Advances in biogas valorization and utilization systems: A comprehensive review

Life-Cycle GHG Emissions of Cassava-Based Bioethanol Production

The systems of heat, gas and electricity supply in settlements of Ukraine today are an example of inefficient use of fuel and energy resources in the state. Substitution of the main fuel – natural gas – for the needs of heat sources, electricity by alternative provides an imaginary saving of local budgets in the conditions of decentralization of public administration (due to the difference between the prices of natural gas and other organic fuels). At the same time, these measures alone raise a number of other problems. Increasing environmental pollution is one of them. The legislative support, tariff policy, requirements of current regulations in the field of environmental safety, production and sale of heat and electricity to consumers are analysed. According to them, the replacement of natural gas with alternative fuels is considered. Estimated cost of energy received, emissions of pollutants and greenhouse gases into the atmosphere are calculated. Emission indices were obtained based on data on the physicochemical composition and consumption of each of the fuels, taking into account the characteristics of combustion processes and measures to reduce the emissions of a particular ingredient. A comparative analysis of the fuels has been performed in relation to the environmental impact of the combustion products and the cost of the fuels themselves. In rural areas, after converting agricultural waste and wood processing as secondary raw materials into quality biofuels, it is advisable to introduce the replacement of traditional natural gas with alternative fuels. In urban areas, due to the implementation of measures to improve the energy efficiency of existing buildings and structures, it is possible to reduce the consumption of traditional natural gas, and the savings can be directed to their thermal modernization. This will allow the most environmentally friendly natural gas to be left as the main organic fuel for district heating needs.

Life cycle assessment of sludge anaerobic digestion combined with land application treatment route: Greenhouse gas emission and reduction potential

Advances of macroalgae biomass for the third generation of bioethanol production

Metal-organic frameworks (MOFs)-based catalysts are a unique class of porous crystalline materials with exclusive structural features such as tunable pore size, high surface area, functionalizable organic linkers, structural flexibility, and metal centers. The unique characteristics have made MOFs-based catalysts a promising material for a vast array of promising applications. In the present chapter, we systematically focus on the current improvement of MOFs-based catalysts for the production of value-added fine chemicals via conversion of CO2. The recycling of CO2 via utilization as a substituent carbon to produce fine chemicals is a promising method to overwhelm the global warming concern and make sustainable progress. The transformation of CO2 to fine chemicals based on MOFs catalysts is similar to hitting two birds with one stone. The CO2 capture capability of MOFs-based catalysts significantly enhances the interior of MOFs, which can be planned to have specific heteroatoms, embedded metal sites, defects, other building unit interactions for their potential toward CO2 conversion. The recent progress of MOFs-based catalysts for CO2 capture, conversion, and mechanism are summarized.

Toward Carbon-Neutral Water Systems: Insights from Global Cities

Porphyrin-based Porp-Tz porous polymeric framework for the concurrent production of solar-fuel and value-added fine chemicals: an economic approach towards sustainability.

Global climate change caused by greenhouse gas emission is the fundamental challenge facing mankind. Biological carbon dioxide fixation has recently attracted much attention. The Calvin–Benson–Bassham (CBB) cycle is a major carbon fixation pathway in the biosphere, and it is the most intensively studied because of its prominence and key role in nature as the primary pathway for net CO2 fixation. It was recently shown that expressing the enzymes ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and phosphoribulokinase (PRK) in Escherichia coli, Saccharomyces cerevisiae, Methylobacterium extorquens, Kluyveromyces marxianus, and Pichia pastoris could achieve CO2 fixation for the production of value-added chemicals. In addition, expressing the synthetic CBB cycle allowed strains to grow autotrophically on CO2. Here, we review the current understanding of the CBB cycle for CO2 fixation, summarize research progress in the assembly of the CBB cycle in heterotrophic microorganisms or developing synthetic autotrophs, and present the strategies to enhance carbon fixation efficiency of the CBB cycle in heterotrophic microorganisms. Recent progress in such applications in reinforcing CO2 fixation for the improved production of various value-added chemicals is also summarized. The challenges encountered in this process and future prospects are further discussed.

The article presents a retrospective review of natural gas consumption and greenhouse gas emissions from its consumption. It is determined that greenhouse gas emissions in the country as a whole decreased from 1990 to 2019 by 62.4%, emissions from natural gas consumption – by 71.7%. The potential for energy saving from structural changes in the economy is determined at the level of 5.2 billion m3 and the technological potential for energy saving from the introduction of energy saving measures and replacement of natural gas with other fuels in heat generating plants, including measures implemented in household sector, at the level of 7.5 billion m3 in 2040. Using the method of forecasting long-term demand for energy resources developed at the Institute of General Energy, the forecast of natural gas demand in Ukraine until 2040 is developed for the conservative scenario of economic development taking into account structural changes and technological energy saving in the country and enlarged sections of the economy. Slight growth in natural gas demand is projected to reach 32.9 billion m3 in 2040. The forecast of greenhouse gas emissions only from the use of natural gas by consumer groups and by the country as a whole is calculated. According to the assumption of moderate economic growth and the implementation of energy-saving measures, it is expected to reduce greenhouse gas emissions from natural gas use in 2030 (compared to 2017) and gradually increase after 2030. Therefore, to reduce greenhouse gas emissions after 2030, it is necessary to implement measures and technologies for the decarbonization of the country's economy. To assess the capability of meeting the target already set in Ukraine's 2nd National Contribution to the Paris Agreement, it is necessary to determine projected emissions not only from the use of natural gas but also from the use of coal and petroleum products, and to estimate emissions from other sources, including leakages. Determining the estimation of greenhouse gas emissions from leakages is a separate task. The obtained results allow to determine the largest sources of greenhouse gas emissions from natural gas consumption in the country's economy and to focus further research on identifying ways to reduce emissions. Keywords: forecast, demand, natural gas, greenhouse gas emissions, energy saving potential, populatio

The carbon dioxide issue has recently become the focus of global attention because of the position of CO 2 as the primary greenhouse gas and the implication of its emissions on the problems of climate change and global warming. In the past decade, strategies have largely focused on the development of different technologies for CO 2 capture and storage (CCS). The idea is rather than treating CO 2 as a waste, it can be regarded as a low value raw chemical for the production of value-added fuels and chemicals, finding beneficial ways to “use” in addition to permanently storing the emitted CO 2 . However, due to high stability of CO 2 molecule, it is a great challenge to thermally decompose CO 2 . High temperatures (>3000 K) are required to get a reasonable CO 2 conversion, incurring a high energy cost.

Blue revolution for food security under carbon neutrality: A case from the water-saving and drought-resistance rice

西安市温室气体排放的动态分析及等级评估

Combining models to estimate the impacts of future climate scenarios on feed supply, greenhouse gas emissions and economic performance on dairy farms in Norway

There are two types of approaches for analyzing various aspects related to green-house gas (GHG) emissions, i.e., top-down and bottom-up approaches. Although the top-down approach focuses on macro-economic perspectives, the bottom-up approach is more suitable to investigate GHG emissions at an industry level utilizing domain-specific knowledge. For example, a bottom-up analysis requires a wide variety of data such as energy demands, conversion factors, and energy efficiency, which may be obtained by analyzing industrial process data. This study aims to provide a bottom-up approach for analyzing GHG emissions from shipbuilding processes in Korea. Reference energy system and energy balance for shipbuilding processes are derived for bottom-up modeling. Based on the midterm forecast on energy demands of the Korean shipbuilding industry, it is shown that the business-as-usual GHG emissions may be obtained. Relevant mitigation measures are then investigated to analyze their mitigation potentials for low-carbon ship production. 1. Introduction Global climate change has recently drawn an increasing attention due to its adverse effects on our environment. Since the inception of Kyoto Protocol to the United Nations Frame-work conventions on climate change, local and international experts have long called for more international cooperation in coping with global warming. The main idea of international cooperative efforts is to impose binding obligations for greenhouse gas (GHG) emissions on participating countries. Even though some countries have withdrawn their commitment and others have been reluctant to adopting definite targets for emission reduction, many countries have already established a designated national authority to manage their GHG emissions. Korea has also established a national authority called "GHG Inventory and Research Center (GIR)" in 2010. One of the most important roles of GIR is to manage the national GHG emission levels and set the abatement target of various sectors through an efficient and integrated management of GHG-related information. Recently, GIR has conducted a series of research projects to analyze GHG emissions of industrial sectors in cooperation with a group of experts. This study presents the results from the analysis of GHG emissions and mitigation potentials for the shipbuilding processes in Korea. It should be noted that the scope of this study is limited to constructions processes in a shipyard even though the shipbuilding industry may encompass a broader range of industrial sectors such as steel production and transport. Adopting Model for Energy Supply Strategy Alternatives and their General Environmental Impacts (MESSAGE) developed by International Institute for Applied Systems Analysis in 1980s (Messner 1997), a bottom-up mathematical programming model is generated to derive the business-as-usual (BAU) GHG emissions in the construction processes in a shipyard. Abatement potentials of several technical abatement measures are also analyzed to help shipbuilders effectively cope with the issue of climate change.

Carbon dioxide (CO2) is regarded as one of the arch villains in the long debate on global warming, or what has now been more correctly termed climate change, as it accounts for approximately 85 % of the total greenhouse gases that are emitted annually. The majority of sources are from the combustion of fossil fuels. With a growing global population and consequently a growing demand for energy, there has been extensive research on alternative fuels and energy sources, as well technologies for the combustion of fossil fuels. In order to mitigate the environmental effects of carbon dioxide, numerous strategies have been proposed which focus on limitation of emissions from sources, capture, and degradation. Carbon dioxide in theory could be a potential feedstock for the production of fuel, energy, and value-added chemicals. In effect, carbon dioxide could be turned from a villain to a hero, i.e. producing energy while reducing greenhouse gases. It is therefore important that researchers continue to look for practically feasible, inexpensive, environmentally friendly, and energy efficient technologies that can utilize CO2 by converting it into energy, liquid hydrocarbon fuels, and value-added chemicals. This review presents the current state of the art in this regard, with emphasis on technological improvements to make carbon dioxide a viable feedstock for energy and value-added chemical production.