高速射流淹没冲撞消能的数值模拟研究

爆破膜装置在现代水电站建设中,特别是中小型水电站中得到广泛的应用。但当爆破膜爆破后,高速水流对尾水渠产生巨大的冲刷,如何有效解决高速水流消能成为爆破膜设计中的关键问题。本文通过在压力管道末端设置消能池,并采用单股水流淹没冲撞消能的方式,使高速水流通过淹没射流的方法安全泄流消能,并通过数值模拟的方法证明其有效性。     

废弃电路板非金属粉末粒径对水泥砂浆性能的影响

将废弃电路板回收处理后得到的非金属粉末掺入水泥砂浆中,研究非金属粉末粒径大小对水泥砂浆性能的影响;为改善非金属粉末和水泥浆体之间的界面性能进而改善复合砂浆的性能,采用硅烷偶联剂处理非金属粉末和在砂浆中加入丁苯乳液2种改性方法.结果表明：硅烷偶联剂处理可以降低砂浆的含气量和收缩率,加入丁苯乳液改善了砂浆的抗压强度和毛细孔吸水率.偶联剂处理和加入丁苯乳液都可以提高砂浆的抗折强度和黏结抗拉强度.废弃电路板非金属粉末粒径越小,水泥砂浆的抗压强度、抗折强度和黏结抗拉强度越大,含气量、收缩率和毛细孔吸水率越小.     

水化普通硅酸盐水泥颗粒吸附水中磷酸盐研究

以水化普通硅酸盐水泥颗粒为吸附剂,研究了时间、温度和粒径等因素对其吸附PO3-4效果的影响.结果表明:在20℃,粒径0.5~1.0mm,初始PO3-4质量浓度100mg/L条件下,水化普通硅酸盐水泥颗粒吸附平衡时间为192h,平衡吸附量高达16.06mg/g;经0.25mol/L盐酸活化后,水化水泥颗粒对PO3-4的平衡吸附量增至18.54mg/g;粒径2.0~3.0mm的颗粒对PO3-4的吸附效果优于0.5~1.0mm和5.0~60mm的颗粒.吸附过程遵循假二级动力学模型,符合Freundlich等温方程.热力学解析的结果表明:酸活化水化水泥颗粒吸附PO3-4时焓变ΔH=7.56kJ/mol,熵变ΔS=0.0416kJ/（mol·K）;4,20℃的吉布斯自由能ΔG分别为-3.98,-4.65kJ/mol;酸活化水化水泥颗粒对PO3-4的吸附是一个以吸热、化学吸附为主,熵推动且自发的过程.     

Optimizations and heat integrations on the separation of toluene and 1-butanol azeotropic mixture by pressure swing distillation

In this study, optimizations on separation of Toluene and 1-Butanol mixture is carried out by pressure swing distillation process. New heat integration methods are applied and compared to conventional PSD process by using vapor recompression technique combined with pressure swing distillation process. New heat integration methods show positive results to decrease the utilities used in the process. A simulator Aspen HYSYS V8.4 is used for simulating all processes. Cost analysis is also performed and Aspen HYSYS V8.4 optimizer program is used for optimizing profit for the process. Pressure is also optimized for minimum heat duty requirements in the process and the ultimate concern is to minimize the total reboiler heat duties and overall operating cost for the system which results into increasing profit.     

L-cystein modified bentonite-cellulose nanocomposite (cellu/cys-bent) for adsorption of Cu2+, Pb2+, and Cd2+ ions from aqueous solution

In this study, L-cystein modified bentonite-cellulose (cellu/cys-bent) nanocomposite was synthesized and characterized by XRD, FTIR, SEM with EDS, TGA, and TEM techniques. In order to optimize the process the effect of various operational parameters such as pH, adsorbent dosage, contact time, and temperature were also investigated. The adsorption experiments were carried out in initial concentrations range of 20-100 mg L^?1and the adsorbent affinity for metal ions was found to be in order of Cu²⁺ > Pb²⁺ > Cd²⁺. The optimum pH for adsorption of Cu²⁺ and Cd²⁺ was observed at 5 while for Pb²⁺ it was pH 6. Based on the Langmuir model, the maximum adsorption capacity of Cu²⁺, Pb²⁺, and Cd²⁺ at 50^?C was found to be 32.36, 18.52, and 16.12 mg g^?1, respectively. The Langmuir isotherm and pseudo-second order model were found to be better fitted than the other isotherms and kinetic models. The results of thermodynamic parameters confirmed the process to be endothermic and spontaneous in nature.     

Separation of Ru(III), Rh(III) and Pd(II) from nitric acid solutions using ion-exchange resins bearing carboxylic betaine

To understand the adsorption properties of a styrene–divinylbenzene copolymer functionalized with N,N,N-trimethylglycine, AMP03, the adsorption behaviours for platinoid ions (Ru(III), Rh(III) and Pd(II)) were examined. Furthermore, we performed adsorption experiments using sample solutions by adding triethylamine, thiourea and N,N,N-trimethylglycine. Based on the adsorption data obtained in this study, we performed chromatographic experiments. The results indicated that all platinoid ions in the feed solution completely adsorbed on AMP03, and almost 80% of the adsorbed platinoid ions were recovered. These results show that AMP03 has the potential to recover Ru(III), Rh(III) and Pd(II) from high-level liquid waste.     

Adsorption of lead and copper on bentonite and grapeseed activated carbon in single- and binary-ion systems

In this study, bentonite originating from Turkey (Eski?ehir province) and activated carbon obtained from grapeseed were used as adsorbents for the removal of lead (Pb²⁺) and copper (Cu²⁺) ions from aqueous solutions. Experiments were performed in single- and binary-ion systems at constant temperature of 298 K and pH value of 5. In order to describe the adsorption mechanism Langmuir, Freundlich and Temkin isotherms were used. The total adsorption capacity values of adsorbents were compared. It was observed that the total adsorption capacity values were changed depending on the type of adsorbent used, type of metal ion and interaction between metal ions.     

Purification of coal mine methane on carbon molecular sieve by vacuum pressure swing adsorption

The vacuum pressure swing adsorption (VPSA) method, as an alternative way to separate the CH₄/N₂ mixture, was adopted to purify methane from coal mine methane. The performance of the VPSA process was investigated experimentally and theoretically with a reactivated carbon molecule sieve as the adsorbent. The computer calculations were compared to the experimental data. The concentrated methane with 79% purity could be collected directly during the high-pressure adsorption step with 93% recovery and 0.0720 mL·g^–1·min^–1 productivity, when the composition of raw gas was 10/90 vol% CH₄/N₂, which is of great significance for the utility of low quality energy gas.     

Synthesis and application of phenylcarbamodithioate compound for steel protection

Phenyldithiocarbamate compound has been synthesized and studied as corrosion inhibitor for steel. Dithiocarbamate (DTC) compounds with linear alkyl groups are good inhibitors, but their stability is quite low in acidic solutions. It should be noted that long-term stability is important for practical applications, in order to avoid excess use of chemicals. So, we have synthesized phenyl substituted DTC which offers strong inhibition efficiency and extra stability. This new inhibitor is chemically adsorbed on steel through its DTC group, while the aromatic ring provides extra stability and long-term efficiency. For the assessment of corrosion kinetics, we have utilized potentiodynamic and ac impedance studies; also solution assay analysis was realized with atomic absorption spectroscopy. It was revealed that inhibitor exhibits remarkably high efficiency, even under elevated temperature conditions. At 55 °C temperature conditions, i_corr value decreased from 5050 to 154 μA cm^?2, with the addition of 500 ppm inhibitor. The long-term stability of inhibitor was also tested and 85.93% efficiency was obtained after three days of exposure period for 500 ppm concentration.     

交联壳聚糖凝胶溶胀性能及Ni(Ⅱ)吸附效果研究

以壳聚糖为原料,戊二醛为交联剂制备交联壳聚糖凝胶,并对凝胶的溶胀性能及Ni~(2+)吸附效果进行研究。实验结果表明,交联剂用量越大,交联密度越高,但是凝胶网络弹性降低,溶胀性变差;弱酸至中性条件有利于凝胶的溶胀,交联改性能降低壳聚糖的溶胀热敏温度,降低后期吸附Ni~(2+)的能耗。用1%的戊二醛交联壳聚糖处理20、40 mg/L Ni~(2+)电镀废水,投加60 mg交联改性壳聚糖,在30℃、p H=7条件下吸附3 h,吸附率分别达96.9%和92.4%,吸附过程可用一级动力学模型进行模拟。废水经过二次吸附后出水水质均能达到0.01 mg/L Ni~(2+)的《污水综合排放标准》(GB3838)标准,交联改性壳聚糖的重复使用性好,多次循环使用后依然具有很好的吸附效果。