卤水净化气液连续反应器研究

根据对文丘里射流器工作原理和性能的研究,设计制作处理量为5m~3/h的卤水净化气液连续反应器。该反应器可使烟气和卤水连续混合反应去除Ca~(2+),具有较大的气液比,同时具有较好的气液混合效率,工作压力在0.40~0.45MPa范围能满足卤水净化工艺在气液反应过程单元对Ca~(2+)去除率(达到60%)的要求。     

喷射自吸式生化反应器气液传质的研究

<正> 一、前言 从宏观分析,生化反应器是非均质的包含物理传质过程的催化反应器,其催化剂为有生命活性的微生物菌体或酶。从微观概念出发,每一个微生物活细胞本身就是一个微型反应器。维持反应系统的气(氧)-液(水和营养基质、代谢产物)-固(微生物菌体)三相良好的混合与分散,尤其是较高的溶氧传质速率,是需氧生化反应器设计和放大的关键。在生化工程领域,通常以体积溶氧系数K_La和溶氧比能耗(P_W/V_L)/OTR表征气液传质效能。 我们在上文已介绍了喷射自吸式反应器的喷射吸气特性,并推导出吸气速率的数学表达式;本研究对喷射自吸式反应器的另一个重要特性——气液传质性能及其与反应器喷射     

单泵多喷嘴并联尿素喷射系统实验研究

目前国内外单喷嘴单泵尿素喷射系统已在市场上有广泛的应用,但是单喷嘴单泵的系统不足以满足大功率柴油发动机的后处理还原需求。文章对单泵多喷嘴并联尿素喷射系统进行了实验研究。基于SCR对喷射性能的要求,对单泵多喷嘴的各个喷嘴喷雾性能进行测试,结果表明,单泵多喷嘴的各个喷嘴性能一致且能满足要求。该研究为大功率发动机的后处理系统提供了一种结构布置简单并且成本较低的方案。     

喷孔锥度对喷气织机环槽型辅助喷嘴性能的影响

为提升引纬质量,课题组设计了一种环形槽型喷孔辅助喷嘴,并通过数值模拟探究辅助喷嘴结构对喷射性能的影响。课题组依据喷射出口面积等效原则,设计了3种环槽型辅助喷嘴,并分别建立了环形槽结合中心式辅助喷嘴的流场模型;利用FLUENT软件对建立的流场模型进行数值模拟,得到供气压力0.3 MPa时不同喷孔锥度的各环槽型辅助喷嘴对称面上速度云图、出口流速中心线上速度分布曲线图、气耗量,以及距喷嘴出口20,50,70 mm处截面速度分布图。结果表明：对同种环槽型辅助喷嘴,随着喷孔锥度增大,辅助喷嘴的喷射性能明显增强;喷孔锥度大于0°时,喷孔锥度增大各喷嘴出口处射流速度也随之增大。环槽型辅助喷嘴为喷气织机引纬提供了一种效率更高的方法。     

多相喷嘴微观混合特性的研究

微观混合的研究对于更好地认识和处理一些受其影响的快速反应过程(聚合、结晶等)具有重要的指导意义。设计了一种作为反应器的多相喷嘴,同时采用经典的KI-KIO3平行竞争反应体系来研究其微观混合特性,考察了该多相雾化喷嘴在各种操作条件对微观混合的情况,探寻不同条件下微观混合效果的变化规律。结果表明,增大雾化气量或减小进液量,提高气液质量比,可显著改善多相雾化喷嘴的微观混合效果。减小进料流量比α(=VA/VB)可以增强微观混合效果。总结了各操作参数对微观混合的影响。     

螺旋藻溢流喷射光生物反应器及其放大设计

介绍了已获国家专利（专利号：９６２１６３６４３）的８Ｌ螺旋藻溢流喷射光生物反应器的基本结构与特点，并采用光照比表面积和单位体积藻液吸气量相等的原则对其进行了放大设计。放大后的反应器容积为１００Ｌ，光照比表面积２２２ｍ２／ｍ３，循环藻液量１０８０Ｌ／ｈ，吸气量１５０Ｌ／ｈ，基本保持了８Ｌ反应器的优点。但藻液循环系统尚需进一步改进     

国内外喷气织机主喷嘴喷射特性的测试与分析

通过对进口日本津田驹ZAX-e型主喷嘴与国产主喷嘴的喷射性能进行对比测试与分析,指出进口主喷嘴的喷射性能优于国产主喷嘴,并分析了两者存在差距的原因。     

喷射自吸式生化反应器喷射吸气的研究

<正> 一、前言 四十多年前,Mertes发现了射流现象可应用于气液混合与反应,开拓了喷射反应器在化学工程领域的应用。近十多年来,生化工程领域出现了一种新型的喷射通气生化反应器,具有优良的传质传热性能,能耗低,可省去空压机及附属设备,结构大型化等优点。但是在国内,这种新型反应器除在污水生化处理中开始研究应用外,在发酵工业上尚属空白。因而,研究和开发这种新型生化反应器,无疑对我国生化工程尤其是发酵工业具有重要的现实意义。     

QHJ—3000型饮料自动混合机气—液混合器的研究

本文简要论述了QHJ-3000型全自动饮料混合机的技术原理与设计特点,着重分析并研究了喷射式气—液混合器的工作状况,提出了定量计算喷射式气—液混合装置混合效果的数学模型——喷射混合紊流方程组及其封闭求解条件,为进一步改进喷射型饮料混合机性能提供了理论依据。     

第一喷嘴结构参数对喷气纱强力的影响

喷气纺纱机上第一喷嘴的结构参数主要包括喷射孔角度、喷射孔直径和喷射孔数目,为说明各主要结构参数对喷气纱强力的影响,通过试验和回归分析的方法探讨了第一喷嘴各结构参数对喷气纱强力的影响。最终得到的结论是第一喷嘴的结构参数对喷气纱强力有较大影响,当喷射孔角度为42.9°,喷射孔直径为0.4 mm,喷射孔数目为4个时,成纱强力最高。     

Nitrogen removal from wastewater using simultaneous nitrate reduction and anaerobic ammonium oxidation in single reactor

The effects of C/N ratio and total organic carbon (TOC) loading on nitrogen removal through simultaneous nitrate reduction and anaerobic ammonium oxidation in a single reactor were examined. Granular sludge taken from a methane fermentation reactor was placed in an upflow reactor and supplied with synthetic wastewater containing nitrate at a C/N ratio of 1 to grow heterotrophic denitrifying bacteria. When nitrogen removal ratio reached 30%, anammox sludge attached to nonwoven-carrier was added into the same reactor and then ammonia was added to the synthetic wastewater. Nitrogen removal ratio was markedly increased to 80-94%. In this system, nitrogen removal ratio was affected by C/N ratio and TOC loading, not by the amount of granular sludge. A stable isotopic analysis using 15N-labeled nitrate showed that N2 gas was formed by anammox reaction.     

Simultaneous Desulfurization and Denitrification of Flue Gas by ·OH Radicals Produced from O(2)(+) and Water Vapor in a Duct

In the present study, simultaneous flue gas desulfurization and denitrification are achieved with ·OH radicals generated from O(2)(+) reacting with water vapor in a duct. The O(2)(+) ions are generated by a strong ionization dielectric barrier discharge and then injected into the duct. Compared with conventional gas discharge treatment, the present method does not need a plasma reaction reactor, additional catalysts, reductants, or oxidants. The main recovered products are the liquids H(2)SO(4) and HNO(3), which can be used in many processes. Removal rates of 97% for NO and 82% for SO(2) are obtained under the following optimal experimental conditions: molar ratio of reactive oxygen species (O(2)(+), O(3)) to SO(2) and NO, 5; inlet flue gas temperature, 65 °C; reaction time, 0.94 s; and H(2)O volume fraction, 8%. Production of O(2)(+) and the plasma reaction mechanisms are discussed, and the recovered acid is characterized. The experimental results show that the present method performs better for denitrification than for desulfurization. Compared with conventional air discharge flue gas treatments, the present method has lower initial investment and operating costs, and the equipment is more compact.     

Chemical looping combustion in a rotating bed reactor--finding optimal process conditions for prototype reactor

A lab-scale rotating bed reactor for chemical looping combustion has been designed, constructed, and tested using a CuO/Al(2)O(3) oxygen carrier and methane as fuel. Process parameters such as bed rotating frequency, gas flows, and reactor temperature have been varied to find optimal performance of the prototype reactor. Around 90% CH(4) conversion and >90% CO(2) capture efficiency based on converted methane have been obtained. Stable operation has been accomplished over several hours, and also--stable operation can be regained after intentionally running into unstable conditions. Relatively high gas velocities are used to avoid fully reduced oxygen carrier in part of the bed. Potential CO(2) purity obtained is in the range 30 to 65%--mostly due to air slippage from the air sector--which seems to be the major drawback of the prototype reactor design. Considering the prototype nature of the first version of the rotating reactor setup, it is believed that significant improvements can be made to further avoid gas mixing in future modified and up-scaled reactor versions.     

微波辅助提取香椿叶黄酮工艺的研究

比较微波辅助甲醇提取香椿黄酮与乙醇提取、甲醇回流和乙醇回流等工艺提取香椿黄酮的效果,用正交设计筛选微波辅助乙醇提取工艺条件,并探讨材料的液料比、体积分数、微波处理时间、微波功率对提取效果的影响,结果表明:微波辅助甲醇提取和乙醇提取效果明显优于其它传统方法;最佳工艺条件:液料比25 mL/g,乙醇体积分数70%,微波功率400 W,处理15 min。此工艺提取率达到70.15%,是一种高效、节能的提取香椿黄酮的工艺。     

影响酶法酯交换中甘二酯含量的因素研究

甘二酯是酶法酯交换过程中重要的中间体.较高的甘二酯含量影响最终产品的纯度,也导致副产物的产生.研究了酶法催化酯交换过程中反应温度、反应时间、水含量、酶用量、底物比对甘二酯含量的影响.实验结果表明,反应体系中酶量是影响甘二酯含量的最大影响因素,且为正相关.在符合产品结构的较优的反应中,甘三酯含量为88.2%,甘二酯含量为6.9%.     

木薯酒精废水厌氧可生化性实验研究

采用锥形瓶反应器对木薯酒精废水的厌氧可生化性进行了研究。在连续37d的实验中,COD从10865mg/L下降到1060mg/L,总去除率达90.24%。结果表明:木薯酒精废水的厌氧可生化性很好。反应前期VFA浓度迅速上升,在第9d达到最大值,为95.17mmol/L,随后,VFA浓度开始下降,产甲烷量迅速增加。反应达到稳定后,pH值维持在7.00～7.40之间,体系的缓冲能力较强。     

Hydrogen generation in microbial reverse-electrodialysis electrolysis cells using a heat-regenerated salt solution

Hydrogen gas can be electrochemically produced in microbial reverse-electrodialysis electrolysis cells (MRECs) using current derived from organic matter and salinity-gradient energy such as river water and seawater solutions. Here, it is shown that ammonium bicarbonate salts, which can be regenerated using low-temperature waste heat, can also produce sufficient voltage for hydrogen gas generation in an MREC. The maximum hydrogen production rate was 1.6 m(3) H(2)/m(3)·d, with a hydrogen yield of 3.4 mol H(2)/mol acetate at a salinity ratio of infinite. Energy recovery was 10% based on total energy applied with an energy efficiency of 22% based on the consumed energy in the reactor. The cathode overpotential was dependent on the catholyte (sodium bicarbonate) concentration, but not the salinity ratio, indicating high catholyte conductivity was essential for maximizing hydrogen production rates. The direction of the HC and LC flows (co- or counter-current) did not affect performance in terms of hydrogen gas volume, production rates, or stack voltages. These results show that the MREC can be successfully operated using ammonium bicarbonate salts that can be regenerated using conventional distillation technologies and waste heat making the MREC a useful method for hydrogen gas production from wastes.     

鼓泡式鱼类清洗机管路湍流数值模拟与优化

采用Fluent软件对鼓泡管路中的分流管内部流场进行数值模拟,选用标准k-ε湍流模型模拟分流管上每个喷气口气体的流速分布图,当分流管长为40cm时,每个喷气口气体的流速相近,产生的气泡均匀、可控。通过对分流管上的喷气孔径、孔距等相关参数进行数值模拟,使用Mixture多相流模型、扩展的标准k-ε湍流模型模拟不同气流速度对气体体积分数、湍流动能、湍流耗散率的影响。结果表明:气流流速与气体体积分数、湍流动能、湍流耗散率具有正相关性,当鼓泡管路中参考气流速度8m/s、喷气孔径6mm、喷气孔径间距70mm时,湍流动能转化比最高(67.7%)。验证实验表明:清洗时间、气流流量、清洗量对鲫鱼表面和腹腔的清洗效果影响显著,当清洗时间170s、气流流量145L/min、清洗量1.5kg时,清洗效果达92分。     

酶解花生壳制备低聚木糖的研究

以花生壳为原料,在固液比1∶20,H_2SO_4浓度为1.0%,120℃条件下处理30min,木聚糖提取率为40.1%。利用木聚糖酶降解木聚糖制备低聚木糖,确立了酶解工艺条件:50℃,pH4.8,加酶量2%(相对固体花生壳原料).搅拌速度80r/min,反应时间24h。在上述反应条件下,低聚木糖得率为81.2%。     

双菌固态发酵处理餐厨垃圾

利用固态发酵的方法对城市餐厨垃圾进行处理,制造富含菌体蛋白的饲料。研究中采用多种酵母菌和霉菌混合发酵,筛选出了(白地霉F-1,米曲霉F—6)为优势菌种组合,并考察了发酵条件,最优化结果为:对发酵培养基高温灭菌20 min,加入(NH_4)_2SO_4 1％,KH_2PO_4 4％,NaCl3％,初始pH 5.5,含水率60％左右;种子液15％,接种比例为1:1,发酵5d。最终得到的饲料粗蛋白含量为33.87％,比原料增加了6.85％。