Pharma granules dried with dry, warm air
How a formulation plant drying 1,500 kg of wet granules a day can use heat pump drying air at 50–65 °C in place of electric air heaters.
▶Video: Industrial drying and dehumidifying
V09 · 2–2.5 minSludge, green-ware, pharma granules and storage rooms
Video coming soon01Problem statement
- Humid inlet air in the monsoon. Ambient air in coastal and monsoon months carries so much moisture that drying times stretch and loss on drying results vary batch to batch.
- Electric heating is costly. Resistance heaters convert one unit of power into one unit of heat, and dryers are among the largest power users in a formulation block.
- Heat-sensitive actives. Many actives degrade above 60 to 65 °C, so drying cannot be sped up by raising temperature.
- Electric heating is expensive heat. Resistance heaters turn one kWh of electricity into one kWh of heat, at the full commercial tariff. A heat pump moves two to four kWh of heat for the same unit.
- Large connected load. Heater banks take a big share of the sanctioned load and push up maximum-demand charges.
02Use case
The reference plant makes tablets and capsules on two shifts. Wet granulation produces about 1,200 kg of granules a day for the fluid bed dryers, and tray dryers handle a further 300 kg of wet powder.
| Product | Drying | Basis | Water removed, kg/day | Conventional heat, kWh/day |
|---|---|---|---|---|
| Fluid bed drying of granules | Inlet air 55–65 °C | 1,200 kg wet granules/day, 25% → 2% moisture | 282 | 507 |
| Tray drying of powders | Air 50–55 °C | 300 kg wet powder/day, 30% → 3% moisture | 84 | 150 |
| Total | 365 | 657 | ||
Conventional hot-air dryers use about 1.8 kWh of heat per kg of water removed. That figure is the baseline the savings are measured against.
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
- 1 × SE-AA-DR-21 (21 kW) heat pump drying module, removing about 365 kg of water a day in roughly 15 running hours.
- The electric air heaters on fluid bed and tray dryers stays connected behind a normally closed valve as standby.
- The heat pump dryer dehumidifies and heats the process air before the existing HEPA filters, giving dry air at 55–65 °C all year.
- On tray dryers the air loop is closed through the heat pump, so moisture leaves as condensate.
- The existing electric heaters stay in the air path for final trim and as standby.
Selected equipment
| Model | 1 × SE-AA-DR-21 |
|---|---|
| Heating capacity | 21 kW each, 21 kW total |
| Dehumidifying | about 25 L/h total (pro rata to the published 12–120 L/h range) |
| Drying air | rated 70 °C, 75 °C maximum |
| Refrigerant | R134a |
| Ambient | −5 to 43 °C |
| Water removed per kWh | about 2.4 kg |
Ratings from the Sunniva TDS 2026 data sheets.
Control philosophy
TIC-201 holds inlet air temperature for each batch recipe and a dew-point sensor holds inlet humidity. The electric heater trims only if the inlet falls below set-point. Batch end is still decided by product temperature and loss on drying, as in the validated process.
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 granules | – | – |
| CO₂ per year | – | – |
06Benefits
Consistent batches
Inlet air at a fixed dew point removes the seasonal swing in drying time and loss on drying.
Gentle on actives
Dry air dries faster at the same temperature, so heat-sensitive products are not pushed hotter.
Lower power bill
The heat pump uses a fraction of the electricity of resistance heaters for the same heat.
Heat recovered from the moisture
The evaporator condenses water out of the air and the condenser puts that latent heat back into the drying air, so about 2.4 kg of water leaves per kWh of electricity.
Closed loop, clean product
Air recirculates inside the chamber. No dust, smoke or outside humidity reaches the product, whatever the weather.
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
- Granulation batch size and batches per day
- Present inlet air temperature, airflow and drying time
- Loss on drying limits per product
- Heater rating on each dryer
- Validation and change-control requirements
- 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
- Validation. Changing the air handling of a validated dryer is a change control. Plan qualification runs and keep inlet temperature, airflow and dew point within the validated ranges.
- Containment. Keep the heat pump coils upstream of the product filters so no powder reaches them, and keep the process air path cleanable.
- Solvent granulation. Granules wet with alcohol or other solvents need a solvent-rated dryer. Do not use a standard closed-loop unit for solvent-wet product.
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
Pharma granules dried with dry, warm air
How a formulation plant drying 1,500 kg of wet granules a day can use heat pump drying air at 50–65 °C in place of electric air heaters.
▶Video: Industrial drying and dehumidifying
V09 · 2–2.5 minSludge, green-ware, pharma granules and storage rooms
Video coming soon01Problem statement
- Humid inlet air in the monsoon. Ambient air in coastal and monsoon months carries so much moisture that drying times stretch and loss on drying results vary batch to batch.
- Electric heating is costly. Resistance heaters convert one unit of power into one unit of heat, and dryers are among the largest power users in a formulation block.
- Heat-sensitive actives. Many actives degrade above 60 to 65 °C, so drying cannot be sped up by raising temperature.
- Electric heating is expensive heat. Resistance heaters turn one kWh of electricity into one kWh of heat, at the full commercial tariff. A heat pump moves two to four kWh of heat for the same unit.
- Large connected load. Heater banks take a big share of the sanctioned load and push up maximum-demand charges.
02Use case
The reference plant makes tablets and capsules on two shifts. Wet granulation produces about 1,200 kg of granules a day for the fluid bed dryers, and tray dryers handle a further 300 kg of wet powder.
| Product | Drying | Basis | Water removed, kg/day | Conventional heat, kWh/day |
|---|---|---|---|---|
| Fluid bed drying of granules | Inlet air 55–65 °C | 1,200 kg wet granules/day, 25% → 2% moisture | 282 | 507 |
| Tray drying of powders | Air 50–55 °C | 300 kg wet powder/day, 30% → 3% moisture | 84 | 150 |
| Total | 365 | 657 | ||
Conventional hot-air dryers use about 1.8 kWh of heat per kg of water removed. That figure is the baseline the savings are measured against.
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
- 1 × SE-AA-DR-21 (21 kW) heat pump drying module, removing about 365 kg of water a day in roughly 15 running hours.
- The electric air heaters on fluid bed and tray dryers stays connected behind a normally closed valve as standby.
- The heat pump dryer dehumidifies and heats the process air before the existing HEPA filters, giving dry air at 55–65 °C all year.
- On tray dryers the air loop is closed through the heat pump, so moisture leaves as condensate.
- The existing electric heaters stay in the air path for final trim and as standby.
Selected equipment
| Model | 1 × SE-AA-DR-21 |
|---|---|
| Heating capacity | 21 kW each, 21 kW total |
| Dehumidifying | about 25 L/h total (pro rata to the published 12–120 L/h range) |
| Drying air | rated 70 °C, 75 °C maximum |
| Refrigerant | R134a |
| Ambient | −5 to 43 °C |
| Water removed per kWh | about 2.4 kg |
Ratings from the Sunniva TDS 2026 data sheets.
Control philosophy
TIC-201 holds inlet air temperature for each batch recipe and a dew-point sensor holds inlet humidity. The electric heater trims only if the inlet falls below set-point. Batch end is still decided by product temperature and loss on drying, as in the validated process.
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 granules | – | – |
| CO₂ per year | – | – |
06Benefits
Consistent batches
Inlet air at a fixed dew point removes the seasonal swing in drying time and loss on drying.
Gentle on actives
Dry air dries faster at the same temperature, so heat-sensitive products are not pushed hotter.
Lower power bill
The heat pump uses a fraction of the electricity of resistance heaters for the same heat.
Heat recovered from the moisture
The evaporator condenses water out of the air and the condenser puts that latent heat back into the drying air, so about 2.4 kg of water leaves per kWh of electricity.
Closed loop, clean product
Air recirculates inside the chamber. No dust, smoke or outside humidity reaches the product, whatever the weather.
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
- Granulation batch size and batches per day
- Present inlet air temperature, airflow and drying time
- Loss on drying limits per product
- Heater rating on each dryer
- Validation and change-control requirements
- 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
- Validation. Changing the air handling of a validated dryer is a change control. Plan qualification runs and keep inlet temperature, airflow and dew point within the validated ranges.
- Containment. Keep the heat pump coils upstream of the product filters so no powder reaches them, and keep the process air path cleanable.
- Solvent granulation. Granules wet with alcohol or other solvents need a solvent-rated dryer. Do not use a standard closed-loop unit for solvent-wet product.
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.