| 1. |
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| 2. |
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| 3. |
- Andersson, Eva Ingeborg Elisabeth, 1956, et al.
(författare)
-
Pinch analysis at Preem LYR
- 2013
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This energy inventory and pinch analysis of the Preem, Lysekil refinery is a part of the Preem – Chalmers research cooperation and has been carried out by CIT Industriell Energi AB. The result in this report will be used as a basis for the research work at Chalmers.The aim with the project is to supply the researchers at Chalmers with energy data from the refinery in a form that is suitable for different types of pinch analysis. Furthermore, the aim is to make an analysis to establish the possible energy saving potentials in the refinery at various levels of process integration constraints.To be able to perform a pinch analysis, data for process streams has to be collected. This has been made using material received from Preem. Stream data has been extracted for all streams that have been identified on the process flow diagrams for all units of the refinery. Service areas and tank farm is not included.The stream data extraction is documented in a file. For each stream there is a calculation area with the information gathered to explain the choice of data used as stream data for the individual stream. Calculation of stream load is made by using known data of flow and physical data. If necessary data is not available from the screen dumps, data has been estimated. For the most important data, process engineers at Preem have been involved to give background information and assistance to find the best estimation possible.The refinery has a net heat demand of 409 MW (for the operation case studied) which is supplied by firing fuel gas. Steam is generated in the process by cooling process streams. One part of this steam (167 MW) is used in the process and the remainder(17 MW) is expanded in turbines and used for other purposes.The energy saving potential, i.e. the theoretical savings that are achievable depend on the constraints that are put on the heat exchanging between process streams in the refinery. Three levels have been analysed.A: There are no restrictions on the process streams that may be heat exchanged in the refinery. In this case the minimum heat demand is 199 MW giving a theoretical savings potential of 210 MW.B: All streams within each process unit can be exchanged with each other, but heat exchange between process units is not permitted. In this case the minimum heat demand of each process unit must be calculated. Some of the identified pinch violations are impossible to eliminate, due to process constraints, and the minimum heat demand is thus corrected to reflect this. The total savings potential, 140 MW, is calculated by adding the savings potential for the separate units. However only a part II of the steam generated above the pinch can be eliminated since it is used for heating purposes in other process units. Only the steam surplus can be considered a savings potential and the total potential is reduced to 117 MW.C: Heat exchange between process units is allowed for those streams which are heat exchanged with utility today (e.g., steam, air, cooling water). The heat exchange takes place with the aid of one or more utility system. However, it is not allowed to modify existing process to process heat exchangers to improve heat exchange between process units. The scope of the analysis is limited by only looking at the 5 largest process units. This group of units are using ~90 %, 363 MW, of the added external heat. If heat from the flue gases is recovered at a higher temperature it is possible to reduce the external heat demand with 26 MW to 337 MW.
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| 4. |
- Andersson, Eva Ingeborg Elisabeth, 1956, et al.
(författare)
-
TSA II Stenungsund - Investigation of opportunities for implementation of proposed energy efficiency measures
- 2011
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- A Total Site Analysis (TSA) study of the chemical cluster in Stenungsund was conducted during 2010. This previous study is hereafter referred to as the TSA I study. The study was conducted by CIT Industriell Energi and the Division of Heat and Power Technology at Chalmers together with the participating cluster companies (AGA Gas AB, Akzo Nobel Sverige AB, Borealis AB, INEOS Sverige AB and Perstorp Oxo AB).In the TSA I study, measures to increase energy efficiency by increased energy collaboration (i.e. increased heat exchange between the cluster plants) were identified. The measures were classified according to ease of implementation based on consultation with plant staff. In this report, conducted within the framework of the second stage of the TSA research project (hereafter referred to as the TSA II project) practical issues associated with implementation of the identified measures are investigated. The investigation is limited to category A measures, considered by plant staff to be relatively easy to implement from a technical perspective. A conceptual design of a possible hot water system for exchanging heat between the different sites is presented. Since the steam systems of the different plants are at present only partly connected, or not at all, the overall reduction in steam use that would results from introduction of a hot water system would lead to steam surplus at certain sites. Therefore introducing a hot water system is only beneficial if new steam lines are also implemented so that it becomes possible to exchange steam between the individual plant sites. The exchange of steam is only possible if steam demand and steam excess are at the same pressure level. To avoid excess steam at low pressure level, demand of low pressure steam must increase. In order to increase the possibility to use more low pressure steam, the opportunities to decrease utility steam pressure in individual process heaters are analyzed. The implementation of energy efficiency measures in the refrigeration systems is also investigated. In practice this can be achieved by changing steam as heating utility to a fluid that can operate below ambient. In addition to the steam saving, the heat transfer fluid can transport energy from the current cooling systems and decrease the amount of compressor work required to operate the existing refrigeration system units.In order to achieve a reduction of purchased fuel for firing in boilers it is necessary to implement both a common site-wide circulating hot water system and a reduction of utility steam pressure used in several process heaters .The results show that if all measures that are considered by plant energy engineers to be feasible by moderate changes are carried out as suggested, fuel usage in boilers could be reduced by 89 MW (corresponding to 200 MSEK/year if fuel gas is valued at 270 SEK/MWh and year-round operation is assumed).A rough estimate of the total investment costs for the implementation of category A measures is 660 MSEK.
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| 5. |
- Andersson, Viktor, 1983, et al.
(författare)
-
Efficient Utilization of Industrial Excess Heat for Post-combustion CO2 Capture: An Oil Refinery Sector Case Study
- 2014
-
Ingår i: Energy Procedia. - : Elsevier BV. - 1876-6102. ; 63, s. 6548-6556
-
Konferensbidrag (refereegranskat)abstract
- A key issue in post-combustion carbon capture is the choice of absorbent. In this paper two different absorbents, monoethanolamine (MEA) and ammonia (NH3), have been modeled in Aspen Plus at different temperatures for possible implementation at an oil refinery. The focus of investigation is the possibilities of heat integration between the oil refinery and the carbon capture process and how these possibilities could change in a future situation where energy efficiency measures have been implemented.The results show that if only using excess heat from the refinery for heating of the carbon capture process, the MEA process can capture more CO2 than the NH3 process. It is shown that the configuration requiring least supplementary heat when applying carbon capture to all flue gases is MEA at 120 °C.The temperature profile of the excess heat from the refinery suits the MEA and NH3 processes differently. The NH3 process would benefit from a flat section above 100 °C to better integrate the heat needed to reduce slip, while the MEA process only needs heat at stripper temperature.
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| 6. |
- Andersson, Viktor, 1983, et al.
(författare)
-
Industrial excess heat driven post-combustion CCS: The effect of stripper temperature level
- 2014
-
Ingår i: International Journal of Greenhouse Gas Control. - : Elsevier BV. - 1750-5836. ; 21, s. 1-10
-
Tidskriftsartikel (refereegranskat)abstract
- The implementation of post-combustion CCS provides an opportunity for the oil refining sector to drastically decrease its CO2 emissions. Previous studies have shown that the largest cost is the heat supply to the stripper reboiler. When performing CCS at an oil refinery it could therefore prove economically beneficial to utilize the excess heat from refinery processes to meet this demand for heat. The present study investigates the heat demand in a stripper reboiler at different temperature levels from 120 degrees C down to 90 degrees C. At temperatures lower than 120 degrees C the heat demand increases, but the availability of excess heat also increases. A case study that connects heat demand results with data from an oil refinery shows that if only excess heat is utilized as a heat source, the amount of CO2 that can be separated is largest when the temperature in the stripper reboiler is 90 degrees C. If, however, CCS with a capture rate of 85% were applied to the four largest chimneys at the refinery, the external heat demand would be the lowest for the standard temperature of 120 degrees C. (C) 2013 Elsevier Ltd. All rights reserved.
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| 7. |
- Andersson, Viktor, 1983, et al.
(författare)
-
Techno-economic analysis of excess heat driven post-combustion CCS at an oil refinery
- 2016
-
Ingår i: International Journal of Greenhouse Gas Control. - : Elsevier BV. - 1750-5836. ; 45, s. 130-138
-
Tidskriftsartikel (refereegranskat)abstract
- Carbon capture and storage may, as a bridging technology, rapidly decrease CO2 emissions in the industrial sector. In this paper, a techno-economic study of a future MEA carbon capture plant implemented at a case study oil refinery is presented. Costs are calculated for six setups of carbon capture at the refinery. Excess heat from the refinery processes is used in the capture plant for regeneration of the absorption fluid, and the stripper reboiler temperature is varied to increase the extractable of excess heat. Supplementary heating is carried out with a heat pump. The number of chimneys to be included in the capture process is also varied, resulting in different CO2 concentrations and amounts of CO2 at the inlet of the capture plant. Results show that the specific cost for carbon capture increases as the amount of captured carbon increases due to the need for heat pumps. The costs are in the range of 41-57(sic)/t for the low-temperature cases (T-Reb =90 degrees C) and 39-44(sic)/t for the high-temperature cases (T-Reb = 120 degrees C).
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| 8. |
- Andersson, Viktor, 1983, et al.
(författare)
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Temperature Dependence of Heat Integration Possibilities of an MEA Scrubber Plant at a Refinery
- 2013
-
Ingår i: Energy Procedia. - : Elsevier BV. - 1876-6102. ; 37, s. 7205-7213
-
Konferensbidrag (refereegranskat)abstract
- A study has been conducted in order to investigate how the specific heat requirements in the stripper reboiler of a MEA capture plant changes with changing temperature. It was found that the increase in heat demand is dramatic when lowering the temperature, approximately 40% when the temperature changes from 120 to 90° C. Heat integration with a refinery was also studied, and showed that even if the heat demand was larger for the lower temperature the heat integration possibilities were also larger for the base case.
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| 9. |
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| 10. |
- Berntsson, Thore, 1947, et al.
(författare)
-
Learning from experiences with Industrial Heat Pumps
- 1997
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This publication is the twenty-third in a series of Analysis Reports. These reports are specifically designed to increase awareness of a particular energy-saving technology or technique, applicable in the end-use sector, thereby facilitating its market introduction. The reports are designed to inform end-users of the characteristics of suecessful applications, and also to indicate those aspects requiring detailed assessment prior to implementation.
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| 11. |
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| 12. |
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| 13. |
- Berntsson, Thore, 1947, et al.
(författare)
-
Towards Sustainabel Oil Refinery - Pre-study for larger co-operation project
- 2008
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In this report, the Chalmers EnergiCentrum (CEC) presents the results of a pre-study commissioned by Preem relating to the effective production of future vehicle fuels.This pre-study was made up of three studies focusing on energy streamlining, the utilisation of waste heat and carbon-dioxide separation and biorefinement relating to the gasification and hydration of vegetable oils. One of the common starting points for these studies was the current situation at the Preem refineries in Göteborg and Lysekil from where the measurement data were obtained and analysed. The report summarises the knowledge situation based on current research in the individual technical fields. The results present some interesting future opportunities for developing the sustainable production of future vehicle fuels. The sections vary, as the areas that have been examined differ and the sections have been written by different people. The reports ends with some joint conclusions and a number of questions which could be included and answered in a more extensive future main study, as part of a developed research partnership between Preem and the Chalmers University of Technology. The preliminary results of this work were analysed with the client at workshops on 1 October and 29 November 2007. The report is written in English combined with an extensive summary in Swedish including a proposal on a future main study. The study was conducted by the Chalmers EnergiCentrum (CEC), in collaboration with a number of researchers in the CEC’s network. They included Thore Berntsson, Jessica Algehed, Erik Hektor and Lennart Persson Elmeroth, all from Heat and Power Technology, Börje Gevert, Chemical and Biological Engineering, Tobias Richards, Forest Products and Chemical Engineering, Filip Johnsson and Anders Lyngfelt, Energy Technology, and Per-Åke Franck and Anders Åsblad, CIT Industriell Energianalys AB. The client, Preem, was represented by Bengt Ahlén, Sören Eriksson, Johan Jervehed, Bertil Karlsson, Gunnar Olsson, Ulf Kuylenstierna, Stefan Nyström, Martin Sjöberg and Thomas Ögren. Tobias Richards was responsible for compiling the report and Bertil Pettersson was the project manager.
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| 14. |
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| 15. |
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| 16. |
- Carlsson, Annika, 1965, et al.
(författare)
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Retrofit of heat exchanger networks
- 1991
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Ingår i: Föredrag vid 1992 IChem Research Event, University of Manchester, England, 9-10 januari, 1992.
-
Konferensbidrag (refereegranskat)
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| 17. |
- Eriksson, Karin, 1976, et al.
(författare)
-
Pre-study on the establishment of a research collaboration between industrial energy systems and process control at Chalmers
- 2013
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The aim of the project described in this report has been to create a platform for collaboration between the research areas of industrial energy systems and process control at Chalmers. The authors of this report, belonging to the division of Heat and Power Technology, the Automatic control group and to CIT Industriell Energi, are convinced that a close collaboration between these areas could generate benefits for the process industry including •Improved efficiency with respect to energy•Improved opportunities to ensure satisfying operability•Improved process stability and product uniformity•Intensified utilization of available process equipment•Increased profitabilityIn accordance with the project scope, an inventory of relevant academic literature and of past and ongoing activities within the relevant research community has been conducted. Firstly, this inventory recognizes that researchers at Lehigh University (US), NTNU (Norway) and Carnegie Mellon University (US) have been strongly involved in the establishment of a research field commonly referred to as Integrated design and control. It is found that the research questions that are in the interest of the project partners largely can be attributed to this field. Other related labels used, and investigated as part of the project, are plant-wide control and heat exchanger network control. In a specific section of the report, definitions of important terms like operability, controllability and flexibility are given and commented on. Secondly, international research groups of special interest that has been identified are presented. In this category, I2C2 at University of Auckland and CAPEC at Technical University of Denmark can be mentioned. Relevant publications of the above mentioned research groups and their associates have been studied and are commented on in the report. Special emphasize has been put on review papers and on recent publications. Furthermore, the project has mapped the competences, experience and interest of the project partners. On this basis, the following keywords were identified:•Retrofit•Bio-based processes•Pulp and paper industry•Real life case studies•Industrial co-operation•Economic evaluation•Simulation•Scale up challengesThis list was used during discussions on research questions and project ideas for future collaboration. This project has provided the partners an opportunity to obtain deeper insight into each other’s knowledge and experiences, and, moreover, research areas of common interest have been recognized. To further develop the collaboration, the next step seems to imply joint participation in specific research projects. Research questions of interest and ideas for future projects are presented in the full report. This relates to the prevailing possibilities to apply for research grant - an issue that is addressed lastly in this report. In relation to this it should be noted that there is a program on Industrial Process Automation, supported by Vinnova, the Swedish Energy Agency and Formas, that is soon to be launched. A strategy for monitoring calls from this program as well as other relevant programs was formulated. As a result of the work in this project, it has also been possible to formulate proposals for two specific PhD-student projects within the Preem-Chalmers cooperation. These proposals take the outcome of this project into account and include opportunities to further develop the collaboration between industrial energy systems and process control at Chalmers.
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| 18. |
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| 19. |
- Franck, Per-Åke, 1953, et al.
(författare)
-
Analys av vissa konsekvenser av långsiktiga avtal som styrmedel att effektivisera energianvändningen i industrin
- 1999
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Föreliggande rapport utgör en del av ett första steg i att ta fram förslag till långsiktiga avtal mellan stat och näringsliv inom området effektivare energiutnyttjande. Syftet med detta första steg är att utröna om det är möjligt och rimligt att utnyttja långsiktiga avtal i Sverige.I denna rapport analyseras konsekvenserna av att med långsiktiga avtal stimulera genomförandet av åtgärder som inte skulle genomförts utan intervention från staten. Analysen genomförs med utgångspunkt från tre fallstudier där åtgärder identifierats genom energikartläggningar.I ett första steg, applicerat på de tre fallstudierna, analyseras hur skatter fungerar som styrmedel och incitament att genomföra besparingsåtgärder. I denna del inkluderas hur emissionerna kan kvantifieras.I ett andra steg, utgående från fallstudiernas karakteristik avseende investeringar och besparingar, analyseras i detalj konsekvenserna av långsiktiga avtal. Dessa avtal innebär att industrin får utnyttja en del av koldioxidskatten för investeringar i åtgärder som inte skulle genomförts utan intervention från staten.
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| 20. |
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| 21. |
- Franck, Per-Åke, 1953, et al.
(författare)
-
Design of a vertical earth heat pump system. Results from system simulations.
- 1983
-
Ingår i: International conference on "Subsurface heat storage - in theory and practice" Stockholm June 6-8. ; 1983:Appendix, Part I, s. 168-175
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In the paper technical and economical aspects of introducing a vertical pipe heat storage with natural convection heat collector and heat pump in an existing building are discussed. The technical influence of the design parameters is studied with a big computer program which is briefly presented. The general influence of the design parameters is presented with special interest in the occurrence of freezing in the vicinity of the storage pipes. Some examples are given which show that an economical optimum storage/collector combination can be found. In this optimum storage freezing will occur. The reduction of total annual cost can be considerable compared to a non-freezing storage.
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| 22. |
- Franck, Per-Åke, 1953, et al.
(författare)
-
Ground-Coupled heat pumps with low-temperature heat storage: Some Swedish experiences
- 1985
-
Ingår i: ASHRAE Technical Data Bulletin - Advances in Nonazeotropic mixture refrigerants for heat pumps. ; 1985:1, s. 1285-1296
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A large research program in the field of solar-coupled heat pumps with seasonal storage in the ground, using vertical pipes to a depth of 10-40 m, has been going on for several years in Sweden. In this paper, some main results from two experimental plants are presented. As well, results from a technical-economical optimization study are discussed. In these calculations comparisons are made among systems using ambient-air natural convection heat exchangers, lowtemperature solar collectors, and II conventi ona 111 amb i ent-a i r heat pumps wi thout storage.One of the experimental plants heats a school and consists of low-temperature solar collectors on the roof, four diesel-driven heat pumps, and a storage system with vertical pipes in clay, depth 35 m. Seasonal performance factors (SPF's) are 3.6 (heat pumps) and 1.7 (total system). The other plant is an experimental one for a single-family house with an electrically driven heat pump, natural convection heat exchangers on the roof, and a storage system in clay, depth 10 m. Annual SPF's are 3.0 (heat pump) and 2.5 (including all auxiliary electricity consumption). Systems evaluation calculations indicate optimal sizes of the three main components, although the optimas are flat. The differences in economy between systems with solar collectors and with natural convection heat exchangers are small. However, systems with solar or ambientair heat collectors and storage systems cannot today compete economically with ambient-air heat pumps without storage systems, at least if Swedish conditions are assumed.
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| 23. |
- Franck, Per-Åke, 1953, et al.
(författare)
-
Heat Pump evaporators - A-state-of-the-Art Report
- 1989
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This volume contains the final report of lEA Advanced HeatPumps, Annex VII: "New Development of The Evaporator Partof Heat Pump Systems". The objectives of this Annex havebeen: To collect and evaluate existing theoretical and experimental information for the evaporator part of heat pump systems.Types of evaporators included have been equipment for bothliquid and gaseous heat sources used in direct as well asindirect systems.The work has been divided between the Operating Agent(Sweden) and the National Teams of Canada, Denmark,Finland, Norway, and Sweden.The major part of the work has been to collect informationon various aspects of the evaporator part, both from theliterature and from the National Teams. The result of thework is this report which contains the following chapters:1. INTRODUCTION2. HEAT PUMP EVAPORATOR TYPES3. HEAT TRANSFER AND PRESSURE DROP ON HEAT SOURCE SIDE OFHEAT PUMP EVAPORATORS4. HEAT TRANSFER AND PRESSURE DROP ON REFRIGERANT SIDE OFHEAT PUMP EVAPORATORS5. OPTIMIZATION OF HEAT PUMP EVAPORATORS6. RESEARCH AND DEVELOPMENT TRENDS IN THE PARTICIPATINGCOUNTRIES
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| 24. |
- Franck, Per-Åke, 1953, et al.
(författare)
-
Möjligheter att utnyttja värmepumpning i massa- och pappersindustrin - En kartläggning baserad på pinchanalys
- 1998
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I denna rapport kartläggs möjligheterna att i massa- och pappersindustrin utnyttjavärmepumpar genom att analysera referensbruk som representerar moderna energieffektivabruk. Detaljerade processdata finns definierade för delprocesserna, och dessa kombineras för att representera hela bruk. De brukstyper som analyserats är:• Integrerat kartongbruk med CTMP-fabrik.• Integrerat pappersbruk (normalt och hart slutet).• Avsalubruk (normalt och hart slutet).I de integrerade kartong- och pappersbruken räcker inte ångan som produceras i sodapannan for att tacka värmebehovet. I dessa fall måste kompletterande förbränning med t ex bark ske. En reduktion av processens värmebehov medför därför att förbränningen med det kompletterande bränslet kan reduceras. Förutsättningar för värmepumpning finns därför i dessa fall.I avsalubruken finns däremot ånga i överskott från sodapanna. Någon kompletterande förbränning behövs då inte. En värmebesparing i processen har då inget yärde och därmed finns inte heller några förutsättningar for värmepumpning internt i bruket.I de integrerade kartong- och pappersbruken finns mojligheter att utnyttja värmeöverskottkring 100°C och med en värmepump tillverka lågtrycksånga. Deuppskattade återbetalningstiderna, med hansyn tagen till förlorad mottryckskraftvid dagens energipriser, ar som lägst mellan 3 och 5 år. Beträffande investeringskostnaderråder det dock stora osäkerheter kring storleken på följdkostnaderna (dvs förändrade värmeväxlingar i sekundärsystemen i processen). I alla referensbruken finns ett stort värmeöverskott vid cirka 60°C beroende på främst värmen från indunstningens ytkondensorer och sodapannans rökgasskrubber. Detta värmeöverskott kan värmepumpas till ett fjärrvärmenät. och ger vid en årlig drifttid på 4000 timmar en produktionskostnad till bruksgränsen mellan 100 kr/MWh och 150 kr/MWh.Värmepumpar i modifierade enhetsoperationer ar också av intresse. Till exempel ger värmepumpning med en högtrycksfläkt i indunstningen ungefär samma totala årliga kostnader som med traditionell indunstning. Driftkostnaden ar dock lägre men kapitalkostnaden högre.
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| 25. |
- Franck, Per-Åke, 1953, et al.
(författare)
-
Optimization of a combined heat pump/storage system with solar or convective heat collectors
- 1985
-
Ingår i: Enerstock 85, Toronto Canada, September 22-26. ; 1985:D13, s. 448-455
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A large computer program simulating space heating systems in large multifamily houses or small district heating systems is presented. The system consists of a heat collector, either an ambient-air natural convective collector or a solar collector, a heat storage with vertical pipes in the ground, and an electrically driven heat pump. The most important technical and economical design parameters are the size of the collector, the storage, the heat pump, and the system control. The influence of these parameters on the annual COP and the heat supply ratio has been simulated and is discussed. This influence is presented in a generalized way. With the aid of the technical results an economic optimization is made of the system. The optimum is flat but sensitive to the combination of the system parts. A sensitivity analysis on the optimum is made to show the influence of investment and energy costs. Finally the system is compared with a heat pump without storage which is found to be somewhat more economically advantageous.
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| 26. |
- Franck, Per-Åke, 1953, et al.
(författare)
-
Process integration application in the pulp and paper industry
- 1999
-
Ingår i: International Conference on Process Integration, Copenhagen, Denmark, 7-10 March 1999. ; 1, s. 52-
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The pulp- and paper industry is characterised by a good energy utilisation. However, the potential for further reduction of the energy demand in this type of industry is still very high especially considering the ongoing and planned process changes. In traditional process integration studies, where process equipment is accepted, the found potential for steam reduction is normally 5 to 10%. Using process integration in the strategic process planning, and allowing for process modifications, much larger savings are possible, up to 50%. This reduction of the steam demand is obtained with a total integration of the evaporator and the bleaching plants but results also in a loss of co-generation power due to both the reduced steam load and an increased use of medium pressure steam. The large amount of free excess heat from the process that must be cooled away, can be utilised in a district heating net.
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| 27. |
- Franck, Per-Åke, 1953, et al.
(författare)
-
Process integration of various types of heat pumps
- 1990
-
Ingår i: Föredrag vid BHRA International Conference on Applications and Efficiency of Heat Pump Systems in Environmentally Sensitive Times, Munchen, Västtyskland. 1-3 Oktober 1990.
-
Konferensbidrag (refereegranskat)
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| 28. |
- Franck, Per-Åke, 1953, et al.
(författare)
-
Systemtänkande i massa- och pappersindustrins energiplanering
- 2008
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Kraven på kunskap kring energisystem inom massa- och pappersindustrin kommer troligen att öka kraftigt under den närmsta framtiden beroende på främst ökande energipriser, nya styrmedel för klimatet och ökat intresse för bioraffinaderier av olika slag. Från allmänna diskussioner med skogsindustriella programmets styrgrupp kan man anta att de allra flesta i styrgruppen har erfarenheter av hur systeminriktade frågor och designlösningar i många fall kommer i kläm i en beslutsprocess. Syftet med projektet är att identifiera dessa erfarenheter och problem med system-inriktade energilösningar i olika beslutssituationer. Arbetet har genomförts i form av telefonintervjuer med medlemmarna skogsindustriella programmets styrgrupp. Det är författarnas uppfattning att resultatet speglar individernas ärliga uppfattning i dessa frågor. Systemaspekter inom massa- och pappersindustrins energihantering är ett brett och inte väldefinierat område. Grovt räknat kan de indelas i tre nivåer, aspekter på brukens energiansvarignivå, på bruksnivå och på koncernnivå. Den här genomförda studien har inriktats främst mot den första nivån. De övriga nivåerna är minst lika viktiga för branschen i framtiden men analys av dem kräver ett annat angreppssätt. Åsikterna i intervjuerna hur väl systemtänkandet fungerar på bruken varierar mellan omdömena ”bra” och ”dåligt”. De som anser att systemtänkandet inte är tillfredställande framför att fixeringen på utrustningen är alldeles för stor och att man inte gör några djupa analyser med ett strukturerat helhetstänkande. De främsta orsakerna är att energipriserna historiskt inte har varit tillräckligt höga för att sätta energifrågorna i fokus och att tiden inte räcker till för en helhetssyn beroende på att andra saker kräver uppmärksamhet. Många framhåller dock att det under senare år skett en förändring i denna fråga och att det nu blivit betydligt bättre än vad det historiskt har varit och att det är de ekonomiska drivkrafterna som är avgörande. För att möjliggöra ett bättre systemtänkande nämns flera lösningar och möjligheter som har eller skulle kunna genomföras och förbättras: - Tillsättandet av en energisamordnare både på bruks- och koncernnivå som speciellt ska ägna sig åt energifrågorna. - Systemtänkandet måste förankras i den högsta ledningen. - Organisationen av investeringsprojekt måste ske på ett sätt som säkerhetsställer att systemaspekterna beaktas på ett korrekt sätt. - Användningen av bra verktyg för analyser ökar förståelsen för hur olika åtgärder och lösningar påverkar andra delar av bruket. - Samordna energiinvesteringar med förändringar i processen. - Uppföljning av genomförda investeringar för att behålla fokus på energifrågan och lära för framtiden. - Sprid goda exempel, till exempel de åtgärder som framkommit i PFE.
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| 29. |
- Franck, Per-Åke, 1953, et al.
(författare)
-
Technical and economical design of a combined heat pump/low temperature storage system. Results from system simulations.
- 1984
-
Ingår i: 2nd International Symposium on "The large scale applications of heat pumps", York, England: 25-27 September. ; 1984:C3, s. 95-105
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A computer program simulating a whole heating system for space heating in large multifamily houses or small district heating systems is presented. The system consists of an ambient-air natural convective heat collector, a heat store with vertical pipes in the ground, and an electrically driven heat pump.The most important design parameters from both a technical and an economical point of view are the sizes of the storage, the ambient-air heat collector, and the heat pump. The influence of these parameters on the technical result is discussed. With the aid of computer simulations it is shown how this influence can be presented in a generalized way. From this presentation a method to optimise this kind of system is outlined. Using typical costs for Sweden the total annual cost for some designs is calculated and a cost comparison is made with an oil fired burner.In the optimisation calculations optimum values for the main parts were determined. For the heat collector and the storage size flat optimums were found. The heat pump size shall in most cases be as large as is practically possible, when such aspects as freezing of the soil have been taken into account. Compared to an already existing oil fired burner and to a heat pump without storage this system was found to be more expensive. Decreasing investment cost and increasing energy costs in the future can however make the system economically favourable.
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| 30. |
- Franck, Per-Åke, 1953, et al.
(författare)
-
Värmepump med vertikalt jordvärmesystem och vindkonvektor
- 1981
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Utbyprojektet innebar att en enfamiljs villafastighet på Anders Mattssonsgatan 15, Utbynäs, se bilaga 1, skall varmas med eldriven värmepump. Huset, som ar byggt omkring 1910, utgör undertecknad Rosenblads med familj bostad sedan 1960. Det har tidigare eldats med olja till en kvantitet av val 4000 liter per normalår vid den relativt sett laga (= kyliga) värmestandard, som dagens oljepriser påtvingar en villaägare.Värmepumpen avser att ta upp den huvudsakliga delen av erforderligt lågtemperaturvärme från marken via ett system av vertikalt anordnade rör ned till ett djup av ca 10 m. Da värme sommartid icke kan hinna tränga ned till sådana djup, måste jordsystemet genom särskilda åtgärder tillföras värme under den varmare delen av året.Ett vertikalt system kräver avsevärt mindre markareal an ett horisontellt samtidigt som det genom årstidslagringen av energi bor finnas förhoppning om en bättre årsvärmefaktor.Det vertikala rörarrangemanget torde på grund av kravet på återladdning kräva en något mera komplicerad utformning an vid horisontella rör, där återladdningen sker automatiskt. Det vertikala systemet torde bl a därför ha sitt största intresse vid något större objekt i en tätare bebyggelse än där ytjordvärmesystem idag ar konventionell teknik.Projektets målsättning har varit och ar att som det första systemet av detta slag i Sverige, sannolikt också i världen, uppnå praktiska driftserfarenheter som underlag for att bedöma mojligheter till realisering och ekonomi. I projektet har också ingått val av lampliga komponenter och att utforma förslag till sådana, när marknaden icke haft lämpliga att erbjuda.
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| 31. |
- Franck, Per-Åke, 1953, et al.
(författare)
-
Värmepumpar i industriella processer
- 1991
-
Ingår i: Föredrag vid 5:E Nordiske Varmepumpdage, Lyngby, Danmark, 29-31 maj 1991.
-
Konferensbidrag (refereegranskat)
|
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| 32. |
- Johansson, Daniella, 1983, et al.
(författare)
-
A process integration analysis of H2 production from gasification of biomass in the oil refining industry
- 2010
-
Ingår i: 7th European Congress of Chemical Engineering 7, 19th International Congress of Chemical and Process Engineering CHISA 2010, conference proceedings.
-
Konferensbidrag (refereegranskat)abstract
- The refining industry faces a future with increasing hydrogen demand, a change in fuel mixture that increases process energy demand and at the same time a future with harder regulations on CO2 emissions. In this paper the CO2 effect of integrating different biomass gasification concepts to meet an increasing demand of hydrogen in an oil refinery are examined and presented in comparison with a conventional steam reformer. The result shows that if biomass is considered as an unlimited resource (i.e. CO2 neutral), biomass gasification concepts have a potential to reduce CO2 emissions. However, if biomass is considered as a limited resource, which is a likely future scenario, all studied concepts show an increase of CO2 emissions.
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| 33. |
- Johansson, Daniella, 1983, et al.
(författare)
-
CO2 capture at five industries at five industries in the Skagerrak area - Technical background report to: Carbon Capture and Storage in the Skagerrak/Kattegat region, Final report
- 2011
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- CO2 capture is an alternative to decrease CO2 emissions from industries. A large part of the cost for carbon capture is related to the heat supply to the capture plant. In this study four alternatives to supply the heat demand in the capture plant at five industries in the Skagerrak area are evaluated. These industries are Preem Göteborg, Preem Lysekil, Esso Slagentangen, Borealis Stenungsund and Yara Porsgrunn. The heat supply alternatives are; Natural Gas Combined Cycle, Natural Gas Boiler, Biomass Boiler and Excess heat from the process alone or in combination with a Heat Pump.The lowest specific capture costs are found when excess heat is utilized. In those plants where the available amount of excess heat is not large enough to cover the whole heat demand in the capture plant, via direct heat exchange, the lowest specific capture cost is found when a heat pump also is used. Specific capture costs of 45 to 60 €/ton can be reached in such systems. The specific avoidance costs are the same for these systems since no fossil fuel is used. Higher specific costs are found if the heat from the heat pump is not large enough to cover the heat demand in the capture plant and supplementary heat via a heat supply plant (e.g. a boiler) is needed.
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| 34. |
- Johansson, Daniella, 1983, et al.
(författare)
-
CO2 capture in oil refineries-an evaluation of different heat integration possibilities for heat supply to the post-combustion process
- 2011
-
Ingår i: Linköping Electronic Conference Proceedings, No.57. World Renweable Energy Congress 2011, May 8-13, Linköping, Sweden.
-
Konferensbidrag (refereegranskat)abstract
- This paper estimates the costs of CO2 post-combustion capture for two refineries by comparing different alternatives for supplying the heat needed for the regeneration of the absorbent. The cost of capture ranges from 30 to 472 €/ tCO2 avoided, depending on technology choice for heat supply and energy penalty for the CO2 separation. In this study, it is concluded that process integration leads to a reduction in avoidance costs. However, the avoidance cost depends greatly on which system perspective is considered, i.e. whether CO2 emission changes outside the refinery are included or not.
|
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| 35. |
- Johansson, Daniella, 1983, et al.
(författare)
-
CO2 capture in oil refineries: Assessment of the capture avoidance costs associated with different heat supply options in a future energy market
- 2013
-
Ingår i: Energy Conversion and Management. - : Elsevier BV. - 0196-8904. ; 66, s. 127-142
-
Tidskriftsartikel (refereegranskat)abstract
- The application of post-combustion CO2 capture represents an alternative strategy to reduce significantly CO2 emissions from the oil refining industry. Previous studies have shown that the highest costs are related to the provision and use of energy and that these costs could be reduced by utilising excess heat. In the present study, we investigated whether this principle could be applied to the oil refining industry. Four heat supply alternatives were evaluated: Natural Gas Combined Cycle; Natural Gas Boiler; Biomass Boiler; and Excess Heat. These alternatives were evaluated using future energy market scenarios and two levels of heat demand. The Natural Gas Combined Cycle alternative generated high levels of electricity (with CO2 capture), thereby producing the greatest reduction in global CO2 emissions. However, the avoided CO2 emissions from onsite the refinery were highest when excess heat or a biomass boiler was used. In the present study, the capture avoidance cost ranged from 40 to 263 (sic)/tCO(2) avoided (excluding transportation and storage costs), depending on the heat supply alternative used and the heat demand. Moreover, with a high cost for CO2, CO2 capture using excess heat could be a cost-effective alternative to reduce CO2 emissions for oil refineries.
|
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| 36. |
- Johansson, Daniella, 1983, et al.
(författare)
-
Comparative study of Fischer-Tropsch production and post-combustion CO2 capture at an oil refinery: Economic evaluation and GHG (greenhouse gas emissions) balances
- 2013
-
Ingår i: Energy. - : Elsevier BV. - 0360-5442 .- 1873-6785. ; 59, s. 387-401
-
Tidskriftsartikel (refereegranskat)abstract
- The impact on CO2 emissions of integrating new technologies (a biomass-to-Fischer-Tropsch fuel plant and a post-combustion CO2 capture plant) with a complex refinery has previously been investigated separately by the authors. In the present study these designs are integrated with a refinery and evaluated from the point-of-view of economics and GHG (greenhouse gas emissions) emissions and are compared to a reference refinery. Stand-alone Fischer-Tropsch fuel production is included for comparison. To account for uncertainties in the future energy market, the assessment has been conducted for different future energy market conditions. For the post-combustion CO2 capture process to be profitable, the present study stresses the importance of a high charge for CO2 emission. A policy support for biofuels is essential for the biomass-to-Fischer-Tropsch fuel production to be profitable. The level of the support, however, differs depending on scenario. In general, a high charge for CO2 economically favours Fischer-Tropsch fuel production, while a low charge for CO2 economically favours Fischer-Tropsch fuel production. Integrated Fischer-Tropsch fuel production is most profitable in scenarios with a low wood fuel price. The stand-alone alternative shows no profitability in any of the studied scenarios. Moreover, the high investment costs make all the studied cases sensitive to variations in capital costs. (C) 2013 Elsevier Ltd. All rights reserved.
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| 37. |
- Johansson, Daniella, 1983, et al.
(författare)
-
Hydrogen production from biomass gasification in the oil refining industry - A system analysis
- 2012
-
Ingår i: Energy. - : Elsevier BV. - 0360-5442 .- 1873-6785. ; 2012:38, s. 212-227
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, the global CO2 effect of integrating different biomass gasification concepts to meet anincreasing demand of hydrogen in an oil refinery is examined and presented in comparison with a conventional steam reformer. The studied refinery is a hydro skimming refinery with a future hydrogen deficit of 16,000 Nm3/h. Three gasification concepts are considered: Entrained Flow (EF), Circulated Fluidised Bed (CFB) and Double Bed (DB). The system analysis is made with respect to global CO2 emissions and primary energy use. The results show that if biomass is considered as an unlimited resource (i.e. sufficient biomass is considered to be available to substitute for all fossil fuels in society), biomass gasification concepts have a potential to reduce CO2 emissions. The EF case shows the largest reduction potential. However, if biomass is considered as a limited resource (i.e. increased use of biomass at the refinery will lead to increased use of fossil fuel elsewhere in society), all concepts show an increase of CO2 emissions. Here, the CFB gasifier shows lowest increase of CO2 emission. The CO2 effect of the different alternatives shows sensitivity to assumptions regarding alternative biomass user.
|
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| 38. |
- Johansson, Daniella, 1983, et al.
(författare)
-
Integration of Fischer-Tropsch Diesel Production with a Complex Oil Refinery
- 2012
-
Ingår i: In Proceedings of SDEWES – the 7th Conference on Sustainable Development of Energy, Water and Environment Systems, Ohrid, Republic of Macedonia, 1-7 July 2012. ; , s. paper 082-
-
Konferensbidrag (refereegranskat)abstract
- The oil refining industry is facing harder regulations on renewable content in its products. One way to meet this is to produce diesel and gasoline from gasification of biomass via a Fischer-Tropsch synthesis. In this paper, integrating a biomass-to-FT syncrude process with a refinery is compared to a stand-alone biomass-to-FT syncrude process, in terms of the consequences for CO2 emissions and energy balances. The upgrading of the FT syncrude is in both cases accomplished at the refinery, in the existing units or in new units. The studied system includes a circulating fluidized-bed biomass gasifier with a biomass input of 500 MW (50% moisture content) and a complex refinery with a crude oil capacity of 11.4 Mt/y. The integrated FT-syncrude production shows, regardless of assumptions of marginal electricity generation, the largest CO2 emission reduction. Moreover, if the almost clean CO2 stream from the biomass-to-FT-syncrude production is captured, the reduction potential can be significantly increased.
|
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| 39. |
- Johansson, Daniella, 1983, et al.
(författare)
-
Integration of Fischer-Tropsch fuel production with a complex oil refinery
- 2014
-
Ingår i: International Journal of Environment and Sustainable Development. - 1474-6778 .- 1478-7466. ; 13:1, s. 50-73
-
Tidskriftsartikel (refereegranskat)abstract
- The oil refining industry is facing harder policies on renewable content in its products. One way to meet this is to produce diesel and gasoline from gasification of biomass via a Fischer-Tropsch (FT) synthesis. In this paper, heat integrating a biomass-to-FT syncrude process with a refinery is compared to a stand-alone biomass-to-FT syncrude process, in terms of the consequences for GHG emissions and energy balances. The upgrading of the FT syncrude is in both cases accomplished at the refinery, in the existing units or in new units. The studied system includes a circulating fluidised-bed biomass gasifier with a biomass input of 500 MW (50% moisture content) and a complex refinery with a crude oil capacity of 11.4 Mt/y. The integrated FT syncrude production shows the greatest potential for reductions in GHG emissions. Still, the GHG emission mitigation potential of using biomass for FT fuel production is smaller than co-firing biomass with coal in coal power plants.
|
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| 40. |
- Larsson, Bertil, et al.
(författare)
-
Värmeinfångning med vindkonvektorer för jordvärmeanläggningar - Studier på 1940 - 60-tals flerbostadshus, Rapport nr 16
- 1985
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Vid Ruddalens isbaneanläggning installerades 1981 en värmepump. Man utnyttjar här det faktum att man inom ett relativt begränsat område har både kyl- och värmebehov.Sommartid fungerar skridsko- och bandybanor sam värmeupptagande ytor, varvid värme från sol och luft överförs till värmepumpen via den cirkulerande CaC12-1ösningen. Vintertid används värmepumpen tillsammans med den ursprungliga kylanläggningen för nödvändig kylning av isbanorna. Det på så vis erhållna värmet från värmepumpen används for att varma varmvatten till närliggande bostadsområden. Distributionen sker via en intilliggande panncentral, där även temperaturen på det utgående varmvattnet kan höjas vid behov. Antalet abonnenter är ca 3500 lägenheter.Mätningar på värmepumpsanläggningen har genomforts under tiden januari 1983 - september 1984. Syftet med dessa har varit att kartlägga själva värmepumpens arbetssätt under olika driftförhållanden. Faktorer som påverkar värmekällan (solstrålning, utetemperatur, vindstyrkor, etc) eller värmesänkan (reglerstrategier i panncentralen, utetemperatur, etc) har inte studerats. Projektet har genomforts sam ett ”lågbudgetprojekt" for uppföljning av värmepumpen. Den totala projektkostnaden har varit ca 100 000 kr inklusive matutrustning.
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| 41. |
|
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| 42. |
- Strömberg, Jan, 1962, et al.
(författare)
-
Consequences of recent gas turbine developments for industrial CHP applications
- 1993
-
Ingår i: Heat Recovery Systems & CHP. ; 13:3, s. 219-231
-
Tidskriftsartikel (refereegranskat)abstract
- Developments in gas turbine (GT) technology have been considerable during the last few years. In this paper, consequences regarding the technical performance for industrial combined heat and power applications are discussed and the most important design parameters are identified. Some GT types, which represent different stages of the developmental trend, are analysed in the simple and the combined cycle. Both the industrial and the aero-derivative GT classes are included. Conclusions are: (i) Generally, the developments have broadened the span of achievable power-to-heat ratios (α-values). Values between 0 and 1.5 are obtainable for different GT-based schemes with acceptable total efficiencies. (ii) The total efficiencies achievable depend strongly, and differently for different GT types, on the nature of the heat demands in the industrial process. (iii) When opportunities do not exist to cool the exhaust gases in an economizer, i.e. when the stack temperature is directly given by process heat demands, the total efficiency is independent of the GT class. For both classes, however, the development has led to higher total efficiencies when the process temperature demands are high. (iv) When opportunities exist to cool the exhaust gases in an economizer (which is often the case for the simple cycle and always for the combined cycle), the industrial GT developments have given improved ability to reach a high total efficiency. The new aero-derivative types, on the contrary, are worse than the conventional ones in this respect. This can also lead to worse performance in combined cycles for the new aero-derivative types. (v) When supplementary firing is applied, however, the total efficiency is high and similar for all various units and conditions. The ‘new aero-derivative’ units have, in that case, superior α-values—especially in the combined cycle.
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| 43. |
- Strömberg, Jan, 1962, et al.
(författare)
-
Gas turbines in industrial CHP applications - Assesment of economics
- 1994
-
Ingår i: Heat Recovery Systems & CHP. - : Elsevier BV. - 0890-4332. ; 14:2, s. 129-141, 1994
-
Tidskriftsartikel (refereegranskat)abstract
- abstract-Gas turbine (GT) units (of both the industrial and the aero-derivative type) at different developmental stages are economically assessed in both simple and combined cycle. The CHP plant supplies heat (at varying levels) to an industrial plant which currently uses some existing heating device to meet this heat requirement. The following is concluded regarding the payback periods (PBPs) obtained: (i) The CHP plant efficiencies have minor impact at high electricity-to-fuel price ratios (y values). (ii) At lower T values the efficiencies, and hence the GT type selection and nature of the heat requirement, become important. New and future GTs will then offer short PBPs, compared to conventional industrial GTs. (iii) A high electrical efficiency does not regularly imply short PBPs-sometimes the situation is actually the opposite. (iv) With an advanced GT or a combined cycle the electricity production for a given heat requirement can be substantially increased, compared to that for a less advanced GT, without any substantial increase in PBP (provided that these three systems are all designed for high total efficiencies and have similar investment costs). (v) A PBP rank ordering of various CHP options is not affected by the magnitude of the ~ value. With a life-cycle cost method, CHP plants with high power-to-heat ratios (such as the most advanced simple cycle GT and combined cycles) will be put in a favourable light-particularly if the profitability requirement is low. The rank ordering of these plants also benefits from a high y value.
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| 44. |
- Wallin, Erik, 1959, et al.
(författare)
-
Heat pumps in industrial processes - an optimization methodology
- 1990
-
Ingår i: Heat Recovery Systems & CHP. ; 10:4, s. 437-446
-
Tidskriftsartikel (refereegranskat)abstract
- The optimal integration of heat pumps in industrial processes has not yet been fully understood. In this paper an optimization methodology and a method which uses the composite curves as a guideline to the correct choice of heat pump type are outlined. The selection is done by matching the shape of the composite curves against the specific characteristics of several heat pump types. Furthermore, a methodology for the optimization of the most important parameters in a heat pump system is presented. In the optimization methodology the annual cost is minimized by varying heat source and heat sink temperatures, the heat pump size and the stream or streams to be utilized as heat source and heat sink.To reveal the potential for electrically driven compression heat pumps two different examples were studied with the methodology. The first example had close composite curves and was thought to be a poor heat pump candidate. The second one had open composite curves and was thought to be a promising example. The results showed that for both examples, heat pump installations were advantageous under good economic conditions for the heat pump, i.e. low electricity price, high fuel price and low investment costs. Also reasonable payback periods were achieved. With more unfavourable conditions the payback period increased, and in extreme cases a heat pump was no longer a better alternative than pure heat exchange. This decline in potential for heat pumping was much less in the example with open composite curves than in the example with closed ones. However, the conclusion to be drawn is that there exists today a potential for heat pumps in industrial processes.
|
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| 45. |
- Wallin, Erik, 1959, et al.
(författare)
-
Introduction of heat pumps in industrial processes
- 1988
-
Ingår i: Föredrag vid "Second Workshop on Research Activities on Advanced Heat Pumps" in Graz, 26-29 september 1988.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- By using pinch technology, which is a methodology of analyzing industrial processes in a thermodynamically correct way, criteria have been established how to choose the correct heat pump type depending on the characteristics of the specific process stream system. Furthermore, an economic optimization of the compression heat pump type has been performed in two different process systems under various economic conditions. From these two examples the conclusion to be drawn is that the potential for heat pumping in industry looks promising.
|
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| 46. |
|
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| 47. |
- Wimby, Martin, 1960, et al.
(författare)
-
A large absorption heat pump
- 1987
-
Ingår i: 3rd International Symposium on the Large Scale Applications of Heat Pumps, Oxford, England: 25-27 March 1987. ; :Paper A3, s. 21-24
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In November 1984 the first large absorption heat pump (AHP) in Sweden was installed. The AHP delivers 7 MV heat to a district heating system, using excess steam as drive energy and cooling water as heat source. The steam and the cooling water originate from a near by chemical plant aswaste energy. The heat pump is manufactured by SANYO. It is one of the largest AHP (type I) in the world so far.The generator is heated with 10 bar steam and in the evaporator, water is cooled from 60°C to 30°C. The heat pump raises the temperature of the district heating water from 60°C to 80°C. The working pair used is Lithium bromide-water. A single control loop reduces the steam flow when the temperature of the district heating waterexceeds 83°C.In this paper the energy balances and internal behavior of the heat pump are presented. The energy balances were continuously determined from temperature and flow recordings every other minute in the external streams of the AHP. The internal behavior - such as heat transfer - have been studied by means of surface temperature sensors. The COP was found to vary between 1.3 and 1.8 with a mean value of 1.6. Since startup the availability has been 100 %. The AHP is very flexible with load variations between 0 % and 100 % without complications. Corrosion has been avoided by means of inhibitors and a purge pump system.
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| 48. |
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| 49. |
|
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| 50. |
- Åsblad, Anders, 1956, et al.
(författare)
-
Pinch analysis at Preem LYR II - Modifications
- 2014
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This energy inventory and pinch analysis of the Preem, Lysekil refinery is a part of the Preem – Chalmers research cooperation and has been carried out by CIT Industriell Energi AB. This report is Part II of the report “Pinch analysis at Preem LYR”. The aim with the first part was to supply the researchers at Chalmers with energy data from the refinery in a form that is suitable for different types of pinch analysis. Furthermore, the aim was to make an analysis to establish the possible energy saving potentials in the refinery at various levels of process integration constraints.In this report, “Pinch analysis at Preem LYR, Part II”, we have applied pinch analysis methods such as the “Matrix Method” and “Advance Composite Curves” to find concrete improvements in the heat recovery network.The process units of the refinery have a net heat demand of 409 MW (for the operation case studied) which is supplied by firing fuel gas. Steam is generated in the process by cooling process streams. Most of the generated steam is used in the process units (167 MW) and the remainder (17 MW) is used for other purposes.The energy saving potential, that is the theoretical savings that are achievable, depends on the constraints put on the heat exchanging between process streams in the refinery. Three levels have been analysed:A: There are no restrictions on the process streams that may be heat exchanged in the refinery. In this case the minimum heat demand is 199 MW giving a theoretical savings potential of 210 MW.B: All streams within each process unit can be exchanged with each other, but direct heat exchange between process units is not permitted. In this case the minimum heat demand of each process unit must be calculated. The total savings potential, 146 MW, is calculated by adding the savings potential for the separate units.C: Heat exchange between process units is allowed for those streams which are heat exchanged with utility today (e.g., steam, air, cooling water). However, it is not allowed to modify existing process to process heat exchangers. The scope of the analysis is limited to only consider the 5 largest process units. This group of units are using ~90 %, 363 MW, of the added external heat. It is possible to reduce the external heat demand with 57 MW to 306 MW.In this report, part II, we give results of possible modifications identified in two process areas, ICR 810 and MHC 240. These areas were selected for further analysis due to their large energy savings potentials. Another area with high potential was CDU+VDU. However, improvements in this area were made during the 2013 turnaround.To reach the savings potential calculated in Part I, a Maximum Energy Recovery (MER)-network must be constructed. This will however involve a large number of new and modified heat exchangers. It is unlikely that a MER design would be economical in a retrofit situation. Therefore, the trade-off between capital costs and energy savings in a retrofit situation must be evaluated. However, this analysis is not yet done.The modifications suggested in this study include different levels of increased heat integration.
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