印刷线路板电镀废水综合治理

简述线路板电镀废水中氰、铜氨、油墨废水治理方法和混合废水综合治理工艺流程及原理。     

高压天然气球罐施工控制要点

详细介绍了2000m^3高压天然气球罐工程的制造、安装过程，并指出每个环节的控制要点。球罐投入运行后，工作状况良好。     

Preparation of zeolitic adsorbents from waste coal fly ash

Power plants burning coal generate a large amount of fly ash as waste matter. The objective of this study is to produce zeolitic adsorbents that possesses high adsorptive capacity for toxic cations. The sample was first pretreated with a High Intensity Magnetic Separator for the removal of iron and magnetic materials (mainly Fe₂O₃ and TiO₂). The zeolitic adsorbents were prepared under the various conditions of NaOH concentration (1–5 N), reaction time from 3 to 96 hours and at the various temperatures of 60, 80 and 100°C. The results of the experiment showed that the coal fly ash should be synthesized with 4 N NaOH for 48 hours at 100°C in order to have good adsorptive capacity. The zeolitic adsorbents showed higher cation exchange capacity values than the natural zeolite in removing NH ₄ ⁺ , Pb²⁺, Ca²⁺and Cd²⁺ions.     

Soil Apparent Electrical Conductivity (EC<Subscript>a</Subscript>) as a Means of Monitoring Changesin Soil Inorganic N on Heterogeneous Morainic Soils in SE Norway During Two Growing Seasons

An efficient method to monitor changes in soil inorganic N content during crop growth would be a useful means to guide N fertilization to ensure high yields and low N losses to the environment. In this study, soil apparent electrical conductivity (EC_a) measured by the widely used conductivity meter EM38 was tested as an indirect measurement of available N in spring barley during two cropping seasons at two sites with morainic loam in SE Norway. The experiment was constructed to maximize soil variation. In spite of the ȁ8noiseȁ9 caused by the soil heterogeneity, concentrations of inorganic N (cN_inorg) or NO₃-N were most strongly correlated with EC_a in both years and at both locations (with one exception). The measurements of EC_a reflected well the temporal variation in inorganic N content (N_inorg), and a ranking of the treatments based on EC_a fitted very well with a ranking based on N_inorg at the first three sampling times after fertilizing. The best subset of sensor variables (i.e. variables which can be measured ȁ8on-the-goȁ9 by sensor techniques in the field) described 27–69% (average 47%) of the variation in topsoil cN_inorg. When expanding the regression models to include pH as well, the degree of explanation increased significantly. In conclusion, the method of using EC_a appears to be quite robust in terms of detecting relative differences in cN_inorg, whereas a determination of absolute levels of cN_inorg with the method is unreliable.     

Exergy Identification Of Energy Utilization Efficiency In an Industrial Process of Ozone Generation

The main objective of the paper is to establish an arrangement of sources of exergy losses (internal and external ones) and to estimate the value of the losses in an industrial ozone production installation. An exergetic model of industrial installation in a system approach corresponding to real conditions has been formulated.     

Ozone Contactor Hydrodynamics

Tracer tests were conducted at the 6,000 pounds of ozone per day Tucson, CAP Water Treatment Plant in Tucson, Arizona. The tests were designed to determine T₁₀ values through the contactors at various operating conditions. The tests were modeled using three techniques. Peclet Number was calculated for each of the runs, which would indicate the hydrodynamic conditions inside the ozone contactor. The results indicated that the increase in water flow rate and the number of cells with gas flow increased Peclet Number. The flow rate of liquid seemed to impact the Peclet Number more than gas flow. The headloss in each cell appeared to be important in controlling the distribution of liquid and gas through the cell. A correlation was developed between the product of gas and liquid phase Reynolds Number and Peclet Number.     

Fluorescent Brightener 28 Removal by Ozonation or Advanced Oxidation Processes (O3/H2O2)

The aim of this work is to study the reaction of ozone and combined ozone/hydrogen peroxide mixtures with the fluorescent brightener 28 in dilute aqueous solution using controlled experimental conditions. The kinetics were also evaluated under various experimental conditions. The main ozonation by-products have been identified by High Pressure Anionic Exchange Chromatography (HPAEC) and Gas Chromatography coupled with Mass Spectrometry (GC-MS) techniques and a reaction pathway is proposed. In order to confirm this mechanism, melamine and s-triazine have been treated under the same reaction conditions and their decomposition pathways were studied.     

Optimal Ozone Production From Air

In this paper, another achieved example of Lunt's theory of chemical reactions in electrical discharges is emphasized. From an economic viewpoint, it is shown for a given mean value of the plasma temperature that the ozone yield of an air-fed cold plasma reactor presents an optimal value depending on the reduced electrical field, as expected from theoretical developments.     

Domestic and Industrial Wastewater Treatment with Ozonated Activated Sludge

Poor sludge settleability is a problem encountered in many activated sludge wastewater treatment plants. This study was aimed at combatting the unwanted biological growths at the root of this phenomenon with ozone. Ozone dosed directly into the aeration basins of small activated sludge pilot plants treating both domestic and synthetic fuel wastewaters led to a substantial reduction of the bulking problem even at dosages as low as 6 to 10 mg/L. Ozone did not interfere in the delicate nutrient removal processes and significantly enhanced effluent quality.