Pretreatment and physical activation of acetylene cokes

Pretreatment of acetylene cokes at 450 °C with a mixture of nitrogen, oxygen and water vapour creates a relatively large surface area and some initial microporosity, further developed by water activation at 800 °C. For the same degree of burn-off, but without pretreatment, large micropores (L > 2–3 nm) are obtained and the external surface area remains small.     

Influence of volatile matter and deposited carbon on coke yield from coals

The relations between coke yields and the volatile matter content of 30 individual and 30 blended coals were investigated. Coke yields and deposited carbon related to volatile matter content can be expressed in the following equations: CY (%) = 97.89?0.86 VMch+VMc; and DC (%)= ?2.24+0.16 VMch; where: CY=real coke yield; VMch = volatile matter content of charging coal; VMc=volatile matter content of coke, and in the case of <2%; DC = deposited carbon. The test results show excellent correlation with practice.     

Catalysis of gasification of coal-derived cokes and chars

Calcium is the most important in-situ catalyst for gasification of US coal chars in O₂, CO₂ and H₂O. It is a poor catalyst for gasification of chars by H₂. Potassium and sodium added to low-rank coals by ion exchange and high-rank coals by impregnation are excellent catalysts for char gasification in O₂, CO₂ and H₂O. Carbon monoxide inhibits catalysis of the CH₂O reaction by calcium, potassium and sodium; H₂ inhibits catalysis by calcium. Thus injection of synthesis gas into the gasifier will inhibit the CH₂O reaction. Iron is not an important catalyst for the gasification of chars in O₂, CO₂ and H₂O, because it is invariably in the oxidized state. Carbon monoxide disproportionates to deposit carbon from a dry synthesis gas mixture (3 vol H₂ + 1 vol CO) over potassium-, sodium- and iron-loaded lignite char and a raw bituminous coal char, high in pyrite, at 1123 K and 0.1 MPa pressure. The carbon is highly reactive, with the injection of 2.7 kPa H₂O to the synthesis gas resulting in net carbon gasification. The effect of traces of sulphur in the gas stream on catalysis of gasification or carbon-forming reactions by calcium, potassium, or sodium is not well understood at present. Traces of sulphur do, however, inhibit catalysis by iron.     

两种不同原料制备无粘结剂高强度炭材料的研究

分别以生石油焦和煤系原料改性炭粉为原料成功制得了无粘结荆高强度炭材料。实验表明：原料挥发分含量较高对粉料的成型有利，但挥发分含量过高，不利于无粘结剂炭材料的烧结；另外，随着成型压力的增加，生坯密度和无粘结荆炭材料烧结制品的密度都呈升高的趋势。研究结果表明：成型压力为IOOMPa，烧结温度为1000℃，生石油焦粉制得的无粘结剂炭材料的抗折强度为42．90MPa，抗压强度为90．23MPa；煤系原料改性炭粉制得的无粘结剂炭材料的抗折强度为61．58MPa，抗压强度为116．12MPa。     

武钢干、湿法熄焦焦炭性能对比研究

为了研究干、湿法熄焦焦炭性能之间的差异,对武钢的干、湿法熄焦焦炭进行了常规、粒度、结构、强度、热性能、催化、光学组织等性能的对比分析研究.研究结果表明:与湿法熄焦焦炭相比,干法熄焦焦炭在平均粒度、粒度均匀系数、机械强度、热性能等方面均有明显改善;灰成分催化指数MCI、光学组织指数OTI基本不变;而吸碱能力强,抗碱能力弱,但是吸碱后的热性能仍优于湿法熄焦焦炭;吸硼能力弱、钝化效果差,钝化后干法熄焦焦炭的热性能稍低于湿法熄焦焦炭.     

石油系油浆与煤系闪蒸油的焦化性能Ⅱ. 焦化条件的影响

考察了焦化温度和焦化压力对石油系油浆与煤系闪蒸油聚合后所得物料焦化性能的影响。根据在不同焦化条件下所得焦块光学结构的好坏确定了最佳的焦化温度和焦化压力分别为500℃和1MPa,并在此条件下应用"放气拉焦"的方法制得了以纤维为主的流线型光学结构的针状焦。     

Correspondence between the composition and plastic properties of British coals and the structural properties and reactivity of the corresponding cokes

The chemical composition and the physico-chemical properties of a suite of British coals, mainly of types 501/2 as defined by the NCB classification, but including some coals of higher and lower rank (NCB classification 204,401/2 and 601/2), were comprehensively investigated. Each coal was subsequently carbonized under controlled conditions of size distribution, bulk density and temperature on the 250 kg scale and the tensile strength, coke structure and coke reactivity were determined. This data highlighted the significance of the atomic ratio of the oxygen and carbon of the coals and the lack of relations between coal properties and coke structure and strength. As regards coke reactivity only complex relations with coal properties could be found, with coal rank, the oxygen/carbon ratio and the chlorine content being of greatest importance.     

Steam gasification of coal cokes in an internally circulating fluidized bed of thermal storage material for solar thermochemical processes

A laboratory-scale prototype windowed internally circulating fluidized-bed reactor made of quartz sand and coal coke particles was investigated for steam gasification using concentrated Xe-light radiation as the energy source. The quartz sand was used as a chemically inert bed material for the fluidized bed, while the coal coke particles functioned as the reacting particles for the endothermic gasification reaction. The advantages of using quartz sand as the bed material for the directly irradiated gasification reactor are as follows: (1) The bed height is maintained at a constant level during the gasification. (2) The quartz sand functions as a thermal transfer/storage medium inside the reactor. The gasification performances such as the production rates of CO, H₂, and CO₂; carbon conversion; and light-to-chemical energy conversion were evaluated for the fluidized-bed reactor with a thermal transfer/storage medium (quartz sand). The effects of using the bed material (quartz sand) on the gasification performance are described in this paper.     

Causes Leading to Formation of Shot Cokes and Measures for Its Prevention in Super Viscous Oil Delayed Coking Unit

Shot cokes are frequently formed in the delayed coking unit treating the super viscous oil at PetroChina＇s Liaohe Petrochemical Company. Considerable work has been carded out to avoid the formation of shot cokes. The test results obtained have shown that the property of super viscous oil has played a key role in the formation of shot cokes. After adjusting and optimizing the process indices the operating regime of the delayed coking unit at a throughput of 118t/h of the super viscous oil is specified as follows： a reaction temperature of 498-502℃, a reaction pressure of 0.17-0.25 MPa, a recycle ratio of 0.5-0.6 and a fractionation tower bottom temperature of 355-365 ℃. In the meantime, the delayed coking process has adopted measures to enhance pre-fractionation of the feedstock to rationally remove light fractions and maintain a steady gas velocity in order to avoid the formation of shot cokes.     

南钢公司焦炭质量的提高及措施

根据南钢公司焦炭质量的现状 ,总结了提高焦炭质量的具体措施 ,并指出了存在的问题 ,对强化高炉冶炼有一定现实意义。