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The use of industrial high-temperature heat pumps (HTHP) is particularly interesting for heat recovery applications and various industrial processes such as steam generation, drying, sterilization, paper production, or food preparation. The application of new synthetic hydrofluoroolefin (HFO) and hydrochlorofluoroolefin (HCFO) refrigerants with low environmental impact is becoming increasingly important in future HTHP. At our university in Switzerland, a laboratory-scale HTHP has been developed as part of the SCCER-EIP project (Swiss Competence Center for Energy Research – Efficiency of Industrial Processes). The developed heat pump is single-stage, operates with a variable speed piston compressor, and contains a continuously adjustable internal heat exchanger (IHX) for superheating control. A viscous POE oil (173 mm2/s at 40 °C) is used to achieve sufficient lubrication at high temperatures with the refrigerants. This paper presents the experimental performance of the HCFO and HFO refrigerants R1224yd(Z), R1233zd(E), and R1336mzz(Z) as drop-in replacements for the fluorinated hydrocarbon (HFC) R245fa in the same laboratory HTHP with 10 kW heating capacity. Starting from a reference point at W60/W110 (50 K temperature lift), a parameter study was performed to investigate the operating maps (i.e. heating capacity and COP) of the heat pump in the range from 30 to 80 °C heat source and 70 to 150 °C supply temperature. Besides, an overview of the thermophysical, environmental, and safety aspects of the refrigerants is given. At W60/W110 COPs of 3.2, 3.1, 3.0, and 3.1 for R1224yd(Z), R1233zd(E), R1336mzz(Z) and R245fa were measured. Up to about 110 °C, R1224yd(Z), R1233zd(E), and R245fa presented a slightly higher COP than R1336mzz(Z) due to higher heating capacities and lower relative heat losses at the same temperature conditions. Due to higher critical temperatures, R1336mzz(Z) was more efficient at 150 °C heat supply temperature. Otherwise, the differences in COP were within the measurement uncertainty of maximum ± 0.22 COP. The integration of the IHX in the heat pump cycle significantly increased the COP and the heating capacity over the entire operating map compared to a basic cycle. A further COP increase was achieved by a higher temperature glide on the heat supply side from 5 to 30 K (increased subcooling), which is promising in processes with low return temperatures. The drop-in tests also showed that the heating capacity of R1224yd(Z) was on average 9% higher than that of R1233zd(E), which in practice requires slightly smaller compressors to achieve a comparable heating capacity. Overall, the very low GWP, the non-flammability, and the negligible environmental impact (i.e. low trifluoroacetic acid (TFA) formation during atmospheric degradation) of the investigated HCFO and HFO refrigerants indicate a high potential for future use in HTHP applications and retrofit systems.

Industrial processes are currently responsible for 20 % of total greenhouse gas emissions in Europe. In order to stay within the 1.5°C scenario of the Paris Climate Agreement, measures to reduce these greenhouse gas emissions from industry are urgently needed. This paper highlights the role heat pump technologies can fulfil in realizing significant reductions in CO2 emissions arising from industrial process heating. Industrial heat pumps are a highly energy efficient, crosscutting technology to provide process heat. Driven by electric power, heat pumps are a key electri cation technology which are able to replace a large share of fossil fuelled industrial process heating. The research institutes involved in RD&D of heat pump solutions propose a European industrial heat pump program, designed to accelerate the implementation and further development of this low carbon technology. Unlocking the benefits of heat pump technology requires a set of coherent measures. This includes creating a regulatory framework that facilitates the acceptance of industrial heat pumps, setting up a European information and knowledge base on heat pump technologies and process integration as well as the establishment of an RD&D program that supports the strengthening and growth of industrial heat pump applications.

Spray drying plays a crucial role in the processing of pharmaceutical products such as pills, capsules, and tablets as it is used to convert drug containing liquids into dried powdered forms. Nano spray drying is in particular used to improve drug formulation by encapsulating active ingredients in polymeric wall materials for protection and delivering the drugs to the right place and time in the body. The nano spray dryer developed in the recent years extends the spectrum of produced powder particles to the submicron- and nanoscale with very narrow size distributions and sample quantities in the milligram scale at high product yields. This enables the economical use of expensive active pharmaceutical ingredients and pure drugs. The present paper explains the concept of nano spray drying and discusses the influence of the main process parameters on the final powder properties like particle size, morphology, encapsulation efficiency, and drug loading. Application results of nano spray drying for the formulation and encapsulation of different drugs are reviewed. Keywords: nano spray drying; pharmaceuticals; drug encapsulation; particle size; powder

Demand for heating and cooling continues to grow as populations and living standards continue to increase around the globe. At the same time, persistent uncertainty in energy prices and increasing awareness of the environmental impacts associated with the use of fossil fuels - including climate change and poor air quality - are motivating an interest in reducing energy use, in general, and fossil energy, in particular. Heat pumps with scroll or reciprocating compressors have been gaining ground for residential, commercial and industrial heating and cooling applications on a scale up to several tenths of kWmech (over 100 kWtherm). They usually reduce energy use relative to conventional approaches (e.g. fossil-fuel heating in conjunction with electrically-driven cooling) but require higher first costs. Micro-centrifugal compressors with impeller diameters as small as 10-20 mm operating at rotational speeds exceeding 100,000 rpm are now feasible. They are assembled with precisely machined components and they are driven directly (i.e. without gears) by efficient high-speed motors. They have impellers suspended without contact with solid surfaces through bearings lubricated by refrigerant vapor. Thus, they realize high efficiencies and eliminate well-known disadvantages resulting from the use and management of conventional lubricants in positive-displacement systems such as having to: i) ensure adequate lubricant circulation (especially for two stage systems), so as to prevent lubricant depletion at the compressor and associated increased wear and lubricant accumulation in heat exchangers (especially cold evaporators) and associated reduced rates of heat transfer (especially from enhanced surfaces); and ii) limit the maximum operating temperature of high-temperature heat pumps, so as to maintain long-term lubricant chemical stability. HFO-1336mzz(Z) (CF3CH=CHCF3) is a hydro-fluorolefin with a normal boiling point of 33.4 oC and an A1 safety classification (non-flammable, lower toxicity) according to ASHRAE standard 34. It has an ultra-low global warming potential over a 100 years of 2, which virtually eliminates business risk from climate protection regulations emerging around the world and allows R&D investments for technology development. It has been commercialized for use as a component in R-514A, a replacement for HCFC-123 in centrifugal chillers, as a working fluid for high temperature heat pumps and Rankine power cycles and as a foam expansion agent. This paper proposes novel heat pump systems based on micro-centrifugal compressors for selected heating and cooling applications, discusses refrigerant selection, evaluates the performance of systems with HFO-1336mzz(Z) as the refrigerant and identifies promising applications with potentially attractive economics for further development.