地沟油水解法基于浮选的再生技术研究*

本文选择食堂废弃的地沟油为研究对象,通过控制水解条件,获得不同性质的地沟油改性捕收剂。分别探究温度、催化剂、乳化剂用量等因素对地沟油水解的影响规律,确定其最佳的改性条件。采用接触角测定表征地沟油的改性效果,通过比较地沟油改性捕收剂在固废浮选方面的应用效果。结果表明地沟油改性剂具有一定的捕收作用,在浮选分离领域,可替代传统脂肪酸类捕收剂及非极性烃类捕收剂的使用。     

The effect of zinc cyanide on the flotation of gold from pyritic ore

In gold processing plants, the process water contains a considerable amount of weak acid dissociable (WAD) cyanide species. The cyanide-containing water recycled to flotation circuits has a deleterious effect on mineral flotation. Zinc cyanide can be a major constituent of the process water due to the cyanide leaching of zinc minerals and the zinc cementation applied to precipitate gold and silver. In the present study, the effect of zinc cyanide on the flotation of gold from a pyritic ore was evaluated and the competitive adsorption between zinc cyanide species and the collector, potassium amyl xanthate (PAX) or Aerophine promoter (3418A), on gold was studied by surface enhanced Raman spectroscopy (SERS). It was found that free cyanide did not depress the flotation of liberated gold, but zinc cyanide with a CN/Zn ratio of 2 did. The depression of gold flotation by zinc cyanide was due to the preferential adsorption of Zn(CN)₂ on gold surface over either 3418A or amyl xanthate in the solution, rendering gold surface hydrophilic.     

746MW汽轮发电机集电环过热打火缺陷分析

集电环是发电机励磁系统的重要部件,通以大电流并随着转子高速旋转,通过对一起汽轮发电机励磁集电环早期故障分析,并结合现场实际情况,给出了故障发现、分析和处理方法.     

Transparent Insulation System for Passive Solar Energy Utilization in Buildings

A new concept for the passive use of solar energy, transparent insulation, is described together with the first experimental results. Transparent insulation material has the property of being transparent or translucent to solar radiation while at the same time acting as heat insulation, Elements made of this material can be attached to the walls of buildings and thus permit the utilization of solar energy for heating. Relations are given for the dependence of heat flux and conversion efficiency of radiation into useful heat on the thermal resistance of the components. Calculations using meteorological data show that with materials parameters achievable with present technology not only south but also west/east and possibly even north orientations can lead to significant contributions to heating. In order to avoid overheating in summer, control of radiation must be provided.

Experiments with unoptimized materials on two buildings during 1982/83 showed promising results: for a south facade during a Sunny period in January, a mean flux of 9 W/m² into the house was observed. For the entire heating season the extrapolated value is 16 W/m². On a western orientation a net loss was observed, but the mean effective heat transfer coefficient of the element was lowered from 1.8 W/m²K without radiation to 0.25 W/m²K with radiation. The beneficial effect of masonry walls with regard to heat storage and damping of temperature fluctuation was also demonstrated. The elements proposed here therefore appear particularly attractive for retrofitting.     

Computational simulation of adsorption and thermodynamic study of xanthate,dithiophosphate and dithiocarbamate on galena and pyrite surfaces

Computer modeling and the microcalorimetry method were employed to investigate the adsorption of xanthate, dithiophosphate (DTP) and dithiocarbamate (DTC) on the galena and pyrite surfaces. The calculated results show that the pyrite surface undergoes greater relaxation than galena, while galena has a more electronegative surface than pyrite. The pyrite Fe atom is more active than the galena Pb atom. The simulations of adsorption show that the adsorbates coordinate mainly to the surfaces through interaction between their S atoms with the surface Pb or Fe atoms. The analysis of the density of states (DOSs) suggests that the adsorption of xanthate on the pyrite surface is stronger than that on the galena surface, while that of DTP and DTC are stronger on the galena surface than on the pyrite surface.The heat of adsorption and kinetics parameters of DTC and DTP at the galena and pyrite surfaces differ greatly, suggesting that DTC and DTP exhibit good selectivity in the separation of pyrite and galena, while these two parameters for xanthate at the two minerals differ little, indicating the poor selectivity of xanthate.     

Heterogeneous photocatalytic hydrogen generation in a solar pilot plant

Few studies have been published about large scale heterogeneous photocatalysis hydrogen generation with simultaneous removal of organic pollutants. The purpose of the present work was to study the simultaneous photocatalytic hydrogen production and organic pollutant removal under direct solar irradiation at pilot-plant scale. The experiments were performed in a Compound Parabolic Collector (CPC) at the Plataforma Solar de Almería (PSA). The efficiencies of two different photocatalytic systems, one based on a nitrogen doped and platinized TiO₂, and the other using a platinized CdS–ZnS composite were evaluated. Formic acid and glycerol were used as sacrificial electron donors. Also, experiments using real municipal wastewaters were carried out showing simultaneous hydrogen generation and partial water pollutant removal. The largest amounts of hydrogen were obtained with aqueous solutions of formic acid, although the experiments with real wastewater gave moderate amounts of hydrogen, pointing towards the possible future use of such waters for photocatalytic hydrogen generation.     

用电负性原理定量计算捕收剂非极性基长度的意义及应用

论述了采用电负性原理对捕收剂的非极性基长度进行定量计算的原理和方法 ,为利用捕收剂的非极性基长度提高捕收剂的选择性提供了理论基础 ,并列举了实际浮选试验结果 ,论证理论计算的正确性及实际应用意义 ,同时也指出了存在的问题     

深海集矿技术的评价

国外在深海多金属结核开采技术研究这一领域中开展研究工作历时20余年,取得了许多成果。本文简要评价了国外在深海采矿系中的集矿技术的研究成果,分析集矿技术研究及集矿机研制所面临的问题。在此基础上,结合我国国情,提出了采用自行装置的复合式集矿机研制方案。     

N—羟基邻苯二甲酰亚胺与萘羟肟酸对氟碳铈矿的浮选性能研究

通过对氟碳铈矿纯矿物和实际矿石的浮选试验以及吸附量测定的研究，阐述了Ｎ－羟基邻苯二甲酰亚胺和萘羟肟酸对氟碳铈矿的浮选性能。结果表明，它们对氟碳铈矿均具有良好的浮选选择性。两者相比，Ｎ－羟基邻苯二甲酰亚胺的浮选选择性好，而萘羟肟酸的浮选捕收能力强。     

阴离子捕收剂LKY试验室试验及工业试验研究

本文以阴离子捕收剂LKY试验室试验及工业试验的结果并与RA-315对比，表明LKY阴离子捕收剂的性能和选别效果都优于RA-315，完全可能取代RA-315药剂。为选矿药剂的开发提供了前景。