A remining technology of underground coal gasification at Zhongliangshan Coal Mine

The field trail used a mixture of steam and air with various levels of oxygen en- richment.Steady conditions were achieved in the field trail which produced high quality hydrogen-enriched syngas.To understand and optimize the UCG process,a simplified heat and mass transfer model was presented,providing a predictive tool for temperature and the major constituents of the syngas production.The model is compared with the field trail measurements for air and two levels of oxygen enrichment,showing reasonable agreement for the channel temperature and product syngas concentration profile.

Off-design Characteristics of IGCC System Based on Two-stage Coal-slurry Gasification Technology

整体煤气化联合循环（integrated gasification combinedcycle,IGCC）机组在一定情况下处于非设计工况运行。为了研究IGCC系统变工况特性,采用ThermoFlex软件建立基于两段式水煤浆气化技术的200 MW级整体煤气化联合循环系统模型,主要考查燃气轮机负荷、整体空分系数Xas、大气温度、大气压力对系统性能的影响。研究结果表明,降低燃气轮机负荷或者提高大气温度系统效率均呈先升高而后降低的趋势。整体空分系数Xas增加,机组发电效率降低。大气压力对系统效率影响较小。上述条件下采用两段水煤浆气化技术,系统性能可以得到有效改善。研究结果可为采用两段式水煤浆气化技术的IGCC系统的设计、运行提供参考。

New Breakthroughs in China's Coal Gasification Technology

It is learned from the 2013 Summit Forum on Strategic Development of Coal-to-Natural Gas in China that the China Sedin Engineering Company,Ltd.has developed with independent intellectual property rights two experimental furnaces for pressurized gasification of crushed coal,5 m

Gasification of lignite from Polish coal mine to hydrogen-rich gas

The efforts of the world research activities involved in clean coal technologies development focus to a considerable extent on integrated hydrogen and power generation technologies based on coal gasification.As an alternative to combustion pro-cesses,gasification offers increased efficiency,lower negative environmental impact as well as wider application range of the main product—synthesis gas—in power generation and chemical syntheses.In order to select the most optimal lignite for the purpose of gasification,it is necessary to determine coal reactivity,the key parameter characterizing how fast the fuel reacts with the gasifying medium and controlling its process ability in thermochemical conversion to energy and/or energy carriers.This paper presents the experimental results of oxygen/steam gasification of lignite coal char in a fixed bed reactor under atmospheric pressure and at the temperature of 700,800 and 900℃;the samples come from an open pit lignite mine in the southwest of Poland.The effectiveness of the gasification process was tested in terms of the total gas and hydrogen yields,gas composition,carbon conversion rate and chars reactivity.

An analysis of new generation coal gasification projects

The global trends of increasing oil and gas costs have compelled coal possessing countries to start long term underground coal gasification （UCG） projects. These enhance national energy security and are among the cleanest, ecologically safest coal utilization technologies. This paper delineates the major characteristics of such technologies and analyzes technical solutions. Highlighting the desire to develop large scale industrial UCG plants, pilot level projects are presented using a new UCG method developed in Russia by Joint Stock Company Gazprom Promgaz. This method is distinct for its high controllability, stability, and energy efficiency. New, efficient technical solutions have been developed over the last 10-15 years and are patented in Russia. They guarantee controllability and stability of UCG gas produc- tion. Over one hundred iniection and gas production wells have been operated simultaneously.

Production of synthetic hydrocarbons from coal through its underground gasification

The problem of the high-level processing of coal into synthetic motor fuels assumes worldwide actual meaning nowadays. Thereat, it is important especially for countries and regions which possess extensive coal resources and are forced to be guided by the import of liquid and gas hydrocarbons. However, a greater emphasis is paid to the given issue in Russia-The development of the federal program for highlevel processing of coal into synthetic motor fuels was initiated. This article describes options of underground coal gasification (UCG) use for the generation of hydrocarbons from UCG gas in the process of the Fischer-Tropsch synthesis (FTS). The technical and economic analysis of the integrated UCG-FTS powerchemical factories has detected their investment attractiveness and practicability of experimental-industrial testing at coal deposits of the Russian Federation.

Semi-Industrial Test of Underground Coal Gasification In Well No.2 in Xinhe, Xuzhou

The necessity of underground coal gasification is explained. The condition,technology character,and process of the semi-industrial test of underground coal gasification in well No. 2 at Xinhe, Xuzhou,are introduced. The test results indicate that the technique of long tunnel,large sectiou,two stage underground coal gasification can obtain a large output of coal gas with a high heat value, making the working process stable. So the feasibility of the new techuology is verified. It can be concluded that there will have a good application prospect of the technique in China.

Clean coal technologies in Japan： A review

Coal is the primary fossil fuel most used in the world for the electricity generation, iron making, and cement/concrete and chemical production. However, utilization of coal also results in emissions of CO_2, SO_x, NO_x and other noxious compounds. The development of clean coal technology(CCT) is a main issue to maintain a clean environment. CCT in Japan is considered the highest level in the world. In this review, the developing CCTs in Japan including high efficiency combustion technologies, advanced gasification technologies, CO_2 recovery and utilization technologies, and flue gas cleaning technologies are introduced and discussed. It is expected to provide some new view-of-points for CCT development.

Technology Roadmap of IGCC Industry in China

With the increasing energy demand and environmental pressures caused by consumption of fossil fuels, the world casts their eyes on new energy, hoping to transform the existing energy structure through technological innovation to new energy field, to promote the optimization and upgrading of the world’s energy structure. The new energy in key areas of Chinese high-tech industries includes mainly nuclear power, wind power, solar power, IGCC (Integrated Gasification Combined Cycle), new energy vehicles and smart grids. The present paper will carry on an in-depth study on IGCC industry technology roadmap in China. Technology roadmap is a kind of technology management tool, expressing the structure and time dimension of technical elements’ evolution with icons. It spans a wide range of applications from a single company to industry, and national and international coalition, from detailed product technology to component technology, as well as the integration of several relevant industry technologies. The roadmap is a kind of multi-layered time-dependent icon. IGCC industry has excellent environmental characteristics and benefits, which are in accordance with the principle of coordinated development between energy and environment. Based on the analysis of current situation, market demand, industry objectives and technical barriers of IGCC technology, we highlight IGCC industrial development model with Chinese characteristics, and concisely propose the major research needs and technology projects of key technology areas in IGCC industry. We highlight IGCC industrial development model with Chinese characteristics, and concisely propose the major research needs and technology projects of key technology areas in IGCC industry. Furthermore, some relevant suggestions on IGCC technology management and industry development are put forward to promote the remarkable progress in the development of IGCC industry in China and build an efficient, economical and clean sustainable energy supply system in line with the requirements of low-carbon economy.

Employment of Two-Stage Oxygen Feeding to Control Temperature in a Downdraft Entrained-Flow Coal Gasifier

The traditional practice of employing a two-stage coal-fed gasification process is to feed all of the oxygen to provide a vigorous amount of combustion in the first stage but only feed the coal without oxygen in the second stage to allow the endothermic gasification process to occur downstream of the second stage. One of the merits of this 2-stage practice is to keep the gasifier temperature low downstream from the 2nd stage. This helps to extend the life of refractory bricks, decrease gasifier shut-down frequency for scheduled maintenance, and reduce the maintenance costs. In this traditional 2-stage practice, the temperature reduction in the second stage is achieved at the expense of a higher than normal temperature in the first stage. This study investigates a concept totally opposite to the traditional two-stage coal feeding practices in which the injected oxygen is split between the two stages, while all the coal is fed into the first stage. The hypothesis of this two-stage oxygen injection is that a distributed oxygen injection scheme can also distribute the release of heat to a larger gasifier volume and, thus, reduce the peak temperature distribution in the gasifier. The increased life expectancy and reduced maintenance of the refractory bricks can prevail in the entire gasifier and not just downstream from the second stage. In this study, both experiments and computational simulations have been performed to verify the hypothesis. A series of experiments conducted at 2.5 - 3.0 bars shows that the peak temperature and temperature range in the gasifier do decrease from 600?C - 1550?C with one stage oxygen injection to 950?C - 1230?C with a 60 - 40 oxygen split-injection. The CFD results conducted at 2.5 bars show that 1) the carbon conversion ratio for different oxygen injection schemes are all above 95%;2) H2 (about 70% vol.) dominates the syngas composition at the exit;3) the 80% - 20% case yields the lowest peak temperature and the most uniform temperature distribution along the gasifier;and 4) the 40% - 60% case produces the syngas with the highest HHV. Both experimental data and CFD predictions verify the hypothesis that it is feasible to reduce the peak temperature and achieve more uniform temperature in the gasifier by adequately controlling a two-stage oxygen injection with only minor changes of the composition and heating value of the syngas.

Simulation of Ash Deposition Behavior in an Entrained Flow Coal Gasifier

Fly ash deposition is an important phenomenon associated with ash/slag handling and discharge in the entrained-flow coal gasification process. Fouling and slagging inside the gasifier may cause reliability and safety problems because they can impose strong negative effects on the gasifier wall in the way of heat transfer and chemical corrosion. For these reasons, this study focuses on investigating the ash deposition distribution inside of a two-stage entrained-flow gasifier. The computational model is developed in order to simulate the gasification process with a focus on modeling ash formation, fly ash, and ash deposition. The Eulerian-Lagrangian approach is applied to solve the reactive thermal-flow field and particle trajectories with heterogeneous reactions. The governing equations include the Navier-Stokes equations, twelve species transport equations, and ten global chemical reactions consisting of three heterogeneous reactions and seven homogeneous reactions. The coal/ash particles are tracked with the Lagrangian method. The effects of different coal/ash injection schemes and different coal types on ash deposition have been investigated. The results show that the two-stage fuel feeding scheme could distribute the ash throughout a larger gasifier’s volume and, hence, could reduce the peak ash deposition rate and make the ash distribution more uniform inside the gasifier. Gasification of a high-ash coal results in a high ash deposition rate, low syngas higher heating value (HHV), and low carbon conversion rate. The result of ash deposition rate in this study can be used as a boundary condition to provide ash particle influx distribution for use in slagging models.

气化炉内熔渣流动特性预测模型的研究进展

双碳战略目标下,煤气化技术将会是我国未来煤炭领域的重要发展路线。在煤气化技术推广应用中,熔渣的流动行为严重影响气化炉的平稳运行时长,间接影响合成气的质量和炉壁的热量损失,有效求解流动参数的熔渣流动特性预测模型备受关注。本研究论述了现有的气化炉内熔渣流动特性的预测模型,并展望了预测模型的未来研究方向。综述当下,预测模型根据熔渣流动维数可分为一维预测模型和二维预测模型;一维稳态和非稳态预测模型均经历了构建和完善阶段;二维预测模型因无相关的数学公式描述和流动理念假设尚处于构建阶段;通过对液态熔渣的温度分布、附加应力的取舍,临界黏度的选取和熔渣黏度的处理方式等方面可以提高模型的计算精度。展望未来,一维预测模型的应用场景需更完善的规定,针对稳态和非稳态预测模型求解的参数需要更细致的辨析;二维预测模型的构建理论需更详细的突破,明确非稳态工况下熔渣在轴向和周向上流动的优先级;流动预测模型的计算精度需更全面的提升,熔渣性质的非恒定性、熔化的不均匀性、烟气流速的波动性等因素需要侧重考虑。

煤化工生产技术路线及产品现状

中国煤炭资源丰富,是我国重要的能源资源,传统煤炭加工过程中能耗高,污染大,对环境和人体健康产生严重影响。在“双碳”背景、能耗双控政策影响下,选择合适的路线生产具有市场竞争力的产品是一个战略性的问题。文章从煤炭焦化、气化、液化三个方面综述了煤化工生产的技术路线及产品现状,并对其发展趋势进行预测,以期为煤化工产品路线选择提供参考。

煤气化渣活化过硫酸盐体系氧化去除菲

采用固体废弃物煤气化渣(CGS)作为过硫酸盐(PS)的活化剂,考察CGS/PS对菲的去除性能。使用SEM-EDS、XPS表征了CGS的微观结构和元素组成;通过自由基掩蔽实验和电子顺磁共振(EPR)实验确定自由基种类;考察了CGS质量浓度、PS初始浓度、初始pH、共存离子对CGS/PS体系中菲去除率的影响,探讨了反应机理并推测降解路径,并使用ECOSAR软件评估菲及其产物的毒性。结果表明,CGS中Fe元素质量分数为11.9%,可有效活化PS。在菲质量浓度为1 mg/L、pH=3、CGS质量浓度为0.7 g/L、PS初始浓度为1 mmol/L的条件下,60 min后CGS/PS体系对菲的去除率可达95.34%,PS的利用率为29.18%。菲降解过程符合伪一级动力学模型,CGS/PS体系产生了SO_(4)^(–)•和•OH,且SO_(4)^(–)•在菲降解过程中起主要作用,共存离子HCO_(3)^(–)、NO_(3)^(–)对反应的抑制作用较显著。菲主要通过去羰基、羟基化、脱碳等反应分解为长链酸、酯,最终转化为CO_(2)和H_(2)O。ECOSAR模型评估发现,菲降解的中间产物毒性普遍低于菲。

电力市场环境下生物质气化耦合燃煤机组与风电场联合自调度优化策略

利用生物质气化耦合燃煤发电技术可以提升火电机组的燃料及运行灵活性,从而促进风电的高水平消纳,同时实现生物质能的有效开发利用。该文首先建立反映生物质气化耦合热电联产机组内部能流过程和外部出力特性的运行模型。然后,从能源供应商视角出发,给出耦合机组与风电场联合参与日前、日内和实时平衡市场的多阶段决策框架,提出反映联合体期望收益和条件风险价值的多目标自调度策略。最后,利用基于字典优化框架的增强ε约束法,给出构建帕累托前沿的多目标优化求解流程。以一台350 MW燃煤热电联产机组和一座600 MW风电场构成的联合体为例进行分析。结果可知,增设生物质气化子系统和联合运行能够使其经济效益提升6%左右,同时有利于降低能源供应商的运营风险。

煤气化灰渣烘烤球磨活化技术研究

为了提高煤气化灰渣的活性,增加煤气化灰渣资源化利用的途径和范围,实现煤气化灰渣的高值化利用,采用烘烤-球磨-筛分的方法对其进行处理。通过粒径分布试验和SEM试验分析活化前后、不同研磨时间的煤气化灰渣的粒度分布和物质形态,发现颗粒细度直接影响煤气化灰渣的活性,而煤气化灰渣颗粒的分布特征会影响胶凝材料整体的紧密堆积,从而决定硬化体的微观密实程度。通过活化前后的煤气化灰渣与熟石灰的抗压和抗折强度试验验证煤气化灰渣烘烤球磨活化技术的有效性。结果表明:活化后的煤气化灰渣混合料的抗折和抗压强度是未经过活化的煤气化灰渣熟石灰混合料的1.4~3.0倍,证明了煤气化灰渣活化技术的可行性。

壳牌煤气化技术优化与评估

分析了壳牌煤气化技术优化与评估的措施。综述了壳牌煤气化技术的应用现状,探讨了其技术工艺流程和工艺系统。针对技术效率提升,提出了优化煤烧嘴角度、增强压缩机激冷能力以及改进吹灰器和敲击器设计等措施。探讨了提高煤粉利用率、优化合成气冷却过程及提升系统自动化水平等降成本措施。建立了层次结构模型,确定了优化气化技术的评价标准和子标准,进行了风险评估,得出所提优化措施能有效提升壳牌煤气化技术的效率,并能降低成本。提出了优化后技术的实施计划、资源配置、技术支持及风险评估与应对措施,为壳牌煤气化技术的持续优化和应用提供了指导。

粉煤气化技术应用及相关问题研究

粉煤气化技术作为一种高效、环保的能源转化技术,在国内外得到了广泛的应用。文章概述了粉煤气化技术的技术原理、工艺流程和技术优势,如能量转化率高、污染物排放低等。然而,粉煤气化技术在实际应用中也面临一些问题,如原料适应性、系统稳定性、环保标准等。针对这些问题,本文提出了相应的解决方案和建议。期望随着环保意识的提高和能源结构的调整,粉煤气化技术的应用将更加广泛。

国内外煤炭地下气化(UCG)技术调研综述

煤炭地下气化(UCG)技术通过将气化剂注入地下煤层,生成合成气供能源或化工利用,具有高效、低碳等优点。综述国内外UCG技术的发展历程、技术进展、应用现状、面临的挑战及未来发展方向。国外方面,美国、苏联及欧盟国家通过长期试验和技术探索,形成了现代UCG技术体系,但仍面临气化通道稳定性、环境污染等挑战。国内UCG技术研究起步较晚,但在国家科技计划支持下,近年来在气化通道建设、气化过程控制等方面取得显著进展,并成功建成多个示范工程。然而,UCG技术的产业化进程仍面临地质条件复杂、技术难度高及经济投入大等挑战。未来,需加大技术创新和研发投入,推动示范项目和商业化应用,加强国际合作与交流,并注重环境保护和生态安全,以实现UCG技术的可持续发展,为能源结构转型和可持续发展战略提供重要支撑。

煤气化渣资源化技术开发与研究利用进展

随着煤气化技术的蓬勃发展,煤气化渣的产量及堆存量越来越多。目前对煤气化渣的处理引起广大学者的关注,煤气化渣综合利用率低,已严重污染土地、水源及大气。鉴于此,系统介绍了煤气化渣的来源及特点,综述了国内外煤气化渣在建材原料、土壤改良、水体修复及残炭利用等领域的研究与应用现状。基于上述分析提出针对不同特点的煤气化渣应制定特定的利用方式,以最大限度发挥其潜能;促进煤气化渣综合利用的关键技术是残碳分离和富集;规模化处理和与精细化的合理结合将是煤气化渣利用的发展趋势。