproof zones.
- Load matching. Log cooling and heating demand by hour. The heat pumps earn most when both loads run at the same time.
- Glass-lined reactors. Respect the vessel maker's limits on jacket-to-batch temperature difference.
- Source stream. The source must give up roughly two-thirds of the heat delivered. Confirm its flow and temperature over a full production day, and filter it before the evaporator.
- 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
One machine for process cooling and heating
How a bulk-drug plant can use heat pumps to cool its reactor cooling water and make 70 °C process hot water at the same time, and what it saves against a furnace-oil fired boiler.
▶Video: Heating and cooling from one machine
V11 · 2–2.5 minWater-source heat pumps that chill and heat at the same time
Video coming soon01Problem statement
- Cooling and heating in the same building. One set of utilities removes heat from reactors and condensers while another burns fuel to heat other reactors a few metres away.
- Cooling tower limits. In summer the cooling tower cannot always hold 32 °C, which slows solvent recovery and crystallisation.
- Steam for moderate temperatures. Many reactor heating steps only need 60–70 °C, yet they use steam and need careful throttling to avoid overheating.
- 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 makes active pharmaceutical ingredients in glass-lined and stainless reactors over three shifts. Reactor jackets and solvent condensers reject heat to a cooling tower circuit at 32 °C, while the same plant uses steam for reactor heating, washing and AHU reheat.
| Heat user | Process temp. | Basis | Heat, kWh/day |
|---|---|---|---|
| Reactor jacket heating | Hot water 70 °C | 3 reactors × 40 kW × 6 h | 720 |
| Equipment washing | 70 °C | 15,000 L/day, 30 → 70 °C | 697 |
| AHU reheat for clean rooms | Hot water 60–65 °C | 3 AHUs × 10 kW × 18 h | 540 |
| Storage and pipework standing losses | – | about 5% | 98 |
| Total useful heat | 2,054 | ||
Averaged over 18 running hours, the heat pumps need about 114 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 Customized water-source cascade machine of about 115 kW, two-stage water-source machine built to duty, lifting 32 °C to 75 °C.
- A 3,500 L insulated storage tank decouples the heat pumps from the process peaks.
- Heat source: reactor and condenser cooling water return at about 32 °C. Cooling the reactor cooling water to 25–27 °C relieves the cooling tower and helps solvent recovery.
- The furnace-oil fired steam boiler stays connected behind a normally closed valve as standby.
- Cooling water returning from reactor jackets and condensers at 32 °C passes through the heat pump evaporators and returns at 25–27 °C.
- The condenser side makes 70–75 °C water into a storage tank for reactor heating, washing and AHU reheat.
- The cooling tower stays in the circuit and takes any surplus heat, so process cooling is never dependent on hot water demand.
- Heat pumps are sized on the smaller of the two loads so both outputs are fully used.
Selected equipment
| Machine | Customized water-source cascade |
|---|---|
| Capacity | about 115 kW, built to duty |
| Concept | two-stage water-source machine built to duty, lifting 32 °C to 75 °C |
| COP used | 2.9 (estimate) |
| Supply temperature | 75 °C |
| Storage | 3,500 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 at the top of the tank starts the heat pumps below 68 °C and stops them at 74 °C. A temperature sensor on the cooling water supply lets the heat pumps run longer when the cooling tower cannot hold 30 °C. TIC-201 to TIC-203 control each user. Steam stays as standby for reactor heating.
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 | – | – |
| CO₂ per year | – | – |
06Benefits
Colder cooling water in summer
Cooling water leaves the heat pumps at 25–27 °C, which speeds condensation and crystallisation on hot days.
Gentle reactor heating
70 °C jacket water heats glass-lined reactors without the thermal shock risk of steam.
Two utilities from one input
Every kWh of electricity delivers both cooling and heating, so the combined efficiency is very high.
Lower energy cost
Each kWh of electricity delivers about 2.9 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
- Cooling water flow and temperatures by hour
- Reactor heating steps, temperatures and durations
- Washing and AHU reheat loads
- Steam use for these duties
- Hazardous area classification
- Present fuel or electricity use and monthly bill
- Sanctioned electrical load and spare capacity
- Space for the heat pumps and storage, with service access
Design notes
- Solvent contamination. A leaking condenser can carry solvent into the cooling water. Fit a conductivity or LEL check on the loop and keep heat pumps outside flameproof zones.
- Load matching. Log cooling and heating demand by hour. The heat pumps earn most when both loads run at the same time.
- Glass-lined reactors. Respect the vessel maker's limits on jacket-to-batch temperature difference.
- Source stream. The source must give up roughly two-thirds of the heat delivered. Confirm its flow and temperature over a full production day, and filter it before the evaporator.
- 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.