R&D and Application of Catalyst for Resid Hydrotreating in Upflow Reactor

In order to extend the operating cycle of the upflow reactor for resid hydrotreating, the Re- search Institute of Petroleum Processing taking into account the specifics of resid hydrotreating upflow reactor has developed the high-performance RUF series of catalysts suitable for operation in the upflow reactor. The results of commercial application of catalysts revealed that this RUF series of catalysts loaded after optimized grading could effectively remove metals, sulfur and carbon residue from the re-sidu...     

Improving biohydrogen production in a carrier-induced granular sludge bed by altering physical configuration and agitation pattern of the bioreactor

Our newly developed carrier-induced granular sludge bed (CIGSB) bioreactor was shown to be very effective in hydrogen production. However, since mechanical agitation was not employed to enable sludge granulation, the CIGSB system might encounter problems with poor mass transfer efficiency during prolonged operations. This work was undertaken to improve mixing efficiency of CIGSB for better biomass-substrate contact by adjusting the height to diameter (H/D) ratios of the reactor and by implementing appropriate agitation device. Three H/D ratios (4, 8, and 12) resulting in liquid upflow velocities (v_up) of 0.057–1.32 m/h were examined as the CIGSB reactor was carried out at a descending hydraulic retention time (HRT) from 4 to 0.5 h. The results show that decreasing HRT resulted in increases in the H₂ production rate, regardless of the H/D ratios. Reactors with a H/D ratio of 8 gave better H₂ production performance with a H₂ production rate of 6.87 l/h/l and a H₂ yield of 3.88 mol H₂/mol sucrose, suggesting that the effectiveness of H₂ production in the CIGSB system can be enhanced by using a proper v_up and physical configuration of the reactor. Supply of additional mechanical agitation for CIGSB reactor (H/D=12) alleviated the phenomena of sludge piston floatation, leading to further increases in the H₂ production rate and H₂ yield to 9.31 l/h/l and 4.02 mol H₂/mol sucrose, respectively. The major soluble metabolite was butyric acid, followed by acetic acid, propionic acid, and ethanol. The former two accounted for nearly 67–76% of total soluble microbial products, indicating the presence of favorable pathways in the CIGSB culture from the aspect of H₂-producing metabolism.     

Process kinetics of UASB reactors treating non‐inhibitory substrate

The degradation of a non‐inhibitory substrate (sucrose) in upflow anaerobic sludge bed (UASB) reactors with different superficial flow velocites (u_s) was performed to generate experimental data. Additionally, a kinetic model accounting for the mass fraction of methanogens (f) and granule size distribution in UASB reactors is also proposed. At the volumetric loadings of 2.65–21.16 g COD dm^?3 day^?1, both the COD removal efficiency and granule size of the UASB reactors increase with increasing u_s. The f values determined experimentally increase from 0.13–0.24 to 0.27–0.43 if the volumetric loading is increased from 2.65 to 5.29 g COD dm^?3 day^?1. With a further increase in volumetric loading, the f values decline because of the accumulation of volatile fatty acids (VFAs). The predicted residual concentrations of VFAs and COD are in fairly good agreement with the experimental data. From the calculated effectiveness‐factor values, the influence of mass transfer resistance of the substrate sucrose on the overall substrate removal rate should not be neglected. From parametric sensitivity analyses together with the simulated concentration profiles, methanogenesis is the rate‐limiting step. Copyright © 2003 Society of Chemical Industry     

Hydration of 2-methyl-2-butene in gas-liquid cocurrent upflow and downflow reactors

An olefin (2-methyl-2-butene) gas and distilled water were fed either upwardly or downwardly into a fixed-bed reactor packed with strong acidic ion-exchange resins. Global reaction rates of olefin hydration were measured by changing gas and liquid velocities. The observed rates were interpreted by using a model in which the direct mass transfer from gas to solid occurred as well as the indirect mass transfer through the liquid phase.     

Anaerobic treatment of wastewater containing fatty acids in upflow reactors

An extended summary is presented of a Dr.Sc. Thesis in which the results of a study on anaerobic treatment of wastewater containing fatty acids have been reported. This study, concerning the technological features of this process in upflow reactors, was aimed at the following subjects :

• - the dynamics of the fluid flow in the reactor;

• - the dynamic behaviour of the sludge particles in the reactor;

• - the kinetics of the conversion of the fatty acids and of the formation of the products (mainly biogas and anaerobic sludge); and

• - the separation of the gas and the sludge from the treated water.

From the results obtained in experiments on lab-scale and (semi) technical scale, a quantitative model for the operation of the reactor has been derived. This model can be used for scaling-up purposes and for optimisation of the process performance.     

厌氧-好氧组合工艺处理制药废水的试验研究

采用上流式厌氧污泥床反应器-移动床生物膜反应器串联装置,处理含有大量氨基酸和皂素的制药废水。系统的总COD去除率平均在86%左右。当厌氧反应器的COD容积负荷为10～21kg/(m3·d),COD去除率平均为70%左右;好氧反应器的COD容积负荷率为2.48～2.87kg/(m3·d),COD去除率为59%。     

两段厌氧工艺处理含硫酸盐、氨氮废水的研究

将两段UASB反应器用于处理含高浓度硫酸盐、氨氮的有机废水,结果表明CODCr的去除率>95%,总磷的去除率>55%。第1段反应器进水的CODCr、硫酸盐、氨氮分别在11000、2800、1000mg/L时,硫酸盐、CODCr去除率分别为>96%、>87%;厌氧生物处理过程中,废水中的游离NH3与产生的H2S、VFA、CO2相互作用,有利于厌氧生物处理的顺利进行。第2段反应器进水pH7.7～7.8,出水pH>8.0,CODCr去除率为65%～75%。扫描电镜照片显示,两段反应器中占优势的微生物种群不同。     

水解酸化-厌氧-好氧工艺处理抗生素废水

试验采用生化工艺处理高浓度抗生素废水。结果表明 ,水解酸化反应器最大COD容积负荷达到 1 6.84kg/(m3·d)。厌氧复合床处理水解酸化后的抗生素废水 ,当容积负荷为 6.0kg/(m3·d)时 ,反应器对SS、COD、BOD5 的去除率分别为 75.6%、91 .7%、96.1 % ;厌氧出水采用周期循环活性污泥系统进行处理 ,当容积负荷为 1 .6kg/(m3·d)时 ,反应器对SS、COD、BOD5 的去除率分别为 91 .6%、88.7%、95.4%。     

Process intensification of gas–liquid downflow and upflow packed beds by a new low‐shear rotating reactor concept

In the present work, a new low‐shear rotating reactor concept was introduced for process intensification of heterogeneous catalytic reactions in cocurrent gas–liquid downflow and upflow packed‐bed reactors. To properly assess potential advantages of this new reactor concept, exhaustive hydrodynamic experiments were carried out using embedded low‐intrusive wire mesh sensors. The effect of the rotational velocity on liquid flow patterns in the bed cross‐section, liquid saturation, pressure drop, and regime transition was investigated. Furthermore, liquid residence time and Péclet number estimated by a stimulus‐response technique and a macro‐mixing model were presented and discussed with respect to the prevailing flow patterns. The results revealed that the column rotation induces different flow patterns in the cross‐section of the packed bed operating in a concurrent downflow or upflow mode. Moreover, the new reactor concept exhibits a more flexible adjustment of pressure drop, liquid saturation, liquid residence time, and back‐mixing at constant flow rates. © 2016 American Institute of Chemical Engineers AIChE J, 63: 283–294, 2017     

组合式厌氧滤池(UBF)处理柠檬酸生产废水

在用厌氧法处理柠檬酸生产过程中产生的pH值低(3~5)、含盐量高(Cl-=3000~5000mg/L)的离子交换废水时,遇到颗粒污泥很难形成的问题。为了解决此问题,设计和建设了4座直径为12m、高为23m、体积为2500m3的大型组合厌氧滤池(UBF)。经过近2年的启动和实际运行,在容积负荷为3~4kgCOD/(m3·d)、不用碱性物质调节pH值的条件下,对COD的去除率>75%,出水SS<200mg/L,污泥量缓慢增加,未出现堵塞现象。