A systematic Design Methodology for Multicomponent Membrane Systems

Abstract Fossil fuel predominantly dominates the world energy supply. With energy demand set to increase, especially for developing countries, CO2 emissions tax and the environmental impact of high CO2 concentration in the atmosphere emphasises the need for a cost effective solution to CO2 emissions capture. Existing CO2 capture technologies are expensive, giving an opportunity for a new technology. Membrane technology is emerging has the alternative solution in the CO2 capture market. Finding the right design and configuration for a membrane system is difficult and time consuming. A simple way has been developed which makes use of a graphical representation of stages of membrane system with cost curve for optimization. This method for systematic membrane design has been tested and seen to be a useful tool in the early design phase of a membrane system. This report develops this methodology in two main areas. First, it extends the graphical methodology from a binary feed to a ternary feed by the development of new design concepts. Secondly, it expands the application of the methodology to more industries other than CO2 post combustion capture by incorporating different process scenarios into the methodology

Review of Vapour Compression Heat Pumps for High Temperature Heating using Natural Working Fluids

The use of high temperature heat pumps (HTHPs) operating with natural fluids has been shown to be a potential environmentally friendly solution to increase energy efficiency in industrial processes. Industrial processes release a significant amount of energy as low quality waste heat to the environment. This paper reviews the research and development of efficient and cost effective HTHP technology that can utilize this waste heat. Natural fluids are of focus with consideration given to the comparable technologies using synthetic fluids. This review reveals the different challenges from fluid selection, component development to system optimization. The various innovative solutions to these challenges and promising technologies for further studies are discussed. The purpose of this paper is to serve as a start point for research by bringing together ideas, simulations and experimental results as a resource or reference tool for future development in HTHP using natural working fluids.acceptedVersio

High temperature industrial heat pumps utilising natural working fluids

There is a large demand for heat typically in the temperature range 100-200⁰C in different industries. This is today often covered by fossil fuel burning or direct use of electricity. Heat pumps has to a lesser extent been utilized due to higher investment cost and limited availability of systems for these temperatures. With increasing focus on reduction of emissions and demand for improved energy efficiency the interest in development of high temperature heat pumps is increasing. Through the projects HeatUp and HighEFF the aim has been to develop heat pumps meeting the demands from industry utilizing natural working fluids. The results show that the natural refrigerants hydrocarbons, steam and fluid mixture ammonia/water all can be applied successfully to supply the required temperatures and demands within different applications. This is supported by experimental results. Economic feasibility of implementation in the industry under different conditions are evaluated and discussed depending on country. Keywords: Heat Pumps, Natural Refrigerants, Industrial, High Temperature, Energy Efficiency.acceptedVersio

The development of a hydrocarbon high temperature heat pump for waste heat recovery

Waste heat is an abundant resource that if recovered with a heat pump would increase energy efficiency in industrial processes. This will provide improvements in heat utilization and reduce the environmental impact of greenhouse gas emissions from the combustion of fossil fuel. A hydrocarbon high temperature heat pump has been developed to demonstrate the potential to deliver heat at a temperature of 115 °C. The heat pump provides heat for applications such as drying, pasteurization and other processes. Using hydrocarbons, the heat pump aims for a clean energy system. This paper reports on a 20 kW capacity cascade heat pump with propane in the low temperature cycle and butane in the high temperature cycle. Based on a theoretical model, an experimental setup is built with standard components that are commercially available. A prototype compressor is investigated for its performance at high temperature conditions. The heat pump can recover waste heat at 30 °C and deliver heat up to 115 °C. With an average heating coefficient of performance (COP) of 3.1 for a temperature lift of 58–72 K, the heat pump is a more cost efficient and environmentally friendly system compared to existing solutions of a steam boiler.acceptedVersio

Theoretical analysis for charge reduction in a 200 kW hydrocarbon hight temperature heat pump

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Performance of high temperature heat pump for simultaneous and efficient production of ice water and process heat

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Experimental Investigation of a Hydrocarbon Piston Compressor for High Temperature Heat Pumps

The global trend towards carbon neutral industries require sustainable and climate friendly heat supply. Heat pumps can meet this requirement, but the technical capability today often limit the heat supply temperature to below 90°C. The major challenge in the development of a heat pump that can deliver heat at high temperatures (115 oC) to the heat sink is the operability and performance of the compressor. The compressor electric motor cooling, lubrication stability and material durability are important physical properties to evaluate for a compressor working at high temperatures. In this study, compressors operating with natural fluids such as hydrocarbons are focused. Hydrocarbons, like butane (with high critical temperature, 152 oC), have become a viable alternative to synthetic working fluids for high temperature heat pumps. Some of the synthetic fluids will be phased down by the Kigali amendment to the Montreal protocol. Butane can operate with similar compressor technology that is familiar to propane as well as synthetic working fluids, due to the close thermodynamic properties. This study experimentally investigates the performance of a prototype butane compressor adapted for high temperature heat pumps. The compressor has been fitted with modifications specifically for high performance and high temperature heat delivery. The compressor is installed in a 20 kW cascade heat pump with propane in the low temperature cycle and butane in the high temperature cycle. The prototype compressor development can be applied in a heat pump for drying, pasteurization, sterilization, low-pressure steam production, pressurized hot water production and others that are conventionally supplied with heat by the combustion of fossil fuel in boilers or direct electric heating. It may also recover waste heat from industrial processes, thereby increasing energy efficiency. Experimental results show that the prototype compressor has an average total compressor efficiency of 74 % while delivering heat at 115 oC

High temperature industrial heat pumps utilising natural working fluids

There is a large demand for heat typically in the temperature range 100-200⁰C in different industries. This is today often covered by fossil fuel burning or direct use of electricity. Heat pumps has to a lesser extent been utilized due to higher investment cost and limited availability of systems for these temperatures. With increasing focus on reduction of emissions and demand for improved energy efficiency the interest in development of high temperature heat pumps is increasing. Through the projects HeatUp and HighEFF the aim has been to develop heat pumps meeting the demands from industry utilizing natural working fluids. The results show that the natural refrigerants hydrocarbons, steam and fluid mixture ammonia/water all can be applied successfully to supply the required temperatures and demands within different applications. This is supported by experimental results. Economic feasibility of implementation in the industry under different conditions are evaluated and discussed depending on country. Keywords: Heat Pumps, Natural Refrigerants, Industrial, High Temperature, Energy Efficiency

Design und experimentelle Resultate einer Hochtemperatur-Propan-Butan-Wärmepumpe

Thermische Prozesse in der Nahrungsmittelindustrie sind oftmals eine Kombination aus Erwärmung und Abkühlung eines Produktes. Prozesskühlung wird dabei meistens mittels einer Wärmepumpe erzielt, während für die Prozesswärme oftmals eine fossile Energiequelle genutzt wird. Kombinierte Wärmepumpensysteme, die sowohl Prozesskühlung als auch Prozesswärme liefern, haben gerade vor dem Hintergrund des Pariser Klimavertrags ein hohes Marktpotential. Im vorliegenden Fall wurde eine Propan‐Butan‐Wärmepumpe entwickelt, welche an der Wärmequelle Prozesskühlung in der Form von Wasser mit einer Temperatur von 4 °C liefert und an der Wärmesenke Heißwasser mit 115 °C bereitstellt. Hierfür wurden bewusst zwei natürliche Kältemittel eingesetzt um zukünftige Beschränkungen und Herausforderungen mit synthetischen Kältemitteln zu umgehen. Basierend auf den genannten Anforderungen wurde eine 20 kW‐Demonstrationsanlage ausgelegt, gebaut und unter variierenden Betriebsbedingungen getestet. Für den Propan‐Teilkreislauf wurden ausschließlich Standardkomponenten eingesetzt, während für den Butan‐Hochtemperaturkreislauf eine Modifikation des Kompressors erforderlich war. In den durchgeführten Experimenten wurde die kombinierte Leistungszahl der Wärmepumpe mit 2,5 ermittelt, in welcher die wasserseitigen Wärmeverluste bereits mitberücksichtig wurden. Dies bedeutet, dass für 1 kW elektrische Energie Prozesswärme von 1,7 kW bei 115 °C geliefert wurde und gleichzeitig Prozesskühlung von 0,7 kW bei 4 °C erzielt wurde. Der kombinierte Carnot‐Wirkungsgrad der Demonstrationsanlage lag somit bei circa 45 %. Das Energiesparpotenzial gegenüber einer herkömmlichen Prozesskühlung mit einem kombinierten Warmwasserboiler liegt bei 57 %. Die entwickelte Wärmepumpenlösung kann auch dazu genutzt werden um existierende Kälteanlagen nachzurüsten, bei denen die Wärmesenke derzeit nicht genutzt wird. Dies würde es beispielsweise ermöglichen die Überschussenergie von Gefrieranlagen zur Produktion von Heißwasser zu nutzen.Design und experimentelle Resultate einer Hochtemperatur-Propan-Butan-WärmepumpepublishedVersio

The development of a hydrocarbon high temperature heat pump for waste heat recovery

Waste heat is an abundant resource that if recovered with a heat pump would increase energy efficiency in industrial processes. This will provide improvements in heat utilization and reduce the environmental impact of greenhouse gas emissions from the combustion of fossil fuel. A hydrocarbon high temperature heat pump has been developed to demonstrate the potential to deliver heat at a temperature of 115 °C. The heat pump provides heat for applications such as drying, pasteurization and other processes. Using hydrocarbons, the heat pump aims for a clean energy system. This paper reports on a 20 kW capacity cascade heat pump with propane in the low temperature cycle and butane in the high temperature cycle. Based on a theoretical model, an experimental setup is built with standard components that are commercially available. A prototype compressor is investigated for its performance at high temperature conditions. The heat pump can recover waste heat at 30 °C and deliver heat up to 115 °C. With an average heating coefficient of performance (COP) of 3.1 for a temperature lift of 58–72 K, the heat pump is a more cost efficient and environmentally friendly system compared to existing solutions of a steam boiler