Carbon and Water Footprint Evaluation of 120Wp Rural Household Photovoltaic System: Case Study

This study uses the Life Cycle Analysis (LCA) to evaluate the magnitude of the environmental impact, in terms of global warming potential, and water footprint throughout the 20 years of useful life of a rural electrical energy concession comprised of 120Wp Households photovoltaic systems (HPS) in the isolated communities of San Martin, in the Peruvian Amazon region. On the other hand, due to the particular conditions of the system (installation, operation, maintenance, monthly tariff collection), it is necessary to know its real impact and sustainability;not only through the aforementioned environmental impact indicators, but also by energy intensity values required by the system throughout its life cycle. Therefore, this paper used the Cumulative energy demand (CED) method to determine the amount of energy taken from natural resources for each process involved in the LCA and calculated with this, i.e., the Energy Payback Time (EPBT) of the whole system. Likewise, the HPS has been environmentally compared to other case studies and the Peruvian Energy Mix, revealing a lower impact in the latter case and results within the range for stand-alone systems. Besides, the HPS shows a strong relation between energy production and O&M condition. Additionally, this study allows a further promotion of the use of this type of system in isolated areas, as well as the diversification of electricity generation in Peru.

Carbon Footprint in Waste Sector of Hydropower Plant: A Case Study of Nam Theun 2 Hydropower Plant

While hydropower is generally considered a clean energy source, it is important to recognize that their waste can still contribute to greenhouse gas emissions (GHG). The purpose of this study is to assess the carbon footprint associated with the waste sector throughout the operational phase of the Nam Theun 2 hydropower plant in Laos. Understanding the environmental impact of the waste sector is crucial for ensuring the plant’s sustainability. This study utilizes the theoretical estimation method recommended in the 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, as well as the Requirements for Specification with guidance at the organization level for quantification and reporting of GHG emissions and removals. We emphasize the significance of implementing sustainable waste management practices to reduce GHG emissions and minimize the environmental impact of hydropower operations. By conducting a comprehensive analysis, this paper also provides insights into the environmental implications of waste management in hydropower plants and identifies strategies to mitigate the carbon footprint in the waste sector. The findings contribute to a better understanding of the environmental sustainability of hydropower plants and provide valuable guidance for policymakers, energy producers, and environmental practitioners involved in hydropower plant design and operation.

The potential impact of increased whole grain consumption among Chinese adults on reducing healthcare costs and carbon footprint

Excessive consumption of refined grains harms human health and ecosystem viability.Whole grains,as a healthy and sustainable alternative to refined grains,can benefit individual health by providing dietary fiber,B vitamins,and bioactive substances.Additionally,they aid in improving the environment due to their higher extraction rate and lower carbon emission during the processing stage.However,few studies have attempted to evaluate the economic and social benefits of increasing the amount of whole grain in grain intake.This paper estimates the potential savings in healthcare costs and reduced food carbon footprints(CFs)that could result from a shift toward whole grain consumption following the Chinese Dietary Guidelines(CDG).We investigate hypothetical scenarios where a certain proportion(5–100%)of Chinese adults could increase their whole grain intakes as proposed by CDG to meet the average shortfall of 30.2 g.In that case,the healthcare costs for associated diseases(e.g.,type2 diabetes mellitus(T2DM),cardiovascular disease(CVD),and colorectal cancer(CRC))are expected to reduce by a substantial amount,from USD 2.82 to 56.37 billion;the carbon emission levels are also projected to decrease by0.24–5.72 million tons.This study provides compelling evidence that advocating for the transition towards greater consumption of whole grain products could benefit individual health,the environment,and society,by reducing both healthcare costs and carbon emissions.

Research on the Index System of Old Neighborhood Renovation Based on Green Building Evaluation Standard

With the advancement of the transformation,the contradiction between the residents’demand for a better living environment and the convenience of living in the settlements comes to the fore.Effective identification,organic integration,timely adoption,and correct decision-making for the transformation of old neighborhoods are pressing issues in the transformation of old neighborhoods.Therefore,this paper takes the green building evaluation standards of various countries as the research basis and support for the construction of the transformation strategy of old neighborhoods.Through the collection and comparative analysis of the indicators of green building evaluation standards,the index system of transformation is formed,and it also provides a certain foundation for the subsequent related research.

Analysis of Safety Assessment and Testing of Heavy Traffic Vehicles on Old Bridges Without Data

This article presents a real-life project that aimed to evaluate the safety of traffic vehicles on old bridges without any prior data.The project involved various safety inspections,including conventional,static,and dynamic load inspections and safety assessments.After conducting these tests,it was concluded that the structure of the old bridge is relatively safe,with only a few bumps.The bridge could function normally following appropriate treatment.The analysis provides valuable insights into the assessment of the quality and safety of such bridges to ensure the safe driving of heavy vehicles.

Impact of livelihood diversification of rural households on their ecological footprint in agro-pastoral areas of northern China

Human-environment relationship is a focus of academic researches and an understanding of the rela- tionship is important for making effective policies and decisions. In this study, based on rural household survey data of Taibus Banner, Duolun county and Zhengxiangbai Banner in the Inner Mongolia autonomous region of China, we identified the impact of livelihood diversification on ecosystems in these agro-pastoral areas by using the ecological footprint theory and methodology together with the one-way analysis of variance （ANOVA） and correlation analysis methods. In 2011, the total ecological footprint of consumption （EFC） was 0.665 g hm2, and the total ecological footprint of production （EFP） was 2.045 g hm2, which was more than three times the EFC. The ecological footprint of arable land consumption （EFAC） accounted for a large proportion of the EFC, and the ecological footprint of grassland production （EFGP） occupied a large proportion of the EFP. Both the ecological footprint of grassland consumption （EFGC） and EFGP had a significant positive correlation with the income, indicating that income was mainly depended on livestock production and the households with higher incomes consumed more livestock prod- ucts. The full-time farming households （FTFHs） had the highest EFP, ecological footprint of arable land production （EFAP）, EFGP and EFGC, followed by the part-time farming households （PTFHs） and non-farming households （NFHs）, which indicated that part-time farming and non-farming employment reduced the occupancy and con- sumption of rural households on local ecosystems and natural resources to some extent. When farming households engaged in livestock rearing, both the EFAP and EFAC became smaller, while the EFP, EFC, EFGC and EFGP increased significantly. The differences in ecological footprints among different household groups should be taken into account when making ecosystem conservation policies. Encouraging the laborers who have the advantages of participating in non-farming employment to move out of the rural areas and increasing the diversification of liveli- hoods of rural households are important in reducing the environmental pressures and improving the welfare of households in the study area. Moreover, grassland should be utilized more effectively in the future.

Research on the feasibility of storage and estimation model of storage capacity of CO_(2)in fissures of coal mine old goaf

The concept of the carbon cycle in the old goaf of a coal mine based on CO_(2)utilization and storage was put forward adhering to the principle of low-carbon development,utilization of space resources in old goafs,and associated gas resources development.Firstly,the evolution characteristics of overburden fissures in the goaf of the case was studied using a two-dimensional physical similarity simulation test,the sealing performance of the caprocks after stabilization was analyzed,and the fissures were counted and classi-fied.Then,the process of gaseous CO_(2)injection in the connected fissure was simulated by Ansys Fluent software,and the migration law and distribution characteristics of CO_(2)under the condition of gaseous CO_(2)injection were analyzed.Finally,the estimation models of free CO_(2)storage capacity in the old goaf were constructed considering the proportion of connected fissure and the effectiveness of CO_(2)injection.The CO_(2)storage capacity in the old goaf of the case coal mine was estimated.The results showed that a caprock group of“hard-thickness low-permeability hard-thickness”was formed after the caprock-fissures system in the goaf of the case tended to be stable vertically.The connected fissure,occlude cracks,and micro-fractures in the goaf accounted for 85.5%,8.5%,and 6%of the total fissures,respectively.Gaseous CO_(2)first migrated to the bottom of the connected fissure after CO_(2)was injected into the goaf,then spread horizontally along the bottom of the connected fissure after reaching the bottom,and finally spread longitudinally after filling the bottom of the entire connected fissure.The theoretical and effective storage capacities of free CO_(2)at normal temperature and pressure in the old goaf of the case were 9757 and 7477 t,respectively.The effective storage capacity of free CO_(2)at normal temperature and pressure in the old goaf after all minefield mined was 193404 t.The research can provide some reference for the coal mining industry to help the goal of“carbon peaking and carbon neutrality”.

The potential of green manure to increase soil carbon sequestration and reduce the yield-scaled carbon footprint of rice production in southern China

Green manure(GM)has been used to support rice production in southern China for thousands of years.However,the effects of GM on soil carbon sequestration(CS)and the carbon footprint(CF)at a regional scale remain unclear.Therefore,we combined the datasets from long-term multisite experiments with a meta-analysis approach to quantify the potential of GM to increase the CS and reduce the CF of paddy soils in southern China.Compared with the fallow-rice practice,the GM-rice practice increased the soil C stock at a rate of 1.62 Mg CO_(2)-eq ha^(-1) yr^(-1) and reduced chemical N application by 40%with no loss in the rice yield.The total CF varied from 7.51 to 13.66 Mg CO_(2)-eq ha^(-1) yr^(-1) and was dominated by CH_(4) emissions(60.7-81.3%).GM decreased the indirect CF by 31.4%but increased the direct CH_(4) emissions by 19.6%.In the low and high CH_(4) emission scenarios,the CH_(4) emission factors of GM(EF_(gc))were 5.58 and 21.31%,respectively.The greater soil CS offset the increase in GM-derived CF in the low CH_(4) scenario,but it could not offset the CF increase in the high CH_(4) scenario.A trade-off analysis also showed that GM can simultaneously increase the CS and reduce the total CF of the rice production system when the EF_(gc) was less than 9.20%.The variation in EF_(gc) was mainly regulated by the GM application rates and water management patterns.Determining the appropriate GM application rate and drainage pattern warrant further investigation to optimize the potential of the GM-rice system to increase the CS and reduce the total CF in China.

An analysis of energy consumption and carbon footprints of cryptocurrencies and possible solutions

There is an urgent need to control global warming caused by humans to achieve a sustainable future.CO_(2) levels are rising steadily,and while countries worldwide are actively moving toward the sustainability goals proposed during the Paris Agreement in 2015,we are still a long way to go from achieving a sustainable mode of global operation.The increased popularity of cryptocurrencies since the introduction of Bitcoin in 2009 has been accompanied by an increasing trend in greenhouse gas emissions and high electrical energy consumption.Popular energy tracking studies(e.g.,Digiconomist and the Cambridge Bitcoin Energy Consumption Index(CBECI))have estimated energy consumption ranges from 29.96 TWh to 135.12 TWh and 26.41 TWh to 176.98 TWh,respectively for Bitcoin as of July 2021,which are equivalent to the energy consumption of countries such as Sweden and Thailand.The latest estimate by Digiconomist on carbon footprints shows a 64.18 MtCO_(2) emission by Bitcoin as of July 2021,close to the emissions by Greece and Oman.This review compiles estimates made by various studies from 2018 to 2021.We compare the energy consumption and carbon footprints of these cryptocurrencies with countries around the world and centralized transaction methods such as Visa.We identify the problems associated with cryptocurrencies and propose solutions that can help reduce their energy consumption and carbon footprints.Finally,we present case studies on cryptocurrency networks,namely,Ethereum 2.0 and Pi Network,with a discussion on how they can solve some of the challenges we have identified.

Structural Damage Identification System Suitable for Old Arch Bridge in Rural Regions: Random Forest Approach

A huge number of old arch bridges located in rural regions are at the peak of maintenance.The health monitoring technology of the long-span bridge is hardly applicable to the small-span bridge,owing to the absence of technical resources and sufficient funds in rural regions.There is an urgent need for an economical,fast,and accurate damage identification solution.The authors proposed a damage identification system of an old arch bridge implemented with amachine learning algorithm,which took the vehicle-induced response as the excitation.A damage index was defined based on wavelet packet theory,and a machine learning sample database collecting the denoised response was constructed.Through comparing three machine learning algorithms:Back-Propagation Neural Network(BPNN),Support Vector Machine(SVM),and Random Forest(R.F.),the R.F.damage identification model were found to have a better recognition ability.Finally,the Particle Swarm Optimization(PSO)algorithm was used to optimize the number of subtrees and split features of the R.F.model.The PSO optimized R.F.model was capable of the identification of different damage levels of old arch bridges with sensitive damage index.The proposed framework is practical and promising for the old bridge’s structural damage identification in rural regions.

Carbon, Water, Ecological Footprints, Energy and Nutritional Densities of Omnivore and Vegan Culinary Preparations

This study aimed to evaluate energy and nutritional densities, water, carbon and ecological footprints, cost, of omnivorous and vegan main courses served in a university restaurant in the city of Rio de Janeiro. A cross-sectional, analytical study was conducted with 40 main dish-type preparations, 20 of which are omnivorous and 20 vegans, served at lunch, to assess energy and nutritional densities, carbon, water and ecological footprints and cost of preparations. We propose a healthy and sustainable preparation index (HSPI) to evaluate from the list, the best preparation options considering the nutritional quality combined with the impact that the food causes on the environment. Preparations with the highest HSPI were considered the best options because they have a good relation between the nutritional profile and the environmental impact. Results: Regarding energy (ED), nutritional (ND) densities and water, carbon and ecological footprints, omnivorous preparations presented much higher values when compared to the vegan ones. The omnivorous preparations had the highest average cost (R$ 3.44). Regarding the HSPI, vegan preparations showed better rates than omnivorous preparations. Food services should promote healthy and sustainable choices by offering menus with low energy density preparations, high nutritional density, and low environmental impact, considering local realities and customer needs. Conclusion: This study was able to evaluate the best preparation options, considering the nutritional profile and the food impact on the environment, using health and sustainable indicators. Obtaining indicators of preparations regarding healthiness and sustainability, in practice, translates environmental aspects in menu planning, which contribute to changes in food consumption patterns in food services, in addition to contributing to the reduction of the environmental impact. In this way, they can be used as tools added to the menu planning process for the analysis of the environmental impact of menus, in addition to nutritional and qualitative aspects.

Can food security and low carbon be achieved simultaneously?——An empirical analysis of the mechanisms influencing the carbon footprint of potato and corn cultivation in irrigation areas

Irrigated agriculture has tripled since 1950,accounting for 20%of the global arable land and 40%of food production.Irrigated agriculture increases food security yet has controversial implications for global climate change.Most previous studies have calculated carbon emissions and their composition in irrigated areas using the engineering approach to life-cycle assessment.By combining life cycle assessment(LCA)-based carbon emissions accounting with econometric models such as multiple linear regression and structural equation modeling(SEM),we conducted an interdisciplinary study to identify the influencing factors and internal mechanisms of the carbon footprint(CFP)of smallholder crop cultivation on irrigation reform pilot areas.To this end,we investigated corn and potato production data in the 2019–2020 crop years for 852 plots of 345 rural households in six villages(two irrigation agriculture pilot villages and four surrounding villages as controls)in Southwest China.The crop CFP in the irrigation agriculture pilot areas was significantly lower than in non-reform areas.Irrigation reforms mainly impacted the crop CFP through four intermediary effects:the project(implementation of field irrigation channels),technology(improving adoption of new irrigation technologies),management(proper irrigation operation and maintenance),and yield effects.All effects inhibited the CFP,except for the project effect that promotes carbon emissions.Among them,yield increase has the greatest impact on reducing CFP,followed by management and technology effects.Furthermore,planting practices,individual characteristics,and plot quality significantly impacted the crop CFP.This study has policy implications for understanding the food security–climate nexus in the food production industry.

Fences and hydropower:Important but overlooked Human Footprint

Human activities have impacted 77%of the terrestrial ecosystems(excluding Antarctica),and the remaining areas are becoming increasingly endangered.Mapping spatiotemporal dynamics of Human Footprint has been used to evaluate the cumulative interference on terrestrial environments globally.However,fences and hydropower,two widespread and rapidly expanding infrastructures,have not been considered regarding Human Footprint,despite their complicated and extensive effects on ecosystem functioning and species survival.Previous work has proved that fences increase habitat fragmentation,disrupt migratory routes,inadvertently trap and kill wildlife,and hinder genetic exchange.Hydropower construction also caused habitat loss,fragmentation,and degradation.These impacts have received global concern,but fences around the world are difficult to be detected due to the limitations of current cartographic technologies.Furthermore,the effect of hydropower on the terrestrial environment has been underestimated,making the research on this topic at a global scale still in its infancy.Therefore,building an observation network of global fences and hydropower is a necessary step to move forward in the assessment of the impact of human activities on our planet,but also to better provide scientific support for policy-making regarding global biodiversity conservation,the identification of protected areas,and the prioritization of ecological restoration areas.

Chemical and physical studies of metallic alloy-based old Indian coins with LIBS coupled with multivariate analysis

The present work aims to demonstrate the capabilities of Laser-induced Breakdown Spectroscopy(LIBS)coupled with a multivariate technique for rapid quantification and classification of old Indian coins made of various alloys.Thirteen old Indian coins in different years of circulation,(1922–1986)were selected for the study.The concentrations were determined by Calibration free LIBS(CF-LIBS)method.The concentration of cuprum(Cu)is negligible,and aluminum(Al)is maximum in the first five coins,and vice-versa in the remaining eight coins.Two different multivariate methods,Principal Component Analysis(PCA)and Soft Independent Modelling of Class Analogy(SIMCA)have been used to classify and identify the coins.PCA classified all thirteen samples into four main alloy categories.The discernment of unknown samples to their probable class membership of alloy was performed using SIMCA.The surface hardness(Brinell hardness number)is linearly correlated with the plasma temperature and LIBS intensity ratios.The sample surface of the first and fifth coin belongs to Al-alloy,having the least surface hardness,and it became harder for Cu–Ni alloy,Ni-brass alloy,and bronze alloy.The hardness of the surface is more for bronze sample twelve.It is also observed that the plasma temperature increases monotonically with the Brinell hardness number.This analysis provides valuable information on fabrication methodology and explains large diversification in the elementary composition of old coins.

An Extended Fuzzy-DEMATEL System for Factor Analyses on Social Capital Selection in the Renovation of Old Residential Communities

China has been promoting the renovation of old residential communities vigorously.Due to the financial pressure of the government and the sustainability of the renovation of old residential communities,public-private partnerships(PPP)have already gained attention.The selection of social capital is key to improving the efficiency of the PPP model in renovating old residential communities.In order to determine the influencing factors of social capital selection in the renovation of old residential communities,this paper aims to find an effective approach and analyze these factors.In this paper,a fuzzy decision-making and trial evaluation laboratory(fuzzy-DEMATEL)technique is extended and amore suitable systemis developed for the selection of social capital using the existing group decisionmaking theory.In the first stage,grounded theory is used to extract the unabridged key influencing factors for social capital selection in the renovation of old residential communities.Secondly,by considering the impact of expert weights,the key influencing factors are identified.The interactions within these influencing factors are discussed and the credibility of the results is verified by sensitivity analysis.Finally,these key influencing factors are sorted by importance.Based on the results,the government should focus on a technical level,organizationalmanagement abilities,corporate reputation,credit status,etc.This study provides the government with a theoretical basis and a methodology for evaluating social capital selection.

Carbon footprints in minimally invasive surgery:Good patient outcomes,but costly for the environment

Advancements in technology and surgical training programs have increased the adaptability of minimally invasive surgery(MIS).Gastrointestinal MIS is superior to its open counterparts regarding post-operative morbidity and mortality.MIS has become the first-line surgical intervention for some types of gastrointestinal surgery,such as laparoscopic cholecystectomy and appendicectomy.Carbon dioxide(CO_(2))is the main gas used for insufflation in MIS.CO_(2)contributes 9%-26%of the greenhouse effect,resulting in global warming.The rise in global CO_(2)concentration since 2000 is about 20 ppm per decade,up to 10 times faster than any sustained rise in CO_(2)during the past 800000 years.Since 1970,there has been a steady yet worrying increase in average global temperature by 1.7℃ per century.A recent systematic review of the carbon footprint in MIS showed a range of 6-814 kg of CO_(2)emission per surgery,with higher CO_(2)emission following robotic compared to laparoscopic surgery.However,with superior benefits of MIS over open surgery,this poses an ethical dilemma to surgeons.A recent survey in the United Kingdom of 130 surgeons showed that the majority(94%)were concerned with climate change but felt that the lack of leadership was a barrier to improving environmental sustainability.Given the deleterious environmental effects of MIS,this study aims to summarize the trends of MIS and its carbon footprint,awareness and attitudes towards this issue,and efforts and challenges to ensuring environmental sustainability.

Improving the Use of Insecticide-Treated Nets among Children under Five Years Old in Benin, West Africa

Background: In Benin, malaria represents the first cause of consultation and hospitalization (48% for children under 5 years old) in health units. It also accounts for 23.1% of deaths recorded in health facilities (MoH, 2019). Between the two main components of vector control adopted by Benin government, the mass distribution campaigns of Insecticide-Treated Nets (ITNs) remained the only proven cost-effective way to rapidly achieve high and equitable coverage (WHO, 2017). After the fourth mass distribution campaign conducted in 2017, the Demographic and Health Survey (DHS) data indicated that the percentage of children who slept under an ITN has increased from 20% in 2006 to 70% in 2011-2012 and to 76% in 2017-2018 while the incidence of malaria (tested positive) is increasing rapidly among children under 5 years old, growing from 36.5% in 2009 to 28.8% in 2012 and then to 51.4% in 2019. This study aims to understand this contrast by identifying the origin of the increase in ITN use over time among children under five years old and the factors which determine this use. Methods: Data from the Demographic and Health Survey (DHS) conducted in Benin respectively in 2006 and in 20018 were used during the analysis, which covered 13,445 children under five years old from 2006 DHS and 12,255 children from 2017-2018 DHS. Firstly, the data were analyzed using decomposition method to highlight the origin of the increase of ITN use over time among children under five years old. Secondly, the chi-square test analysis estimated the association between ITN use and some characteristics (wealth index, maternal or caregiver education level and child age). Finally, the logistic regression model was used to identify the main factors, which influence the net use over the study period. Results: This study shows that the improvement of basic conditions is the main origin of behavior change in the use of ITNs among children under five years old. This improvement of the basic conditions consists of making ITNs available in households and informing household members about the benefits of ITN use. So, the free ITN distribution campaigns, routine distribution, awareness campaigns about the benefits of ITN use are the strategies, which increase the household capacities and knowledge, allowing household members to make their children sleep under net. The analysis also shows that region of residence, wealth index of household, household size, religion, and child age continue to determine the ITN use among children under age 5 years old and MNCP will integrate the factors in malaria prevention strategies in order to achieve universal use of ITNs. Conclusions: Although, sleeping under ITN behavior has indeed spread among children under 5 years old, policymakers and other stakeholders should design strategies to maintain and improve the current level of ITN use to reach the collective protection threshold (80% according to WHO). Therefore, to address the challenges of universal use of ITN, the study recommends expanding the routine distribution system to private sector health centers;discussing issues related to health service utilization (particularly ITN use) within a consultation framework at the communal level. In addition, collecting qualitative and quantitative data in the Oueme region will allow better understanding of all aspects of the ITN use gap among children under 5 years.

Transformation Design of Old Parks Based on Behavior Psychology: A Case Study of Hefei Xiaoyaojin Park

City park undertakes the function of urban core green island. Hefei Xiaoyaojin Park providesa leisure and entertainment place for Hefei citizens. Although it has been continuously transformed andupgraded, there are still many places to be improved. Through behavior observation and questionnaire,the usage and satisfaction evaluation of tourists in Xiaoyaojin Park were obtained, and the transformationdesign of Xiaoyaojin Park was analyzed from the perspective of behavior psychology by analyzing thebehavior of tourists in different zones of Xiaoyaojin. Based on the premise of exploring the behaviorof tourists in different spaces, a city park environment that meets the needs of tourists can be created bypromoting the cultural context of the Three Kingdoms, improving the plant landscape and infrastructureof the site, optimizing the spatial function, and exploring the park design and transformation strategy that ismore in line with the needs of people, in order to provide new ideas for the future landscape transformationof Xiaoyaojin park, and offer reference suggestions for the future transformation design of old city parks.

Landscape Upgrading and Transformation of Old Urban Parks from the Perspective of Place Attachment:A Case Study of Nanchang Bayi Park

On the basis of combing the relevant theories of place attachment, the planning framework of upgrading and reconstruction of old parks based on place attachment was put forward. Taking Nanchang Bayi Park as an example, the methods and key points of landscape improvement and transformation of old urban parks based on place attachment were explained to provide new ways and references for the renewal of old urban parks.

煤矿充填固碳理论基础与技术构想

在国家“双碳”目标背景下,如何减少煤炭行业的碳排放、实现碳封存已成为亟待解决的难题。煤炭行业作为高碳化石能源生产者和主体碳排放源提供者,在生产和消费过程中引发的大宗固废堆存、大型采空区形成和大量CO_(2)排放是制约煤炭可持续开发利用与绿色健康发展的瓶颈所在。为协同解决二氧化碳封存与矿山固废消纳问题,将大宗固废处置、固废高值化利用、CO_(2)封存、采空区利用有机结合,提出了二氧化碳充填的理念,从碳汇能力评估角度界定了二氧化碳充填的3种类型。具体开展工作包括:①分析了CO_(2)充填料浆输运过程和矿化反应过程涉及到的基础理论,给出了各个过程的数学方程以及碳封存量计算公式,指出了温度、湿度等因素对矿化反应机理、碳封存量和充填体强度的影响规律。②总结了现阶段CO_(2)矿化的工艺方法、主要碱性工业固废的CO_(2)封存能力和CO_(2)矿化强化措施。在此基础上提出了基于直接湿法矿化和间接矿化的2种CO_(2)充填材料制备工艺,满足矿井充填的流动性、凝固特性和强度要求。③针对CO_(2)充填过程中的CO_(2)物理封存问题,提出了窄条带式胶结充填和综采架后胶结充填2种技术路径,前者通过在弱充填条带中构筑多贯通孔隙的充填体CO_(2)物理封存,后者借助充填支架和链式自行充填挡板在长壁工作面采空区中间断构筑充填带,控制顶板垮落,形成CO_(2)物理化学封存空间。④为了评估CO_(2)充填的碳平衡效果,依据全生命周期法界定了CO_(2)充填中碳足迹及碳消纳的计算边界。然后,梳理了CO_(2)充填过程中的碳足迹及碳消纳,分别考虑了CO_(2)的来源、用量、损耗、转化等因素。给出了包括原料运输、充填料浆制备、井下注入与充填等过程中的碳足迹及碳消纳计算方法。研究成果有望降低CO_(2)封存的能耗及成本,对煤炭绿色开采及其可持续开发利用具有深远的意义。