Shell粉煤气化炉炉温控制方案的探讨

Shell粉煤气化炉的反应温度无法直接测量。目前通过测量出气化炉合成气中CO2含量来控制气化炉的O2/C，从而控制炉温，滞后时间太长。提出用带有前馈信号的二氧化碳控制器来控制炉温，提高温度控制的及时性和可靠性。     

浅谈Shell气化炉温度的控制

论述控制气化炉炉温的重要性,分析气化炉温度控制要点,提出炉温调整的方法.     

基于Deltav控制系统对气化炉炉温控制指标的改进及应用

介绍了Shell气化炉炉温控制指标,分析了各项炉温控制指标的优缺点,通过筛选对比,选择热负荷作为气化炉炉温新的控制指标,利用现有的Deltav控制系统,简化了热负荷的计算结果。热负荷控制和常规的蒸汽产量控制炉温的对比结果表明,选择热负荷作为气化炉炉温控制指标,不受气化炉负荷、锅炉给水温度、炉水温度、汽包压力等影响,能够平稳快速的反映气化炉炉温,有利于将气化炉温度控制在合理的范围之内。     

Texaco水煤浆气化炉炉膛温度监测手段分析

介绍了Texaco水煤浆气化工艺气化炉炉膛温度控制的重要性,提出了通过利用热电偶直接测量法、甲烷含量与温度的近似线形关系、工艺气组分走势判断法及炉渣与气化炉压差法等,来综合判断气化炉炉温,以备指导实际生产。     

粉煤气化炉反应炉温的相关参数分析

介绍了不同炉温控制对气化炉运行的影响,论述了设计炉温控制参数的不足之处,通过合成气冷却器入口温度、气化炉激冷段与输气段密度、渣池壁温、渣锁斗与气化炉压差等多种参数分析,寻求合适的装置粉煤气化炉温控参数指标。     

壳牌气化炉饱和蒸汽产量和水汽密度相互校验模型及在炉温控制中的应用

壳牌气化炉现有工业生产规模应用的炉温控制方法主要有两种:一是传统通过监控气化炉水冷壁的饱和蒸汽量(F)来监控气化炉炉温;二是通过监控气化炉水冷壁出口水汽密度(ρ)及通过水汽密度计算的热负荷(J)来监控气化炉炉温。两种方法的基础是准确的仪表测量值(ρ)及(F)。实际运行过程中,由于ρ、 F测量仪表无法在线校准,当测量仪表发生漂移时就会给工厂技术人员带来误判。本文基于壳牌气化炉运行原理,借助工程计算软件给出了蒸汽产量(F)和水汽密度(ρ)的相互校验模型;工业应用结果表明,应用该模型可在确定F和ρ中一个参数准确量的情况下即可模拟计算获得另一个参数值,与测量值进行对比与修正,达到正确监控炉温的目的。     

天津IGCC电站二段式气化炉炉温控制要点浅析

IGCC发电技术是目前最具发展前景的清洁高效煤电技术,华能天津IGCC电站采用自主研发的二段式干煤粉气化炉。针对天津IGCC电站所采用的二段式气化炉设备特点,基于生产现场实际操作过程,文章分析了水汽密度与气化炉炉况之间的变化规律,提供了一种根据两个水汽密度参数调整炉温控制,平衡炉况的新方法,对二段式气化炉运行中炉温炉况控制具有一定的指导作用。     

IGCC气化炉炉温的测算方法

由于气流床气化炉内温度较高,环境复杂,受高温熔渣和高温气流的影响,直接测量炉内温度较为困难。因此,以热传导模型为基础,通过对气化炉烧嘴罩传热过程的分析,提出估算气化炉内温度的公式,并以此计算出温差与气化炉内温度的分段曲线。与现有气化炉温度分段曲线的对比结果表明:该方法能够更为准确地估算炉膛温度,适合气化炉内温度控制。而且,该方法不需要额外增加任何设备。     

气化炉炉温测量与控制

气化炉是德士古水煤浆加压气化制合成气工艺最关键的设备。气化炉炉温控制是煤气化工艺控制的重要环节。炉温控制的好坏不仅直接影响气化炉的使用寿命及生产的安全性，同时还制约着气化效率，影响产量。我厂弓惯的德士古气化装置，1993年投运后，也存在一些问题，我们采取措施，较好地控制了炉温。1气化炉炉温测量炉温过低碳转化率低，气化效率低；炉温过高，易损坏耐火材料。气化炉由燃烧室和激冷室组成。燃烧室在气化炉上部，是气化反应区，温度高达1300C。激冷室在气化炉下部，温度较低。气化炉炉温测量主要是测燃烧室温度，有测量炉膛…     

SHELL气化炉控制应用及发展前景

Shell干法粉煤加压气化是一种高效率、低污染的先进煤气化方法。简要介绍了Shell干法粉煤加压气化的工艺原理、技术特点以及气化炉温度控制方法,以及炉温波动带来的次生后果,并指出了该工艺在煤化工领域的应用前景。     

烟煤水煤气气化炉运行的可行性分析

烟煤水煤气气化炉是将双火层煤气发生炉的气化原理用于水煤气气化的一种炉型。介绍了双火层气化炉的炉型规格、供气形式和半水煤气组成;从煤气中CO2和CH4含量、气化炉反应温度、蒸汽量的调整等方面分析了烟煤水煤气气化炉生产运行的可行性;介绍了烟煤水煤气气化炉的结构形式和工艺流程;计算了原料煤成本的经济效益,结果表明,4万t/a合成氨装置每年可节约原料煤费用1160万元,20万t/a甲醇装置每年可节约原料煤费用6960万元。     

壳牌气化炉热负荷用于控制反应温度的论析

提出了通过气化炉热负荷的变化,控制壳牌气化炉内气化反应温度的新思路。论述了气化炉热负荷的计算方法及其用于控制气化炉反应温度的优势;通过生产运行数据,对比了不同参数变化对气化炉热负荷和蒸汽产量的影响;结果表明,气化炉热负荷参数能够更真实地反映气化炉的操作状态。     

Coal char temperature profile estimation using optical reflectance for a commercial-scale Sasol-Lurgi FBDB gasifier

In the Sasol-Lurgi fixed-bed dry-bottom (FBDB) gasifier the temperature in the combustion zone should not exceed the melting point of the ash-forming minerals, causing them to melt/flow and agglomerate. Sintering of ash particles is considered desirable in Sasol-Lurgi FBDB gasification, since it promotes easy gas flow, whereas clinkering creates channeling and localized “hot spots”, leading to unstable gasifier operation. Due to the counter-current mode of operation, hot ash exchanges heat with the cold incoming agent (steam and oxygen), while at the same time hot raw gas exchanges heat with cold incoming coal. This results in the ash and raw gas leaving the gasifier at relatively low temperatures compared to other types of gasifiers, which improves the thermal efficiency and lowers the steam consumption.Vitrinite reflectance analyses were performed on a range of Sasol-Lurgi MK IV commercial-scale gasifier turn-out samples, applying ISO standards 7404-5. Average temperature profile measurements of the solid particles, successfully revealed the temperature range occurring within the various zones of the gasifier. The average (mean) temperature ranged from ca. 400 °C up to 850 °C within the pyrolysis region. In this region of the gasifier, the particle surface temperature and peak temperature showed visible evidence of heat transfer limitations occurring through lump coal when compared to the mean particle temperature. This provides some evidence of the complex radial and localized behaviour occurring within the averaged axial sample slices. In the oxidizing and combustion regimes, exothermic conditions prevail and heat transfer differences across the particles are minimized. A characteristic spike, indicative of an increase in temperature, was found in the sample taken directly above the ash-grate, seeming to indicate that agent distribution through the nozzles positioned just above the grate is not uniform, resulting in localized oxygen concentration increases with subsequent “hot-spots” and channel-burning occurring. Homogenization of the ash bed could help to optimize the agent distribution within the reactor.The surface temperature profile of the gasifier solids was thus found to be in reasonable agreement with literature, albeit that different coal types and temperature profile estimation methods were utilized.     

Biomass Gasification Integrated with Chemical Looping System for Hydrogen and Power. Coproduction Process – Thermodynamic and Techno‐Economic Assessment

Three biomass gasification‐based hydrogen and power coproduction processes are modeled with Aspen Plus. Case 1 is the conventional biomass gasification coupled with a shift reactor, cases 2 and 3 involve integration of biomass gasification with iron‐based and calcium‐based chemical looping systems. The effects of important process parameters on the performance indicators such as hydrogen yield and efficiencies are evaluated by sensitivity analyses. These parameters include gasification temperature, molar ratios of steam to biomass in the gasifier, Fe₂O₃ to syngas in the fuel reactor, Fe/FeO to steam in the steam reactor, CaO to CO, and steam to CO in the carbonator. The energy and exergy balance distributions for the above three cases are comprehensively discussed and compared. Furthermore, techno‐economic assessments are performed to evaluate the three cases in terms of capital cost, operating cost, and leveled cost of energy.     

Experimental study of a commercial circulated fluidized bed coal gasifier

This paper presented the performance data of a commercial scale circulating fluidized bed gasifier, CFBG-800-I. The operation condition effects on gasifier temperature distribution and gasifier performance were studied. It is found that the external cycle has a critical influence on the gasifier temperature profiles. Both the Air/Coal ratio and Steam/Coal ratio affect the bed temperature. The increasing in Air/Coal ratio decreases the valuable gases content, which is adverse to the gasifier performance but increases the gasifier temperature, which is favorable for the gasification reactions. The best choice of the Air/Coal ratio is a tradeoff of gasifier performance and gasifier temperature. The Steam/Coal ratio could influence gasifier temperature and gasifier performance in several ways. Increasing steam increased the water gas reaction and the CO, H₂ concentrations increase firstly, and then decrease at a Steam/Coal ratio of 0.32. Increased Steam/Coal ratio decreases the bed temperature, which is bad for the gasifier performance, and will decrease the carbon conversion efficiency. The Steam/Coal ratio should be carefully selected by comprehensive evaluation also.     

气化剂配比对气化炉性能的影响

为了实现能源利用的可持续发展,多联产技术可以对能量进行合理的利用.多联产系统不同于化工或动力分产系统,对气化炉性能有更具体的要求.通过化学平衡和热量平衡方法求解气化炉平衡工作温度以及该温度下的出口煤气成分,研究了气化炉进口气化剂配比对出口煤气成分、冷煤气效率、热效率及火用效率的影响,指出热效率、火用效率最优情况下适应于各煤种的最优氧煤比以及合理的水蒸气耗量,为多联产系统的设计优化提供参考.     

串行流化床煤气化试验

针对串行流化床煤气化技术特点,以水蒸气为气化剂,在串行流化床试验装置上进行煤气化特性的试验研究,考察了气化反应器温度、蒸汽煤比对煤气组成、热值、冷煤气效率和碳转化率的影响。结果表明,燃烧反应器内燃烧烟气不会串混至气化反应器,该煤气化技术能够稳定连续地从气化反应器获得不含N₂的高品质合成气。随着气化反应器温度的升高、蒸汽煤比的增加,煤气热值和冷煤气效率均会提高,但对碳转化率影响有所不同。在试验阶段获得的最高煤气热值为6.9 MJ•m^-3,冷煤气效率为68％,碳转化率为92％。     

双阳煤在PKM气化炉试烧总结

介绍了在PKM气化炉中弱粘结性双阳煤的试烧情况,并给出了主要工艺参数控制范围。试烧结果表明:依兰煤中配入50%双阳煤,汽氧比6.0:1时,气化炉工况良好。     

操作变量改变对德士古渣油气化炉燃烧影响的研究

采用综合模型对德士古渣油气化炉进行数值计算，分别模拟了油-蒸汽混合物中水蒸汽比例提高10％和20％以及氧气相对于渣油的比例提高5％和10％的情况下，渣油在德士古气化炉燃烧室内的燃烧情况。计算的结果发现提高水蒸汽比例将降低体系的温度，但同时也降低转化率。氧气比例的提高将提高主产物在产物中的比例，转化率增加，但同时提高了燃烧室内的温度。     

COAL GASIFICATION AND THERMODYNAMIC CALCULATION OF MOVING BED COAL GASIFIER WITH DRAFT TUBE

The coal gasification experiment and thermodynamic calculation of the newly developed moving bed coal gasifier with a draft tube are done according to the thermodynamic calculating model built on the basis of chemical reaction equilibrium, mass balance and heat balance. The obtained experimental results are quite approaching to the thermodynamically calculated values. The effects of steam/coal ratio, air/coal ratio, reaction temperature, reaction pressure, steam temperature, air temperature on the thermodynamic indexes of the gasifier are examined through thermodynamic simulating calculations. Under the optimal simulating conditions, gas calorific value, cold gas thermodynamic efficiency and available energy efficiency can reach 12 MJ/Nm³, 88.6% and 95.4% respectively, when air is used as the oxidizer. Compared with the directly-burning-coal-gasifier, the gasifier exhibits good characteristics and prospects for industrial application.