制革废水的资源化处理技术

概述了我国制革工业废水现状,对制革废水资源化处理技术进行综述。认为将资源化处理技术与生产工艺紧密结合是解决制革废水污染的最佳途径。     

FULL CONTAINMENT SPRAY DRYING

ABSTRACT

Aspects of safety, environmental protection, and powder quality will continue to influence advances within spray dryer design and operation, and the concept of full containment spray drying offers a means to meet future industrial requirements. Process air recycle and powder containment within the drying chamber leads to no process air discharge to atmosphere, provides a more favorable operator environment around the spray dryer installation, reduces regions within the dryer layout where potential explosive powder/air mixtures can exist, improves yields, reduces powder losses, and provides easier cleaning operations with reduced wash water requirements.     

Steam Drying - Modelling and Applications

ABSTRACT

The concept of steam drying originates from the mid of the last century. However, a broad industrial acceptance of the technique has so far not taken place. The paper deals with modelling the steam drying process and applications of steam drying with in certain industrial sectors where the technique has been deemed to hove special opponunities.

In the modelling scction the mass and heat transfer proceases are described along with equilibrium, capillarity and sorption phenomena occurring in porous materials during the steam drying process. In addition existing models in the literslure are presented.

The applications discussed involve drying of fuels with high moisture contcna, cattle feed exemplified by sugar beet pulp. lumber. paper pulp. paper and sludges.

Steam drying is compared to flue gas drying of biofuels prior to combustion in a boiler. With reference to a current insrallation in Sweden. the exergy losses. as manifested by loss of co-generation cupacity. are discussed. The energy saving potentid when using steam drying of sugar beet pulp as compared to other possible plant configurations is demonstrated.

Mechanical vapour recompression applied to steam drying is analysed with reference to reponed dau from industriul plsnts. Finally. environmcntul advantages when using steam drying are presented.     

Strength Loss Mechanisms for Adhesive Bonds to Electroplated Zinc and Cold Rolled Steel Substrates Subjected to Moist Environments

Mechanisms of strength toss which affect the durability of epoxy adhesive bonds in moist environments were investigated for electroplated zinc and cold rolled steel substrates. Activation energies for adhesion loss, formation of corrosion product on the substrate surface, and moisture diffusion in the adhesive were determined experimentally. For cold rolled steel substrates, the activation energy for adhesion loss was identical, within experimental error, to the measured activation energy for moisture diffusion in the adhesive. Both of these values were substantially less (=40%) than the activation energy for formation of corrosion product. This confirms the previous results of Gledhill and Kinloch (J. Adhesion 6, 315 (1974)), who attributed strength loss to thermodynamic instability of the adhesive/substrate interface due to the presence of moisture. In contrast, for electroplated zinc substrates, activation energies for adhesion loss and corrosion product formation were essentially equal, and were both significantly higher than that for moisture diffusion. Consequently, it was concluded that corrosion of the electroplated zinc layer was responsible for bond strength loss. Formation of corrosion product in the bond was not, therefore, a post-failure phenomenon as was the case for cold rolled steel.     

Effects of a sheet metal stamping lubricant on static strength of adhesive-bonded aluminum alloys

Stamping lubricant is often applied to sheet metal surface to improve the formability. In this study, the effect of stamping lubricant on the strength of adhesive-bonded 1.0-mm-thick bare aluminum (Novelis X610-T4PD) and 0.9-mm-thick bare aluminum (Novelis X626-T4P) joints was investigated. It was found that while a proper amount of lubricant (~2.21 g/m², 1.5?μL lubricant on the 25?×?25 mm coupon) applied on the surface of the substrate had little effect on the joint strength, levels more than 2.21 g/m² lubricant significantly decreased the joint strength. When the lubricant amount exceeds the adhesive’s compatibility with the lubricant, the negative effects of pores from lubricant evaporation during curing on the strength overrides the positive effect of increased adhesion energy. Furthermore, the presence of 2.21 g/m² lubricant minimized the reduction of the strength of the joints pre-exposed to neutral salt spray (i.e. a concentration of 50?±?5 g/L sodium chloride solution). Careful analyses of the results indicated that corrosion of aluminum substrate surfaces of the pre-exposed joints led to the degradation in bond adhesion between the adhesive and substrates, and consequently resulted in the decrease of the joint strength. The hydrophobic lubricant protected the aluminum substrate from electrochemical reaction by damage of the bond adhesion between the adhesive and substrates leading to the lubricated joints having better corrosion resistance than the unlubricated joints.     

石油工业含油污水处理工艺技术

阐述了油田含油污水的来源、特征、分类及其危害等相关内容,针对石油石化工业含油污水的处理方法进行简述,指出了含油废水处理的过程中存在的问题。     

Suitability of Printing Materials for Heat-Induced Inkless Eco-Printing

Pyrolysis volatiles and the environmental impact of printing paper, newspaper, and silk were investigated to identify suitable materials for heat-induced eco-printing (HIEP) using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Furthermore, the printing effects of simulated HIEP and the material microstructures were studied using scanning electron microscopy (SEM). The results indicated that the toxicity of pyrolysis volatiles is highest for newspaper, followed by silk and then printing paper, whereas environmental friendliness follows the opposite trend. A high concentration of lignin, the basic structural element of which is phenyl propane, and the presence of halogens in the newspaper led to the generation of more toxic substances during the pyrolysis process. The benzene compounds and heterocyclic compounds in silk also produced high levels of toxic substances. Based on these findings and the higher color permeability of newspaper, printing paper was the most suitable material for HIEP and newspaper was the least suitable. Additionally, silk may still be used in HIEP in small amounts for the production of art, name cards, and clothing tags.     

工科院校环境专业有机化学的教学探讨

有机化学是环境专业重要基础课程之一。掌握扎实的有机化学基础知识和基本技能是环境专业学生今后进行环境保护特别是有机物污染的控制和改善的关键。文章针对工科院校环境专业学生的特点及有机化学学科特点,结合教师自身教学的经验和体会,从教学过程的薰要三环节即备课—授课-实验着手,对如何提高有机化学课堂教学效果进行了探讨。     

环境工程专业物理化学教学改革

文章把物理化学教学与环境工程专业的专业特点结合起来,结合多年的教学实践,从物理化学课程的教学内容、多媒体教学手段、教学考核等方面探讨了物理化学的教学改革,从而显著提高教学质量。     

Removal of copper by modified chitosan adsorptive membrane

In this study, a novel adsorptive membrane was prepared from chitosan as the functional polymer and some additive blend solutions by solution casting method. The modified chitosan membrane was characterized by FTIR and its Water Swelling Ratio (WSR). The adsorption of copper ions on the adsorptive membrane was investigated in batch experiments. The results obtained from the experiments indicated that the membrane had a good adsorption capacity for copper ions, the optimal ionic strength and pH were 0.1 and 5–6, respectively. Compared with the Langmuir isotherm model, the experimental data were found to be following the Freundlich model.