Experimental investigation on the distribution uniformity and pressure drop of perforated plate distributors for the innovative spray-type packed bed thermal storage

As an innovative thermal energy technology, the spray-type packed bed has advantages of high efficiency and low cost. A liquid distributor is the key component for the spray-type packed bed for scattering heat-transfer liquid drops evenly. In this study, the distribution performance and pressure drop of the perforated plate distributors of different orifice diameters were studied experimentally. The experimental results indicate that orifice diameter has a greater effect on the distribution performance compared to flow rate. With an increase in flow rate, the flow pattern through the distributor changes from the uncovered drop to the covered drop and then to the jet flow. The covered drop pattern shows the best performance with a good distribution and a small pressure drop simultaneously, which is the design and optimization principle of the distributor for a spray-type packed bed.     

Numerical investigation on cold flow dynamics of supercritical water fluidized bed reactor with inclined distributor: Design and scale up

Supercritical water fluidized bed reactor (SCWFBR) is a novel concept for the gasification of coal and biomass to produce hydrogen. In this work, to enhance the mixing in the axial direction, an inclined distributor is introduced to optimize the flow dynamics in SCWFBR with partitioned fluid supply. Through numerical simulations based on the two fluid model (TFM), the effects of the inclined distributor structure and operating parameters on the solid distribution and the residence time are evaluated with the optimal values determined. Numerical results show that, area ratio = 2:1, SCW velocity ratio = 3:1, flow ratio = 3.36:1 and inclination angle = 20° are the optimal design in this paper. A predictive correlation of the minimum fluidization velocity for the improved SCWFBR is also proposed based on the numerical data. The average error between the correlation and numerical simulation results is approximately 1.4% which strongly demonstrates its capability. Finally, based on the optimal design, the lab-scale reactor is further scaled up and the studies about two scale-up rules are carried out. Only the cold flow is simulated in this study without considering chemical reaction which would be involved in future work.     

三相流化床电极反应器深度处理制浆废水

应用三相流化床电极反应器(新型电化学反应器)处理制浆废水.研究了曝气量、槽电压、溶液pH值及FeSO4浓度等因素对电解效果的影响.结果表明,该反应器深度处理制浆废水的最佳工艺条件为:槽电压20 V,曝气量为0.3 m3.h-1,FeSO4浓度为1000 mg.L-1,pH值≈2.5,反应时间为90 m in时COD去除率为70.1%.     

循环流化床粉煤灰可控制备高纯F型八面沸石研究

利用粉煤灰制备沸石分子筛是其高值化利用的重要方向之一.以循环流化床粉煤灰为原料,采用酸浸预处理-氢氧化钠碱熔活化-水热晶化法制备F型八面沸石,并用于吸附亚甲基蓝.考察酸浸温度、碱熔温度及碱灰质量比对粉煤灰结构的影响及碱熔温度、碱灰质量比、液固比及晶化时间对沸石的结构和形貌的影响.通过XRD和SEM对粉煤灰沸石的晶体结构和形貌进行表征.结果表明,利用循环流化床粉煤灰制备高纯F型八面沸石适宜条件为碱熔温度550℃,碱灰质量比1.5:1,液固比12 mL/g,晶体导向剂用量10;,晶化温度100℃,晶化时间20 h.其比表面积高达357 m2/g,且对亚甲基蓝的饱和吸附量高达178 mg/g.     

Continuous Production of Thermostable α-Amylase by Immobilized Bacillus Cells in a Fluidized-Bed Reactor

The exponential cells ofBacillus cereus immobilized in calcium alginate and spun into microcylindrical particles were used in a fluidized-bed reactor for continuous synthesis of thermostable α-amylase. The reactor was operated over a period of 30 d with a dilution rate of 0.33 h^-1, producing 1000–1200 U/mL of enzyme. The productivity of the reactor was in the range of 330–396 kU/h. A 20-fold increase in the productivity with respect to batch fermentation with free cells was attained.     

福建无烟粉煤催化气化

报导了福建无烟粉煤在碱性催化剂作用下的催化气化工作进展,在小型Φ１８ｍｍ固定床与Φ２０ｍｍ流化床中,进行了水蒸气气化、混合气（空气／水蒸气）气化,采用复合１催化剂添加量８％,８５０～９００℃及流化床条件下,即可获得产气率Ｖ＞３ｍ３／ｋｇ煤（无催化剂时,Ｖ＜１．６ｍ３／ｋｇ煤）及煤气热值ＱＬＶＨ＞９ＭＪ／ｍ３（水蒸气气化）与＞６ＭＪ／ｍ３（混合气气化）的结果,并与无烟煤气化的工业装置进行了比较,这为无烟粉煤有效转化的工业化试验提供了最重要的依据     

气固射流床射流深度的研究

在３００×５１×２６００ｍｍ的二维射流床中，采用多路毕托管测试系统，对包括三种双组份混合物在内的五种物料的射流深度进行了考察。结果表明，射流管径、射流气速对射流深度都有影响，本文尤其考察了环隙气量与射流深度的关系，发现在同样的射流气速下，环隙气速增大则射流深度降低，得出了综合各种影响因素的关联式。     

超低浓度甲烷在Cu/γ-Al2O3催化颗粒流化床中的燃烧特性

采用流化床燃烧技术,使用自制Cu/γ-Al₂O₃颗粒作为催化剂床料,实验研究了超低浓度甲烷在流化床中催化燃烧时床层温度(450~700℃)、流化风速比ω(1.5~4)、进气甲烷体积分数(0.3%~2%)等对甲烷燃烧效率的影响。结果表明,床层温度是影响甲烷催化燃烧反应的关键因素,甲烷的转化率随着床层温度的升高而增加;床层温度达到650℃时,甲烷含量低于1%的超低浓度甲烷其转化率超过95%,继续提高床层温度至700℃且控制流化风速比ω≤2可以实现甲烷的完全转化;甲烷转化率随着流化风速和进气甲烷浓度的增加而降低,当ω>3.5时,温度对甲烷转化的影响减弱,未燃烧的甲烷含量增大。动力学实验发现,床层温度较低时,催化反应受动力学控制,测得催化反应的活化能E_a为1.26×10⁵J/mol,反应级数m为0.73,当温度t>450℃时,扩散作用影响显著,反应级数增大。     

悬浮床加氢裂化水溶性催化剂的筛选与表征

催化加氢作用, 当金属组分A和组分B浓度分别为 15 μg/g ～ 25 μg/g 和 1100 μg/g～1300 μg/g时催化剂具有较好的催化加氢活性。两元水溶性催化剂硫化后的XPS、XRD和TEM分析结果表明：活性组分经硫化反应后生成了金属硫化物,但组分A硫化率不足50％;组分B易硫化结晶,其晶粒成为组分A的硫化物晶粒或颗粒分散的“载体”,使组分A的硫化物具有较高的分散度,提高了催化剂的加氢活性;A-B双金属水溶性催化剂经硫化反应后所形成的颗粒尺寸在100 nm左右,说明两元金属催化剂在硫化结晶过程中确实存在相互分散和抑制晶粒增长的作用。     

TS-1分子筛对固定床中苯酚羟基化反应的催化性能

 制备了用于固定床反应器的负载型TS－1分子筛催化剂,并以苯酚羟基化为探针反应,研究了载体、钛含量和预处理剂等对负载型TS－1分子筛催化性能的影响,考察了固定床反应器中苯酚羟基化反应的工艺条件．结果表明,酸性较强的载体会加剧H2O2的分解,导致苯酚的转化率和H2O2的有效利用率下降;在所研究的ZSM－5,TiO2,Al2O3,ZrO2,SiO2和硅藻土载体中,硅藻土具有最好的催化性能;催化剂的活性与骨架钛含量有关;用HNO3,KAc,NaAc,NH4Ac和NH4Cl处理过的催化剂,活性和选择性得到提高,而用NH3·H2O,Na2CO3和Na3PO4等碱性物质处理后,催化剂的活性则下降;溶剂、反应温度、原料空速和苯酚／H2O2摩尔比对苯酚羟基化反应有很大影响．以丙酮为溶剂,在苯酚／H2O2摩尔比为3,反应温度为84℃,WHSV为8．46h－1的反应条件下,苯酚转化率、H2O2转化率、苯二酚选择性以及H2O2的有效利用率可分别达到27．7％,94．8％,97．7％和75．1％．