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Abstract: Carbon dioxide (CO2) capture and storage (CCS) in unmineable coal seams is regarded as one of the possible approaches to mitigate the ever increasing CO2 concentration in the atmosphere resulting from human activities since the Industrial Revolution. Injection of CO2 into unmineable coal seams not only provides a solution for long term storage of CO2 but it also provides the added advantage of enhancing coalbed methane recovery. Adsorption is the main trapping mechanism for CO2 storage in coal seams where it constitutes to about 95–98% of total storage. Other trapping mechanisms include gas trapped within the matrix structure, free gas and CO2 trapped as a solute in the pore water. Coal is usually highly heterogeneous and contains pores of different sizes: micropores, mesopores and macropores. The physical properties such as permeability, which usually changes with depth and the degree of cleating, complicates the storage capacity estimation process. Injection of highly dense phase CO2 may offer higher storage capacity because of its higher density compared to gaseous CO2. However, there is a lack of verified CO2 storage capacity estimation methodology for coalbeds. Computing storage potential of CO2 is not straightforward due to the highly variable coal properties even in the same coal seam. Therefore, in this paper a statistical framework for estimating the CO2 storage capacity in coal seams is presented with the emphasis on highly dense CO2 conditions. The approach is based on earlier studies, which utilise important in situ parameters to estimate storage capacity in coal seams. These parameters include volatile matter content, moisture, ash, pressure and temperature. Furthermore, several widely used adsorption models for single- and multi-component gas are reviewed. The ability of the various models in predicting the adsorption capacity for different coal types and under various in situ conditions was examined. Dataset consists of adsorption data representing 69 coal types having vitrinite reflectance ranging from 0.25% to 3.86%. Results of analyses of this dataset showed that better estimation can be obtained by expressing adsorption capacity as a power function of pressure rather than assuming a linear relationship between adsorption capacity and pressure while keeping other important parameters unchanged. [Copyright &y& Elsevier]

A safety increase in the energy supply and limiting the energy resources importation in the circumstances of an accelerated economic development can be insured through a strategy to develop Romania’s energy development. This requirement can be achieved on the one hand, through the deployment of a policy supported by energy conservation, energetic efficieny increase which leads to disconnecting the economic development rythm and the evolution of energy consumption and on the other hand increase of the renewable energy resources efficiency. Developing the renewable energy resources potential gives real premisses to achieve strategical goals regarding the increase of safety in energy supply by varying the sources and decreasing the percentage of energy resources importation and developing on the long run the energetic department and protecting the environment. In this paper we present a study regarding the strategic goals on the short, medium and long run and the development level, the use and the potential of energy sources. [ABSTRACT FROM AUTHOR]

The European iNTeg-Risk project is a large-scale integrated project aimed at improving the management of emerging risks related to new technologies in European industry. The project aims to build a new management paradigm for emerging risks as a set of principles supported by a common language, agreed tools and methods, and key performance indicators, all integrated into a single framework. It is using a number of Emerging Risk Representative Applications (ERRAs), or case studies, to inform the development of the framework; one of which concerns the carbon capture and storage (CCS) process. This paper describes the iNTeg-Risk CCS ERRA. Relevant hazards and properties of carbon dioxide are described and the emerging risks from CCS are discussed. Three new tools have been developed or trialled within the ERRA. These are: the DyPASI methodology for taking account of atypical (not usually identified) events during hazard identification; a methodology for including the time dimension in a risk assessment; and life-cycle approaches for risk management and communication. For CCS, the risk assessment needs to include both short-term potential accidents from capture, transport or injection, as well as very long-term risks from storage. Knowledge gaps which are generic to emerging risks are also identified. [ABSTRACT FROM AUTHOR]

Abstract: Climate change is fast becoming the major environmental and energy concern worldwide. There is a major dilemma between the continued reliance on fossil fuel for our energy supply and the pressing need to address the problem of greenhouse gas (GHG) emissions from combustion process. This paper reviews the potential for carbon capture and storage (CCS) as a part of the climate change mitigation strategy for the Malaysian electricity sector using a technology assessment framework. The nation''s historical trend of high reliance on fossil fuel for its electricity sector makes it a prime candidate for CCS adoption. The suitability and practicality of the technology was reviewed from a broad perspective with consideration of Malaysia-specific conditions. It is apparent from this assessment that CCS has the potential to play an important role in Malaysia''s climate change mitigation strategy provided that key criteria are fulfilled. [Copyright &y& Elsevier]

Carbon capture, transport and storage (CCS) is a very active field of research, because of its potential to make large reductions of emissions from fossil fuel combustion relevant to climate change. This paper reviews the recent and current work on practical injections of CO2 as research tests for storage projects and specifically focuses on industrial-scale or relevant injections into saline formations (about 1 Mt CO2 per year). All injection projects around the world have been reviewed, and 20 are reported to compile, depth, reservoir quality and injectivity, cost, and rate. This shows that testing of injection is concentrated onshore; however the projects with the highest total CO2 storage estimate are offshore. Pipeline transport systems are mostly used for the large projects. Formations targeted in the injection process are sandstone or carbonate. In the majority of cases initial projections of injectivity are confirmed in tests. A variety of monitoring techniques are used in all projects, these have detected CO2, but have not shown unexpected CO2 movement. Practical experiences of CO2 injection operations therefore suggest that similar operations can be successfully carried out in the saline formations of the UK North Sea and other large sedimentary basins. [ABSTRACT FROM AUTHOR]

The installations of CO2 capture from flue gases using chemical absorption require a supply of large amounts of heat into the system. The most common heating medium is steam extracted from the cycle, which results in a decrease in the power unit efficiency. The use of heat needed for the desorption process from another source could be an option for this configuration. The paper presents an application of gas-air systems for the generation of extra amounts of energy and heat. Gas-air systems, referred to as the air bottoming cycle (ABC), are composed of a gas turbine powered by natural gas, air compressor and air turbine coupled to the system by means of a heat exchanger. Example configurations of gas-air systems are presented. The efficiency and power values, as well as heat fluxes of the systems under consideration are determined. For comparison purposes, the results of modelling a system consisting of a gas turbine and a regenerative exchanger are presented. [ABSTRACT FROM AUTHOR]

Abstract: Carbon dioxide is more and more pointed out as one of the factors mostly responsible of climate changes. As a consequence the reduction of CO2 emissions, especially in the energy generation field, is becoming a worldwide must. This paper presents an overview on the main issues that are expected to affect, from this standpoint, power generation scenario and a spur for a critical comparison among ways to capture CO2 by proposing new aspects to be considered within the evaluation criteria. In particular attention is drawn on the fully innovative opportunities that are offered by Molten Carbonate Fuel Cells (MCFCs) as a unique option suitable to effectively combine carbon capture from thermal plants and typical benefits of hydrogen and fuel cell power generation. As an example, such a new option is compared with one of the most common technologies forecast for reducing carbon dioxide emissions and relevant results are shortly presented. [Copyright &y& Elsevier]

Carbon dioxide capture and storage (CCS) links together technologies that separate carbon dioxide (CO2) from fixed point source emissions and transport it by pipeline to geologic reservoirs into which it is injected underground for long-term containment. Previously, models have been developed to minimize the cost of a CCS infrastructure network that captures a given amount of CO2. The CCS process can be costly, however, and large-scale implementation by industry will require government regulations and economic incentives. The incentives can price CO2 emissions through a tax or a cap-and-trade system. This paper extends the earlier mixed-integer linear programming model to endogenously determine the optimal quantity of CO2 to capture and optimize the various components of a CCS infrastructure network, given the price per tonne to emit CO2 into the atmosphere. The spatial decision support system first generates a candidate pipeline network and then minimizes the total cost of capturing, transporting, storing, or emitting CO2. To illustrate how the new model based on CO2 prices works, it is applied to a case study of CO2 sources, reservoirs, and candidate pipeline links and diameters in California. [ABSTRACT FROM AUTHOR]

Abstract: The oxy-fuel process is one of three carbon capture technologies which supply CO2 ready for sequestration – the others being post-combustion capture and IGCC with carbon capture. As yet no technology has emerged as a clear winner in the race to commercial deployment. The oxy-fuel process relies on recycled flue gas as the main heat carrier through the boiler and results in significantly different flue gas compositions. Sulphur has been shown in the study to have impacts in the furnace, during ash collection, CO2 compression and transport as well as storage, with many options for its removal or impact control. In particular, the effect of sulphur containing species can pose a risk for corrosion throughout the plant and transport pipelines. This paper presents a technical review of all laboratory and pilot work to identify impacts of sulphur impurities from throughout the oxy-fuel process, from combustion, gas cleaning, compression to sequestration with removal and remedial options. An economic assessment of the optimum removal is not considered. Recent oxy-fuel pilot trials performed in support of the Callide Oxy-fuel Project and other pilot scale data are interpreted and combined with thermodynamic simulations to develop a greater fundamental understanding of the changes incurred by recycling the flue gas. The simulations include a sensitivity analysis of process variables and comparisons between air fired and oxy-fuel fired conditions - such as combustion products, SO3 conversion and limestone addition. [Copyright &y& Elsevier]

In this paper we show the effects of expanding the system when evaluating well-to-wheel (WTW) CO2 emissions for biomass-based transportation, to include the systems surrounding the biomass conversion system. Four different cases are considered: DME via black liquor gasification (BLG), methanol via gasification of solid biomass, lignocellulosic ethanol and electricity from a biomass integrated gasification combined cycle (BIGCC) used in a battery-powered electric vehicle (BPEV). All four cases are considered with as well as without carbon capture and storage (CCS). System expansion is used consistently for all flows. The results are compared with results from a conventional WTW study that only uses system expansion for certain co-product flows. It is shown that when expanding the system, biomass-based transportation does not necessarily contribute to decreased CO2 emissions and the results from this study in general indicate considerably lower CO2 mitigation potential than do the results from the conventional study used for comparison. It is shown that of particular importance are assumptions regarding future biomass use, as by expanding the system, future competition for biomass feedstock can be taken into account by assuming an alternative biomass usage. Assumptions regarding other surrounding systems, such as the transportation and the electricity systems are also shown to be of significance. Of the four studied cases without CCS, BIGCC with the electricity used in a BPEV is the only case that consistently shows a potential for CO2 reduction when alternative use of biomass is considered. Inclusion of CCS is not a guarantee for achieving CO2 reduction, and in general the system effects are equivalent or larger than the effects of CCS. DME from BLG generally shows the highest CO2 emission reduction potential for the biofuel cases. However, neither of these options for biomass-based transportation can alone meet the needs of the transport sector. Therefore, a broader palette of solutions, including different production routes, different fuels and possibly also CCS, will be needed. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Using CO2/N2 gas separation membranes for post-combustion capture, the most important problem is how to create the driving force efficiently because the feed flue gas has only ambient pressure and a relatively low CO2 content. In order to fulfill the separation target – 95mol% CO2 purity and appropriate degree of CO2 separation – multi-stage systems are necessary using feasible membranes. This paper describes a detailed parametric study for multi-stage membrane systems used in a coal-fired power plant. According to the above-mentioned boundary conditions, the investigation process was divided into two steps: (a) energy consumption and (b) capture cost analyses. In the first step, by varying the position of the compressors and vacuum pumps and recycling the flue gas to the feed side, cascade variants were developed and analyzed in detail. The cascade system was integrated in the 600MW North Rhine-Westphalia reference power plant and compared with the chemical absorption process. In the second step, an economic model was developed to make a further analysis of the cascade system. A correlation was established between the membrane parameters (selectivity, permeability) and system performance (energy consumption, capture cost). [Copyright &y& Elsevier]

This paper presents the Life Cycle Assessment (LCA) analysis concerning the selected options of supercritical coal power units. The investigation covers a pulverized power unit without a CCS (Carbon Capture and Storage) installation, a pulverized unit with a "post-combustion" installation (MEA type) and a pulverized power unit working in the "oxy-combustion" mode. For each variant the net electric power amounts to 600 MW. The energy component of the LCA analysis has been determined. It describes the depletion of non-renewable natural resources. The energy component is determined by the coefficient of cumulative energy consumption in the life cycle. For the calculation of the ecological component of the LCA analysis the cumulative CO2 emission has been applied. At present it is the basic emission factor for the LCA analysis of power plants. The work also presents the sensitivity analysis of calculated energy and ecological factors. [ABSTRACT FROM AUTHOR]

Abstract: The calculus of communicating systems, CCS, was introduced by Robin Milner as a calculus for modelling concurrent systems. Subsequently several techniques have been developed for analysing such models in order to get further insight into their dynamic behaviour. In this paper we present a static analysis for approximating the control structure embedded within the models. We formulate the analysis as an instance of a monotone framework and thus draw on techniques that often are associated with the efficient implementation of classical imperative programming languages. We show how to construct a finite automaton that faithfully captures the control structure of a CCS model. Each state in the automaton records a multiset of the enabled actions and appropriate transfer functions are developed for transforming one state into another. A classical worklist algorithm governs the overall construction of the automaton and its termination is ensured using techniques from abstract interpretation. [Copyright &y& Elsevier]

Abstract: In this paper, different electricity demand scenarios for Spain are presented. Population, income per capita, energy intensity and the contribution of electricity to the total energy demand have been taken into account in the calculations. Technological role of different generation technologies, i.e. coal, nuclear, renewable, combined cycle (CC), combined heat and power (CHP) and carbon capture and storage (CCS), are examined in the form of scenarios up to 2050. Nine future scenarios corresponding to three electrical demands and three options for new capacity: minimum cost of electricity, minimum CO2 emissions and a criterion with a compromise between CO2 and cost (CO2-cost criterion) have been proposed. Calculations show reduction in CO2 emissions from 2020 to 2030, reaching a maximum CO2 emission reduction of 90% in 2050 in an efficiency scenario with CCS and renewables. The contribution of CCS from 2030 is important with percentage values of electricity production around 22–28% in 2050. The cost of electricity (COE) increases up to 25% in 2030, and then this value remains approximately constant or decreases slightly. [Copyright &y& Elsevier]

Abstract: This paper investigates new possibilities and synergy effects for an oxy-fuel fired polygeneration scheme (transportation fuel and electricity) with carbon capture and co-firing of biomass. The proposed process has the potential to make the oxy-fuel process more effective through a sub-stoichiometric combustion in-between normal combustion and gasification, which lowers the need for oxygen within the process. The sub-stoichiometric combustion yields production of synthesis gas, which is utilised in an integrated synthesis to dimethyl ether (DME). The process is kept CO2 neutral through co-combustion of biomass in the process. The proposed scheme is simulated with a computer model with a previous study of an oxy-fuel power plant as a reference process. The degree of sub-stoichiometric combustion, or amount of synthesis gas produced, is optimised with respect to the overall efficiency. The maximal efficiency was found at a stoichiometric ratio just below 0.6 with the efficiency for the electricity producing oxy-fuel process of 0.35 and a DME process efficiency of 0.63. It can be concluded that the proposed oxygen lean combustion process constitutes a way to improve the oxy-fuel carbon capture processes with an efficient production of DME in a polygeneration process. [Copyright &y& Elsevier]

Abstract: This paper assesses the three leading technologies for capture of CO2 in power generation plants, i.e., post-combustion capture, pre-combustion capture and oxy-fuel combustion. Performance, cost and emissions data for coal and natural gas-fired power plants are presented, based on information from studies carried out recently for the IEA Greenhouse Gas R&D Programme by major engineering contractors and process licensors. Sensitivities to various potentially significant parameters are assessed. [Copyright &y& Elsevier]

Abstract: Understanding biochemical pathways is one of the biggest challenges in the field of molecular biology nowadays. Computer science can contribute in this area by providing formalisms and tools to simulate and analyse pathways. One formalism that is suited for modelling concurrent systems is Milner''s Calculus of Communicating Systems (CCS). This paper shows the viability of using CCS to model and reason about biochemical networks. As a case study, we describe the regulation of lactose operon. After describing this operon formally using CCS, we validate our model by automatically checking some known properties for lactose regulation. Moreover, since biological systems tend to be very complex, we propose to use multiple descriptions of the same system at different levels of abstraction. The compatibility of these multiple views can be assured via mathematical proofs of observational equivalence. [Copyright &y& Elsevier]

Abstract: Model checking is a formal technique for proving the correctness of a system with respect to a desired behavior. However, deadlock detection via model checking is particularly difficult for the following two problems: (i) the state explosion problem, due to the exponential increase in the size of a finite state model as the number of system components grows; and (ii) the output interpretation problem, as often counter-examples are so long that they are hard to understand. The aim of this paper is to solve both problems by using heuristic-based search strategies. We have realized DELFIN+ (DEadLock FINder) a tool supporting efficient deadlock detection in CCS processes. We have used this tool to verify a sample of CCS processes, in order to evaluate the method on them. [Copyright &y& Elsevier]

Abstract: This paper describes in detail how to bridge the gap between theory and practice when implementing in Maude structural operational semantics described in rewriting logic, where transitions become rewrites and inference rules become conditional rewrite rules with rewrites in the conditions, as made possible by the new features in Maude 2. We validate this technique using it in several case studies: a functional language Fpl (evaluation and computation semantics), an imperative language WhileL (evaluation and computation semantics), Kahn’s functional language Mini-ML (evaluation or natural semantics), Milner’s CCS (with strong and weak transitions), and Full LOTOS (including ACT ONE data type specifications). In addition, on top of CCS we develop an implementation of the Hennessy–Milner modal logic for describing local capabilities of processes, and for LOTOS we build an entire tool where Full LOTOS specifications can be entered and executed (without user knowledge of the underlying implementation of the semantics). We also compare this method based on transitions as rewrites with another one based on transitions as judgements. [Copyright &y& Elsevier]

Abstract: Model checking is a formal technique for proving the correctness of a system with respect to a desired behavior. This is accomplished by checking whether a structure representing the system (typically a labeled transition system) satisfies a temporal logic formula describing the expected behavior. Model checking has a number of advantages over traditional approaches that are based on simulation and testing: it is completely automatic and when the verification fails it returns a counterexample that can be used to pinpoint the source of the error. Nevertheless, model checking techniques often fail because of the state explosion problem: transition systems grow exponentially with the number of components. The aim of this paper is to attack the state explosion problem that may arise when looking for deadlocks in concurrent systems described through the calculus of communicating systems. We propose to use heuristics-based techniques, namely the A* algorithm, both to guide the search without constructing the complete transition system, and to provide minimal counterexamples. We have realized a prototype tool to evaluate the methodology. Experiments we have conducted on processes of different size show the benefit from using our technique against building the whole state space, or applying some other methods. [Copyright &y& Elsevier]

Abstract: This paper confirms a conjecture of Bergstra and Klop''s from 1984 by establishing that the process algebra obtained by adding an auxiliary operator proposed by Hennessy in 1981 to the recursion free fragment of Milner''s Calculus of Communicating Systems is not finitely based modulo bisimulation equivalence. Thus, Hennessy''s merge cannot replace the left merge and communication merge operators proposed by Bergstra and Klop, at least if a finite axiomatization of parallel composition modulo bisimulation equivalence is desired. [Copyright &y& Elsevier]

Geological carbon storage is an effective method capable of reducing carbon dioxide (CO2) emissions at significant scales. Subsurface reservoirs with sealing caprocks can provide long-term containment for the injected fluid. Nevertheless, CO2 leakage is a major concern. The presence of abandoned wells penetrating the reservoir caprock may cause leakage flow-paths for CO2 to the overburden. Assessment of time-varying leaky wells is a need. In this paper, we propose a new semi-analytical approach based on pressure-transient analysis to model the behavior of CO2 leakage and corresponding pressure distribution within the storage site and the overburden. Current methods assume instantaneous leakage of CO2 occurring with injection, which is not realistic. In this work, we employ the superposition in time and space to solve the diffusivity equation in 2D radial flow to approximate the transient pressure in the reservoirs. Fluid and rock compressibilities are taken into consideration, which allow calculating the breakthrough time and the leakage rate of CO2 to the overburden accurately. We use numerical simulations to verify the proposed time-dependent semi-analytical solution. The results show good agreement in both pressure and leakage rates. Sensitivity analysis is then conducted to assess different CO2 leakage scenarios to the overburden. The developed semi-analytical solution provides a new simple and practical approach to assess the potential of CO2 leakage outside the storage site. This approach is an alternative to numerical methods when detailed simulations are not feasible. Furthermore, the proposed solution can also be used to verify numerical codes, which often exhibit numerical artifacts. [ABSTRACT FROM AUTHOR]

The carbon dioxide emission from the industrial sector and the power plant contribute significantly to global climate change for several decades. The carbon capture and storage technology is the primary solution to reach the reduction target of carbon dioxide emissions. The carbon capture and storage activities involve CO 2 capturing, transporting, and storing in geological storage, requires number planning. The process integration approach by pinch analysis method can be used for the carbon capture and storage planning problem and to develop the carbon capture and storage network design. However, the applicability of the method needs to be evaluated when some constraints in carbon capture and storage network design are applied. This paper proposes an improved pinch analysis based method for carbon capture and storage target and network design. The method begins with targeting the maximum carbon exchange in the carbon capture and storage system, which is followed by designing the carbon capture and storage network. Next, the capital-carbon trade-off is introduced as a new strategy for assessing carbon capture and storage network design to show the economic feasibility of the design. Four case studies demonstrate the applicability of the proposed method to the carbon capture and storage systems in the central and western part of Indonesia. The application of this new strategy in the western part of Indonesia as a single region system revealed that the flat minimum of the total annual cost is obtained at a five year time difference with the amount of up to US$ 149.3 million. Image 1 • A CCS cascade analysis in central and western part of Indonesia was introduced. • A systematic approach in multi-region and multi- period was proposed. • Cascade analysis with minimum time difference was shown to be a good method. • Grid diagram showing the pairing between source and sink was a power tool. • Capital-carbon trade-off as a new strategy was proposed to assess CCS system design. [ABSTRACT FROM AUTHOR]

This paper presents an assessment of the cost performance of CO2 capture technologies when retrofitted to a cement plant: MEA-based absorption, oxyfuel, chilled ammonia-based absorption (Chilled Ammonia Process), membrane-assisted CO2 liquefaction, and calcium looping. While the technical basis for this study is presented in Part 1 of this paper series, this work presents a comprehensive techno-economic analysis of these CO2 capture technologies based on a capital and operating costs evaluation for retrofit in a cement plant. The cost of the cement plant product, clinker, is shown to increase with 49 to 92% compared to the cost of clinker without capture. The cost of CO2 avoided is between 42 €/tCO2 (for the oxyfuel-based capture process) and 84 €/tCO2 (for the membrane-based assisted liquefaction capture process), while the reference MEA-based absorption capture technology has a cost of 80 €/tCO2. Notably, the cost figures depend strongly on factors such as steam source, electricity mix, electricity price, fuel price and plant-specific characteristics. Hence, this confirms the conclusion of the technical evaluation in Part 1 that for final selection of CO2 capture technology at a specific plant, a plant-specific techno-economic evaluation should be performed, also considering more practical considerations. [ABSTRACT FROM AUTHOR]

• Economics of advanced IGCC plants for flexible power and hydrogen production. • Plants employ gas switching combustion and membrane-assisted water–gas shift. • CO 2 avoidance costs €25/ton compared to €44/ton for pre-combustion capture. • When the flexibility benefit is accounted for, CO 2 avoidance costs are almost zero. • Flexible power & H 2 production improves annual investment returns by 6%-points. Variable renewable energy (VRE) has seen rapid growth in recent years. However, VRE deployment requires a fleet of dispatchable power plants to supply electricity during periods with limited wind and sunlight. These plants will operate at reduced utilization rates that pose serious economic challenges. To address this challenge, this paper presents the techno-economic assessment of flexible power and hydrogen production from integrated gasification combined cycles (IGCC) employing the gas switching combustion (GSC) technology for CO 2 capture and membrane assisted water gas shift (MAWGS) reactors for hydrogen production. Three GSC-MAWGS-IGCC plants are evaluated based on different gasification technologies: Shell, High Temperature Winkler, and GE. These advanced plants are compared to two benchmark IGCC plants, one without and one with CO 2 capture. All plants utilize state-of-the-art H-class gas turbines and hot gas clean-up for maximum efficiency. Under baseload operation, the GSC plants returned CO 2 avoidance costs in the range of 24.9–36.9 €/ton compared to 44.3 €/ton for the benchmark. However, the major advantage of these plants is evident in the more realistic mid-load scenario. Due to the ability to keep operating and sell hydrogen to the market during times of abundant wind and sun, the best GSC plants offer a 6–11%-point higher annual rate of return than the benchmark plant with CO 2 capture. This large economic advantage shows that the flexible GSC plants are a promising option for balancing VRE, provided a market for the generated clean hydrogen exists. [ABSTRACT FROM AUTHOR]

We describe an ongoing project concerned with the systematic development of environments that support the specification and design of concurrent systems. The project has two key aspects: an existing and working system, Clara, that supports Milner's CCS as a specification and design language; and the development of general techniques for computer-aided generation of Clara-like environments for other concurrent languages. In this paper, we focus on the Clara environment. The Clara environment has two main components: 1) support for the usage of formal techniques in the design process, and 2) a rich and highly interactive simulation facility. A further distinguishing feature is the environment's graphical user interface which is based on a pictorial version of CCS. CCS is one of the most promising formalisms for defining concurrent systems and has been used successfully in many practical applications. This makes an environment that supports the calculus attractive in its own right. Moreover, the semantics of CCS is defined nonprocedurally in two phases: an operational semantics given as a set of inference rules, and then an algebraic semantics represented by a set of equational rules; This nonprocedural representation of formal semantics constitutes the foundation of our strategy for exporting the functionalities of Clara to its "clone environments." [ABSTRACT FROM AUTHOR]

• The synthesis and applications of MOFs for CO 2 adsorption was reviewed. • Comparison among different synthesis routes. • The synthesis routes effects on the CO 2 adsorption capacity. • High CO 2 adsorption and selectivity found at ambient temperature. The environment sustenance and preservation of global climate are known as the crucial issues of the world today. Currently, the crisis of global warming due to CO 2 emission has turned into a paramount concern. To address such a concern, diverse CO 2 capture and sequestration techniques (CCS) have been introduced so far. In line with this, Metal Organic Frameworks (MOFs) have been considered as the newest and most promising material for CO 2 adsorption and separation. Due to their outstanding properties, this new class of porous materials a have exhibited a conspicuous potential for gas separation technologies especially for CO 2 storage and separation. Thus, the present review paper is aimed to discuss the adsorption properties of CO 2 on the MOFs based on the adsorption mechanisms and the design of the MOF structures. In addition, the main challenge associated with using this prominent porous material has been mentioned. [ABSTRACT FROM AUTHOR]

The study explores future development of biomass uses across different climate policy scenarios and under different assumptions of biomass supply availability and technology performances. Broad bioenergy technology portfolios and generations provide flexibility to allocate bioenergy to supply a specific final energy mix and to remove carbon dioxide by combining bioenergy with carbon capture and sequestration (BECCS). The paper aim is to perform a detailed and focused analysis of the availability of biomass gasification and methanisation and the role of these green gas energy carriers in the decarbonisation strategies using a model based approach to see how some countries technology appropriation evolves through the XXIst century. The results show that the future of bioenergy depends mostly on countries bioenergy supply and demand that are partly triggered by climate policies. Besides, very diverse local biomass end use patterns are highlighted depending on local resource availability, economic growth and climate policies. The majority of modern uses will be possible with a biomass transformation through the gas vector thanks to methanisation and gasification processes. Technology maturities and efficiencies are also essential for bioenergy development for the field competitiveness. In presence of climate policies, the deployment of biomass methanisation and gasification increases two or three times faster due to higher competitiveness compared to highly taxed fossil fuel. The possibility to implement CCS fosters even more the use of bioenergy for decarbonisation strategies in the long term and switching the allocation of the resource in favor of gasification with CCS. • Bioenergy potential is used from 25% in 2015 to 75–85% in 2100. • With climate policies, methanisation and gasification develop 2–3 times faster. • Biomass valorization plays a major role in electricity and fuels conversion. • Electricity and heat valorizations are prominent in North, biofuels elsewhere. • Methanisation develops earlier than gasification but it catches up after 2050. [ABSTRACT FROM AUTHOR]

The paper presents an analysis of the possible location of geological formations suitable for CO2 storage in the Upper Silesia Coal Basin, Poland. The range of the reservoir has been determined on the basis of an analysis of basic geological parameters, which determine the selection criteria for sites suitable for CO2 storage. A dynamic modelling of the CO2 distribution in the aquifer is presented. Based on the constructed model of migration, reactivity, and geochemical transport of CO2 in geological structures, it is possible to identify potential migration routes and escape sites of CO2 on the surface. The analysis of the technical and geological possibilities of CO2 storage was carried out according to the regulations of the complex Polish geological law, specifically in terms of sequestration possibilities in geological formations. [ABSTRACT FROM AUTHOR]

• Developed life cycle assessment model for biomass co-firing power plants with CCS. • Given detailed process-level input-output table based on mass and energy balances. • Co-firing of 25% biomass with coal can achieve near-zero emissions in CCS plants. • Environmental burden shifts significantly as the co-firing ratio. • Uncertainty analysis was carried out for the environmental burden shift. As a carbon-neutral renewable energy source, biomass co-firing with coal contributes to reducing the carbon intensity of pulverized coal power plants with CO 2 capture and storage; thus, this process significantly reduces the greenhouse gas emissions of the power industry. However, various types of environmental impacts caused by co-firing have hindered the large-scale deployment of this technology. In this study, ten life cycle assessment models were developed based on the Integrated Environmental Control Model and GaBi software to quantify the performance parameters of different power plants and the influence of the co-firing ratio on various environmental impact categories. The system boundaries included raw material acquisition, raw material transport, energy conversion of power plants, CCS and brine treatment. The results indicated that a pulverized biomass/coal co-firing power plant with CCS can achieve near-zero emissions at a co-firing ratio of 25% and negative emissions of 877 kg CO 2 -e/MWh from a life-cycle perspective when coal is totally replaced. Co-firing biomass and coal in power plants has a passive impact on seven environmental categories, such as the eutrophication potential and toxicity potential, rather than on the global warming potential, abiotic resource depletion potential and acidification potential. The major causes of environmental burden shifting are energy penalties and indirect emissions from high-energy-consumption processes, especially emissions of N 2 O, NH 3 and ethylene oxide released during biomass extraction and solvent preparation. The conclusions and recommendations presented in this paper may have implications for deep decarbonization in other industrial sectors. [ABSTRACT FROM AUTHOR]

It is likely that the future availability of energy from fossil fuels, such as natural gas, will be influenced by how efficiently the associated CO2 emissions can be mitigated using carbon capture and sequestration (CCS). In turn, understanding how CCS affects the efficient recovery of energy from fossil fuel reserves in different parts of the world requires data on how the performance of each part of a particular CCS scheme is affected by both technology specific parameters and location specific parameters, such as ambient temperature. This paper presents a study into how the energy consumption of an important element of all CCS schemes, the CO2 compression process, varies with compressor design, CO2 pipeline pressure, and cooling temperature. Post-combustion, pre-combustion, and oxyfuel capture scenarios are each considered. A range of optimization algorithms are used to ensure a consistent approach to optimization. The results show that energy consumption is minimized by compressor designs with multiple impellers per stage and carefully optimized stage pressure ratios. The results also form a performance map illustrating the energy consumption for CO2 compression processes that can be used in further study work and, in particular, CCS system models developed to study performance variation with ambient temperature. [ABSTRACT FROM AUTHOR]