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- Andersson, Eva Ingeborg Elisabeth, 1956, et al.
(författare)
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Pinch analysis at Preem LYR
- 2013
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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. 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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- Andersson, Eva Ingeborg Elisabeth, 1956, et al.
(författare)
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TSA II Stenungsund - Investigation of opportunities for implementation of proposed energy efficiency measures
- 2011
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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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- Andersson, Viktor, 1983, et al.
(författare)
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Efficient Utilization of Industrial Excess Heat for Post-combustion CO2 Capture: An Oil Refinery Sector Case Study
- 2014
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Ingår i: Energy Procedia. - : Elsevier BV. - 1876-6102. ; 63, s. 6548-6556
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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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- Andersson, Viktor, 1983, et al.
(författare)
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Industrial excess heat driven post-combustion CCS: The effect of stripper temperature level
- 2014
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Ingår i: International Journal of Greenhouse Gas Control. - : Elsevier BV. - 1750-5836. ; 21, s. 1-10
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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)
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Techno-economic analysis of excess heat driven post-combustion CCS at an oil refinery
- 2016
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Ingår i: International Journal of Greenhouse Gas Control. - : Elsevier BV. - 1750-5836. ; 45, s. 130-138
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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
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Ingår i: Energy Procedia. - : Elsevier BV. - 1876-6102. ; 37, s. 7205-7213
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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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| 10. |
- Berntsson, Thore, 1947, et al.
(författare)
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Learning from experiences with Industrial Heat Pumps
- 1997
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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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