Significant energy saving can be achieved by utilizing MVR industrial heat pumps in thermal separation processes. MVR evaporators can reduce energy consumption by 90-99% compared to conventional systems by mechanically compressing vapor for reuse. They require practically no cooling water and are a reliable, proven technology. MVR is particularly efficient for applications like biogas reject water treatment where it can concentrate waste streams while using only 15-20 kWh of energy per ton of water evaporated.

1. Significant energy saving by
utilizing MVR industrial heat
pump in thermal separation
processes
By: Kjetil Evenmo, Senior Engineer
POLEKO 2012

2. AGENDA
 Energy systems in thermal separation
processes
 MVR – the most efficient energy system
for a number of applications
 MVR evaporator plants within Biogas
reject / waste water applications
 Other MVR thermal separation processes

3. One stage evaporator
Condenser
Evaporator
100%
100%
100%
100% Energy in = 100% evaporated = 100% cooling effect

4. 3-stage cascade evaporator
33%
33%
33%
33%
33%
33% Energy in = 100% evaporated = 33% cooling effect

5. 33%
TVR evaporator
(Thermal Vapor Recompression)
67%
33%
33%
33% Energy in = 100% evaporated = 33% cooling effect

6. 1 - 5% (electrical)
MVR evaporator
(Mechanical Vapor Recompression)
100%
Practically no
cooling water!
1 - 5% Energy in = 100% evaporated

7. MVR – the most efficient energy system: Mechanical Vapor
(MVR =
Recompression).
 90-99% reduced energy consumption
 practically no cooling water
 reliable energy system
 well proven technology
 good profitability 105oC
800
700
Energy , kWh/t
600
500
400
300 100oC
200
100
0
One stage direct steam
Typical TVR or cascade
MVR EPCON falling film MVR
evaporator (FFE-MVR)

8. Applications for EPCON MVR evaporators
 Food industry
 Biomarine industry
 Chemical industry
 Mineral & metallurgic industry
 Waste water treatment
 Biogas reject water treatment

9. Example: Biogas reject water system with EPCON MVR evaporator:
Concentrate
Feed pre-treatment
& pre-heating
Condensate
Condensate polishing if required

10. Biogas reject water plant
 FFE-MVR incl. pre-treatment
 Capacity feed: 4 to 100 tons/hour
 Energy cons. 15-20 kWh/ton evap.
 Pre-fabr. skids for outdoor installation

11. Biogas reject water plant
 EPCOVAP-MVR incl. pre-treatment
 Capacity feed: 0.5 to 4 tons/hour
 Energy cons. 30-50 kWh/ton evap.
 Pre-fabr. skids for outdoor installation

12. Other EPCON MVR thermal separation processes
MVR superheated steam dryer MVR bio-ethanol dehydration
 Several applications  Retentate: fuel quality (99.7%)
 ~80% energy saving  Feed: 85-95% ethanol
 No explosion risk  Water fraction: ~pure water
 No polluted air discharge  ~80% energy saving
 Patent application, 2011  Patented process
1200
1000
800
600
400
200
0
Typical Conventional Air Dryer System
Super Heated Steam dryer
Super Heated Steam MVR dryer

13. Other MVR heat pump applications
 MVR for distillation processes (example: bio-ethanol)
 Rebuilding of existing high energy demanding evaporators to
MVR energy system
 Energy saving: 80 – 95%
Existing cascade
evaporator
After rebuild
with MVR
Original 5-stage cascade
evaporator converted to MVR

14. THANKS FOR YOUR ATTENTION!