This work embraces two different manufacturing processes: pultrusion androtational moulding. One (pultrusion) is concerned with manufacture with athermosetting composite while the other is concerned with manufacture of anunfilled thermoplastic. The connecting theme is one of energy usage in manufacturewith these processes. While a large number of comprehensive computer models of pultrusion havebeen generated, most are focussed on the prediction of the temperature andconversion distributions within the profile; by contrast, the analysis presented here isdirected towards the prediction of the duty cycle of the mould heaters as a first stepin recognising the significance of the energy consumed in the process. The results ofthe model are compared with experimental measurements of the duty cycle of anindustrial machine. The nature of this particular investigation was predominantlyapplied and in particular directed towards industrial use. For this reason, the modelwas created in MATLAB, a software package which is relatively more accessible tothe reinforced plastics industry than FE packages. The project involved extensivemodelling and experimentation. It is shown that the line speed could be increased significantly by preheatingthe profile before it enters the die. For example, line speed for one particular profilewas increased from 0.4m/min to 0.5 m/min by using a pre-heater set at 80°C. Thiswork also showed that the specific energy consumption of the process was 0.2kWh/kg to 0.3 kWh/kg; under different line speeds and operating conditions. Thiswas achieved by measuring the duty cycle of the heaters on the die. This increase inline speed means a saving of up to 30 % of the specific energy consumption in thepultrusion. The energy theme continues through the work on rotational moulding. It isshown that the specific energy consumption in rotational moulding can be reducedby up to 70% by direct heating of the mould by using electrical resistance heatersinstead of current method of using hot air to heat the mould. The finite elementmodel showed that this alternative heating method is capable of producing asuniform a heat distribution on the surface of the mould as the current heating systemby using cyclic heating.

Mjölkindustrin tillhör en av världens största industrier, och är den snabbaste växande sektorn inom jordbruksnäring. Varje år produceras cirka 800 miljoner ton mjölk världen över, varav svenskar årligen konsumerar cirka 150 kg mejeriprodukter per person. Framställningen av mejeriprodukter innefattar ett flertal processer som kräver stora mängder energi, främst i form av ånga till upphettning av mjölk och vatten samt elektricitet till kylning. Anledningen till att mjölken genomgår diverse behandlingar är framförallt för att döda skadliga bakterier och sporer men också ur kvalitetssynpunkt. För att möta de miljömässiga utmaningar vi står inför krävs att nya hållbara lösningar utvecklas och implementeras. Enligt miljöbalken ska verksamheter använda förnybara energikällor i den utsträckning det är möjligt, återvinning av värme skall nyttiggöras och det ska hushållas med såväl energi som andra resurser. Wermlands Mejeri, beläget i Värmlands Nysäter, startade sin verksamhet i september 2015. Mejeriet framställer dagligen 18 400 liter lättmjölk, mellanmjölk, standardmjölk och grädde, med målet att till augusti 2016 dubbla produktionen med samma sortiment. Syftet med del I av denna studie är att utföra en energikartläggning för att bestämma mejeriets totala energibehov samt hur behovet är fördelat på diverse processer. Energiinventeringens syfte utöver att skapa insikt i hur energianvändningen är fördelad är att ligga som grund för jämförelser med liknande anläggningar. På så vis kan en uppfattning om förbättringspotential erhållas. Vid jämförelser mellan olika anläggningar har nyckelvärdet specifik energikonsumtion, SEC, använts.  SEC definieras som använd energi dividerat med den totala produktionsvolymen och kan appliceras på en delprocess eller en hel produktionsanläggning. Analyser av energianvändning och effektiviseringspotential har utförts genom termodynamiska beräkningar, fysiska mätningar, simuleringar och ingenjörsmässiga uppskattningar. Enligt den kartläggning som gjorts förbrukar Wermlands mejerier idag 1141 MWh per år, vilket motsvarar ett SEC-värde på 0,19 kWh/liter mjölkprodukt. Vid en fördubbling av produktionen skulle energianvändningen öka till 1570 MWh per år och SEC-värdet reduceras till 0,13 kWh/l varav värmebehovet representerar 0,09 kWh/l. Två svenska referensanläggningar som använts vid jämförelser har ett totalt SEC-värde på 0,11 respektive 0,12 kWh/liter mjölkprodukt där värmebehovets SEC-värde är 0,05 respektive 0,06 kWh/l. Syftet med del två av studien är således att belysa förbättringspotential genom reducerat värmebehov och ånganvändande. Målet är att presentera åtgärder som sänker och tillgodoser energibehovet utan förbränning av fossila bränslen. Resultatet visar att bränslebehovet kan reduceras från 105 till 782 MWh/år med olika åtgärder. Bränslekostnaden utan åtgärder antas vid dubblad produktion uppgå till drygt 750 000 SEK per år. Vid utbyte till pelletspanna och med samtliga åtgärder genomförda är bränslekostnaden 250 000 SEK/år och koldioxidutsläppen reducerades med över 1000 ton/år. Totala SEC-värdet på värmesidan reduceras då från 0,09 kWh/l till 0,06 kWh/l vilket är jämförbart med de svenska referensanläggningarna. / The dairy industry is one of the world’s largest industries, and the most rapidly expanding sector of agriculture. Every year more than 800 million tons of milk is produced globally, of which the Swedish population annually consumes more than 150 kg per capita. Refinement of milk includes several processes that require large amounts of energy, mainly in the form of steam for heating of milk and electricity for cooling. The main reasons the milk has to go through these heating and cooling process is to reduce the bacterial count, rendering the product safe to drink and of a consistent quality. To meet the environmental challenges that lie ahead, it is important that sustainable solutions for the dairy industry are developed and implemented. According to the environmental code, all industries shall use renewable energy sources to the highest possible degree, recycling of heat shall be used and housekeeping of energy and other resources is of uttermost importance. Wermlands Mejeri, a dairy plant in Värmlands Nysäter, started their operations in September 2015. Today they produce about 18 400 liters of dairy product, with a product portfolio consisting of three different types of milk (0.5, 1.8, and 3 percent fat) and cream. Their goal is to expand the operation, so that the production volume will be doubled by august 2016. The commencing chapter of this report is based on a survey with the goal of defining the total energy consumption at the plant, and also to investigate how the need of energy is divided between the different processes. This survey is purposed to be compared to the energy consumption at other similar dairy plants, in order to point out if (and where) there is any potential to increase the energy efficiency. When comparing different facilities, the key indicator Specific Energy Consumption (SEC) is used. SEC is defined as the total used energy divided by the amount of product, and can be applied on specific processes as well as an entire operation. According to the analysis, Wermlands mejerier consumes 1141 MWh yearly, which corresponds to a SEC index of 0.19kWh/liter milk product. A doubling of the milk production would lead to an increase in energy use to 1570 MWh/year, and a reduction in SEC to 0.13 kWh/l of which the heating system stands for 0.09 kWh/l. The two Swedish reference factories which were used as comparison have an SEC index of 0.11 and 0.12 kWh/l milk product, of which the heating system stands for 0.05 and 0.06 kWh/l, respectively. The aim of the second part of the study is to highlight the potential for improvement by reducing the heating demand and steam usage. The goal is to suggest practice changes that reduce and meet the need for energy without burning fossil fuels. The study shows that the fuel usage can be reduced from 1050 to 782 kWh/year by different interventions. Without these interventions, the fuel cost is expected to reach over 750,000 SEK/year when doubling the production. If all interventions, including changing to pellet boiler, are implemented, the fuel cost will be 150,000 SEK/year and the carbon dioxide emissions reduced by over 1,000 tons yearly. The total SEC index of the heating system will then be reduced from 0.09 to 0.06 kWh/l, which is comparable to the Swedish reference factories.

Yes / The successful use of Reverse Osmosis (RO) process has increased significantly in water desalination, water treatment and food processing applications. In this work, the economic feasibility of a multi-stage RO process including both retentate and permeate reprocessing for the removal of chlorophenol from wastewater is explored using simulation and optimisation studies. Firstly, a mathematical model of the process is developed based on the solution diffusion model, which was validated using experimental chlorophenol removal from the literature, is combined with several appropriate cost functions to form a full model package. Secondly, for a better understanding of the interactions between the different parameters on the economic performance of the process, a detailed process simulation is carried out. Finally, a multi-objective optimisation framework based on Non-Linear Programming (NLP) problem is developed for minimising the product unit cost, the total annualised cost, the specific energy consumption together with optimising the feed pressure and feed flow rate for an acceptable level of chlorophenol rejection and total water recovery rate. The results clearly show that the removal of chlorophenol can reach 98.8% at a cost of approximately 0.21 $/m³.

Yes / Brackish water can be considered an important source of fresh water, via desalination, especially for arid districts. Reverse Osmosis (RO) process has been successfully used to produce fresh water from brackish water sources. However, there is still the challenge of improving the performance of multistage RO desalination plants. From the selection of the RO configurations to the selection of the appropriate type of membranes and the operating conditions at the end determines the performance of RO process in terms of recovery, salt rejection, energy consumptions and ultimately the cost of production of freshwater. Using model-based simulation, this work attempts to investigate the most suitable types of membranes for an industrial scale RO plant from a set of different membrane brands that would attain the highest-performance at lowest specific energy consumption (SEC). As a case study, we considered a multistage multi-pass medium-scale RO plant (1200 m3/day) of Arab Potash Company (APC, Jordan) which produces high quality water for the boilers after pre-treatment stage. The simulation results confirmed that employment of the Filmtec BW30LE-440 would increase water recovery by about 22% besides reducing the product salinity and SEC by about 15% and 10%, respectively compared to the existing membrane.

Yes / Polymer extrusion is an important but an energy intensive method of processing polymeric materials. The rapid increase in demand of polymeric products has forced manufactures to rethink their processing efficiencies to manufacture good quality products with low-unit-cost. Here, analyzing the operational conditions has become a key strategy to achieve both energy and thermal efficiencies simultaneously. This study aims to explore the effects of polymers' rheology on the energy consumption and melt thermal quality (ie, a thermally homogeneous melt flow in both radial and axil directions) of extruders. Six commodity grades of polymers (LDPE, LLDPE, PP, PET, PS, and PMMA) were processed at different conditions in two types of continuous screw extruders. Total power, motor power, and melt temperature profiles were analyzed in an industrial scale single-screw extruder. Moreover, the active power (AP), mass throughput, torque, and power factor were measured in a laboratory scale twin-screw extruder. The results confirmed that the specific energy consumption for both single and twin screw extruders tends to decrease with the processing speed. However, this action deteriorates the thermal stability of the melt regardless the nature of the polymer. Rheological characterization results showed that the viscosity of LDPE and PS exhibited a normal shear thinning behavior. However, PMMA presented a shear thickening behavior at moderate-to-high shear rates, indicating the possible formation of entanglements. Overall, the findings of this work confirm that the materials' rheology has an appreciable correlation with the energy consumption in polymer extrusion and also most of the findings are in agreement with the previously reported investigations. Therefore, further research should be useful for identifying possible correlations between key process parameters and hence to further understand the processing behavior for wide range of machines, polymers, and operating conditions.

Yes / In this work, we considered model-based simulation and optimisation of a medium scale brackish water desalination process. The mathematical model is validated using actual multistage RO plant data of Al- Hashemite University (Jordan). Using the validated model, the sensitivity of different operating parameters such as pump pressure, brackish water flow rate and seasonal water temperature (covering the whole year) on the performance indicators such as productivity, product salinity and specific energy consumption of the process is conducted. For a given feed flow rate and pump pressure, winter season produces less freshwater that in summer in line with the assumption that winter water demand is less than that in summer. With the soaring energy prices globally, any opportunity for the reduction of energy is not only desirable from the economic point of view but is an absolute necessity to meet the net zero carbon emission pledge by many nations, as globally most desalination plants use fossil fuel as the main source of energy. Therefore, the second part of this paper attempts to minimise the specific energy consumption of the RO system using model-based optimisation technique. The study resulted not only 19 % reduction in specific energy but also 4.46 % increase in productivity in a particular season of the year. For fixed product demand, this opens the opportunity for scheduling cleaning and maintenance of the RO process without having to consider full system shutdown.

As the world becomes more focused on sustainability, there is increasing pressure on steel-bearing companies to improve their energy efficiency and reduce their carbon footprint. The heat treatment process accounts for about 25% of SKF's energy consumption, and it aims to achieve decarbonized operations by 2030 and the supply chain by 2050. Therefore, improving the energy efficiency of the heat treatment process can have significant economic and environmental benefits for the company. This thesis project aimed to conduct an energy mapping of different heat treatment processes at SKF to develop a methodology and standard key performance indicator for establishing energy performance and ensuring comparability between installations and processes. Three heat treatment processes were studied: through hardening, location A; case carburizing, location B; and surface induction hardening, location C. A detailed methodology and guidelines for carrying out energy mapping were developed. A standard key performance indicator known as Specific Energy consumption in kWh/kg at a particular utilization in % was set for comparisons among different heat treatment processes. Regression analysis was used to normalize the results. On the same utilization level, case carburizing, location B consumes more energy than through hardening, location A. Surface induction hardening, location C consumes 90% less than others and is less dependent on utilization. The carbon intensity in g CO2-eq/kg for greenhouse gas scopes 1, 2 and 3 were also studied. Case carburizing, location B had the highest climate impact due to the coal-based electricity mix of the country. Hence, the future availability of renewable electricity is critical when switching from gas to electricity across factories in SKF.

Yes / Solar energy, amongst all renewable energies, has attracted inexhaustible attention all over the world as a supplier of sustainable energy. The energy requirement of major seawater desalination processes such as multistage flash (MSF), multi-effect distillation (MED) and reverse osmosis (RO) are fulfilled by burning fossil fuels, which impact the environment significantly due to the emission of greenhouse gases. The integration of solar energy systems into seawater desalination processes is an attractive and alternative solution to fossil fuels. This study aims to (i) assess the progress of solar energy systems including concentrated solar power (CSP) and photovoltaic (PV) to power both thermal and membrane seawater desalination processes including MSF, MED, and RO and (ii) evaluate the economic considerations and associated challenges with recommendations for further improvements. Thus, several studies on a different combination of seawater desalination processes of solar energy systems are reviewed and analysed concerning specific energy consumption and freshwater production cost. It is observed that although solar energy systems have the potential of reducing carbon footprint significantly, the cost of water production still favours the use of fossil fuels. Further research and development on solar energy systems are required to make their use in desalination economically viable. Alternatively, the carbon tax on the use of fossil fuels may persuade desalination industries to adopt renewable energy such as solar.

The purpose of this research was to observe the removal efficiency for copper (Cu), nickel (Ni), and zinc (Zn) using Electrocoagulation (EC) technique in a continuous flow reactor with a synthetic bilge water emulsion; and additionally, to discuss the operation cost of the treatment. The optimal configuration for EC treatment used combined electrodes, aluminum and carbon steel; flow rate of 1 L/min; effluent recycling and 7.5 amps; this optimal configuration achieved 99% of zinc removal efficiency, 70% of both, copper and nickel removal efficiency, and low operation costs. The current intensity did not have significance incidence on the removal efficiency. The analysis of cost per gram of removed contaminant indicated that nickel had an average cost of $1.95 per gram removed, zinc and copper had $0.60 and $0.88 per gram removed, respectively. To develop additional experiments with the EC reactor are required in order to optimize metal removal efficiency.

When an energy simulation is performed for buildings it generates in lower energy consumption than what is later measured. This can often be a problem because of the building regulations which have requirements on the specific energy consumption. What distinguishes the newly built care and nursing accommodation Furugården, the building that the study deals with, is that it is differs from the normal case by having a lower measured energy consumption than what was originally planned. This study aims to find out which parts of the building's technical systems and residents' behavior that contributes to the low energy demand by means of the building energy simulation program BV2, a survey and monitored energy consumption. It can be concluded that the users' behavior has a great impact on the building's low energy consumption. Their behaviors were determined by surveys. It is mainly the low hot tap water usage that contributes to the low energy.