DeCarbCH Wiki Technologies - Heat Pumps

Steam Generating Heat Pump


Description

Steam generating heat pump is a subject of high interest by many industrial sector as steam is used in many processes such as distillation, pasteurisation, and cleaning in place. The SFOE-funded project IntSGHP has been looking into this topic. Steam is currently a major heating medium for Swiss industries. As energy prices of fossil fuel has always be low and has only a minor impact on the final industrial products, industrial sector have been using oil and gas to heat their building and gas, often producing steam at the higher temperature needed in the plant and decreasing its pressure using expansion valves before the different processes. That leads to very low exergy efficiency.
The SFOE-funded DeCarb-PUI is focused on this subject. When CO2 production was not considered a problem, this solution was the easiest in terms of engineering (having a central steam boiler and less piping) and control (having a higher than necessary heat source available). Many Swiss plants are now pledging to become carbon neutral by 2050 or before. The simplest solution would be to replace the fossil-fuel boiler with another boiler using renewable fuel such as biomass or biogas, however, as this biofuel are far more expensive as fossil-fuel or will be in the future, industry are looking to increase their heating system efficiency by using rethink, reduce, recover, and replace strategy.
As found by many research teams member of DeCarbCH, many industrial processes using steam nowadays do not need such high temperature and could used hot water as their heat source.
Main hindrance to its implementation

Unfortunately for certain cases, the replacement of heat exchanger to be able to switch from steam to water is too costly or even to uncertain to keep the quality of the product. In theses cases, the solution is either using biofuel or a steam generating heat pump.
Heat pump cycles for steam generation

Many different heat pump cycles can be used to generate steam, some are much more efficient than others (details in [1]). There is a lack of running steam generating heat pump currently leading to a reluctance from the industries which are not willing to take risk of a product not being tested fully for years.
To overcome, this hindrance, the SFOE can financially help innovative projects get off the ground with their P&D program.
Webinars

Two webinars on steam generating heat pump have been organised in 2023 and recently in March 2024. The recordings of the 2023 and 2024 Steam Generating Heat Pump Webinar is freely available online: here and here
Guideline

A Guideline to help industries starting a project on steam generating heat pump integration, from the IntSGHP project is also available here (note: draft version).
References

[1]: Bless, F.; Arpagaus, C.; Bertsch, S.: Theoretical Investigation of High-Temperature Heat Pump Cycles for Steam Generation, 13th IEA Heat Pump Conference, Jeju, Korea, 11-14 May 2020, postponed to 26 -29 April 2021.