Treatment of pulp mill and oil sands industrial wastewaters by the partial spray freezing process

The spray freezing process, a natural freezing technology, was used to treat pulp mill effluent and oil sands tailings pond water. The wastewaters froze partially or completely (i.e. with or without runoff generation) during the spraying operation. Greater than 60% impurity reduction in the spray ice was obtained when 30% of the total volume of the sprayed water was released as runoff. Organic and inorganic contaminants were rejected with different efficiencies. The impurities were uniformly distributed within the ice columns when the spray ice was produced without generating any runoff. While a significant increase in impurity concentration was observed at the bottom of the ice formed with runoff production. The spray freezing process is an effective and economically feasible technique for wastewater treatment in cold regions. To achieve higher impurity removal efficiency, the wastewater should be only partially frozen during spray ice production.  

注浆技术在杂填土中的应用

介绍了注浆技术在杂填土中的施工方案及技术要求，同时阐述了施工质量的控制。  

车用LPG有害杂质的鉴别与脱除

采用12种普通液化石油气进行行车试验，发现汽车的燃气器具内积聚粉末或碎屑，严重时造成蒸发器或电磁阀堵塞；蒸发器腔体内生成粘稠状液体；含水LPG冬季结冰可造成供气系统堵塞。检验证明：粉末的主要成分是单质硫；碎屑是金属腐蚀的硫化物；粘稠状液体是多硫化物或丁二烯低聚体或重质烃类；上述生成物与LPG中的丙烯、丁烯的存在及其含量无关。严格控制普通LPG来料中的丁二烯含量(摩尔分数不超过0．5％)和重烃含量(每100ml气样LPG的蒸发残留物不超过0．05ml)，且采用常温、液相吸附工艺对普通LPG进行精制，即可获得满足用户要求的车用LPG。在5000辆LPG汽车上应用获得成功。  

Influence of impurity ions and magnetic field on the properties of freshly precipitated calcium carbonate

Static magnetic field (MF) effects on the properties of freshly precipitated calcium carbonate have been investigated in the presence of impurity ion Mg(2+), Fe(2+), or SO4(2-). One or both solutions, CaCl2 and Na2CO3, were exposure to MF (0.5T) for 20min at 20 degrees C. Then calcium carbonate was precipitated and zeta potential, pH and light absorbance (lambda=543.3 nm) were measured. The same parameters were also determined for the reference systems in which the solutions were not MF-treated. It was found that in all the systems tested MF effects as determined by the above mentioned parameters had appeared. They depended on the kind of the impurity ion present, as well as on which solution, CaCl2, Na2CO3 or both, MF interacted. For example, if Mg(2+) ion was present in CaCl2 solution, the largest shift in the zeta potential toward higher positive values was observed if Na2CO3 was MF-treated (e.g. from 2 to 12mV) and the same was true as for the maximum in the light absorbance and the pH increase. Interestingly, if (CaCl2 + Mg(2+)) was MF-treated pH of the slurry had decreased. Moreover, a correlation between above mentioned MF effects and the entropy of hydration of the ions has also been found. This points to the changes in the hydrating water structure caused by magnetic field.  

原子吸收分光光度法测定氧化锌电阻片造粒料中杂质含量

为了加强工艺质量控制,使用原子吸收分光光度法对氧化锌电阻片造粒料中杂质含量进行测定,可以了解氧化锌电阻片中杂质元素的分布情况,通过对氧化锌电阻片电性能的跟踪分析,可以得出不同杂质含量对氧化锌电阻片电性能的影响,从而也验证了我们选取杂质元素在氧化锌造粒料中的含量上限的科学性。该方法手段先进,操作方便,具有广泛推广使用的价值。  

气水反冲洗滤池滤料底部杂物积聚的处理

就月浦水厂气水反冲洗滤池的滤料底部出现杂物积聚问题,分析了杂物积聚的原因,认为可采取增设细格栅、加强生产管理、严格把好滤料质量关、合理设置承托层的办法加以解决.  

防止第一换热器堵塞的技改方案

原工艺过程中酚水洗涤煤气所产生的杂质导致第一换热器堵塞，通过技改，采用旋风除尘装置工艺，解决粗煤气中的杂质，从而达到保护催化剂的作用。  

PT燃油系统常见故障与排除

介绍了PT燃油系统的组成及功用,结合工作实践中接触到的几类常见故障,对其故障的危害及其原因进行了分析,并详细介绍了故障排除方法,可为该系统的维护保养提供有益的参考和借鉴。  

气水反冲洗滤池滤料底部杂物积聚的处理

就月浦水厂气水反冲洗滤池的滤料底部出现杂物积聚问题,分析了杂物积聚的原因,认为可采取增设细格栅、加强生产管理、严格把好滤料质量关、合理设置承托层的办法加以解决.  

杂种·纯种--两个建筑师在京师大厦竣工后的对话

通过两位建筑师茶室中的对话,阐明建筑活动是一项社会活动,建筑的纯粹和混杂具有一定的相对性.