Shrimp thawing and cooking with ice-plant heat
How a seafood export plant cooking 10 tonnes and thawing 8 tonnes of shrimp a day can heat its water with a heat pump fed from its refrigeration condensers, 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
- Cooking yield depends on temperature. Overcooking shrimp by even a minute loses weight and value. Steam-fed cookers swing in temperature.
- Thawing wastes water. Thawing blocks under running water uses large volumes. Recirculating it means the water must be reheated.
- Heat rejected nearby. The ice plant and freezers reject heat to cooling towers next to the cooking line.
- 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 processes shrimp for export as cooked and peeled IQF product. It cooks about 10 tonnes a day in a continuous cooker and thaws about 8 tonnes of frozen block shrimp for reprocessing. An ice plant, plate freezers and an IQF tunnel run round the clock.
| Heat user | Process temp. | Basis | Heat, kWh/day |
|---|---|---|---|
| Shrimp cooking | 5 → 75 °C core, water 90–95 °C | 10,000 kg/day, cp 3.6 kJ/kg·K, 10% cooker losses | 770 |
| Thawing of frozen blocks | Water 20 °C | 8,000 kg × 300 kJ/kg (ice melt and warm-up to 4 °C) ÷ 3,600, recirculated thaw water reheated | 667 |
| Storage and pipework standing losses | – | about 5% | 72 |
| Total useful heat | 1,509 | ||
Averaged over 20 running hours, the heat pumps need about 75 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 80 kW, two-stage water-source machine built to duty, lifting 32 °C to 95 °C.
- A 2,500 L insulated storage tank decouples the heat pumps from the process peaks.
- Heat source: ice plant and IQF condenser water at about 32 °C. Cooling the condenser water lowers head pressure on the ice plant and freezers.
- The diesel-fired steam boiler stays connected behind a normally closed valve as standby.
- Condenser water from the ice plant and freezers at about 32 °C is the heat pump source.
- Cooker water recirculates through a plate exchanger heated from the hot-water tank, replacing steam injection.
- Thawing tanks recirculate their water through a coil fed from the same loop, holding 20 °C and saving fresh water.
Selected equipment
| Machine | Customized water-source cascade |
|---|---|
| Capacity | about 80 kW, built to duty |
| Concept | two-stage water-source machine built to duty, lifting 32 °C to 95 °C |
| COP used | 2.3 (estimate) |
| Supply temperature | 95 °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 at the tank top starts the heat pump below 90 °C and stops it at 95 °C. TIC-201 holds cooker water at 92 °C. TIC-202 holds thaw water at 20 °C and never above 22 °C. If the tank falls below 88 °C, the existing steam supply to the cooker 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 shrimp | – | – |
| CO₂ per year | – | – |
06Benefits
Better cooking yield
Steady cooker temperature helps hold weight loss to the target.
Water saving in thawing
Recirculated thaw water reheated by the heat pump replaces once-through running water.
Freezing plant helped
Taking heat from the condenser water lowers head pressure on the ice plant and freezers.
Lower energy cost
Each kWh of electricity delivers about 2.3 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
- Daily cooked and thawed quantities
- Cooker type, water temperature and cook time
- Thawing method and water use
- Refrigeration capacity and condenser water temperature
- Plant water chloride level
- 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
- Thaw water hygiene. Keep thaw water chlorinated and filtered when it is recirculated, and change it each shift.
- Low-temperature duty. Thawing needs heat at only 20 °C. A tap off the source loop can do part of this directly.
- Salt and corrosion. Seafood plants have chlorides in water and air. Use SS316 or titanium plates and coated outdoor coils.
- 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
Shrimp thawing and cooking with ice-plant heat
How a seafood export plant cooking 10 tonnes and thawing 8 tonnes of shrimp a day can heat its water with a heat pump fed from its refrigeration condensers, 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
- Cooking yield depends on temperature. Overcooking shrimp by even a minute loses weight and value. Steam-fed cookers swing in temperature.
- Thawing wastes water. Thawing blocks under running water uses large volumes. Recirculating it means the water must be reheated.
- Heat rejected nearby. The ice plant and freezers reject heat to cooling towers next to the cooking line.
- 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 processes shrimp for export as cooked and peeled IQF product. It cooks about 10 tonnes a day in a continuous cooker and thaws about 8 tonnes of frozen block shrimp for reprocessing. An ice plant, plate freezers and an IQF tunnel run round the clock.
| Heat user | Process temp. | Basis | Heat, kWh/day |
|---|---|---|---|
| Shrimp cooking | 5 → 75 °C core, water 90–95 °C | 10,000 kg/day, cp 3.6 kJ/kg·K, 10% cooker losses | 770 |
| Thawing of frozen blocks | Water 20 °C | 8,000 kg × 300 kJ/kg (ice melt and warm-up to 4 °C) ÷ 3,600, recirculated thaw water reheated | 667 |
| Storage and pipework standing losses | – | about 5% | 72 |
| Total useful heat | 1,509 | ||
Averaged over 20 running hours, the heat pumps need about 75 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 80 kW, two-stage water-source machine built to duty, lifting 32 °C to 95 °C.
- A 2,500 L insulated storage tank decouples the heat pumps from the process peaks.
- Heat source: ice plant and IQF condenser water at about 32 °C. Cooling the condenser water lowers head pressure on the ice plant and freezers.
- The diesel-fired steam boiler stays connected behind a normally closed valve as standby.
- Condenser water from the ice plant and freezers at about 32 °C is the heat pump source.
- Cooker water recirculates through a plate exchanger heated from the hot-water tank, replacing steam injection.
- Thawing tanks recirculate their water through a coil fed from the same loop, holding 20 °C and saving fresh water.
Selected equipment
| Machine | Customized water-source cascade |
|---|---|
| Capacity | about 80 kW, built to duty |
| Concept | two-stage water-source machine built to duty, lifting 32 °C to 95 °C |
| COP used | 2.3 (estimate) |
| Supply temperature | 95 °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 at the tank top starts the heat pump below 90 °C and stops it at 95 °C. TIC-201 holds cooker water at 92 °C. TIC-202 holds thaw water at 20 °C and never above 22 °C. If the tank falls below 88 °C, the existing steam supply to the cooker 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 shrimp | – | – |
| CO₂ per year | – | – |
06Benefits
Better cooking yield
Steady cooker temperature helps hold weight loss to the target.
Water saving in thawing
Recirculated thaw water reheated by the heat pump replaces once-through running water.
Freezing plant helped
Taking heat from the condenser water lowers head pressure on the ice plant and freezers.
Lower energy cost
Each kWh of electricity delivers about 2.3 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
- Daily cooked and thawed quantities
- Cooker type, water temperature and cook time
- Thawing method and water use
- Refrigeration capacity and condenser water temperature
- Plant water chloride level
- 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
- Thaw water hygiene. Keep thaw water chlorinated and filtered when it is recirculated, and change it each shift.
- Low-temperature duty. Thawing needs heat at only 20 °C. A tap off the source loop can do part of this directly.
- Salt and corrosion. Seafood plants have chlorides in water and air. Use SS316 or titanium plates and coated outdoor coils.
- 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.