scholarly journals Parameter Effects in the Preparation of Pyrolytic Carbon from Agroforestry Biomass Waste

2021 ◽  
Vol 261 ◽  
pp. 04002
Author(s):  
Yuxin Sun ◽  
Jiaying Xu ◽  
Meixuan He ◽  
Yixuan Tang ◽  
Leichang Cao
Keyword(s):  
Fossil Fuels ◽  
Biomass Conversion ◽  
Pyrolytic Carbon ◽  
Research Progress ◽  
Biomass Combustion ◽  
Biomass Pyrolysis ◽  
Technological Parameters ◽  
Biomass Waste ◽  
Advantages And Disadvantages ◽  
Energy Shortage

Traditional fossil fuels are being replaced by pyrolytic carbonization fuel from agricultural and forestry biomass to address the energy shortage crisis and the environmental pollution caused by the massive burning of fossil fuels in recent years. This paper introduces the research progress in the preparation of agriculture and forestry biomass pyrolysis carbonization molding fuel. The advantages and disadvantages of different biomass conversion technology are presented. The effects of different technological parameters on the preparation of pyrolytic carbon from agricultural and forestry biomass waste were reviewed. Agriculture and forestry biomass combustion characteristics and their regularity are analyzed.

scholarly journals Research Progress in Conversion of CO2 to Valuable Fuels

Molecules ◽  
2020 ◽  
Vol 25 (16) ◽  
pp. 3653 ◽  
Author(s):  
Luyi Xu ◽  
Yang Xiu ◽  
Fangyuan Liu ◽  
Yuwei Liang ◽  
Shengjie Wang
Keyword(s):  
Fossil Fuels ◽  
High Efficiency ◽  
Environmental Problems ◽  
Research Progress ◽  
Large Contribution ◽  
Enzymatic Reactions ◽  
Co2 Conversion ◽  
Advantages And Disadvantages ◽  
Oil And Natural Gas ◽  
Natural Photosynthesis

Rapid growth in the world’s economy depends on a significant increase in energy consumption. As is known, most of the present energy supply comes from coal, oil, and natural gas. The overreliance on fossil energy brings serious environmental problems in addition to the scarcity of energy. One of the most concerning environmental problems is the large contribution to global warming because of the massive discharge of CO2 in the burning of fossil fuels. Therefore, many efforts have been made to resolve such issues. Among them, the preparation of valuable fuels or chemicals from greenhouse gas (CO2) has attracted great attention because it has made a promising step toward simultaneously resolving the environment and energy problems. This article reviews the current progress in CO2 conversion via different strategies, including thermal catalysis, electrocatalysis, photocatalysis, and photoelectrocatalysis. Inspired by natural photosynthesis, light-capturing agents including macrocycles with conjugated structures similar to chlorophyll have attracted increasing attention. Using such macrocycles as photosensitizers, photocatalysis, photoelectrocatalysis, or coupling with enzymatic reactions were conducted to fulfill the conversion of CO2 with high efficiency and specificity. Recent progress in enzyme coupled to photocatalysis and enzyme coupled to photoelectrocatalysis were specially reviewed in this review. Additionally, the characteristics, advantages, and disadvantages of different conversion methods were also presented. We wish to provide certain constructive ideas for new investigators and deep insights into the research of CO2 conversion.

Recent Patents on Valve Mechanism Device

2020 ◽  
Vol 13 (3) ◽  
pp. 230-241
Author(s):  
Ye Dai ◽  
Hui-Bing Zhang ◽  
Yun-Shan Qi
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Flow Direction ◽  
Research Progress ◽  
Valve Mechanism ◽  
Advantages And Disadvantages ◽  
Valve Structure ◽  
Valve Leakage ◽  
Safety And Reliability

Background: Valves are an important part of nuclear power plants and are the control equipment used in nuclear power plants. It can change the cross-section of the passage and the flow direction of the medium and has the functions of diversion, cutoff, overflow, and the like. Due to the earthquake, the valve leaks, which will cause a major nuclear accident, endangering people's lives and safety. Objective: The purpose of this study is to synthesize the existing valve devices, summarize and analyze the advantages and disadvantages of various devices from many literatures and patents, and solve some problems of existing valves. Methods: This article summarizes various patents of nuclear-grade valve devices and recent research progress. From the valve structure device, transmission device, a detection device, and finally to the valve test, the advantages and disadvantages of the valve are comprehensively analyzed. Results: By summarizing the characteristics of a large number of valve devices, and analyzing some problems existing in the valves, the outlook for the research and design of nuclear power valves was made, and the planning of the national nuclear power strategic goals and energy security were planned. Conclusion: Valve damage can cause serious safety accidents. The most common is valve leakage. Therefore, the safety and reliability of valves must be taken seriously. By improving the transmission of the valve, the problems of complicated valve structure and high cost are solved.

scholarly journals Bio-Derived Catalysts: A Current Trend of Catalysts Used in Biodiesel Production

Catalysts ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 812
Author(s):  
Hoang Chinh Nguyen ◽  
My-Linh Nguyen ◽  
Chia-Hung Su ◽  
Hwai Chyuan Ong ◽  
Horng-Yi Juan ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Fossil Fuels ◽  
Current Trend ◽  
Biodiesel Production ◽  
High Catalytic Activity ◽  
Promising Alternative ◽  
Advantages And Disadvantages ◽  
Biodiesel Synthesis ◽  
Alkali Catalysts ◽  
A Current

Biodiesel is a promising alternative to fossil fuels and mainly produced from oils/fat through the (trans)esterification process. To enhance the reaction efficiency and simplify the production process, various catalysts have been introduced for biodiesel synthesis. Recently, the use of bio-derived catalysts has attracted more interest due to their high catalytic activity and ecofriendly properties. These catalysts include alkali catalysts, acid catalysts, and enzymes (biocatalysts), which are (bio)synthesized from various natural sources. This review summarizes the latest findings on these bio-derived catalysts, as well as their source and catalytic activity. The advantages and disadvantages of these catalysts are also discussed. These bio-based catalysts show a promising future and can be further used as a renewable catalyst for sustainable biodiesel production.

scholarly journals Conversion of biomass to biofuels and life cycle assessment: a review

2021 ◽  
Author(s):  
Ahmed I. Osman ◽  
Neha Mehta ◽  
Ahmed M. Elgarahy ◽  
Amer Al-Hinai ◽  
Ala’a H. Al-Muhtaseb ◽  
...  
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Energy Demand ◽  
Fossil Fuels ◽  
Biomass Conversion ◽  
Biofuel Production ◽  
Process Efficiency ◽  
Liquid Fuels ◽  
Thermochemical Processes ◽  
Lower Temperature

AbstractThe global energy demand is projected to rise by almost 28% by 2040 compared to current levels. Biomass is a promising energy source for producing either solid or liquid fuels. Biofuels are alternatives to fossil fuels to reduce anthropogenic greenhouse gas emissions. Nonetheless, policy decisions for biofuels should be based on evidence that biofuels are produced in a sustainable manner. To this end, life cycle assessment (LCA) provides information on environmental impacts associated with biofuel production chains. Here, we review advances in biomass conversion to biofuels and their environmental impact by life cycle assessment. Processes are gasification, combustion, pyrolysis, enzymatic hydrolysis routes and fermentation. Thermochemical processes are classified into low temperature, below 300 °C, and high temperature, higher than 300 °C, i.e. gasification, combustion and pyrolysis. Pyrolysis is promising because it operates at a relatively lower temperature of up to 500 °C, compared to gasification, which operates at 800–1300 °C. We focus on 1) the drawbacks and advantages of the thermochemical and biochemical conversion routes of biomass into various fuels and the possibility of integrating these routes for better process efficiency; 2) methodological approaches and key findings from 40 LCA studies on biomass to biofuel conversion pathways published from 2019 to 2021; and 3) bibliometric trends and knowledge gaps in biomass conversion into biofuels using thermochemical and biochemical routes. The integration of hydrothermal and biochemical routes is promising for the circular economy.

Wet compounding with pyrolytic carbon black from waste tyre for manufacture of new tyre – A mini review

2021 ◽  
pp. 0734242X2110047
Author(s):  
Junqing Xu ◽  
Jiaxue Yu ◽  
Wenzhi He ◽  
Juwen Huang ◽  
Junshi Xu ◽  
...  
Keyword(s):  
Carbon Black ◽  
Pyrolytic Carbon ◽  
Research Progress ◽  
Rubber Matrix ◽  
Innovative Technology ◽  
Nano Materials ◽  
Natural Rubber Composites ◽  
Waste Tyres ◽  
Dry Mixing ◽  
Waste Tyre

Pyrolysis offers a more focused alternative to waste tyres treatment. Pyrolytic carbon black (CBp), the main product of waste tyre pyrolysis, and its modified species can be applied to tyre manufacturing realizing its high-value utilization. Modified pyrolytic carbon black/natural rubber composites prepared by a wet compounding (WC) and latex mixing process have become an innovative technology route for waste tyre remanufacturing. The main properties and applications of CBp reported in recent years are reviewed, and the main difficulties affecting its participation in tyre recycling are pointed out. The research progress of using WC technology to replace dry mixing manufacturing of new tyres is summarized. Through literature data and comparative studies, this paper points out that the characteristic of high ash content can be well utilized if CBp is applied to tyre manufacturing. This mini-review proposes a new method for high-value utilization of CBp. The composite mixing of CBp and carbon nano-materials under wet conditions is conducive to the realization of their good dispersion in the rubber matrix. This provides a new idea for customer resource integration and connection of industry development between the tyre production industry and waste tyre disposal management.

Analysis of Advanced Research Methods of Cement-Based Materials

2014 ◽  
Vol 633 ◽  
pp. 494-497
Author(s):  
Yan Zheng ◽  
Su Ping Cui ◽  
Ya Li Wang ◽  
Zi Ming Wang ◽  
Qian Jin Mao
Keyword(s):  
Research Methods ◽  
Research Progress ◽  
Microstructural Development ◽  
Resonance Spectroscopy ◽  
Complex Phenomenon ◽  
Advantages And Disadvantages ◽  
Testing Method ◽  
Cement Based Materials ◽  
Microscopy Techniques ◽  
Application Prospects

The hydration of cement is known to be a complex phenomenon. Although the broad pattern of reactions and microstructural development are known, a number of important questions remain unanswered. How to select the proper techniques is what the research people think of for now. This paper reviewed the domestic and international research progress and presented the advantages and disadvantages of these methods and the application prospects. Nuclear magnetic resonance spectroscopy (NMR), nanoindentation and electron microscopy techniques of cements were expounded in detail. Furthermore, through analyzing the results obtained by different research methods, the paper predicted the development prospect of advanced testing method of cement-based materials.

Weldability and machinability of the dissimilar joints of Ti alloy and stainless steel – A review

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Yan Zhang ◽  
YuanBo Bi ◽  
JianPing Zhou ◽  
DaQian Sun ◽  
HongMei Li
Keyword(s):  
Residual Stress ◽  
Stainless Steel ◽  
Bonding Temperature ◽  
Fusion Welding ◽  
Research Progress ◽  
Diffusion Welding ◽  
Ti Alloy ◽  
Dissimilar Joints ◽  
Advantages And Disadvantages ◽  
Fe Intermetallics

Abstract As two important industrial manufacturing materials, titanium alloys and stainless steel have their own advantages and disadvantages in terms of physical, chemical, and mechanical properties. The field of materials manufacturing has witnessed efforts to develop technical processes that can properly combine these two alloy types, aiming to effectively use their respective advantages. The welding technology for Ti alloy and stainless steel, as a research topic with broad prospects, is comprehensively and deeply analyzed in this review. The current research progress in this field was analyzed from different process perspectives such as fusion welding, brazing, diffusion welding, friction welding, explosive welding and vacuum hot-rolling welding. The results of the review showed that the greatest challenges of fusion welding are low ductility of the material, high residual stress, high cooling rate, and the formation of numerous brittle Ti-Fe intermetallics. By using appropriate intermediate materials between these two materials, the residual stress and brittle intermetallics near the interface of the transition joint can be minimised by solving the thermal expansion mismatch, reducing the bonding temperature and pressure, and suppressing the diffusion of elements such as Ti and Fe.

Recent Progress on Controlled Dielectrophoretic Assembly of Carbon Nanotubes

2012 ◽  
Vol 531-532 ◽  
pp. 485-489
Author(s):  
Chao Ding ◽  
Li Bao An ◽  
Xiao Xia Yang ◽  
Yan Yan Liu
Keyword(s):  
Carbon Nanotubes ◽  
Impedance Measurement ◽  
Research Progress ◽  
Mechanical And Thermal Properties ◽  
Single Electron Transistors ◽  
Advantages And Disadvantages ◽  
Field Emission Displays ◽  
Impedance Monitoring ◽  
Time Gap ◽  
Functional Components

Carbon nanotubes (CNTs) have drawn extensive research interest for a variety of applications in single electron transistors, field emission displays, interconnects, sensors, energy storage, composites, and many others due to their excellent electrical, mechanical, and thermal properties. One requirement for many of these applications is the need to integrate CNTs into various devices or circuits as functional components and different manipulation methods have been developed. This paper addresses the assembly of CNTs by dielectrophoresis (DEP) and reviews recent research progress of controlled assembly of CNTs. Totally six approaches are introduced in which different techniques including impedance measurement, optical induced DEP, floating electrode DEP, self-limiting resistor, fluidic assisted deposition, and real-time gap impedance monitoring of DEP are respectively used to control the yield of the DEP process. The advantages and disadvantages of these methods are analysed. The purpose is to help automating the DEP process of CNTs and other one-dimensional nanomaterials by presenting these advanced control techniques.

scholarly journals ANALYSIS OF EXTERNAL ENGINEERING NETWORK METHODS

2020 ◽  
Vol 4 (157) ◽  
pp. 7-11
Author(s):  
V. Zhvan ◽  
V. Donenko ◽  
S. Kulish ◽  
A. Taran
Keyword(s):  
Physical And Mechanical Properties ◽  
Directional Drilling ◽  
Horizontal Directional Drilling ◽  
Technological Parameters ◽  
Optimal Method ◽  
Advantages And Disadvantages ◽  
Analytical Review ◽  
Conducting Research ◽  
The Cost ◽  
Selection Of

The article is devoted to the effective analysis of trench and trenchless pipeline laying technologies. In the course of the work, an analytical review of pipeline assembly was performed, the main technological parameters, the scope of each method, and their advantages and disadvantages were determined. List of considered pipeline laying methods: trenching, horizontal directional drilling, mechanical puncture, hydraulic puncture, microtunneling and punching. The article analyzes the classical trench method and the most widely used trenchless ones: horizontal directional drilling; mechanical puncture; hydraulic puncture; microtunneling; punching. Each of these methods has several advantages and disadvantages. The choice of the optimal method of laying the pipeline depends on many factors: the physical and mechanical properties of soils and hydrogeological conditions, the length and diameter of the pipeline, the presence of other communications, buildings and structures, as well as the budget that customers have. Work time is the last deciding factor. Based on the results of the analysis of pipeline laying technologies and expert survey of construction industry experts, the cost table of each method was compiled, outlining the main characteristics of the technology: length of pipeline, speed of work, scope, cost, and the advantages and disadvantages of each of the considered methods. The conclusions about the use of each of the pipeline laying methods were made. Each of the methods has its advantages and disadvantages, so to choose the method of work it is necessary to conduct a comprehensive assessment of technological parameters, cost, scope and timing of work. The cost of lay-ing the pipeline consists of the following factors: conducting research; selection of diameter and determination of pipeline length; choice of laying method and equipment necessary for the works; selection of equipment, shut-off and control equipment and other materials arranged on the pipeline; terms of performance of works. Taking into account these factors, an estimate is made, which determines the cost of installation of a particular pipeline. After the analysis, we can conclude that among the methods of trenchless laying of pipelines can be identi-fied horizontally directional drilling, it is this method of laying the pipeline will be appropriate to use for our region. The drilling technique allows to carry out pipelines under obstacles, to pull long segments of networks, to repair site damage. This method is universal and can be used in almost any environment. Keywords: trenches, horizontal directional drilling, mechanical puncture, hydraulic piercing, microtunnelling, punching, pipeline.

Sign in / Sign up

Export Citation Format

Share Document