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Anukam, A., Okoh, O., Mamphweli, S. & Berghel, J. (2018). A comparative analysis of the gasification performances of torrefied and untorrefied bagasse: Influence of feed size, gasifier design and operating variables on gasification efficiency. International Journal of Engineering & Technology, 7(2), 859-867
Open this publication in new window or tab >>A comparative analysis of the gasification performances of torrefied and untorrefied bagasse: Influence of feed size, gasifier design and operating variables on gasification efficiency
2018 (English)In: International Journal of Engineering & Technology, E-ISSN 2227-524X, Vol. 7, no 2, p. 859-867Article in journal (Refereed) Published
Abstract [en]

This study conducted a comparative assessment of the gasification performances of torrefied and untorrefied bagasse with emphasis on feed size, gasifier design and operating conditions that would influence gasification efficiency. Torrefaction greatly improved the characteristics of bagasse and had significant impact on its gasification performance. The gasifier design parameters studied were throat angle and throat diameter. Temperature of input air and feed input were the gasifier operating conditions examined in the course of the gasification processes of both torrefied and untorrefied bagasse. These parameters were considered the most critical operating parameters that affect gasifier performance and, correlation between the parameters was established in the course of gasification. The results obtained showed higher gasification efficiency for torrefied bagasse in comparison to untorrefied bagasse under varied conditions of gasification, which was attributed mainly to changes in the characteristics of the torrefied material.  

Place, publisher, year, edition, pages
Science Publishing Corporation, 2018
Keywords
Biomass, Sugarcane Bagasse, Torrefaction, Gasification, Efficiency, Computer Simulation.
National Category
Mechanical Engineering Civil Engineering
Research subject
Environmental and Energy Systems
Identifiers
urn:nbn:se:kau:diva-70365 (URN)10.14419/ijet.v7i2.8489 (DOI)
Available from: 2018-11-29 Created: 2018-11-29 Last updated: 2018-12-13Bibliographically approved
Frodeson, S., Henriksson, G. & Berghel, J. (2018). Pelletizing pure biomass substances to investigate the mechanical properties and bonding mechanisms. BioResources, 13(1), 1202-1222
Open this publication in new window or tab >>Pelletizing pure biomass substances to investigate the mechanical properties and bonding mechanisms
2018 (English)In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 13, no 1, p. 1202-1222Article in journal (Refereed) Published
Abstract [en]

Solid fuel for heating is an important product, and for sustainability reasons, it is important to replace nonrenewable fuels with renewable resources. This entails that the raw material base for pellet production has to increase. A broader spectrum of materials for pelleting involves variation in biomass substances. This variation, due to lack of knowledge, limits the possibilities to increase the pellet production using new raw materials. In this study, pellets were produced with a single pellet press from 16 different pure biomass substances representing cellulose, hemicellulose, other polysaccharides, protein, lignin, and extractives, and five different wood species, representing softwoods and hardwoods. All pellets were analyzed for the work required for compression and friction, maximum force needed to overcome the backpressure, pellet hardness, solid density, and moisture uptake. The results showed that the hardest pellets were produced from the group of celluloses, followed by rice xylan and larch arbinogalactan. The weakest pellets were from the group of mannans. Conclusions are that the flexible polysaccharides have a greater impact on the pelletizing process than previously known, and that the differences between xylan and glucomannan may explain the difference in the behavior of pelletizing softwoods and hardwoods.

Place, publisher, year, edition, pages
North Carolina State University, 2018
Keywords
Biomass pellets, Renewable energy, Single pellet press, Wood pellets, Biomass, Cellulose, Fuels, Hardwoods, Polysaccharides, Presses (machine tools), Softwoods, Wood, Bonding mechanism, Non-renewable fuels, Pellet hardness, Pellet production, Renewable energies, Renewable resource, Wood pellet, Pelletizing
National Category
Energy Systems Paper, Pulp and Fiber Technology
Research subject
Environmental and Energy Systems; Chemical Engineering
Identifiers
urn:nbn:se:kau:diva-66400 (URN)10.15376/biores.13.1.1202-1222 (DOI)2-s2.0-85041345528 (Scopus ID)
Note

Export Date: 16 February 2018; Article; Correspondence Address: Frodeson, S.; Environmental and Energy Systems, Department of Engineering and Chemical Science, Karlstad University, KarlstadSweden; email: Stefan.Frodeson@kau.se; References: Ahn, B.J., Chang, H.-S., Lee, S.M., Choi, D.H., Cho, S.T., Han, G.-S., Yang, I., 'Effect of binders on the durability of wood pellets fabricated from Larix kaemferi C. and Liriodendron tulipifera L. sawdust, ' (2014) Renew. Energ, 62, pp. 18-23; Barsett, H., Ebringerová, A., Harding, S., Heinze, T., Hromádková, Z., Muzzarelli, C., Muzzraelli, R., El Seoud, O., (2005) Polysaccharides I: Structure, , Characterisation and Use, Springer Science & Business Media, Berlin, Germany; Berghel, J., Frodeson, S., Granström, K., Renström, R., Ståhl, M., Nordgren, D., Tomani, P., 'The effects of kraft lignin additives on wood fuel pellet quality, energy use and shelf life, ' (2013) Fuel Process. Technol, 112, pp. 64-69; Berglund, J., Angles d'Ortoli, T., Vilaplana, F., Widmalm, G., Bergenstråhle-Wohlert, M., Lawoko, M., Henriksson, G., Wohlert, J., 'A molecular dynamics study of the effect of glycosidic linkage type in the hemicellulose backbone on the molecular chain flexibility, ' (2016) The Plant Journal, 88 (1), pp. 56-70; Braccini, I., Pérez, S., 'Molecular basis of Ca2+-induced gelation in alginates and pectins: The egg-box model revisited, ' (2001) Biomacromolecules, 2 (4), pp. 1089-1096; Christiansen, A.W., 'How overdrying wood reduces its bonding to phenol-formaldehyde adhesives: A critical review of the literature. 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J, 38 (1), pp. 52-56; Irvine, G., 'The glass transitions of lignin and hemicellulose and their measurement by differential thermal analysis, ' (1984) Tappi J, 67 (5), pp. 118-121; Kaliyan, N., Morey, R.V., 'Natural binders and solid bridge type binding mechanisms in briquettes and pellets made from corn stover and switchgrass, ' (2010) Bioresource Technol, 101 (3), pp. 1082-1090; Kaliyan, N., Morey, R.V., 'Factors affecting strength and durability of densified biomass products, ' (2009) Biomass Bioenerg, 33 (3), pp. 337-359; Kuokkanen, M.J., Vilppo, T., Kuokkanen, T., Stoor, T., Niinimäki, J., 'Additives in wood pellet production-A pilot-scale study of binding agent usage, ' (2011) BioResources, 6 (4), pp. 4331-4355; Lawoko, M., Berggren, R., Berthold, F., Henriksson, G., Gellerstedt, G., 'Changes in the lignin-carbohydrate complex in softwood kraft pulp during kraft and oxygen delignification, ' (2004) Holzforschung, 58 (6), pp. 603-610; Mani, S., Tabil, L.G., Sokhansanj, S., 'Compaction of biomass grinds-An overview of compaction of biomass grinds, ' (2003) Powder Handling and Processing, 15 (3), pp. 160-168; Mani, S., Tabil, L.G., Sokhansanj, S., 'Effects of compressive force, particle size and moisture content on mechanical properties of biomass pellets from grasses, ' (2006) Biomass Bioenerg, 30 (7), pp. 648-654; Mišljenovic, N., Colovic, R., Vukmirovic, D., Brlek, T., Bringas, C.S., 'The effects of sugar beet molasses on wheat straw pelleting and pellet quality. A comparative study of pelleting by using a single pellet press and a pilot-scale pellet press, ' (2016) Fuel Process. Technol, 144, pp. 220-229; Nguyen, Q.N., Cloutier, A., Achim, A., Stevanovic, T., 'Effect of process parameters and raw material characteristics on physical and mechanical properties of wood pellets made from sugar maple particles, ' (2015) Biomass Bioenerg, 80, pp. 338-349; Nielsen, N.P.K., (2009) Importance of Raw Material Properties in Wood Pellet Production: Effects of Differences in Wood Properties for the Energy Requirements of Pelletizing and the Pellet Quality, , Ph.D. Dissertation, University of Copenhagen, Copenhagen, Denmark; Nielsen, N.P.K., Gardner, D.J., Felby, C., 'Effect of extractives and storage on the pelletizing process of sawdust, ' (2010) Fuel, 89 (1), pp. 94-98; Nielsen, N.P.K., Gardner, D.J., Poulsen, T., Felby, C., 'Importance of temperature, moisture content, and species for the conversion process of wood residues into fuel pellets, ' (2009) Wood Fiber Sci, 41 (4), p. 414; Nielsen, N.P.K., Holm, J.K., Felby, C., 'Effect of fiber orientation on compression and frictional properties of sawdust particles in fuel pellet production, ' (2009) Energ. Fuel, 23 (6), pp. 3211-3216; Pauly, M., Keegstra, K., 'Cell-wall carbohydrates and their modification as a resource for biofuels, ' (2008) The Plant Journal, 54 (4), pp. 559-568; Pettersen, R.C., 'The chemical composition of wood, ' (1984) The Chemistry of Solid Wood, Advances in Chemistry Series, 207, pp. 57-126. , in: R. M. Rowell (ed.) Washington DC, American Chemical Society; Puig-Arnavat, M., Shang, L., Sárossy, Z., Ahrenfeldt, J., Henriksen, U.B., 'From a single pellet press to a bench scale pellet mill-Pelletizing six different biomass feedstocks, ' (2016) Fuel Process. Technol, 142, pp. 27-33; Ramírez-Gómez, A., 'Research needs on biomass characterization to prevent handling problems and hazards in industry, ' (2016) Particul. Sci. Technol, 34 (4), pp. 432-441; Roffael, E., 'Significance of wood extractives for wood bonding, ' (2016) Applied Microbiology and Biotechnology, 100 (4), pp. 1589-1596; Rumpf, H., 'The strength of granules and agglomerate, ' (1962) Agglomeration, pp. 379-418. , W. A. Knepper (ed.), Interscience Publishers, New York, NY; Rydholm, S.A., (1985) Pulping Processes, , Robert Krieger Publishing Co., Inc., Malabar, FL 32950; Samuelsson, R., Larsson, S.H., Thyrel, M., Lestander, T.A., 'Moisture content and storage time influence the binding mechanisms in biofuel wood pellets, ' (2012) Appl. Energ, 99, pp. 109-115; Samuelsson, R., Thyrel, M., Sjöström, M., Lestander, T.A., 'Effect of biomaterial characteristics on pelletizing properties and biofuel pellet quality, ' (2009) Fuel Process. Technol, 90 (9), pp. 1129-1134; (2009) 'Solid biofuels-Determination of moisture content-Oven dry method-Part 1: Total moisture-Reference method, ', , Swedish Standards Institute, Stockholm, Sweden; Stelte, W., Holm, J.K., Sanadi, A.R., Barsberg, S., Ahrenfeldt, J., Henriksen, U.B., 'Fuel pellets from biomass: The importance of the pelletizing pressure and its dependency on the processing conditions, ' (2011) Fuel, 90 (11), pp. 3285-3290; Stelte, W., Holm, J.K., Sanadi, A.R., Barsberg, S., Ahrenfeldt, J., Henriksen, U.B., 'A study of bonding and failure mechanisms in fuel pellets from different biomass resources, ' (2011) Biomass Bioenerg, 35 (2), pp. 910-918; Stelte, W., Sanadi, A.R., Shang, L., Holm, J.K., Ahrenfeldt, J., Henriksen, U.B., 'Recent developments in biomass pelletization-A review, ' (2012) BioResources, 7 (3), pp. 4451-4490; Ståhl, M., Berghel, J., Frodeson, S., Granström, K., Renström, R., 'Effects on pellet properties and energy use when starch is added in the wood-fuel pelletizing process, ' (2012) Energ. Fuel, 26 (3), pp. 1937-1945; Ståhl, M., Berghel, J., Granström, K., 'Improvement of wood fuel pellet quality using sustainable sugar additives, ' (2016) BioResources, 11 (2), pp. 3373-3383; Tarasov, D., Shahi, C., Leitch, M., 'Effect of additives on wood pellet physical and thermal characteristics: A review, ' (2013) ISRN Forestry, 2013, pp. 1-6; Vassilev, S.V., Baxter, D., Andersen, L.K., Vassileva, C.G., 'An overview of the chemical composition of biomass, ' (2010) Fuel, 89 (5), pp. 913-933; Whittaker, C., Shield, I., 'Factors affecting wood, energy grass and straw pellet durability-A review, ' (2017) Renew. Sust. Energ. Rev, 71, pp. 1-11

Available from: 2018-02-16 Created: 2018-02-16 Last updated: 2018-04-16
Mattsson, L., Williams, H. & Berghel, J. (2018). Waste of fresh fruit and vegetables at retailers in Sweden: Measuring and calculation of mass, economic cost and climate impact. Resources, Conservation and Recycling, 130, 118-126
Open this publication in new window or tab >>Waste of fresh fruit and vegetables at retailers in Sweden: Measuring and calculation of mass, economic cost and climate impact
2018 (English)In: Resources, Conservation and Recycling, ISSN 0921-3449, E-ISSN 1879-0658, Vol. 130, p. 118-126Article in journal (Refereed) Published
Abstract [en]

Food waste is a significant problem for environmental, economic and food security reasons. The retailer, food service and consumers have been recognised as the parts of the food supply chain where the possibility of reducing food waste is greatest in industrialised countries. In this study, primary data on fresh fruit and vegetables (FFV) waste collected through direct measurements in three large retail stores in Sweden were analysed from the perspectives of wasted mass, economic cost and climate impact. A method of measuring and calculating the economic cost of FFV waste was developed and includes the cost of wasted produce, the cost of personnel time for waste management and the cost of waste collection and disposal. The results show that seven FFV categories, which have been termed "hotspot categories", contributed to the majority of the waste, both in terms of wasted mass, economic cost and climate impact. The "hotspot categories" are apple, banana, grape, lettuce, pear, sweet pepper, and tomato. The cost benefit analysis conducted showed that it is economically wise to invest in more working time for employees in waste management to accomplish a reduction of wasted mass and climate impact without an economic loss for the store. These results are relevant for supporting the implementation of policies and initiatives aimed at food waste reduction at retail level.

National Category
Environmental Engineering
Research subject
Environmental and Energy Systems
Identifiers
urn:nbn:se:kau:diva-66185 (URN)10.1016/j.resconrec.2017.10.037 (DOI)000423005400016 ()
Available from: 2018-02-09 Created: 2018-02-09 Last updated: 2018-04-05Bibliographically approved
Ottosson, A., Nilsson, L. & Berghel, J. (2017). A mathematical model of heat and mass transfer in Yankee drying of tissue. Drying Technology, 35(3), 323-334
Open this publication in new window or tab >>A mathematical model of heat and mass transfer in Yankee drying of tissue
2017 (English)In: Drying Technology, ISSN 0737-3937, E-ISSN 1532-2300, Vol. 35, no 3, p. 323-334Article in journal (Refereed) Published
Abstract [en]

Final dewatering in the production of dry creped tissue is performed by Yankee drying, which includes hot pressing followed by simultaneous contact and impingement drying. The present study models Yankee drying and compares simulation results to the data obtained from trials on a pilot tissue machine. It advances models published previously by the representations developed for the transport of heat in the pressing stage and for the heat transfer involved in the dehydration of the cylinder coating spray. The model predicts an average specific drying rate within 4% in the range of the experimental data used.

Place, publisher, year, edition, pages
Taylor & Francis, 2017
Keywords
Heat and mass transfer, mathematical model, tissue drying
National Category
Energy Engineering
Identifiers
urn:nbn:se:kau:diva-63896 (URN)10.1080/07373937.2016.1170697 (DOI)000395033700006 ()
Available from: 2017-09-22 Created: 2017-09-22 Last updated: 2018-06-25Bibliographically approved
Ståhl, M., Berghel, J. & Frodeson, S. (2017). Research Experience From The Use Of Different Additives In Wood-Fuel Pellet Production. International Journal of Energy Production and Management, 2(3), 288-293
Open this publication in new window or tab >>Research Experience From The Use Of Different Additives In Wood-Fuel Pellet Production
2017 (English)In: International Journal of Energy Production and Management, ISSN 2056-3272, E-ISSN 2056-3280, Vol. 2, no 3, p. 288-293Article in journal (Refereed) Published
Abstract [en]

The use of wood-fuel pellets has increased signi cantly worldwide in recent years, especially in the United Kingdom. If wood-fuel pellets should continue to be a successful biofuel at the energy market, the pellet production industry has to reduce the production cost, since it is a low-margin business. Further, improved pellets regarding storability and strength of the pellets are crucial to manage the overseas transportation that causes material losses. In addition, the industry tries to produce pellets from a broader raw material base and at the same time satisfy the customer requirements while produc- ing a sustainable product. The wood-fuel pellet industry has the possibility to meet all these criteria; however, it also has the potential for improvements. Using additives in pellet production is one way to meet the criteria. In conclusion, it is necessary to do the research that systematically investigates the consequences of using additives for wood-fuel pellets, and this work presents a compilation of results and experiences from more than 20 different additive studies and the test bed for pellet produc- tion research at Karlstad University– a pellet production unit adapted for additives studies. Additives, with an admixture of up to 2% (wt.), have been tested in the NewDeP (New Development for Pellet Technology) pilot plant for pellet production at Karlstad University. The research has focused on the electricity consumption, the physical and mechanical properties of the pellets, and the CO2 equivalents emitted during production. The results showed that the additives Wetland grass, Algae, Turpentine and Lignin decreased the electricity consumption in the pellet press but unfortunately also decreased the durability. The additives Resins, Molasses, White sugar, Native potato starch and Oxidized potato starch increased the durability of the pellet but showed almost no change in the electricity consumption. However, Oxidized corn starch, Spent sulphite liquor and Native wheat starch as additives increased the mechanical properties while it decreases both the electricity consumption and the climate impact, hence a Win-Win-Win situation. 

Place, publisher, year, edition, pages
WIT Press, 2017
Keywords
additives, CO2 equivalents, durability, electricity consumption, wood-fuel pellets
National Category
Energy Engineering
Research subject
Environmental and Energy Systems
Identifiers
urn:nbn:se:kau:diva-70043 (URN)10.2495/EQ-V2-N3-288-293 (DOI)
Available from: 2018-11-06 Created: 2018-11-06 Last updated: 2018-11-07Bibliographically approved
Berghel, J., Ståhl, M. & Frodeson, S. (2017). The amount of dust and rejects as well as the electricity consumption during production decreases with the use of adequate additives. In: : . Paper presented at International Biomass and Conference & Expo, Minneapolis, Minnesota, USA. 10-12 April 2017.
Open this publication in new window or tab >>The amount of dust and rejects as well as the electricity consumption during production decreases with the use of adequate additives
2017 (English)Conference paper, Oral presentation only (Other academic)
National Category
Energy Engineering
Research subject
Environmental and Energy Systems
Identifiers
urn:nbn:se:kau:diva-63905 (URN)
Conference
International Biomass and Conference & Expo, Minneapolis, Minnesota, USA. 10-12 April 2017
Available from: 2017-09-22 Created: 2017-09-22 Last updated: 2018-06-26Bibliographically approved
Ståhl, M., Berghel, J. & Frodeson, S. (2016). Additives for wood fuel pellet production - A win, win, win situation. In: : . Paper presented at 6th International Symposium "Energy challenges & mechanics - towards a big picture", Inverness, Scotland. 14-18 august 2016.
Open this publication in new window or tab >>Additives for wood fuel pellet production - A win, win, win situation
2016 (English)Conference paper, Oral presentation with published abstract (Other academic)
Abstract [en]

The production and use of wood-fuel pellets, preferably made from sawdust or shavings, have increased significantly worldwide in recent years. If wood-fuel pellets should continue to be a successful biofuel at the energy market there are several factors to take into consideration. The pellet production industry already tries to reduce the production cost, since it is a low margin business. Further, it tries to produce pellets from a broader raw material base and at the same time satisfy the customer requirements while producing a sustainable product. The wood fuel pellet industry has the possibility to meet all these criteria; however, it also has the potential for improvements.

This work focuses on energy efficiency, technical aspects and environmental factors, i.e., the electricity consumption, the physical and mechanical properties of the pellets, and the CO

2 equivalent emitted during production, respectively. 20 various additives, with an admixture of up to 2 % (wt.), have been tested during wood fuel pellet production at Karlstad University. This work presents the benefits of using different additives in pellet production and the cost associated with different additives. The results shows that additive from the sea and from farmlands (algae, rape seed cake and grass) decrease the energy use in the pellet press but unfortunately also decrease the durability. Additives from wood (resins, lignin) and molasses increases the durability of the pellet but shows almost no or little change in electricity consumption. However, using starch grades, white sugar or spent sulphite liquor as an additive increases the mechanical properties while it decreases both the electricity consumption and the climate impact, hence a win-win-win situation. To justify the use of additives from a climate impact perspective in regions with an OECD European electricity mix or the Swedish electricity mix, the usage of additives from the rest products where the CO2 equivalent emissions are allocated to the main product are crucial.

In conclusion, it is necessary to do research that systematically investigates the consequences of using additives for wood fuel pellets to continuously be a successful biofuel at the energy market

National Category
Energy Engineering Energy Systems Bioenergy
Identifiers
urn:nbn:se:kau:diva-63906 (URN)
Conference
6th International Symposium "Energy challenges & mechanics - towards a big picture", Inverness, Scotland. 14-18 august 2016
Available from: 2017-09-22 Created: 2017-09-22 Last updated: 2018-07-09Bibliographically approved
Stahl, M., Berghel, J. & Granstrom, K. (2016). Improvement of Wood Fuel Pellet Quality Using Sustainable Sugar Additives. BioResources, 11(2), 3373-3383
Open this publication in new window or tab >>Improvement of Wood Fuel Pellet Quality Using Sustainable Sugar Additives
2016 (English)In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 11, no 2, p. 3373-3383Article in journal (Refereed) Published
Abstract [en]

The global production and use of wood fuel pellets has increased significantly in recent years. The raw material and the energy required to dry it are the main production costs. Therefore, it is crucial to minimize energy consumption, production costs, and the environmental impact associated with wood pellets. However, these changes should not negatively affect the quality of the pellets. One way to achieve these goals is to use additives. This work investigates how different types of sugar additives affect both the energy needed by the pellet press and the durability and oxidation of the produced pellets. When sugar was used as an additive, the energy use was practically unaffected. When molasses and SSL were added, a small decrease in energy use was observed (6 to 8%) for admixtures up to 1 wt.%; however, when more molasses was added, the energy use increased. Using these additives increased the bulk density (7 to 15 %) and durability (10 to 20 %) of the pellets. The storage of the pellets also caused a small increase in durability (1 to 3 %). Volatile organic compounds were produced as oxidation peaks within the first two months of storage; thereafter, the peaks tapered off.

Keywords
Wood fuel pellet, Additives, Molasses, White sugar, Spent sulphite liquor, Energy efficiency, Durability, Storage
National Category
Paper, Pulp and Fiber Technology
Research subject
Environmental and Energy Systems
Identifiers
urn:nbn:se:kau:diva-44549 (URN)000375786700031 ()
Available from: 2016-08-04 Created: 2016-08-04 Last updated: 2017-12-06Bibliographically approved
Bengtsson, P. & Berghel, J. (2016). Study of using a capillary tube in a heat pump dishwasher with transient heating. International journal of refrigeration, 67, 1-9
Open this publication in new window or tab >>Study of using a capillary tube in a heat pump dishwasher with transient heating
2016 (English)In: International journal of refrigeration, ISSN 0140-7007, E-ISSN 1879-2081, Vol. 67, p. 1-9Article in journal (Refereed) Published
Abstract [en]

For competitive purposes, manufacturers of household appliances need to produce appliances that use less electricity. One way of doing this for a dishwasher is to add a heat pump system. Previous studies using R134a as refrigerant have shown that the addition of a heat pump can reduce total electricity consumption by about 24%. This paper reports on the use of a capillary tube in a heat pump dishwasher during the transient heating period. Working with an available compressor, the mass of R600a and the length of a 0.9 mm capillary tube were varied in order to find the configuration with the lowest electricity consumption. Three methods of calculating the length of the capillary tube were used to determine five lengths for evaluation. The results show that using a single capillary tube throughout the transient heating period yields similar electricity consumption to a variable expansion device which occurred by switching the capillary tube between two or three different lengths during the heating period.

Place, publisher, year, edition, pages
Elsevier, 2016
Keywords
Home appliances, Expansion device, Environmental impact, Natural refrigerant, Energy use
National Category
Energy Systems
Research subject
Energy Technology
Identifiers
urn:nbn:se:kau:diva-44653 (URN)10.1016/j.ijrefrig.2016.04.006 (DOI)000378951900002 ()
Available from: 2016-08-11 Created: 2016-08-11 Last updated: 2017-12-06Bibliographically approved
Bengtsson, P., Berghel, J. & Renström, R. (2015). A household dishwasher heated by a heat pump system using an energy storage unit with water as the heat source. International journal of refrigeration, 49, 19-27
Open this publication in new window or tab >>A household dishwasher heated by a heat pump system using an energy storage unit with water as the heat source
2015 (English)In: International journal of refrigeration, ISSN 0140-7007, E-ISSN 1879-2081, Vol. 49, p. 19-27Article in journal (Refereed) Published
Abstract [en]

Electricity usage by a household dishwasher can be reduced by using a heat pump system to heat the dishwasher cabinet, dishware and washing water. The evaporator obtains the energy from an energy storage unit which consists of a container filled with water which freezes to ice. The majority of the heat transfer from the energy storage to the evaporator occurs when ice is created in the energy storage unit. A transient simulation model of a dishwasher with a heat pump system was developed and compared to an experimental setup with good agreement. A simulation study of the compressor cylinder volume and the compressor operating time was performed. The results showed a 24% reduction in total electricity use compared to a dishwasher cycle using a traditional electric element.

Place, publisher, year, edition, pages
Elsevier, 2015
Keywords
Appliances, Energy use, Heat transfer, Freezing, Transient simulation, Appareils domestiques, Utilisation d'énergie, Transfert de chaleur, Congélation, Simulation transitoire
National Category
Energy Engineering
Research subject
Environmental and Energy Systems
Identifiers
urn:nbn:se:kau:diva-39072 (URN)10.1016/j.ijrefrig.2014.10.012 (DOI)000348012500004 ()
Funder
Knowledge Foundation
Available from: 2016-01-19 Created: 2016-01-19 Last updated: 2017-11-30Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-9707-8896

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