Gelatin extraction water heated by heat pumps
How a gelatin plant making 1 tonne of dry gelatin a day can heat its 90–100 °C extraction water from evaporator condenser water, and what it saves against a furnace-oil 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
- Five temperatures from one boiler. Each extraction draw needs water a few degrees hotter than the last. Steam injected into each kettle makes it hard to hold the set point, and overshoot darkens the extract and lowers bloom strength.
- Heat thrown away at the evaporator. The multiple-effect evaporator rejects its last-effect vapour to a surface condenser. That warm water goes straight to the cooling tower while the boiler burns oil to heat fresh water.
- Long, hot batches. The kettles sit at 90–100 °C for hours. Jacket and lid losses add up to a large share of the daily fuel bill.
- 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 extracts edible and technical gelatin from limed ossein and hide splits in batch kettles, making about 1 tonne of dry gelatin a day. Extraction runs round the clock in five successive draws from 55 °C up to 100 °C. A small side line cooks hide glue for the carpentry trade.
| Heat user | Process temp. | Basis | Heat, kWh/day |
|---|---|---|---|
| Extraction water, final draws | 90–100 °C | 3 kettles × 4,000 L, 35 → 98 °C | 878 |
| Extraction water, early draws | 55–75 °C | 10,000 L/day, 35 → 70 °C | 406 |
| Holding kettles at temperature | 90–100 °C | 6 kettles × 4 kW jacket and lid loss × 12 h | 288 |
| Hide glue cooker | 85 °C | 3,000 L glue liquor, 30 → 85 °C, cp 3.8, ρ 1.05 | 183 |
| Storage and pipework standing losses | – | about 5% | 88 |
| Total useful heat | 1,843 | ||
Averaged over 20 running hours, the heat pumps need about 92 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 108 °C, covering the day's 1,843 kWh in about 17.1 running hours.
- A 3,500 L insulated storage tank decouples the heat pumps from the process peaks.
- Heat source: evaporator surface-condenser water at about 55 °C. Cooling the condenser water lowers the evaporator's last-effect pressure and takes load off the cooling tower.
- The furnace-oil fired steam boiler stays connected behind a normally closed valve as standby.
- The heat pumps take heat from the evaporator surface-condenser water at about 55 °C and deliver pressurised hot water at 108 °C to the storage tank.
- Fresh extraction water is heated in a plate exchanger to the exact draw temperature, so the kettles no longer need live steam.
- Kettle jackets and the glue cooker are fed from the same hot-water loop through their own control valves.
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 | 108 °C |
| Storage | 3,500 L insulated tank |
Ratings from the Sunniva TDS 2026 data sheets.
Control philosophy
TT-101 at the tank top calls the heat pumps on below 102 °C and off at 108 °C. TT-102 at the bottom starts a unit early before the final 100 °C draw. TIC-201, TIC-202 and TIC-203 trim each kettle and the glue cooker to its own set point. If the tank top falls below 98 °C the existing boiler is brought in 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 dry gelatin | – | – |
| CO₂ per year | – | – |
06Benefits
Better bloom and colour
Hot water at a fixed temperature avoids the local overheating of steam injection, which protects bloom strength and keeps the extract lighter.
Evaporator heat put to work
Heat that used to go to the cooling tower now heats the next batch of extraction water.
Steady draw temperatures
Each draw starts at the planned temperature, so extraction times are repeatable from batch to batch.
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
- Number of extraction draws, volumes and temperatures
- Evaporator condenser water flow and temperatures
- Kettle sizes and insulation condition
- Glue line volumes and schedule
- Existing boiler steam use per tonne of gelatin
- 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
- Pressurised loop. Water at 108 °C must be kept under about 2.5 bar to stay liquid. Fit a pressurisation set, relief valve and expansion vessel sized for this temperature.
- Source water quality. Surface-condenser water can carry protein and fat carry-over. Use an intermediate plate exchanger or a strainer and allow for cleaning on the source side.
- Food contact. Heat pump water never mixes with extraction water. Food-grade water is heated through a separate exchanger.
- 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
Gelatin extraction water heated by heat pumps
How a gelatin plant making 1 tonne of dry gelatin a day can heat its 90–100 °C extraction water from evaporator condenser water, and what it saves against a furnace-oil 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
- Five temperatures from one boiler. Each extraction draw needs water a few degrees hotter than the last. Steam injected into each kettle makes it hard to hold the set point, and overshoot darkens the extract and lowers bloom strength.
- Heat thrown away at the evaporator. The multiple-effect evaporator rejects its last-effect vapour to a surface condenser. That warm water goes straight to the cooling tower while the boiler burns oil to heat fresh water.
- Long, hot batches. The kettles sit at 90–100 °C for hours. Jacket and lid losses add up to a large share of the daily fuel bill.
- 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 extracts edible and technical gelatin from limed ossein and hide splits in batch kettles, making about 1 tonne of dry gelatin a day. Extraction runs round the clock in five successive draws from 55 °C up to 100 °C. A small side line cooks hide glue for the carpentry trade.
| Heat user | Process temp. | Basis | Heat, kWh/day |
|---|---|---|---|
| Extraction water, final draws | 90–100 °C | 3 kettles × 4,000 L, 35 → 98 °C | 878 |
| Extraction water, early draws | 55–75 °C | 10,000 L/day, 35 → 70 °C | 406 |
| Holding kettles at temperature | 90–100 °C | 6 kettles × 4 kW jacket and lid loss × 12 h | 288 |
| Hide glue cooker | 85 °C | 3,000 L glue liquor, 30 → 85 °C, cp 3.8, ρ 1.05 | 183 |
| Storage and pipework standing losses | – | about 5% | 88 |
| Total useful heat | 1,843 | ||
Averaged over 20 running hours, the heat pumps need about 92 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 108 °C, covering the day's 1,843 kWh in about 17.1 running hours.
- A 3,500 L insulated storage tank decouples the heat pumps from the process peaks.
- Heat source: evaporator surface-condenser water at about 55 °C. Cooling the condenser water lowers the evaporator's last-effect pressure and takes load off the cooling tower.
- The furnace-oil fired steam boiler stays connected behind a normally closed valve as standby.
- The heat pumps take heat from the evaporator surface-condenser water at about 55 °C and deliver pressurised hot water at 108 °C to the storage tank.
- Fresh extraction water is heated in a plate exchanger to the exact draw temperature, so the kettles no longer need live steam.
- Kettle jackets and the glue cooker are fed from the same hot-water loop through their own control valves.
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 | 108 °C |
| Storage | 3,500 L insulated tank |
Ratings from the Sunniva TDS 2026 data sheets.
Control philosophy
TT-101 at the tank top calls the heat pumps on below 102 °C and off at 108 °C. TT-102 at the bottom starts a unit early before the final 100 °C draw. TIC-201, TIC-202 and TIC-203 trim each kettle and the glue cooker to its own set point. If the tank top falls below 98 °C the existing boiler is brought in 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 dry gelatin | – | – |
| CO₂ per year | – | – |
06Benefits
Better bloom and colour
Hot water at a fixed temperature avoids the local overheating of steam injection, which protects bloom strength and keeps the extract lighter.
Evaporator heat put to work
Heat that used to go to the cooling tower now heats the next batch of extraction water.
Steady draw temperatures
Each draw starts at the planned temperature, so extraction times are repeatable from batch to batch.
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
- Number of extraction draws, volumes and temperatures
- Evaporator condenser water flow and temperatures
- Kettle sizes and insulation condition
- Glue line volumes and schedule
- Existing boiler steam use per tonne of gelatin
- 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
- Pressurised loop. Water at 108 °C must be kept under about 2.5 bar to stay liquid. Fit a pressurisation set, relief valve and expansion vessel sized for this temperature.
- Source water quality. Surface-condenser water can carry protein and fat carry-over. Use an intermediate plate exchanger or a strainer and allow for cleaning on the source side.
- Food contact. Heat pump water never mixes with extraction water. Food-grade water is heated through a separate exchanger.
- 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.