Cane juice preheated with evaporator heat
How a 40 tonne-cane-per-day jaggery plant can preheat its cane juice with a heat pump fed from its evaporator condenser, and free bagasse for sale.
▶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
- Juice heating on the furnace. Raw juice is heated from about 30 °C to 90 °C for clarification, using fuel that the final pans also need.
- Vapour heat lost. Vapour from concentration is condensed with cooling water and its heat is rejected.
- Bagasse has a value. Bagasse burnt for low-temperature heating could be sold to paper mills or cogeneration plants.
- Losses between fuel and process. Burning briquettes 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 crushes about 40 tonnes of cane a day in season to make jaggery blocks and powder. About 20,000 litres of juice is heated, clarified and concentrated in a closed evaporator before final boiling in pans. The season runs about five months.
| Heat user | Process temp. | Basis | Heat, kWh/day |
|---|---|---|---|
| Raw juice preheating | 30 → 90 °C | 20,000 L/day juice | 1,355 |
| Clarifier hold | 90–95 °C | 2 tanks × 4 kW losses × 16 h | 128 |
| Storage and pipework standing losses | – | about 5% | 74 |
| Total useful heat | 1,558 | ||
Averaged over 18 running hours, the heat pumps need about 87 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 100 °C, covering the day's 1,558 kWh in about 14.4 running hours.
- A 3,500 L insulated storage tank decouples the heat pumps from the process peaks.
- Heat source: evaporator vapour-condenser water at about 55 °C. Cooling the vapour-condenser water improves evaporator vacuum and lowers cooling water demand.
- The bagasse and briquette fired furnace stays connected behind a normally closed valve as standby.
- Water from the evaporator vapour condenser, at about 55 °C, is the heat pump source.
- Raw juice is heated to 90 °C in a tubular or wide-gap plate heater on heat pump hot water.
- The clarifier tanks are held at temperature from the same loop.
- Evaporation itself suits mechanical vapour recompression (MVR), which can be studied as a separate project.
Selected equipment
| Model | SE-WWUHT-27 × 4 |
|---|---|
| Heating capacity | 27 kW each, 108 kW total |
| COP | 2.93 at the data sheet's rated condition (60/55 °C source water) |
| Power input | about 36.8 kW total at rated conditions |
| Rating | water or steam to 120 °C, R245fa |
| Supply temperature | 100 °C |
| Storage | 3,500 L insulated tank |
Ratings from the Sunniva TDS 2026 data sheets.
Control philosophy
TT-101 at the tank top starts the heat pump below 95 °C and stops it at 100 °C. TIC-201 holds juice at 90 °C at the clarifier inlet. TIC-202 holds the clarifier tanks at 90–95 °C. If the tank falls below 92 °C, the existing furnace heating is used 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 cane | – | – |
| CO₂ per year | – | – |
06Benefits
Bagasse freed for sale
Less bagasse burnt for juice heating leaves more to sell.
Better clarification
Juice reaches clarification temperature steadily, which helps settling and colour.
Evaporator heat reused
Condenser heat that went to the cooling pond now heats raw juice.
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.
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
- Cane crushed per day and juice volume
- Juice temperature in and clarification temperature
- Evaporator type and condenser water flow and temperature
- Bagasse output and current sale price
- Season length
- 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
- Juice fouling. Raw cane juice scales and fouls heaters fast. Use tubular or wide-gap exchangers and clean them on a schedule.
- Seasonal use. With about 150 days a year, payback depends on bagasse value. Consider a second use off season.
- Source availability. The source exists only while the evaporator runs. Start juice heating on the furnace until vapour is available.
- Electrical. About 37 kW of heat pump input at rated conditions, plus pumps and fans. Check spare sanctioned load before ordering.
- 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.
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
Cane juice preheated with evaporator heat
How a 40 tonne-cane-per-day jaggery plant can preheat its cane juice with a heat pump fed from its evaporator condenser, and free bagasse for sale.
▶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
- Juice heating on the furnace. Raw juice is heated from about 30 °C to 90 °C for clarification, using fuel that the final pans also need.
- Vapour heat lost. Vapour from concentration is condensed with cooling water and its heat is rejected.
- Bagasse has a value. Bagasse burnt for low-temperature heating could be sold to paper mills or cogeneration plants.
- Losses between fuel and process. Burning briquettes 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 crushes about 40 tonnes of cane a day in season to make jaggery blocks and powder. About 20,000 litres of juice is heated, clarified and concentrated in a closed evaporator before final boiling in pans. The season runs about five months.
| Heat user | Process temp. | Basis | Heat, kWh/day |
|---|---|---|---|
| Raw juice preheating | 30 → 90 °C | 20,000 L/day juice | 1,355 |
| Clarifier hold | 90–95 °C | 2 tanks × 4 kW losses × 16 h | 128 |
| Storage and pipework standing losses | – | about 5% | 74 |
| Total useful heat | 1,558 | ||
Averaged over 18 running hours, the heat pumps need about 87 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 100 °C, covering the day's 1,558 kWh in about 14.4 running hours.
- A 3,500 L insulated storage tank decouples the heat pumps from the process peaks.
- Heat source: evaporator vapour-condenser water at about 55 °C. Cooling the vapour-condenser water improves evaporator vacuum and lowers cooling water demand.
- The bagasse and briquette fired furnace stays connected behind a normally closed valve as standby.
- Water from the evaporator vapour condenser, at about 55 °C, is the heat pump source.
- Raw juice is heated to 90 °C in a tubular or wide-gap plate heater on heat pump hot water.
- The clarifier tanks are held at temperature from the same loop.
- Evaporation itself suits mechanical vapour recompression (MVR), which can be studied as a separate project.
Selected equipment
| Model | SE-WWUHT-27 × 4 |
|---|---|
| Heating capacity | 27 kW each, 108 kW total |
| COP | 2.93 at the data sheet's rated condition (60/55 °C source water) |
| Power input | about 36.8 kW total at rated conditions |
| Rating | water or steam to 120 °C, R245fa |
| Supply temperature | 100 °C |
| Storage | 3,500 L insulated tank |
Ratings from the Sunniva TDS 2026 data sheets.
Control philosophy
TT-101 at the tank top starts the heat pump below 95 °C and stops it at 100 °C. TIC-201 holds juice at 90 °C at the clarifier inlet. TIC-202 holds the clarifier tanks at 90–95 °C. If the tank falls below 92 °C, the existing furnace heating is used 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 cane | – | – |
| CO₂ per year | – | – |
06Benefits
Bagasse freed for sale
Less bagasse burnt for juice heating leaves more to sell.
Better clarification
Juice reaches clarification temperature steadily, which helps settling and colour.
Evaporator heat reused
Condenser heat that went to the cooling pond now heats raw juice.
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.
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
- Cane crushed per day and juice volume
- Juice temperature in and clarification temperature
- Evaporator type and condenser water flow and temperature
- Bagasse output and current sale price
- Season length
- 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
- Juice fouling. Raw cane juice scales and fouls heaters fast. Use tubular or wide-gap exchangers and clean them on a schedule.
- Seasonal use. With about 150 days a year, payback depends on bagasse value. Consider a second use off season.
- Source availability. The source exists only while the evaporator runs. Start juice heating on the furnace until vapour is available.
- Electrical. About 37 kW of heat pump input at rated conditions, plus pumps and fans. Check spare sanctioned load before ordering.
- 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.
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.