Hot-fill heating from cooling-tunnel heat
How a sauce and juice plant hot-filling about 34 tonnes a day can heat its product with a heat pump that recovers heat from its own bottle cooling tunnel, instead of a diesel boiler.
▶Video: Waste-heat recovery heat pumps
V10 · 2–2.5 minLifting warm water from condensers, effluent and process cooling to useful heat
Video coming soon01Problem statement
- Heat in, heat out. Product is heated to 92 °C for filling and then cooled straight back down in the tunnel. The tunnel heat goes to a cooling tower.
- Viscous product, tight temperature. Ketchup must leave the heater at a steady 88–92 °C. Too cold risks spoilage and too hot darkens colour.
- Tunnel cooling is slow in summer. Warm cooling-tower water lengthens the tunnel and limits line speed on hot days.
- Losses between fuel and process. Burning diesel 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 ketchup, sauces and fruit juice in glass and PET bottles over two shifts. Product is heated to about 92 °C in a tubular heater, filled hot, inverted, and cooled in a multi-zone spray tunnel. About 24 tonnes of ketchup and sauces and 10,000 litres of juice are filled a day.
| Heat user | Process temp. | Basis | Heat, kWh/day |
|---|---|---|---|
| Ketchup and sauce heater | 50 → 92 °C | 24 t/day (22,000 L at 1.1 kg/L), 10% losses | 1,118 |
| Juice hot-fill heater | 75 → 90 °C | 10,000 L/day after regeneration | 166 |
| Storage and pipework standing losses | – | about 5% | 64 |
| Total useful heat | 1,349 | ||
Averaged over 16 running hours, the heat pumps need about 84 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
- 4 × SE-WWUHT-27 (108 kW total) (SE-WWUHT water-source, R245fa) delivering 105 °C, covering the day's 1,349 kWh in about 12.5 running hours.
- A 3,500 L insulated storage tank decouples the heat pumps from the process peaks.
- Heat source: cooling-tunnel return water at about 50 °C. Cooling the tunnel water cuts cooling tower load and speeds bottle cooling.
- The diesel-fired steam boiler stays connected behind a normally closed valve as standby.
- The warm zones of the cooling tunnel return water at about 50 °C. This feeds the water-source heat pump, which makes hot water at about 105 °C.
- The tubular heater for sauces and the juice heater both run on this hot water, replacing steam.
- The tunnel water comes back from the heat pump cooler, so bottles cool faster in the first zones.
Selected equipment
| Model | SE-WWUHT-27 × 4 |
|---|---|
| Heating capacity | 27 kW each, 108 kW total |
| COP | 2.6 estimated for a 50 °C source (the data sheet is rated on a 60/55 °C source) |
| Rating | water or steam to 120 °C, R245fa |
| Supply temperature | 105 °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 tank top starts the heat pump below 100 °C and stops it at 105 °C. TIC-201 holds sauce at the filler at 92 °C. TIC-202 holds juice at 90 °C. If the tank falls below 96 °C, the existing steam heater is enabled 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 tonne of product | – | – |
| CO₂ per year | – | – |
06Benefits
Tunnel heat reused
The heat that cooling the bottles used to waste now heats the next product.
Faster cooling
Colder tunnel water shortens cooling time, which can help line speed in summer.
Even fill temperature
Hot water at a controlled temperature keeps viscous sauce at a steady fill temperature.
Lower energy cost
Each kWh of electricity delivers about 2.6 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.
Built-in redundancy
Several machines share the load. If one is serviced, the others and the storage carry most of the day, with the existing heater in reserve.
07Engineering pointers
Site data to collect
- Products, fill temperatures and daily volumes
- Product temperature before heating
- Tunnel zone temperatures and flow
- Existing heater type and steam use
- Line speed and running hours
- 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
- Tunnel water quality. Tunnel spray water picks up product and label debris. Fit a strainer and use a plate exchanger the plant can open and clean.
- Pressurised loop. At 105 °C the hot-water loop must be held above 1.5 bar(g).
- Glass thermal shock. Keep the first tunnel zone within 30 K of the fill temperature to avoid breakage.
- 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
Hot-fill heating from cooling-tunnel heat
How a sauce and juice plant hot-filling about 34 tonnes a day can heat its product with a heat pump that recovers heat from its own bottle cooling tunnel, instead of a diesel boiler.
▶Video: Waste-heat recovery heat pumps
V10 · 2–2.5 minLifting warm water from condensers, effluent and process cooling to useful heat
Video coming soon01Problem statement
- Heat in, heat out. Product is heated to 92 °C for filling and then cooled straight back down in the tunnel. The tunnel heat goes to a cooling tower.
- Viscous product, tight temperature. Ketchup must leave the heater at a steady 88–92 °C. Too cold risks spoilage and too hot darkens colour.
- Tunnel cooling is slow in summer. Warm cooling-tower water lengthens the tunnel and limits line speed on hot days.
- Losses between fuel and process. Burning diesel 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 ketchup, sauces and fruit juice in glass and PET bottles over two shifts. Product is heated to about 92 °C in a tubular heater, filled hot, inverted, and cooled in a multi-zone spray tunnel. About 24 tonnes of ketchup and sauces and 10,000 litres of juice are filled a day.
| Heat user | Process temp. | Basis | Heat, kWh/day |
|---|---|---|---|
| Ketchup and sauce heater | 50 → 92 °C | 24 t/day (22,000 L at 1.1 kg/L), 10% losses | 1,118 |
| Juice hot-fill heater | 75 → 90 °C | 10,000 L/day after regeneration | 166 |
| Storage and pipework standing losses | – | about 5% | 64 |
| Total useful heat | 1,349 | ||
Averaged over 16 running hours, the heat pumps need about 84 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
- 4 × SE-WWUHT-27 (108 kW total) (SE-WWUHT water-source, R245fa) delivering 105 °C, covering the day's 1,349 kWh in about 12.5 running hours.
- A 3,500 L insulated storage tank decouples the heat pumps from the process peaks.
- Heat source: cooling-tunnel return water at about 50 °C. Cooling the tunnel water cuts cooling tower load and speeds bottle cooling.
- The diesel-fired steam boiler stays connected behind a normally closed valve as standby.
- The warm zones of the cooling tunnel return water at about 50 °C. This feeds the water-source heat pump, which makes hot water at about 105 °C.
- The tubular heater for sauces and the juice heater both run on this hot water, replacing steam.
- The tunnel water comes back from the heat pump cooler, so bottles cool faster in the first zones.
Selected equipment
| Model | SE-WWUHT-27 × 4 |
|---|---|
| Heating capacity | 27 kW each, 108 kW total |
| COP | 2.6 estimated for a 50 °C source (the data sheet is rated on a 60/55 °C source) |
| Rating | water or steam to 120 °C, R245fa |
| Supply temperature | 105 °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 tank top starts the heat pump below 100 °C and stops it at 105 °C. TIC-201 holds sauce at the filler at 92 °C. TIC-202 holds juice at 90 °C. If the tank falls below 96 °C, the existing steam heater is enabled 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 tonne of product | – | – |
| CO₂ per year | – | – |
06Benefits
Tunnel heat reused
The heat that cooling the bottles used to waste now heats the next product.
Faster cooling
Colder tunnel water shortens cooling time, which can help line speed in summer.
Even fill temperature
Hot water at a controlled temperature keeps viscous sauce at a steady fill temperature.
Lower energy cost
Each kWh of electricity delivers about 2.6 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.
Built-in redundancy
Several machines share the load. If one is serviced, the others and the storage carry most of the day, with the existing heater in reserve.
07Engineering pointers
Site data to collect
- Products, fill temperatures and daily volumes
- Product temperature before heating
- Tunnel zone temperatures and flow
- Existing heater type and steam use
- Line speed and running hours
- 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
- Tunnel water quality. Tunnel spray water picks up product and label debris. Fit a strainer and use a plate exchanger the plant can open and clean.
- Pressurised loop. At 105 °C the hot-water loop must be held above 1.5 bar(g).
- Glass thermal shock. Keep the first tunnel zone within 30 K of the fill temperature to avoid breakage.
- 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.