硝酸钾结晶器蒸汽喷射增压器的设计与CFD分析

结合硝酸钾冷却结晶实际生产的各项参数,通过严格的理论计算,设计出与生产相匹配的蒸汽喷射增压器,以提高蒸发器的产能和运转周期,降低能耗。并采用流体动力学计算软件Fluent对硝酸钾冷却结晶的蒸汽喷射增压器的工作过程进行数值模拟。比较分析了不同的X（喷嘴出口到吸收室入口的距离）值对流场的影响。结果表明,在一定的工况参数下,蒸汽喷射增压器的流场与X值有着密切的联系。通过数值模拟计算得到,当X=0.01 m时,设计的增压器有效降低了激波引起总压的耗损和减小喷射气流速度的突变,同时在实际生产中得到了良好的应用。      

Recent advances in the catalytic pyrolysis of biomass

Biomass is considered as a renewable and alternative resource for the production of fuels and chemicals, since it is the only carbon and hydrogen containing resource that we can find in the world except for fossil resources, capable of being converted to hydrocarbons. The pyrolytic liquefaction of biomass is a promising way to convert biomass to useful products. This paper briefly surveys the present status of the direct catalytic pyrolysis for the liquefaction of biomass. The direct use of catalysts could decrease the pyrolysis temperature, increase the conversion of biomass and the yield of bio-oil, and change the distribution of the pyrolytic liquid products then improve the quality of the bio-oil obtained. The fact that biomass is in solid state present great challenges for its conversion and for the effective use of catalysts due to the bad heat transfer characteristics and bad mass transfer properties. These barriers appeal for the development of a new catalyst and new catalytic process as well as the integration of both. Process design and process intensification are of significant importance in the catalytic conversion of biomass.     

Kinetic and structural studies of the polymerization of N,N′‐bismaleimide‐4,4′‐diphenylmethane with barbituric acid

Both the isothermal and non‐isothermal polymerizations of N,N′‐bismaleimide‐4,4′‐diphenylmethane (BMI) with barbituric acid (BTA) were investigated by the differential scanning calorimeter. The experimental results showed that the polymerizations of BMI with BTA were governed by the competitive Michael addition reaction and free radical polymerization mechanisms. Furthermore, the contribution of free radical polymerization becomes more important when the mole fraction of BTA decreases. ¹H NMR and ¹³C NMR measurements further support the coexistence of the Michael addition reaction and free radical polymerization mechanisms. A preliminary kinetic model that took into account the competitive Michael addition reaction and free radical polymerization mechanisms was developed. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers     

基于两阶段风险分析的水库群汛期运行水位动态控制模型

水库(群)实时调度能结合有效的水文预报信息对水库在实时运行层面权衡防洪与兴利效益具有指导意义。然而,水文预报信息的利用面临着不可规避的不确定性问题,故水库(群)实时调度运行需要考虑风险控制方法的研究。针对耦合水文预报的水库群汛期运行水位动态控制问题,提出了可考虑各水库不同预见期长度、不同预报精度的两阶段风险率计算方法,并将其应用于构建水库群汛期运行水位动态控制模型。首先,两阶段风险率思想是将未来调度时段按预见期节点分为预见期以内和预见期以外两个阶段,预见期以内考虑径流预报不确定性带来的风险,采用集合预报思想统计多组预报径流情景在预见期以内的失事概率,预见期以外考虑因预见期末水位过高难于应对后续洪水的潜在风险,根据历史设计洪水的调洪演算试算风险率。其次,基于所提出的两阶段风险率方法构建以发电量最大为目标函数的水库群汛期运行水位动态控制模型。研究结果表明：提出的两阶段风险率计算方法可兼顾考虑实时调度阶段由径流不确定性引起的预见期以内、预见期以外的潜在风险;基于两阶段风险分析构建的水库群优化调度模型,可求解得出的水库群系统库容动态最优决策过程,且该优化调度模型可在不增加汛期防洪风险的基础上提高水库群系统的发电效益,即2010年汉江流域五库系统在夏汛期可提高总发电量2.30亿kWh。     

GS-08乙苯脱氢催化剂在广石化的应用

乙苯脱氢催化剂GS-08催化剂在广州石化总研制的首次应用。     

过氧化氢氧化法合成C.I.酸性紫17

在催化剂存在下，以N-乙基-N-苄基苯胺磺化物与对-（N，N-二乙基）氨基苯甲醛在酸性条件下于95℃-100℃进行缩合。在pH=5-6时，用30%过氧化氢氧化，合成了C.I.酸性紫17,氧化收率86.5%。成品中铬含量为10.8mg/kg。     

常压合成防老剂4020的工业生产工艺

以小试和中试条件为依据，研究了防老荆4020[N-(1，3-二甲基丁基)-N′-苯基对苯二胺]的工业生产新工艺。以对氨基苯酚、甲基异丁基酮、甲酸和苯胺为原料，用三步法在常压下合成了防老荆4020。优化的工艺是用3台反应釜并联，差时1／3个生产周期分别开工，用1台同客积的蒸馏釜与之配套，并在4台釜中都装有冷却蛇管。该工艺设备投资低，生产用时短，产物收率达90.1％。     

干-喷湿纺聚丙烯腈纤维拉伸工艺研究

研究了干 -喷湿纺聚丙烯腈 (PAN)初生纤维的喷丝头拉伸比和三级拉伸 (空气拉伸、DMF浴拉伸、热水和沸水拉伸、干热拉伸 )工艺中各拉伸比对纤维性能的影响。结果表明 :提高喷丝头拉伸比可明显地降低初生纤维的线密度 ,提高强度 ;三级拉伸工艺中各拉伸比的提高均有利于PAN纤维线密度的减小及其强度、声速取向度和抗张模量的提高 ;合理调配三级拉伸中各拉伸比可制得强度超过 7.0cN/dtex的PAN纤维     

罗汉果渣中水溶性膳食纤维提取工艺的研究

使用正交实验探讨了用化学法从罗汉果渣中提取水溶性膳食纤维的最佳工艺 ,得到最佳工艺条件为 :水浴温度T =95℃ ,pH =5 .0 ,提取液用量为 5mL·g-1,提取时间为15min。在该条件下提取率为 2 .2 1%。再使用目前国际通用的Prosky法一酶解法提取水溶性膳食纤维 ,其提取率为 4.40 %。结果显示 ,单纯从水解工艺来说酶解法优于化学法     

Al_2O_3/金属多相材料研究进展

阐述了Al2 O3 /金属多相材料的研究进展状况 ,对目前已经研究的体系、制备工艺、显微结构与性能以及目前存在的问题和发展趋势等进行了概括 ,重点对其功能化进行了比较详细的阐述。此外 ,也介绍了我们在功能化方面所得到的一些有用的结果。