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1.
城市生活污水化学除磷试剂的应用比较   总被引:4,自引:0,他引:4  
对化学法除磷的常用试剂铝盐、铁盐和石灰在除磷原理、效果和工艺条件方面进行了比较,并就其在处理后对受纳水体的影响进行了分析评价。  相似文献   

2.
A process for dephosphorization of manganese-containing oxide melts with carbon monoxide was developed and studied for the first time. Thermodynamic analysis showed that, under equilibrium conditions, the reaction of carbon monoxide CO with phosphorus oxide P2O5 contained in a manganese-containing oxide melt does not occur. However, since both of the products of this reaction are gaseous, the reaction may occur if the reaction products are removed from the reaction zone. The dephosphorization of manganese concentrate while blowing carbon monoxide through the molten concentrate was experimentally investigated. The blowing significantly reduced the phosphorus content of the melt: the P: Mn ratio decreased by a factor of 5–10, and the degree of dephosphorization was 70–90%.  相似文献   

3.
A novel carbonized clinoptilolite-rich tuff was studied for phenol removal from water. Zeolite sample carbonization was accomplished in a plasmachemical reactor (pyrolytic chamber) using several types of waste, here specifically waste vegetable residues and starch. Phenol adsorption experiments were performed in the batch system. An industrial activated charcoal and a clinoptilolite-rich tuff hydrofobized with an organic ammonium base were used as the related materials to compare phenol removal efficiency.  相似文献   

4.
Controlled tailoring of mechanical property and wettability is important for designing various functional materials. The integration of these characteristics with waste materials is immensely challenging to achieve, however, it can provide sustainable solutions to combat relevant environmental pollutions and other relevant challenges. Here, the strategic conversion of discarded and valueless waste paper into functional products has been introduced following a catalyst-free chemical approach to tailor both the mechanical property and water wettability at ambient conditions for sustainable waste management and controlling the relevant environmental pollution. In the current design, the controlled and appropriate silanization of waste paper allowed to modulate both the a) porosity and b) compressive modulus of the paper-derived sponges. Further, the association of 1,4-conjugate addition reaction between amine and acrylate groups allowed to obtain an unconventional waste paper-derived chemically ‘reactive’ sponge. The appropriate covalent modification of the residual reactive acrylate groups with selected alkylamines at ambient conditions provided a facile basis to tailor the water wettability from moderate hydrophobicity, adhesive superhydrophobicity to non-adhesive superhydrophobicity. The embedded superhydrophobicity in the waste paper-derived sponge was capable of sustaining large physical deformations, severe physical abrasions, prolonged exposure to harsh aqueous conditions, etc. Further, the waste paper-derived, extremely water-repellent sponges and membranes were successfully extended for proof-of-concept demonstration of a practically relevant outdoor application, where the repetitive remediation of oil spillages has been demonstrated following both selective absorption (25 times) of oils and gravity-driven filtration-based (50 times) separation of oils from oil/water mixtures at different harsh aqueous scenarios.  相似文献   

5.
A suitable analytical method making possible the determination of Gd and other rare-earth elements in samples related to hospital waste water treatment was sought with regard to various aspects of the experiment aimed at monitoring the fate of Gd-based contrast agents in the aquatic environment. The discrepancies and pitfalls of the proposed methodology were considered, resulting in a functional experimental plan. The inductively coupled plasma mass spectrometry (ICP-MS) method was used for the determination of Gd and other rare earth elements in river and hospital waste water and algae Parachlorella kessleri cultured in laboratory experiments. The sample preparation of algae prior to analysis was optimised. The ICP-MS method was validated using a recovery study, sample blanks, reference materials, and comparison with the inductively coupled plasma optical emission spectrometry (ICP-OES) method. The ICP-MS method was confirmed as suitable for monitoring the biosorption/bioaccumulation of Gd in algae and for evaluating the Gd anomaly in hospital waste water and rivers of Eastern Bohemia. In the laboratory experiments, the bioconcentration factors were calculated (all in L kg?1) for algae cultured in inorganic Gd salt (about 1100), in waste water from a magnetic resonance workplace (2300) and in waste water from a hospital waste water treatment plant (4400). A positive Gd anomaly in waters from the river Elbe in the Eastern Bohemia region was found less pronounced in the areas unaffected than in the areas affected by waste waters from hospital.  相似文献   

6.
金属-有机骨架材料用于废水处理   总被引:1,自引:0,他引:1  
废水中的各种有害物质常常具有生物毒性或致癌性,因此如何高效、节能地处理水体污染是一个亟待解决的重要问题。金属-有机骨架材料(metal-organic frameworks, MOFs)是一种新型纳米多孔材料,具有种类多样性、结构可设计性与可调控性、高比表面积及良好的热稳定性等优点,已成为当前化学、材料学科的一个研究热点, 在多个领域显示出潜在的应用前景,尤其是在分离方面。与气相分离相比,MOFs用于液相分离的研究较少。本文综述了近年来MOFs用于含有染料、药物、醇、芳香族化合物、重金属离子及其他离子的废水处理的研究进展,重点剖析了MOFs的孔结构、骨架电荷及功能性对分离效果的影响,并结合本课题组的研究工作,对这种新型多功能材料在水处理方面的前景和今后的研究重点作了展望。  相似文献   

7.
Summary An attempt was made to obtain mineral-carbon sorbents from waste products of petrochemical industry: lime from the decarbonization of river water to be used in technology and hydrocarbon wastes obtained in the treatment of industrial waste waters. The sorbents were prepared by thermal decomposition of mixtures of the mineral and carbon components. In order to optimize the preparation conditions, physicochemical studies were performed of both the mineral matrix and the mineral-carbon sorbents. Adsorption measurements involving nitrogen, water, and benzene as adsorbates were used for determining the parameters of porous structure of the obtained materials and their hydrophilic-hydrophobic properties. The properties influencing the sorptive properties of the organic compounds present in the petrochemical wastes were pointed out.  相似文献   

8.
Gasification of several organic materials in steam plasma generated in a special plasma torch with a water-stabilized arc was investigated. Thermal plasma with very high enthalpy and low mass flow rate is produced in an arc discharge which is in direct contact with water. Biomass and several types of solid and liquid organic waste were gasified by plasma aided reactions of materials with water, carbon dioxide and oxygen. Composition of produced gas, energy balance of gasification process and gasification efficiency were determined from measured data. Synthesis gas with high content of hydrogen and carbon monoxide and very low content of carbon dioxide, light hydrocarbons and tar was obtained for all tested materials. Comparison of measured data with results of theoretical computations confirmed that steam plasma gasification produces syngas with composition which is close to the one obtained from thermodynamic equilibrium calculations.  相似文献   

9.
The artificial water cycle can be divided into the phases of water capture from the environment, potabilisation, distribution, waste water collection, waste water treatment and discharge back into the environment. The terminal phase of this cycle, from waste water collection to discharge into the environment, was assessed by emergy analysis. Emergy is the quantity of solar energy needed directly or indirectly to provide a product or energy flow in a given process. The emergy flow attributed to a process is therefore an index of the past and present environmental cost to support it. Six municipalities on the western side of the province of Bologna were analysed. Waste water collection is managed by the municipal councils and treatment is carried out in plants managed by a service company. Waste water collection was analysed by compiling a mass balance of the sewer system serving the six municipalities, including construction materials and sand for laying the pipelines. Emergy analysis of the water treatment plants was also carried out. The results show that the great quantity of emergy required to treat a gram of water is largely due to input of non renewable fossil fuels. As found in our previous analysis of the first part of the cycle, treatment is likewise characterised by high expenditure of non renewable resources, indicating a correlation with energy flows.  相似文献   

10.
Mathematical models of the of industrial waste water post-treatment with higher aquatic vegetation in the course of mineral raw materials processing are presented; the method allows the extraction of pollutants to meet the level required by the standard indicators.  相似文献   

11.

The removal of dyes from waste water before their discharge into aquatic ecosystems is of substantial concern. Amongst functional macromolecules, the combination of polymers with dyes is a research field of enormous potential with regard to high-performance materials. The present study investigates interactions strategies between P(AM-co-AA) polymer with pyrazolone azo dyes in water as green solvent. These interactions were confirmed by FTIR spectroscopy, Ultra-visible spectroscopy, EDAX analysis, and FE-SEM analysis. Polymer P(AM-co-AA) has porous structure in which dyes present in the water get absorb hence it is use to remove pyrazolone dyes from water.

  相似文献   

12.
Attempt was made to evaluate the usefulness of thermoanalytical methods, combined with X-ray phase analysis and chemical analyses, for the study of thermal decomposition of waste materials to be subjected to thermal treatment. The object of the studies were petrochemical waste materials intended to be decomposed in a rotary furnace. Results are given of the studies of five selected waste materials. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

13.
The problem of fixation of water pollutants, e. g., nuclear fission and corrosion products is concerned not only with the chemical and physical properties of these materials but also with the type of their dispersal in open waters under natural turbulent conditions. The delivery of a scavenging system into a required depth was the objective of this study. Pellets disintegrating at such a rate as to deliver the required uniform concentration of reacting chemicals into the contaminated body of water were developed. Attempts were made to depart from an empirical approach and to investigate formation and properties of pellets through systematic studies. Parameters investigated were particle size of pelleted chemicals, pelleting pressure and temperature, and age of pellets. Chemicals used were potassium permanganate; ferrous sulfate, anhydrous and heptahydrate; and ferrous chloride, dihydrate and tetrahydrate. The use of pelleted materials for removal of industrial nuclear waste products from water is feasible under emergency and under normal conditions using pellets designed for the specific conditions.  相似文献   

14.
The possibility of using pyrolyzed wastes produced in already working incineration plants, as adsorbents for waste water treatment, was studied. Showing very poor adsorption properties, they were improved by steam activation technique used in the conventional activated carbon manufacturing. It is concluded that various organic waste materials can be converted to carbonaceous final products with a character similar to activated carbon. Their adsorption properties and pore size distribution are determined by the structure of the starting material. Although most of these samples have a low specific surface area, their pore volume is not negligible in the meso-and micropore range. Adsorption tests with model waste waters confirmed that adsorption properties are strongly influenced by the character of the suface. The adsorption capacity of these samples can be utilized for the treatment of strongly polluted industrial waste waters. Considering that the raw material ‘needed’ to manufacture these adsorbent is produced permanently and the adsorbents do not have to be regenerated, it might be worthwhile using these kinds of adsorbents in the primary treatment of industrial waste waters.  相似文献   

15.
A practical, clean, single step oxidative modification of polysaccharides by H(2)O(2) catalysed by water soluble iron phthalocyanine, exemplified with starch, allows quantitative preparation of a range of tailor made materials without producing any waste.  相似文献   

16.
The 2-year international joint project HYCREF (Contract-No. G6RD-CT-2002-00854), funded by the European Commission in the 5th Framework programme, aimed to develop methods to prepare homogenous and stable water-, soil- and waste reference materials contaminated with mineral oil hydrocarbons and to test certify the mineral oil content by gas chromatographic methods. As mineral oil products are important sources for environmental contaminations, appropriate reference materials certified by using the new gas chromatographic methods (soil: ISO/FDIS 16703, waste: prEN 14039 and KW/04, water: ISO 9377-2) are highly needed. Additional to the HYCREF-results presented in part I–mineral contaminated soils–this second paper gives an overview of the feasibility study for the preparation and test certification of three waste reference materials (offshore marine sediment, building material and industrial waste). The following specifications, which had been defined in the project work plan, were reached successfully: uncertainty of the mineral oil content resulting from the certification exercise ≤5% and a between-bottle inhomogeneity of ≤3%. All three materials have been evaluated for long- and short term stability. They contain different levels and types of mineral oil and cover the full application range of ISO/FDIS 16703 and prEN 14039 (100–10,000 mg/kg). The expanded uncertainties U cert of the three materials are about 6%. In this way, they are comparable to ERM®-CC015a (U cert=7.1%, mineral oil in a river sediment) and are suited to close the present gap of commercially available CRM for mineral oil determination in waste.  相似文献   

17.
Phosphate rock (Pho-ore) is the starting raw material used in manufacturing of most phosphate products. This material contains phosphorous, natural uranium, thorium potassium radionuclide and other trace elements. Single super phosphate powder (SSPho-P), single super phosphate granules (SSPho-G), and triple super phosphate (TSPho) are the common phosphate products produced along with phosphogypsym (CaSO4) as a waste product. Since these materials are industrially manufactured by the reaction of the phosphate ore with phosphoric and sulphuric acids, these products and the waste product are extremely acidic. Pho-ore, SSPho-P, SSPho-G, TSPho and CaSO4 samples were used in our study. Chemical analyses showed that these phosphate samples contain phosphorous, iron, aluminum ions and traces of uranium ions. Accumulation of the fertilizers on soils usually transfers some of these ions from the fertilizer materials to the soil/water interfaces. The migration of uranium U(VI), P, Al and Fe in subsurface soils was found to be strongly influenced by the sorption/desorption reaction at the solid/water interfaces. Thus, dissolution of these ions in soil/water phases is very important. Speciation of U(VI), P, Al and Fe in soil/water phases were calculated using a geochemical code (MINTEQA2). This study was conducted to determine sorption properties and the surface electrical properties of these ions at the soil samples.  相似文献   

18.
Polystyrene waste are non-biodegradable materials that causes harm to the environment. Red brick waste resulting from demolition and reconstruction are an obstacle to its disposal. To solve this problem and meet modern sustainability standards, this study utilized polystyrene (PS) foam and red brick construction waste to prepare composite materials (PS/RB-Cs) as a new efficient adsorbent. The PS/RB-Cs composite as an adsorbent was characterized using a UV–Vis Spectrophotometer, Energy Dispersive X-ray Spectroscopy (EDX), Scanning Electron Microscope (SEM), and transmission electron microscopy (TEM), which showed a clear spectrum shift after using PS/RB-Cs as an adsorbent. The PS/RB-Cs was characterized by a porous structure with higher surface area and high stability. The efficiency of the PS/RB-Cs in treating water contaminated with heavy metals such as cobalt and nickel was verified under different initial concentrations, temperatures, doses, pH, and contact times. The experimental qe values were consistent with the qe calculated values and were approximately 8 mg/g. The adsorption isotherm models showed that the adsorption results fit the Langmuir, Freundlich and Flory-Huggins isotherm models and that the process was favorable. By applying pseudo-first-order (PFO) and pseudo-second-order (PSO) kinetic models, the adsorption process was found to follow PSO. The findings of this research validated that the composite material that was prepared serves as a potent adsorbent for the treatment of water that has been polluted by heavy metals.  相似文献   

19.
Pyrolysis of waste materials, biomass wood waste, waste tyre, refuse derived fuel (RDF) and waste plastic was performed using two thermogravimetric analysers (TGA). One TGA was coupled to a mass spectrometer (MS) and the other to an infrared spectrometer (FTIR). The kinetic parameters of the pyrolysed waste materials obtained for TGA-MS and TGA-FTIR were compared using a model based on first-order reactions with a distribution of the activation energies. A further comparison of the volatile species evolved by thermal degradation (TGA) and the subsequent characterisation by the MS and FTIR spectra was performed. The first-order reaction pathways and subsequent activation energies calculated from the differential TGA data presented good repeatability between the TGA-MS and TGA-FTIR. The TGA-MS and TGA-FTIR produced a broad spectrum of qualitative data characterising the volatile gaseous fraction of the waste materials pyrolysed. TGA-MS and TGA-FTIR are shown to be valuable techniques in corroborating the respective thermograms and spectrograms of the volatile species evolved during the pyrolysis of waste materials. However both techniques are prone to interference and careful interpretation of the spectra produced is required.  相似文献   

20.
本文探索了水相中烯烃与溴的加成反应,以四溴双酚A双烯丙基醚为原料,在水相中合成四溴双酚A-双(2,3-二溴丙基)醚,通过考察助剂类型及用量、溴的用量、反应时间、反应温度等因素,优化反应条件,产品收率可达到93.6%,通过HPLC检测纯度达到91.7%。本文借助十二烷基硫酸钠不仅解决了原料不溶于水导致产品团聚的问题,而且此方法后处理简单,无废液产生,简化了工艺路线,可有效降低成本。  相似文献   

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