Product drying
Dry agricultural and chemical products.
- Spices and grains
- Chemical powders
- Fruit and vegetables
RESEARCH PARTNERSHIP / 09
Developed withIndian Institute of Technology Bombay#3 in engineering, NIRF 2025
Prototype provenDelivered by Rispri Labs
Waste heat recovery.
Drying and fresh water, for free.
Rispri Labs delivers compact panel heat and mass exchangers, developed with IIT Bombay, that turn low-grade waste heat into product drying and fresh water. Recover energy you are already paying for.
RESEARCH TO REALITYRispri Labs × IIT Bombay
IIT Bombay
What it means for you
Waste heat into drying and fresh water.
13.5×
more heat-transfer surface in the same space.
Free energy
Heat from compressors and DG sets dries product or makes water.
Fresh water
made from waste heat at remote and coastal sites.
Performance
More surface. Less space.
Most factories reject heat at temperatures too low for conventional exchangers to use well. A finned panel exchanger packs so much surface into its footprint that even small temperature differences do useful work.
- 13.5×
- More exchange surface per projected area
- TRL 7
- Prototype proven for waste-heat drying
- TRL 6
- Demonstrated for waste-heat desalination
- Al
- Aluminium extrusions with integrated fins
Figures are from the research team's prototype trials. Performance on your stream is confirmed in our laboratory before design.
Challenge and response
The problems this solves.
- 01The challenge
Low-grade heat from compressors and process cooling is thrown away.
How we solve itRecover it for drying or desalination.
- 02The challenge
Product drying burns fuel or electricity.
How we solve itUse waste heat as the drying energy.
- 03The challenge
Conventional exchangers need large temperature differences.
How we solve itVery high surface area works with small differences.
- 04The challenge
Remote sites pay for tanker water.
How we solve itProduce fresh water from waste heat on site.
How it works
The process, step by step.
- 1
Capture
Waste heat from compressors, DG sets or process cooling is collected.
- 2
Exchange
Finned aluminium panels transfer heat and moisture across a large surface.
- 3
Dry
Warm, dry air dries products or by-products.
- 4
Distil
In desalination mode, the panels evaporate and condense fresh water.
Use cases
Where waste heat recovery for drying and desalination delivers.
By-product and sludge drying
Reduce moisture before disposal or reuse.
- ETP sludge
- Filter cake
- Biomass
Small-scale desalination
Make fresh water from brackish or seawater.
- Coastal plants
- Remote sites
- Islands
Process heat recovery
Recover heat from compressors and DG sets.
- Air compressors
- DG exhaust
- Process cooling water
Dehumidified air
Supply dry air for sensitive processes.
- Storage
- Packaging
- Pharma
Pair with ZLD
Supply heat to the ZLD evaporator.
- Faster evaporation
- Lower energy cost
- Smaller footprint
Comparison
How it compares.
| Factor | Conventional shell-and-tube / fuel-fired drying | Rispri solution |
|---|---|---|
| Energy source | Fuel, electricity or live steam | Low-grade waste heat |
| Surface density | Standard | Up to 13.5× surface per projected area |
| Footprint | Large for low-grade heat | Compact panels |
| Construction | Fabricated tubes and shells | Aluminium extrusions with integrated fins |
| By-product | None | Fresh water in desalination mode |
Standards and regulations
Designed around the rules that apply to you.
We design each system to meet your consent conditions and the regulations for your sector, and our laboratory reports against them.
- Energy Conservation Act, 2001Framework for energy efficiency in designated consumers.
- BEE Perform, Achieve and Trade schemeEnergy-saving targets for energy-intensive industries.
- IS 10500:2012Drinking water quality for desalinated water.
- ISO 50001Energy management systems.
Industries served
Built for the sectors that need it most.
- Food and agri processing
- Chemicals
- Seawater desalination
- Circular economy and process design
- Engineering plants
- Remote and coastal sites
Why Rispri
Institute science. Industrial delivery.
Institute-developed technology
Built on patented and peer-reviewed research from our partnership with IIT Bombay.
Tested on your stream
Our accredited laboratory characterises your water or waste before design and verifies results after.
Engineering since 1999
The team that builds ETPs, STPs and ZLD plants across India takes each solution from pilot to full scale.
One accountable partner
Design, supply, installation, commissioning, operation and testing under one contract.
Questions
Frequently asked questions.
What sources of waste heat can it use?
Compressor heat, DG set and engine heat, process cooling water and other low-grade sources that are usually rejected to cooling towers.
How compact is it?
Aluminium extrusions with integrated fins give up to 13.5 times the exchange surface per projected area.
How ready is it?
It is at TRL 7 for waste-heat drying and TRL 6 for waste-heat desalination.
Can it work with your ZLD evaporator?
Yes. It can supply recovered heat to speed up rotating-disk evaporation.
How do we start?
We audit your heat sources and drying or water needs, then size a pilot unit.
Research partnerships
More solutions from our partnerships.
THE NEXT STEP
Prove it on
your own stream.
Send us a sample or tell us about your site. We will test it, recommend a configuration and set up a pilot.
Request a pilot