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- Andersson, Eva Ingeborg Elisabeth, 1956, et al.
(författare)
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Energy Efficient upgrading of Biofuel Integrated with a Pulp Mill
- 2003
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Ingår i: Proceedings of ECOS 2003, Copenhagen, Denmark. - 1404-7098.
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Konferensbidrag (refereegranskat)abstract
- This paper presents and evaluates different energy-efficient options for integrating drying and pelletising of biofuel with a modem energy-efficient pulp mill process. When drying biofuel, a large amount of the heat input can often be recovered. One option for heat recovery is to cover low temperature heat demand in the pulping process. Alternatively available excess heat from the pulp mill can be used for drying. Both alternatives will contribute to a better energy efficiency for the combined pulp mill and biofuel upgrading facility. Pinch analysis tools can be used to estimate the excess heat potential at different temperature levels in the pulp mill. Three different technologies for pulp mill integrated biofuel drying were retained for the study, namely steam drying, flue gas drying and vacuum drying. The different technologies are evaluated on the basis of energy usage, global CO2 emissions and resulting pellets production cost, using stand-alone pellets production as a reference. The pulp mill assumed for the calculations is the Eco-Cyclic reference pulp mill. The results of the study indicate that the most attractive integrated drying technology option is the flue gas dryer, using flue gases from the black liquor boiler. With the available flue gas stream at the reference pulp mill, a potential pellets production of 70 000 tonnes/yr could be achieved at a cost of 24.6 €/tonne. The associated reduction in CO, emissions compared to stand-alone pellets production is 31-36 kg/MWhpellets.
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| 3. |
- Andersson, Eva Ingeborg Elisabeth, 1956, et al.
(författare)
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Pulp-mill integrated biorefineries: a framework for assessing net CO2 emission consequences
- 2004
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Ingår i: Proceedings, AIChE 2004 Fall Annual Meeting. Nov 7-12, 2004, Austin, Texas, USA. ; , s. p 203-208, s. 203-208
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- There is currently much interest in producing biofuel-based transportation fuels. However, since biofuel is a limited renewable resource, it is important to assess whether such fuels are both produced and used as efficiently as possible. Efficient production can be achieved in the future by integrated biorefinery operations at pulp mill sites, co-producing pulp and biofuel-based energy products. This paper compares production of transportation fuel with other biorefinery options for future pulp mills. The comparison is based on net CO2 emissions, i.e. accounting for off-site consequences associated with changes in the net flows of electricity, biofuel and biofuel-based transportation fuel entering or leaving the mill. The most important conclusion is that system variables (e.g. assumptions regarding the reference fuel and engine efficiency for future transportation systems) are of decisive importance for the net CO2 emissions associated with pulp mill biorefinery operations. This paper illustrates such aspects and underlines the importance of a system perspective in process engineering research.
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| 4. |
- Andersson, Eva Ingeborg Elisabeth, 1956, et al.
(författare)
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System analysis of hydrogen production from gasified black liquor
- 2004
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Ingår i: Proceedings of the 17th International Conference on Efficiency, Cost,Optimization, Simulation and Environmental Impact of Energy and Process Systems, ECOS 2004, Guanajuato, Mexico July 7-9, 2004 , Edited. by R. Rivero et al.. - 9684890273 ; , s. pp 1435-1445
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Konferensbidrag (refereegranskat)abstract
- Hydrogen produced from renewable biofuel is both clean and CO2 neutral. This paper evaluates energy and global CO2 emissions consequences of integration of hydrogen production from gasified black liquor in a chemical pulp mill. A model of hydrogen production from gasified black liquor was developed and integration possibilities with the pulp mills energy system were evaluated in order to maximize energy recovery. The potential hydrogen production is 59 000 tonnes per year if integrated with the KAM reference market pulp mill producing 630 000 Air dried tonnes (ADt) pulp/year. Changes of global CO2 emissions associated with modified mill electric power balance, biofuel import and end usage of the produced hydrogen are presented and compared with other uses of gasified black liquor such as electricity production and methanol production. Hydrogen production will result in the greatest reduction of global CO2 emissions and could reduce the Swedish CO2 emissions by 10 % if implemented in all chemical market pulp mills. The associated increases of biofuel and electric power consumption are 5 % and 1.7 %, respectively.
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| 5. |
- Andersson-Gunnerås, Sara, et al.
(författare)
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Asymmetric expression of a poplar ACC oxidase controls ethylene production during gravitational induction of tension wood
- 2003
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Ingår i: The Plant Journal. - : Blackwell Publishing. - 0960-7412 .- 1365-313X. ; 34:3, s. 339-349
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Tidskriftsartikel (refereegranskat)abstract
- Ethylene is produced in wood-forming tissues, and when applied exogenously, it has been shown to cause profound effects on the pattern and rate of wood development. However, the molecular regulation of ethylene biosynthesis during wood formation is poorly understood. We have characterised an abundant 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase gene (PttACO1) in the wood-forming tissues of Populus tremula (L.) × P. tremuloides (Michx). PttACO1 is primarily expressed in developing secondary xylem, and is specifically upregulated during secondary wall formation. Nevertheless, according to GC–MS analysis combined with tangential cryosectioning, the distribution of ACC was found to be fairly uniform across the cambial-region tissues. Gravitational stimulation, which causes tension wood to form on the upper side of the stem, resulted in a strong induction of PttACO1 expression and ACC oxidase activity in the tension wood-forming tissues. The ACC levels increased in parallel to the PttACO1 expression. However, the increase on the upper (tension wood) side was only minor, whereas large amounts of both ACC and its hydrolysable conjugates accumulated on the lower (opposite) side of the stem. This suggests that the relatively low level of ACC on the tension wood side is a result of its conversion to ethylene by the highly upregulated PttACO1, and the concurrent accumulation of ACC on the opposite side of the wood is because of the low PttACO1 levels. We conclude that PttACO1 and ACC oxidase activity, but not ACC availability, are important in the control of the asymmetric ethylene production within the poplar stem when tension wood is induced by gravitational stimulation.
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| 7. |
- Frisk, U., et al.
(författare)
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The Odin satellite - I. Radiometer design and test
- 2003
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Ingår i: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 402:3, s. L27-L34
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Tidskriftsartikel (refereegranskat)abstract
- The Sub-millimetre and Millimetre Radiometer (SMR) is the main instrument on the Swedish, Canadian, Finnish and French spacecraft Odin. It consists of a 1.1 metre diameter telescope with four tuneable heterodyne receivers covering the ranges 486-504 GHz and 541-581 GHz, and one fixed at 118.75 GHz together with backends that provide spectral resolution from 150 kHz to 1 MHz. This Letter describes the Odin radiometer, its operation and performance with the data processing and calibration described in Paper II.
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| 8. |
- Hillier, Ladeana W, et al.
(författare)
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Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution
- 2004
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Ingår i: Nature. - 0028-0836 .- 1476-4687. ; 432:7018, s. 695-716
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Tidskriftsartikel (refereegranskat)abstract
- We present here a draft genome sequence of the red jungle fowl, Gallus gallus. Because the chicken is a modern descendant of the dinosaurs and the first non-mammalian amniote to have its genome sequenced, the draft sequence of its genome--composed of approximately one billion base pairs of sequence and an estimated 20,000-23,000 genes--provides a new perspective on vertebrate genome evolution, while also improving the annotation of mammalian genomes. For example, the evolutionary distance between chicken and human provides high specificity in detecting functional elements, both non-coding and coding. Notably, many conserved non-coding sequences are far from genes and cannot be assigned to defined functional classes. In coding regions the evolutionary dynamics of protein domains and orthologous groups illustrate processes that distinguish the lineages leading to birds and mammals. The distinctive properties of avian microchromosomes, together with the inferred patterns of conserved synteny, provide additional insights into vertebrate chromosome architecture.
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