Use of chemical fibre manufacturing wastes for modification of petroleum paving asphalts

The effectiveness of using large-tonnage wastes from chemical fibre manufacturing plants for modifying petroleum paving asphalts is demonstrated. Addition of bottoms and acetate fibre wastes in the amount of 0.3 to 0.4 wt. % to asphalt—rubber composite reduces the ductility of the composite at 0°C by 20–70% and insignificantly affects the ductility of the composite at 25°C. Penatration of the composite is insignificantly altered. The softening point of the composite increases slightly. When the bottoms content in the composite is increased, the effect of increasing the fibre content becomes more even. This indicates the slight damping effect of the bottoms. Addition of acetate fibre to the polymer—asphalt binder in the amount of up to 0.4% increases the R & B softening point by 5–15%. IR spectroscopy showed the formation of hydrogen bonds between the polar groups in the bottoms and the oxygen- and nitrogen-containing groups in the asphalt.Translated from Khimicheskie Volokna, No. 5, pp. 52–55 September–October, 2004.     

Photocatalytic decomposition of nonbiodegradable substances in wastewater from an acrylic fibre manufacturing process

The testing samples in this experiment were obtained from an acrylic fibre manufacturing companys industrial wastewater. The water was the waste of the acrylic polymerization process. The company is located in Ulsan, Korea. The concentration of acrylonitrile (AN) in the wastewater was about 25–35 mg/L. Concentrations of 3–10 mg/ L of methyl acrylate (M-35) were also found. The samples were treated by the TiO₂/UV system and were analyzed to determine the values of COD_cr, ammonia, nitrite nitrogen, and nitrate nitrogen by using an Auto Analyzer (Bran+ Luebbe, Germany) and a TOC (Tekmar Dohrmann, USA). Various reaction parameters, such as TiO₂ content, light intensity and wavelength, and the number of UV lamps were varied and their effects or decomposition efficiency were analyzed. The adsorption onto TiO₂ surfaces by organic materials in the wastewater was negligible. The reaction-rate constant was also calculated. The reaction rate constant for the G36T6L lamp at both 185 nm and 256 nm was 0.0661 hr^-1 which is 1.3 times higher than that of the TUV36T5 lamp at 256 nm. While the reaction rate was increased by increasing the surface area of the photocatalyst, the excess photocatalyst blocked the light sources, causing a photoenclosure effect. The stability of the treated wastewater was greatly increased because the elimination of the concentration of nitrite was followed by an increase in the concentration of nitrate. Generally, the ratio of BOD₅/COD_cr is used as the criterion for determining biodegradability. A ratio of 0.3 is needed for biological degradation. The ratio of the treated wastewater increased to 0.5 after 12 hours of reaction. The ratio increased to 0.8 after 20 hours.     

Cleaning up wastewater from viscose fibre manufacture by isolating local streams

Conclusions In viscose fibre plants, it is recommended to localize the absorber solution from the carbon disulfide regeneration unit and route it to a unit for crystallization of sodium thiosulfate.When there are no units for utilization of sodium thiosulfate in plants, or during the period of construction and start-up, it is recommended from the results of these studies to deliver the absorber solution containing sodium thiosulfate to biochemical clean-up together with farm and household wastewater.Translated from Khimicheskie Volokna, No. 5, pp. 10–11, September–October, 1988.     

化学清洗废液的现场处理方法

论述了化学清洗废液的种类及其特征、废液的危害及清洗现场的处理方法,为从事化学清洗人员提供了一些参考手段.     

Use of a lime-sulfur precipitant for purification of wastewater from viscose manufacturing

Conclusions It has been shown that it is very rational to carry out the process of cleaning up zinc-containing wastewater from the manufacture of viscose fibres by precipitating the zinc at pH 7.3–8.5 using a lime-sulfur precipitant. This will make it possible, in cleaning up 1 m³ of wastewater, to reduce the consumption of lime by 0.23 kg, the consumption of sulfuric acid by 0.25 kg, and to avoid secondary contamination of the wastewater with sulfates.The sulfur obtained as a by-product in the process of freeing exhaust discharges from viscose manufacturing from hydrogen sulfide is used for the preparation of the lime-sulfur precipitant.Translated from Khimicheskie Volokna, No. 6, p. 20, November–December, 1984.     

Use of various types of carbon in purifying wastewater from viscose manufacturing from surface-active substances

Conclusions An evaluation of the efficiency of various types of activated carbon has been made: these were anthracites from the Pervomaiskii and Rubezhanskii chemical works, and carbons AR-3, AG-5, and SKT-3; evaluation was in purification of wastewaster from surface-active agents.Activated carbon AG-5 and activated anthracite from the Pervomaiskii chemical works are recommended for purification of acid wastewater from the manufacture of high-modulus viscose fibres from surface-active agents.Translated from Khimicheskie Volokna, No. 6, pp. 21–22, November–December, 1984.     

简述三合一盐酸合成炉的化学清洗工艺

分析了三合一石墨盐酸合成炉冷却系统垢层的生成及影响,提出采用化学清洗方法,可改善其冷却效果。     

Estimate of the harm prevented when wastewater from acetate fibre manufacture is cleaned up

Conclusions The effect of biochemical clean-up of wastewater from acetate fibre on reducing harm to the environment has been determined.The pure economic advantage from prevented harm in cleaning up 100,000 m³ of wastewater from the Kirovakansk Man-made Fibre Plant was 29,676 rubles/year.Translated from Khimicheskie Volokna, No. 5, p. 21, September–October, 1988.     

污水深度回用装置反渗透膜的污染及化学清洗

结合水处理中常见的污染物种类,介绍了污水深度回用装置的反渗透膜污染情况及合理的化学清洗方案。     

焦化蒸氨废水冷却器堵塞原因分析及化学清洗

蒸氨废水冷却器长时间使用后,水通道和废水通道均会发生堵塞,影响两种传热介质正常运行。对堵塞原因进行分析,采用适当的化学药剂进行清洗,可除去水通道和废水通道的堵塞物质,能够增大水流通量,提高换热效率,确保蒸氨废水冷却器的安全运行。     

Anaerobic digestion of organic wastewater from chemical fiber manufacturing plant: Lab and pilot-scale experiments

Chemical fiber manufacturing wastewater (CFMW) usually contains high levels of organic materials. Anaerobic digestion of CFMW was evaluated by the lab and pilot scale experiments in the study. The CFMW used in the experiment characterized an inappropriate C/N ratio and acid pH for anaerobic digestion. The COD removal efficiency, pH and the methane yield were significantly decreased with 5.00 g COD/L day of OLR in the lab scale experiment. These results were thought to be due to the inappropriate C/N ratio and acid pH of CFMW. Thus, the addition of nutrients and neutralization for CFMW were conducted in the pilot scale experiment. Accordingly, the significant decreases in COD removal efficiency and pH were not observed although the OLR increased to 5.00 g COD/L day. The methane yield also increased above 25% compared to that of the lab scale experiment. In the case of 1,4-dioxane, the removal efficiency was not improved significantly at the higher HRT. It was considered that constant proportion of acetic acid was used in the degradation of 1,4-dioxane as a cosubstrate regardless of HRT.     

化学清洗与物理清洗技术在工业清洗中的联合应用

通过对某换热器及某小区供暖系统管路的清洗实例,介绍了化学清洗与物理清洗应用技术。实践证明,两种技术相结合与使用单一的清洗技术相比,效率更高,效果更好。     

Use of cloth from synthetic fibres to clean up (filter) epoxy resins

Conclusions In the filtration of technological solutions of epoxy resins, one can use cloths based on polyamide, polyester, or polypropylene complex yarn, having 290–420 open (interfilament) pores per cm² and through porosity of 5–22%; these have a low hydraulic resistance and permit one to attain the best filtrate quality. They can successfully replace the types of cloths from natural fibres which are being used at present.It is advisable to carry out laboratory evaluation of the suitability of cloths for filtering epoxy resin solutions from the figures for their shrinkage and loss of strength under the action of the solution being filtered; these should not exceed 5–7 and 15–20%, respectively.Translated from Khimicheskie Volokna, No. 4, pp. 48–49, July–August, 1987.     

化学预处理联合UV-Fenton法处理EDTA清洗废液

采用化学预处理联合UV-Fenton光催化氧化法处理EDTA清洗废液,通过单因素实验和正交实验研究了各主要因素对EDTA回收效果及回收后废液COD去除效果的影响。结果表明,在最佳工艺条件下,EDTA的回收率在85%以上,COD去除率高达97.1%,处理后COD降至101.9 mg/L,达到排放标准。     

Use of chemical fibre processing wastes for fabrication of thermoplastic composites

The behavior of the components of an inseparable mixture of processing wastes containing polyamide, polyacrylonitrile, and cellulose fibres was investigated. The possibility of using them in production of wood—polymer composites if cyclization in the structure of PAN and chemical reaction of basic and acid functional groups play the determining role in intensification of the interfacial interaction in the composite and correspondingly in increasing the strength properties of the final product, was demonstrated. The parameters of the process were optimized, and this allowed for obtaining materials with a static bending strength of up to 80 MPa, water absorption of up to 11%, and a degree of swelling of up to 8.3% according to GOST, which satisfies the requirements for brand ST_s-500 ultrahard board materials.St. Petersburg State University of Technology and Design. Wood Technology Academy, St. Petersburg. Translated from Khimicheskie Volokna, No. 6, pp. 39–44, November–December, 1996.     

Computer control of fibre manufacturing from graft copolymers of polycaproamide

Conclusions Possibilities of computer control over the amount of graft polymer and rate of the graft polymerization reaction have been investigated.A method has been proposed for determining the amount of grafted polymer and the rate of graft polymerization using a microcomputer.Translated from Khimicheskie Volokna, No. 2, pp. 56–57, March–April, 1988.     

Technological modeling of clarification of wastewater from viscose manufacturing

Conclusions The kinetics of precipitation of suspended substances has been determined on real wastewater from viscose manufacturing at definite properties of the suspension.The coefficients obtained make it possible to carry out design of a settler for a specific wastewater composition by the procedure of construction norms and specifications.Translated from Khimicheskie Volokna, No. 6, pp. 20–21, November–December, 1988.     

Detoxification of cyanide in wastewater from the manufacture of nitron fibre

Conclusions The method of detoxifying cyanides with hydrogen peroxide in the presence of copper sulfate has been investigated as applicable to wastewater from the manufacture of Nitron fibre.Optimum proportions of hydrogen peroxide and copper sulfate have been found.Translated from Khimicheskie Volokna, No. 6, pp. 25–26, November–December, 1984.