Reducing the carbon footprint of cement industry by post-combustion CO2 capture: Techno-economic and environmental assessment of a CCS project in Romania

Roadmap to a net-zero carbon cement sector: Strategies, innovations and policy imperatives

The cement industry plays a significant role in global carbon emissions, underscoring the urgent need for measures to transition it toward a net-zero carbon footprint. This paper presents a detailed plan to this end, examining the current state of the cement sector, its carbon output, and the imperative for emission reduction. It delves into various low-CO2 technologies and emerging innovations such as alkali-activated cements, calcium looping, electrification, and bio-inspired materials. Economic and policy factors, including cost assessments and governmental regulations, are considered alongside challenges and potential solutions. Concluding with future prospects, the paper offers recommendations for policymakers, industry players, and researchers, highlighting the roadmap's critical role in achieving a carbon-neutral cement sector.

Decarbonization of Power and Industrial Sectors: The Role of Membrane Processes

Carbon dioxide (CO₂) is the single largest contributor to climate change due to its increased emissions since global industrialization began. Carbon Capture, Storage, and Utilization (CCSU) is regarded as a promising strategy to mitigate climate change, reducing the atmospheric concentration of CO₂ from power and industrial activities. Post-combustion carbon capture (PCC) is necessary to implement CCSU into existing facilities without changing the combustion block. In this study, the recent research on various PCC technologies is discussed, along with the membrane technology for PCC, emphasizing the different types of membranes and their gas separation performances. Additionally, an overall comparison of membrane separation technology with respect to other PCC methods is implemented based on six different key parameters-CO₂ purity and recovery, technological maturity, scalability, environmental concerns, and capital and operational expenditures. In general, membrane separation is found to be the most competitive technique in conventional absorption as long as the highly-performed membrane materials and the technology itself reach the full commercialization stage. Recent updates on the main characteristics of different flue gas streams and the Technology Readiness Levels (TRL) of each PCC technology are also provided with a brief discussion of their latest progresses.

Environmental impact assessment of post-combustion CO2 capture technologies applied to cement production plants

Decarbonizing the cement manufacturing sector presents an interesting and pressing challenge as it is one of the largest energy consumers in industry (i.e., 7%), emitting considerable amounts of anthropogenic carbon dioxide (i.e., 7%). This paper performs a technical and environmental assessment of decarbonisation of cement production through process modelling and simulation, thermal integration analysis, and Life Cycle Assessment (LCA). Integration of three post-combustion capture methods for a conventional cement plant with an annual productivity of one million tons and a carbon capture rate of 90% is evaluated in comparison to the reference case without carbon capture and storage (CCS). Mass and energy balances derived from simulations are used for the assessment of three innovative capture systems: reactive gas-liquid absorption using Methyl-Di-Ethanol-Amine, reactive gas-solid adsorption using calcium looping (CaL) technology and membrane separation. For the LCA study, a "cradle-to-gate" approach is carried out using GaBi software, according to the ReCiPe impact assessment method. The general conclusion is that integrating the CCS methods into the cement production process leads to a decrease in global warming potential (GWP) in the range of 69.91%-76.74%. Of the CCS technologies analysed, CaL technically outperforms the others as it requires 34% less coal and provides 1.6 times higher gross energy efficiency. From an environmental perspective, CaL integration ranks first, with the lowest scores in six of the nine impact categories and a GWP reduction of 76.74% compared to the baseline scenario without CCS.

Life cycle assessment of combustion-based electricity generation technologies integrated with carbon capture and storage: A review

Carbon capture and storage (CCS) is the key technology to reduce CO₂ emissions from the conventional power systems. CCS has the flexibility, compatibility, and great potential to reduce emissions when combined with the current energy infrastructure. Through quantifying the environmental benefits of the combustion-based electricity generation system with CCS by life cycle assessment (LCA), decision-makers can grasp the contribution of upstream and downstream processes to various environmental impacts, a better trade-off between climate change and non-climate impact categories. This work reviews the LCA research on the combustion-based electricity generation system integrated with CCS in the past 10 years. These studies show that CCS can reduce the direct CO₂ emissions from power plants by nearly 90%. While CCS effectively mitigates climate change, it also increases other environmental impacts to varying degrees and results in energy penalty of 15-44%. The actual greenhouse gas of the power plant is reduced by 40-80%. We further analyze a series of key issues involved in the LCA of the combustion-based electricity generation system integrated with CCS, including the functional unit, basic assumptions, system boundaries and assessment methods. Time span and the leakage need to be considered by researchers in LCA. The perspective of research needs to shift from the specific application of a single CCS to the impact assessment of large-scale deployment, and a single environment or economic discipline to interdisciplinary assessment. It is more cost-effective to realize the coordinated emission reduction between the power plant and the upstream and downstream supply chain.

From Unavoidable CO2 Source to CO2 Sink? A Cement Industry Based on CO2 Mineralization

The cement industry emits 7% of the global anthropogenic greenhouse gas (GHG) emissions. Reducing the GHG emissions of the cement industry is challenging since cement production stoichiometrically generates CO₂ during calcination of limestone. In this work, we propose a pathway towards a carbon-neutral cement industry using CO₂ mineralization. CO₂ mineralization converts CO₂ into a thermodynamically stable solid and byproducts that can potentially substitute cement. Hence, CO₂ mineralization could reduce the carbon footprint of the cement industry via two mechanisms: (1) capturing and storing CO₂ from the flue gas of the cement plant, and (2) reducing clinker usage by substituting cement. However, CO₂ mineralization also generates GHG emissions due to the energy required for overcoming the slow reaction kinetics. We, therefore, analyze the carbon footprint of the combined CO₂ mineralization and cement production based on life cycle assessment. Our results show that combined CO₂ mineralization and cement production using today's energy mix could reduce the carbon footprint of the cement industry by 44% or even up to 85% considering the theoretical potential. Low-carbon energy or higher blending of mineralization products in cement could enable production of carbon-neutral blended cement. With direct air capture, the blended cement could even become carbon-negative. Thus, our results suggest that developing processes and products for combined CO₂ mineralization and cement production could transform the cement industry from an unavoidable CO₂ source to a CO₂ sink.

An integrated methodology to overcome barriers to climate change mitigation strategies: a case of the cement industry in India

Cement is a basic requirement of today's society and is the only thing that humans consume more volume than water, but cement manufacturing is the most energy- and emission-intensive process. Hence, the cement industry is currently under pressure to reduce greenhouse gases (GHGs) emissions. Climate change mitigation strategies implemented in the industry leads to GHGs reduction, climate risks, pollutants, and another adverse impact on the environment. In order to implement climate change mitigation strategies in the cement industry, a careful analysis of barriers that hinder the emission reduction must be taken. However, most existing research on the barriers to mitigation measures is focused on developed countries. Among the most important emerging economies, India, the second-largest producer and consumer of cement, faces challenges to implement emission reduction measures. To bridge this gap, this paper identifies and evaluates the barriers and solutions to overcome these barriers in the context of India. This study employs a three-phase methodology based on fuzzy analytical hierarchy process (AHP) and fuzzy technique for order performance by similarity to ideal solution (TOPSIS) to identify barriers and solutions to overcome these barriers to climate change mitigation strategies adoption in Indian cement industry. Fuzzy AHP is employed to prioritize these barriers, and to rank solutions of these barriers, Fuzzy TOPSIS is employed. Ten Indian cement manufacturing industry is taken to illustrate the proposed three-phase methodology. Finally, the result of the analysis offers an effective decision support tool to the Indian cement industry to eliminate and overcome barriers to mitigation strategies adoption and build their green image in the market.

Techno-Economic Assessment of Different Heat Exchangers for CO2 Capture

We examined the cost implications of selecting six different types of heat exchangers as the lean/rich heat exchanger in an amine-based CO2 capture process. The difference in total capital cost between different capture plant scenarios due to the different costs of the heat exchangers used as the lean/rich heat exchanger, in each case, is in millions of Euros. The gasketed-plate heat exchanger (G-PHE) saves significant space, and it saves considerable costs. Selecting the G-PHE instead of the shell and tube heat exchangers (STHXs) will save €33 million–€39 million in total capital cost (CAPEX), depending on the type of STHX. About €43 million and €2 million in total installed costs (CAPEX) can be saved if the G-PHE is selected instead of the finned double-pipe heat exchanger (FDP-HX) or welded-plate heat exchanger, respectively. The savings in total annual cost is also in millions of Euros/year. Capture costs of €5/tCO2–€6/tCO2 can be saved by replacing conventional STHXs with the G-PHE, and over €6/tCO2 in the case of the FDP-HX. This is significant, and it indicates the importance of clearly stating the exact type and not just the broad classification of heat exchanger used as lean/rich heat exchanger. This is required for cost estimates to be as accurate as possible and allow for appropriate comparisons with other studies. Therefore, the gasketed-plate heat exchanger is recommended to save substantial costs. The CO2 capture costs of all scenarios are most sensitive to the steam cost. The plate and frame heat exchangers (PHEs) scenario’s capture cost can decline from about €77/tCO2 to €59/tCO2 or rise to €95/tCO2.

The UK and German Low-Carbon Industry Transitions from a Sectoral Innovation and System Failures Perspective

Industrial processes are associated with high amounts of energy consumed and greenhouse gases emitted, stressing the urgent need for low-carbon sectoral transitions. This research reviews the energy-intensive iron and steel, cement and chemicals industries of Germany and the United Kingdom, two major emitting countries with significant activity, yet with different recent orientation. Our socio-technical analysis, based on the Sectoral Innovation Systems and the Systems Failure framework, aims to capture existing and potential drivers of or barriers to diffusion of sustainable industrial technologies and extract implications for policy. Results indicate that actor structures and inconsistent policies have limited low-carbon innovation. A critical factor for the successful decarbonisation of German industry lies in overcoming lobbying and resistance to technological innovation caused by strong networks. By contrast, a key to UK industrial decarbonisation is to drive innovation and investment in the context of an industry in decline and in light of Brexit-related uncertainty.

An integrated approach using AHP and DEMATEL for evaluating climate change mitigation strategies of the Indian cement manufacturing industry

Concrete, a cement-based product is the highest manufactured and second highest consumed product after water on earth. Across the world, production of cement is the most energy and emission intensive industry hence, the cement industry is currently under pressure to reduce greenhouse gases emissions (GHGEs). However, reducing the GHGEs of the cement industry especially for developing country like India is not an easy task. Cement manufacturing industry needs to focus on significant climate change mitigation strategies to reduce the GHGEs to sustain its production. This study aims at identifying significant climate change mitigation strategies of the cement manufacturing industry in the context of India. Extant literature review and expert opinion are used to identify climate change mitigation strategies of the cement manufacturing industry. In the present study, a model projects by applying both AHP and DEMATEL techniques to assess the climate change mitigation strategies of the cement industry. The AHP technique help in establishing the priorities of climate change mitigation strategies, while the DEMATEL technique forms the causal relationships among them. Through AHP, the results of this research demonstrate that Fuel emission reduction is on top most priority while the relative importance priority of the main remaining factors is Process emission reduction - Electric energy-related emission - Emission avoidance and reduction - Management mitigation measures. The findings also indicate that the main factors, Process emission reduction, and Fuel emission reduction are categorized in cause group factors, while the remaining factors, Electric energy-related emission, Emission avoidance and reduction and Management mitigation measures are in effect group factors. Present model will help supply chain analysts to develop both short-term and long-term decisive measures for effectively managing and reducing GHGEs.

Environmental Performance Analysis of Cement Production with CO2 Capture and Storage Technology in a Life-Cycle Perspective

Cement manufacturing is one of the most energy and CO2 intensive industries. With the growth of cement production, CO2 emissions are increasing rapidly too. Carbon capture and storage is the most feasible new technology option to reduce CO2 emissions in the cement industry. More research on environmental impacts is required to provide the theoretical basis for the implementation of carbon capture and storage in cement production. In this paper, GaBi software and scenario analysis were employed to quantitatively analyze and compare the environmental impacts of cement production with and without carbon capture and storage technology, from the perspective of a life-cycle assessment; aiming to promote sustainable development of the cement industry. Results of two carbon capture and storage scenarios show decreases in the impacts of global warming potential and some environmental impacts. However, other scenarios show a significant increase in other environmental impacts. In particular, post-combustion carbon capture technology can bring a more pronounced increase in toxicity potential. Therefore, effective measures must be taken into account to reduce the impact of toxicity when carbon capture and storage is employed in cement production. CO2 transport and storage account for only a small proportion of environmental impacts. For post-combustion carbon capture, most of the environmental impacts come from the unit of combined heat and power and carbon capture, with the background production of MonoEthanolAmine contributing significantly. In combined heat and power plants, natural gas is more advantageous than a 10% coal-saving, and thermal efficiency is a key parameter affecting the environmental impacts. Future research should focus on exploring cleaner and effective absorbents or seeking the alternative fuel in combined heat and power plants for post-combustion carbon capture. If the power industry is the first to deploy carbon capture and storage, oxy-combustion carbon capture is an excellent choice for the cement industry.