Scholarly article on topic 'CCS Feasibility Improvement in Industrial and Municipal Applications by Heat Utilisation'

CCS Feasibility Improvement in Industrial and Municipal Applications by Heat Utilisation Academic research paper on "Civil engineering"

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Abstract of research paper on Civil engineering, author of scientific article — Janne Kärki, Eemeli Tsupari, Antti Arasto

Abstract This paper describes implications of applying carbon capture and storage in combined heat and power (CHP) production and in steel industry through three case study approaches conducted in Finland. Utilisation of low temperature process heat from capture plant, air separation unit or CO2 compression in district heating system and/or industrial solutions offers significant potential to increase overall efficiency and feasibility of CCS processes. The effects of CCS on the local CHP systems were included within the studied system boundaries in order to evaluate the economics and emissions from investor's (local energy company) point of view. Effect of CCS on greenhouse gas (GHG) emissions and operation economics of the CCS cases are compared to the reference system with varying parameters of operation. Regarding the GHG emissions, besides the site emissions, the main effects on global GHG emissions are also taken into account by using system modeling and streamlined LCA. In the case studies the whole CCS chain, including CO2 capture, processing, transport and storage, was included. Carbon capture processes were modeled using Aspen Plus and Prosim process modeling software and the results were used in CCS plant economics toolkit (CC-Skynet™) to estimate CO2 emission reduction possibilities and carbon abatement costs. Studied case studies included three main applications which were studied in different operational situations. The properties of reference plants and CHP systems are based on the real operational CHP units and steel mill in Finland. The first presented application is retrofit of about 1000 MWfuel CHP plant with post combustion capture technology. Natural gas fired GTCC plant is part of relatively large district heating network including also other CHP units in the same network. The plant is situated on the coastal area of Southern Finland and it emits approximately 1.3 Mtn CO2/year. The second application is a greenfield about 500 MWfuel CHP plant situated on the coast of the Gulf of Bothnia and emitting approximately 1.5 Mtn CO2/year. The plant is based on a modern CFB-boiler which is equipped with oxy- fuel technology in the CCS case. The studied fuel-shares with and without CCS consisted of pure biomass, pure peat and biomass-peat co-firing. In the study it is assumed that the economic incentive for negative CO2 emission is included in EU ETS for Bio-CCS. The plant is connected to the existing district heating network where older CHP plant already exists. Another plant and limited district heat consumption in the area limits the benefits obtained from CCS heat recovery. The third application is an integrated steel mill situated on the coast of the Gulf of Bothnia and emitting approximately 4.0 Mtn CO2/year altogether. The mill is retrofitted for post combustion capture and implications of different capture amounts, different solvents and process integration levels are compared to the base case steel production with varying operational parameters. Process heat is utilized also as district heat but heat consumption in the district heat network is smaller than the amount of recoverable process heat in the mill. The results showed that significant improvements can be achieved by CHP in plants utilizing CCS, especially in the case of oxy-fuel. The feasibility of CCS is heavily dependent not only on the characteristics of the facility and the operational environment but also on the chosen system boundaries and assumptions. In combined heat and power plants, major improvements can be obtained with heat integration, especially, in the production of district heat. In the near future particularly large, new and flexible CHP plants, which can burn coal, biomass or peat, are seen as promising candidates for CCS in Finland.

Academic research paper on topic "CCS Feasibility Improvement in Industrial and Municipal Applications by Heat Utilisation"

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Energy Procedia 37 (2013) 2611 - 2621

GHGT-11

CCS feasibility improvement in industrial and municipal applications by heat utilisation

Janne Karkia*, Eemeli Tsuparia, Antti Arastob

aVTT Technical Research Centre of Finland, P.O. Box 1603 (Koivurannantie 1), Jyvaskyla FI-40101, Finland _b VTT Technical Research Centre of Finland, P.O. Box 1000 (Biologinkuja 5), Espoo FI-02044 VTT, Finland_

Abstract

This paper describes implications of applying carbon capture and storage in combined heat and power (CHP) production and in steel industry through three case study approaches conducted in Finland. Utilisation of low temperature process heat from capture plant, air separation unit or CO2 compression in district heating system and/or industrial solutions offers significant potential to increase overall efficiency and feasibility of CCS processes. The effects of CCS on the local CHP systems were included within the studied system boundaries in order to evaluate the economics and emissions from investor's (local energy company) point of view. Effect of CCS on greenhouse gas (GHG) emissions and operation economics of the CCS cases are compared to the reference system with varying parameters of operation. Regarding the GHG emissions, besides the site emissions, the main effects on global GHG emissions are also taken into account by using system modeling and streamlined LCA.

In the case studies the whole CCS chain, including CO2 capture, processing, transport and storage, was included. Carbon capture processes were modeled using Aspen Plus and Prosim process modeling software and the results were used in CCS plant economics toolkit (CC-Skynet™) to estimate CO2 emission reduction possibilities and carbon abatement costs. Studied case studies included three main applications which were studied in different operational situations. The properties of reference plants and CHP systems are based on the real operational CHP units and steel mill in Finland.

The first presented application is retrofit of about 1000 MWfuel CHP plant with post combustion capture technology. Natural gas fired GTCC plant is part of relatively large district heating network including also other CHP units in the same network. The plant is situated on the coastal area of Southern Finland and it emits approximately 1.3 Mtn CO2 /

The second application is a greenfield about 500 MWfuel CHP plant situated on the coast of the Gulf of Bothnia and emitting approximately 1.5 Mtn CO2 / year. The plant is based on a modern CFB-boiler which is equipped with oxy-fuel technology in the CCS case. The studied fuel-shares with and without CCS consisted of pure biomass, pure peat and biomass-peat co-firing. In the study it is assumed that the economic incentive for negative CO2 emission is included in EU ETS for Bio-CCS. The plant is connected to the existing district heating network where older CHP plant already exists. Another plant and limited district heat consumption in the area limits the benefits obtained from CCS heat recovery.

* Corresponding author. Tel.: +350 40 7510053; fax: +358 20 722 2720 E-mail address: janne.karki@vtt.fi

1876-6102 © 2013 The Authors. Published by Elsevier Ltd. Selection and/or peer-review under responsibility of GHGT doi:10.1016/j.egypro.2013.06.145

The third application is an integrated steel mill situated on the coast of the Gulf of Bothnia and emitting approximately 4.0 Mtn CO2 / year altogether. The mill is retrofitted for post combustion capture and implications of different capture amounts, different solvents and process integration levels are compared to the base case steel production with varying operational parameters. Process heat is utilized also as district heat but heat consumption in the district heat network is smaller than the amount of recoverable process heat in the mill.

The results showed that significant improvements can be achieved by CHP in plants utilizing CCS, especially in the case of oxy-fuel. The feasibility of CCS is heavily dependent not only on the characteristics of the facility and the operational environment but also on the chosen system boundaries and assumptions. In combined heat and power plants, major improvements can be obtained with heat integration, especially, in the production of district heat. In the near future particularly large, new and flexible CHP plants, which can burn coal, biomass or peat, are seen as promising candidates for CCS in Finland.

© 2013 The Authors. Published by Elsevier Ltd. Selection and/or peer-review under responsibility of GHGT

Keywords: CCS; feasibility; CHP; steel mill; GTCC; biomass

1. Introduction

It has been generally stated that climate change is one of the most serious environmental threats that humankind is facing and that greenhouse gas emissions (GHG's) should be reduced in every field of activities. Carbon capture and storage (CCS) is under extensive research and development globally. In Finland, CCS has been a part of the discussions regarding mitigation of climate change since the nineties, but has been considered expensive and not mature enough in comparison to other measures for reducing CO2 emissions. With CCS it is possible to reach even negative emissions through bio-CCS, which is defined in this paper as capturing CO2 from biomass combustion and storing it constantly isolated from atmosphere.

Significant improvements on the energy production efficiency of CCS processes are needed. One of the key solutions for that is combined heat and power (CHP, a.k.a co-generation) where over 90 % process efficiency is achievable if large heat distribution system and relatively continuous heat consumption (or storage) in that system exist. In Finland, both biomass fuels and CHP has been utilised for decades in industry and for district heating.

Besides energy production, CCS is a key technology for significant CO2 emission reductions for many industrial applications such as the steel industry. Due to the large unit sizes, relatively high CO2 concentrations, existing utilisation of pure oxygen and significant recoverable process heat amounts, CCS may become profitable in steel mills considering that the costs for CO2 emissions would rise significantly in the future.

This paper describes implications of applying carbon capture and storage in combined heat and power (CHP) production and in steel industry through three applications which were studied in different operational situations. Utilisation of relatively low temperature process heat from capture plant, air separation unit or CO2 compression in district heating system and/or industrial solutions offers significant potential to increase overall efficiency and feasibility of CCS processes. On the other hand, heat can be recovered from the existing industrial processes in high enough temperatures for CCS processes, for instance solvent regeneration. In the case studies the whole CCS chain, including CO2 capture, processing,

transport and storage, was included. The properties of reference plants and CHP systems are based on the real operational CHP units and steel mill in Finland.

2. Background

2.1 Description of the system modeling and the overall approach

The economics of CCS are evaluated from investor's (local energy company or steel mill operator) point of view including the effects on the existing energy system or steel mill processes. In the modeled CHP cases the potential investor for CO2 capture is also the owner of existing CHP plants in respective district heat (DH) network and therefore the impacts are important to take into account when feasibility of CCS is considered. In the steel mill application emissions and cost of the steelmaking with carbon capture processes are compared to the situation without the carbon capture with constant production levels of the steel mill.

Effect of CCS on greenhouse gas (GHG) emissions and operation economics of the CCS cases are compared to the reference system with varying parameters of operation. Regarding the GHG emissions, besides the site emissions, the main effects on global GHG emissions are also taken into account by using system modeling and streamlined LCA. The cases and results presented in this paper are selected from the large amount of case studies executed in both, the CCS Finland project and currently ongoing national CCS Programme in Finland. [1]

In the case studies the whole CCS chain, including CO2 capture, processing, transport and storage, was included. Carbon capture processes were modeled using Aspen Plus and Prosim process modeling software and the results were used in CCS plant economics toolkit (a Microsoft Excel-based system model CC-Skynet™ developed by VTT Technical Research Centre of Finland). In the toolkit, the profitability of each case can be optimized according to different market situations by adjusting plants operation and the most significant input values in the limits given for each variable. In addition to plant and case specific technical inputs, the economic parameters are given, including required interest rates, studied time frames, fuel taxes, subsidies and market prices for different fuels, electricity, heat and CO2 emission allowances (in the EU ETS) as well as CCS related costs, for example required investment, transportation costs, prices for solvents and impact of CCS on other fixed and variable operational costs. Other additional operating costs are estimated to consist mainly of fixed costs because most of the variable operating costs were estimated separately. Fixed operating costs include for example personnel and maintenance costs.

As there is no storage capacity in Finland the captured CO2 has to be transported and stored abroad. The storage phase in this study is evaluated according to Teir et al. [2] and the CO2 transportation including costs related are assumed according to model presented in Kujanpaa et al. [3] Ship transportation from Finland is the most promising first phase solution for transporting of CO2 to a storage site outside Finland. For ship transportation CO2 has to be pressurized and cooled down to approximately 6,5 bar and -52°C. To reach these conditions with normal cooling water temperatures CO2 compression and flash purification is needed in several stages. CO2 stream has to be cooled between the compression stages and some of the heat can be recovered for district heating. CO2 is cooled down to 15°C between the compression stages. Some of this low temperature level heat can be utilized to preheat the return stream from district heating network.

2.2 Description of the studied CCS applications

The case studies presented in this paper include three main applications which were studied in different operational situations. The properties of reference plants and CHP systems are based on the real operational CHP units and steel mill in Finland.

The first presented application is retrofit of about 1000 MWfuel CHP plant with post combustion capture technology. Natural gas fired GTCC plant is part of relatively large district heating network including also other CHP units in the same network. The plant is situated on the coastal area of Southern Finland and it emits approximately 1.3 Mtn CO2 / year. The solvent for post combustion capture in this application was MEA. Retrofitting of CCS to the GTCC plant would change for example maximum electricity and heat production of the plant and in addition affect also on the utilisation rate of the GTCC plant and other plants in the network. The other plants of the network are divided to three groups which are: other GTCC plant, coal fired CHP plants and district heating boilers ("DH boilers", including heat production by coal, oil and gas). Depending on the given utilisation rates of the CHP plants, share of condensing production or auxiliary cooling in these plants and share of coal, oil and gas in DH boilers the need for DH boilers is calculated based on the variables for CHP plants and given heat consumption in the network.

The second application is a greenfield about 500 MWfael CHP plant situated on the coast of the Gulf of Bothnia and emitting approximately 1.5 Mtn CO2 / year. The plant is based on a modern CFB-boiler which is equipped with oxy-fuel technology in the CCS case. The cases have been studied with different fuel-shares with and without CCS consisting of 100 % biomass, 100 % peat and biomass-peat co-firing. The plant is connected to the existing district heating network where older 295 MWfael CHP plant (fired with 50 % peat and 50 % biomass) already exists. Another plant and limited district heat consumption in the area limits the benefits obtained from CCS heat recovery. District heat selling within the studied system boundary is 1400 GWh/a, but net electricity production varies from case to case. In the reference case without CCS the existing CHP plant produces district heat and back-pressure electricity with maximum load and number of heavy-oil fired district heating plants provide the additional heat needed within the system for example during the winter peak load hours. In cases with CCS the existing CHP plant and the new plant produce district heat and back-pressure electricity with given utilisation rates which must be in total at least sufficient to satisfy the heat demand. In addition, condensing electricity is produced at the new plant depending on the given utilisation rate (market situation which defines the profitability of condensing production). At cases with CCS the utilisation of heat recovered from CCS is dependent on the given utilisation rates of the plants.

The third application is an integrated steel mill situated on the coast of the Gulf of Bothnia and emitting approximately 4.0 Mtn CO2 / year altogether. A single capture unit processing flue gas streams from the power plant on site and the hot stoves of the mill are installed for post combustion capture and implications of different capture amounts, different solvents and process integration levels are compared to the base case steel production with varying operational parameters. Technical details of the studied steel mill and CCS cases are presented in Arasto et al. [4]. Results of all the conducted economic case studies related to this mill are presented in Tsupari et al. [5] as well as related emissions. In this paper, cases 2 and 3 presented in Tsupari et al. [5] are compared to reference case with the focus on the benefits of recovered process heat. Process heat is utilized also as district heat but heat consumption in the district heat network is smaller than the amount of recoverable process heat in the mill. Capture is modeled with three different solvent scrubbing technologies namely 30% MEA, the Siemens amino acid salt (referred in this paper as "Advanced solvent") and hypothetical solvent, able to be regenerated at a significantly lower temperature than baseline MEA (referred in this paper as "Low-T solvent").

3. Main results

The goal was to evaluate annual cash flows within the system boundary in different CCS cases and compare the balances with the base cases without CCS. The main results are presented in a set of tables and figures which present the overall annual costs and profit of the entire production system, with and without CCS as well as heat recoveries impact on the break even points (BeP's) for CO2 emission allowances where CCS becomes feasible over the reference case. The market prices used in the study are general assumptions and do not reflect price estimations of the operators of the studied CHP units and the steel mill.

3.1 Retrofit of1000 MWfuel CHP plant

The CHP plant emits approximately 1.3 Mtn CO2 / year of which 90 % is captured in CCS cases. In Table 1 is presented the modeled energy balance for MEA solvent based on [6] and assumptions made by the authors.

Table 1. The modeled energy balance for MEA solvent.

without CCS with CCS

Operation mode CHP Power CHP Power

Fuel input, MW (HHV) 1 020 1 020 1 020 1 020

Power, MWnet 412 519 367 397

District heat, MW 443 0 325 0

from turbine 443 0 302 0

from capture&CPU 0 0 23 0

Overall efficiency 84 % 51 % 68 % 39 %

Power 40 % 51 % 36 % 39

With the following market prices: electricity 120 €/MWh, district heat 60 €/MWh and CO2 emission allowance in EU ETS of 80 €/tn, the plant operation with and without heat recovery from CCS was studied in two fuel price scenarios. The peak load utilisation rates of the plants were optimised based on the total profit of the system in presented market situations. In both scenarios the break even prices for CCS feasibility were defined. The difference between the break even prices indicates the cost benefits of CCS heat recovery in CHP system and it is presented in Figure 1. With lower prices of electricity (than used 120 €/MWh in which the plant operation was optimised) the benefits of CCS heat recovery in CHP increase. However, the more the electricity market price differs from the modelled electricity market price, the higher the uncertainties of the results are due to the effect of the modified market conditions on the plant operation rates.

Difference in BeP [€/tn] with and without CCS heat recovery

Price of electricity [C/MWh]

Figure 1. The difference between the break even prices of EUA in plant operation with and without heat recovery from CCS in two fuel price scenarios. The values indicate the cost benefits of CCS heat recovery in a CHP system. Negative values indicate that heat recovery from CCS is unprofitable in terms of overall system economics with high electricity prices and due to reduced need for

normal CHP production (reduced electricity production).

3.2 Greenfield 500 MWfud CHP plant

The CHP plant emits approximately 1.5 Mtn CO2 / year of which about 99 % is captured by advanced oxy-fuel application in CCS cases. In Table 2 is presented the modeled energy balance based on process modeling for plant operation with 100 % peat. Very high overall process efficiency is achievable in the oxy-fuel based CHP application if process heat can be utilized in district heating. If flue gas condensers are utilized (as typically in CCS applications) the overall process efficiencies on a LHV basis can exceed even 100% with wet fuels such as biomass and peat (overall moisture content about 50 %).

The case has been studied with different fuel-shares with and without CCS consisting of 100 % biomass, 100 % peat and biomass-peat co-firing (Note. In the studies it is assumed that the economic incentive for negative CO2 emission is included in EU ETS for Bio-CCS). Large variation in the fuel mix effects on plant design, investment and operational parameters and the use of biomass is assumed to increase the plant investment and plant operating costs. In figure 2 is presented the costs from the operator point of view for different fuel options with and without CCS. [7]

Table 2. The modeled energy balance for plant operation with 100 % peat.

without CCS with CCS

Operation mode CHP Power CHP Power

Fuel input, MW1) 576 576 576 576

Power, MWnet 165 213 125 163

District heat, MW 272 0 352 0

from turbine 272 0 266 0

from ASU&CPU 0 0 86 0

Overall efficiency1-1 76 % 37 % 83 % 28 %

Power 29 % 37 % 22 % 28 %

1) Fuel thermal input is based on fuel HHV

Annual operating costs and incomes, M€/a

Figure 2. The cost structure with EUA price of 23 €/tn, CO2, electricity price of 60 €/MWh and district heat price 50 €/MWh for different fuel cases. Fuel purchase prices are 12 €/MWh for peat and 18 €/MWh for biomass. CCS is not feasible in comparison to respective base cases with the given input values. The highest profit is gained by 100% peat firing. However, all the cases without CCS are economically profitable, mainly due to good economics of CHP in general. [7]

The most economical solution is depended mainly on prices of electricity and EUA, fuel costs and estimated peak load hours, which all are uncertain and also interdependent. In table 3, the break even prices (BEP) and costs of CO2 avoided (COA), €/tn, with different price levels are presented (Note. Also EUA price is presented as input value due to its indirect effect on results). As it can be seen, CCS in connection to CHP and biomass combustion results relatively low break even prices compared to for example with the break even prices defined for condensing power plants. For Finnish condensing power plants break even prices of 70 - 100 €/tn are presented by Teir et al. [2] even if plant size is larger in condensing case. Even though in the cases presented in Table 3 the lowest BEP can be achieved with Bio-

CCS, the most profitable CCS option of these cases is co-firing, due to the good profitability of co-firing in general comparing to dedicated biomass firing. [7]

Table 3. Break even prices (BEP) and costs of CO2 avoided (COA), €/tn, in different CCS cases in comparison with respective base cases with two sets of price parameters.

Case: 100 % peat with CCS co-firing with CCS 100 % bio with CCS

BEP COA BEP COA BEP COA

CO2: 23 €/tn, Electricity: 60 €/MWh, DH: 50 €/MWh, Bio: 18 €/MWh 55 70 54 68 53 66

CO2: 60 €/tn, Electricity: 90 €/MWh, DH: 60 €/MWh, Bio: 18 €/MWh 61 78 60 76 59 73

To highlight the benefits of CHP in CCS systems the cost of electricity production with different EUA and district heat prices in the peat fired cases is presented in Figure 3. In this example the overall production costs of CHP are first calculated with different EUA prices after which the income from DH sales is extracted with different prices of DH. The remaining part is then divided by total net electricity production. This cost is compared to electricity production cost of exactly the same plant, but utilising only the condensing power production (higher electricity production but without district heat production). With future higher EUA prices the impacts of the EUA price on DH price level should also be taken into account.

Figure 3. The cost of electricity production with different EUA and district heat prices. Typically production costs for CHP electricity are lower than for power only. Similarly the costs of CCS CHP are more competitive than with CCS power only.

3.3 Integrated steel mill

The capture amounts studied in this paper were about 2 MtCO2/a which accounts for approximately 50 % of the whole site emissions. In Figure 4 the effect of CCS on the total costs in comparison with the reference case are presented using an EUA price of 60 €/tn and electricity price of 80 €/MWh for three different solvents. With these prices CCS cases 2 and 3 would be more profitable than the reference case with "Advanced" and "low-T" solvents, but not with MEA. The most economic option would be "Advanced" solvent but in general the results with "Advanced" solvent and "low-T" solvent are near to

each other. The impact of heat recovery from steel mill processes to solvent regeneration can be seen from the difference between case 3 and 2. The economic benefit with presented market situation is several millions of euros annually, depending on the solvent. A solvent, which could be regenerated using low temperature process heat, would probably result in significant advantages in the overall economics of CCS in the process industry, where substantial amounts of process heats are available in liquid phase.

Figure 4. The impact of process heat utilisation on the cost reduction achievable by CCS in comparison with the reference case using EUA price of 60 €/tn and electricity price of 80 €/MWh for three different solvents. The savings through heat recovery can be up to several millions of euros annually depending on the solvent and, for example, prices of electricity and EUA's.

4. Conclusions

Utilisation of CHP in general is a cost effective technology to improve overall energy efficiency, reduce fossil fuel consumption and mitigate climate change. Application of CCS in the CHP systems results further benefits which can be very significant depending on case specific options. The costs for CCS are heavily dependent not only on the characteristics of the facility but especially in the CHP applications also on the operational environment and the chosen system boundaries and assumptions. For example, the fuels replaced in the existing district heat network by application of new CHP plant with CCS are essential in terms of overall economics and emissions. In addition the impacts of new plant on the electricity production of the existing CHP plants in the network need to be taken into account when feasibility of CCS is evaluated. The optimal solution from an investor's point of view depends on multiple factors, electricity price and EU-ETS price being the dominant ones.

In general, it can be concluded the EU-ETS price and electricity prices prospected in the near future do not make the CCS investment yet easily feasible. The break even price for CO2 allowances, which would make CCS feasible, may be even higher than often estimated if electricity price will increase more than estimated due to increasing CO2 prices. This would emphasis the importance of the development of the

efficiencies of the CCS processes and applying CCS in the cases where extensive heat integration is possible.

According to presented results, in combined heat and power plants, significant improvements can be achieved with heat integration, especially, in the production of district heat. Economically the most feasible CCS solutions are achieved in the cases where heat from CCS plant can be utilized in district heating network but plant can be operated also in condensing mode to achieve high peak load hours, which are necessary in terms of investment payback time.

The feasibility of CCS can also be optimized by using the new operational options that CCS brings especially in the CHP applications. For instance, heat recovery from oxy-fuel case enables more flexibility for condensing power production in CHP plants as steam need from turbine for DH is decreased comparing to case without CCS. This may be feasible in the case of low electricity prices. On the other hand, oxygen production could be reduced and capture plant bypassed during periods of peak electricity prices.

In Finland, CHP plants are generally of moderate size and often situated in central Finland, which makes them less attractive due to large distances to potential ship terminals. In the near future particularly large, new and flexible combined heat and power (CHP) plants, which can burn coal, biomass or peat, are seen as promising candidates for CCS in Finland. Oxy-fuel combustion is seen as a promising technology for Finland, both in terms of domestic CCS applications and as an opportunity for Finnish technology developers.

The studied impact of heat recovery from steel mill processes to solvent regeneration can result economic benefit of several millions of euros annually. The presented figure for the steel mill application is based on the mapped heat recovery potential in the studied steel mill. Because extensive utilisation of low temperature heat streams in the mill has not been relevant issue before, the amount of recoverable heat streams, especially in low temperatures, are unknown as well as the investments required for utilisation of these streams. If the studied "Low-T" solvent could be developed and commercialized, even more low level waste heat than estimated in presented figure could be utilizable in the mill. This might lead to improvements in the feasibility of CCS if heat recovery can be implemented with low investment.

Acknowledgements

This paper is published as a part of research in Finnish national technology programmes Climbus and CCSP. The main financers including among others Tekes (the Finnish Funding Agency for Technology and Innovation), Fortum, Helsingin Energia and Ruukki are sincerely acknowledged. The authors want to acknowledge also Hannu Mikkonen, Lotta Sorsamaki and Sebastian Teir from VTT Technical Research Centre of Finland for their contribution in the work.

References

[1] Carbon Capture and Storage (CCSP) program. http://www.cleen.fi/fi/ccsp (available October 2012, in Finnish).

[2] Teir, S., Arasto, A., Tsupari, E., Koljonen, T., Karki, J., Kujanpaa, L., et al. 2011. Hiilidioksidin talteenoton ja varastoinnin (CCS:n) soveltaminen Suomen olosuhteissa. Espoo, VTT. 76 s. + liitt. 3 s. VTT Tiedotteita - Research Notes; 2576 ISBN 978-95138-7697-5; 978-951-38-7698-2

[3] Kujanpaa, L., Rauramo, J., Arasto, A. 2011. Cross-border CO2 infrastructure options for a CCS demonstration in Finland. Energy Procedia. Elsevier, vol. 4, ss. 2425-2431 doi: 10.1016/j.egypro.2011.02.

[4] Arasto, A., Tsupari, E. , Karki, J., Pisila, E., Sorsamaki, L., 2012. Post-Combustion Capture of CO2 at an Integrated Steel Mill -Part I: Technical Concept Analysis. International Journal of Greenhouse Gas Control January 2012. http://dx.doi.org/10.1016/j.ijggc.2012.08.018

[5] Tsupari, E., Karki, J., Arasto, A., Pisila, E., 2012. Post-Combustion Capture of CO2 at an Integrated Steel Mill -Part II Economic Feasibility. International Journal of Greenhouse Gas Control January 2012. http://dx.doi.org/10.1016/j.ijggc.2012.08.017

[6] Laine, M. 2011. Effects of carbon capture on an existing combined cycle gas turbine power plant. Master's Thesis. Aalto University.

[7] Tsupari, E., Karki, J., Arasto, A., 2011. Feasibility of BIO-CCS In CHP Production - A Case Study of Biomass Cofiring Plant in Finland. Presented in Second international workshop on biomass & carbon capture and storage. October 25th and 26th 2011, Cardiff Wales.