For deep-sea oil exploitation far away from land, there is inevitably the generation of oilfield-associated gas. It is a new method for recover oilfield associated gas by using a high-gravity device to generate hydrate. In this paper, the methane hydrate formation process of different packings in the high-gravity machine was studied. By comparing the structural morphology of varying packings and the characteristics of the hydrate in the high-gravity machine, a new type of layered packing is designed and manufactured. The volumetric storage capacity, normalized gas consumption rates and methane absorption time of foam metal packing, metal mesh packing, 3D printing spiral packing, and new layered packing were investigated experimentally. The results show that the new layered packing has significant advantages. The maximum volumetric storage capacity, normalized gas consumption rate, and the shortest methane absorption time are 239265 mol/(m³·min), and 74 min, respectively. It exhibits an excellent methane hydrate formation effect and the advantage of small equipment size. It is very suitable for the recovery of oilfield-associated gas produced in the process of offshore oil exploitation.

Transit-Oriented Development (TOD) has emerged as a critical strategy for advancing the green transformation of China's low-carbon cities. Conducting carbon footprint research on TOD from a whole life cycle perspective holds profound significance for achieving the Dual Carbon Goals. This study constructs five carbon footprint calculation models based on life cycle assessment theory. Setting four residential travel scenario assumptions thoroughly examines the whole life cycle carbon emissions of China SH TOD project and the carbon reduction achieved through transportation during the operation phase. Results indicate that total carbon emissions in the study area amount to 2.9902 million tons. Considering solely the carbon reduction effect from shifts in resident travel modes under the TOD model, the total carbon reduction reaches 203600 tons, with a carbon reduction effectiveness evaluation index of 6.81%. Compared to the continuous increase in carbon footprint observed after the operation of traditional residential and commercial projects, the carbon reduction effect is notably significant. Furthermore, the study identified key high-emission stages within the lifecycle through model-based calculations and proposed targeted mitigation strategies. These findings provide recommendations for energy conservation, carbon reduction, and sustainable development in TOD projects.

Bioethanol plays a crucial role in the global transition to sustainability, serving as a renewable fuel especially in the transportation sector, and a versatile renewable chemical precursor in industries, mitigating greenhouse gas (GHG) emissions. Although bioethanol is renewable, its production is still carbon-intensive, with most emissions arising from fermentation and cogeneration. Despite significant advancements, existing works on bioethanol have largely focused on individual decarbonization elements (e.g., CCU, CCS in bioenergy, and process intensification in ethanol production). Few studies link these strategies together to show how they could collectively move bioethanol toward carbon-negative production. This review aims to fill that gap by systematically analyzing the evolution of bioethanol production processes, identifying key sources of CO₂ emissions, and critically evaluating state-of-the-art strategies—including process optimization, CCU, and CCS—within a unified framework. Overall, this review underscores that integrating process optimization, CCU, and CCS can transform bioethanol production from a low-carbon fuel into a negative-emission technology, reinforcing its pivotal role in global decarbonization efforts.

The high carbon emissions associated with the cement industry underscore the urgent need for low-carbon alternative materials. Compared with other alternatives, Reactive Magnesia Cement (RMC) offers the potential to absorb CO₂. However, current research on RMC remains fragmented, lacking a systematic overview of its complete processing route. This review summarizes the carbonation mechanism of RMC and provides a comprehensive discussion of evaluation methods for its carbonation degree. In addition, the review provides an in-depth analysis of factors influencing carbonation and strategies to enhance it. Specifically, we categorize the mechanisms and evaluate the effectiveness of various methods, with an emphasis on environmentally friendly production processes to identify the most optimal approaches. Finally, the study highlights the carbon footprint of RMC and discusses the challenges associated with achieving low-carbon RMC production.

Vanadium redox flow batteries (VRFBs) have held significant promise in large-scale energy storage applications due to their advantages, including long cycle life, high safety, and the ability to independently design power and capacity. However, the relatively low power density has remained a critical bottleneck for further development. As a key material in VRFB power units, enhancing the performance of graphite felt electrodes has represented an effective strategy for achieving high-power battery technology. To improve the activity of graphite felt electrodes, this study has employed an experimental verification approach to investigate battery performance parameters under various activation temperatures and durations, thereby identifying the optimal activation conditions. In contrast to prior studies that exclusively targeted 400°C without systematically optimizing activation duration, this study has systematically evaluated five activation temperatures and four activation durations to clarify the synergistic influence of these parameters on VRFB performance. Specifically, experiments have been conducted at room temperature using activation temperatures of 300, 350, 400, 450, and 500°C, as well as activation durations of 24, 11, 7, and 3 h. The results have indicated that an activation temperature of 400°C yielded notable improvements in charge/discharge performance, internal resistance, efficiency, and capacity retention. Notably, energy efficiency has increased by 5.06%, 5.94%, 3.67%, and 4.72% under these conditions. This study has identified the optimal activation conditions of “400°C for 7 h” and has provided the corresponding performance data, which can help reduce research costs associated with electrode activation in future investigations. This study has provided valuable insights into electrode activation and has offered guidance for enhancing VRFB performance.