List of Articles Industrial Wastes

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  1 - Determination of optimal percent mixing of cardboard waste in production of non-load bearing concrete
  Daryoush Yousefi Kebria Seyyedeh Fatemeh Seyyedalipour Mehdi Dehestani
  incineration and disposal methods for their waste production. Hazardous substances contained in thesewastes can contaminate the environment and cause a risk for the human health. Many recent studiesshow that some of the paper and cardboard industry wastes can be used as More

  incineration and disposal methods for their waste production. Hazardous substances contained in thesewastes can contaminate the environment and cause a risk for the human health. Many recent studiesshow that some of the paper and cardboard industry wastes can be used as raw material in theconstruction industry. The aim of this study was to determine the optimal percent mixing of cardboardwaste in production of non-load bearing concrete.Materials and method: In this study, two kinds of recycled paperboard mill wastes (type 1: wastecontains cardboard and sand and type 2: waste containing nylon, cardboard and Yonolit) that have themost volume of the wastes were used. Physical and microbial characteristic of wastes were measuredaccording to ASTM. As well as the chemical composition of the waste consists of various elementswere measured by using an electron microscope. After preparation of the samples, the required testswere carried out to determine the optimal mixture of waste in concrete at the ages of 7, 14 and 28 daysrespectively.Results: Since the pH of fresh concrete containing waste is greater than 12, can be sure that therewill not be any microbiological problem. In general, the use of waste in concrete production reducesthe compressive strength of the samples. Comparing the compressive strength of concrete containingwaste type 1 and concrete samples containing both waste types shows that reducing the amount ofwaste type 2 in compare with waste type 1 improves concrete strength. The results of dry density testshow the density decrease of concrete samples containing waste by increasing the percentage of wastereplacing in the sand. Also using of waste type 2 causes lighter concrete samples in compare withusing waste type 1. Optimal amounts of waste replacement instead of sand for samples containingwaste type 1 and type 2, 70% and 75% ,respectively, as well as for samples containing both wastetypes, 49% of waste type 1 and 21% waste type 2.1- Assistant professor, Department of Civil & Environmental engineering, Babol Noshirvani University ofTechnology, Babol, Iran.2- MSc in Environmental engineering Department of Civil & Environmental engineering, Babol NoshirvaniUniversity of Technology, Babol, Iran.3- 1-Assistant professor, Department of Civil & Eenvironmental engineering, Babol Noshirvani University ofTechnology, Babol, Iran.J.Env.Sci,TechJ.Env. Sci. Tech., Vol 17, No.3, Autumn 2015203Conclusion: According to the results, in terms of economic and environmental benefits, the use ofwaste type 1 in the production of concrete for the lower use of cement is more satisfactory. The use ofpaperboard mill wastes in the production of concrete due to environmental and economical efficiency(profitability and employment, reducing the cost of transferring waste to landfills, reducing structuralweight, using waste instead of buying sand and reduce the environmental pollution caused byincineration and landfilling) is noticeable. Manuscript profile
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  2 - Investigating the reduction of toxicity of the tailings obtained from the processing unit of zinc extraction by solvent extraction method
  Hamid Rahati Asiabar Seyed Mehdi Barqai Roya MafigholamI
  In this research, the ability of solvent extraction to recover zinc from Zanjan Zn extraction unit waste samples has been investigated. This cake contained 180080, 26840, 141040 and 254090 ppm of sulfur, nickel, cadmium and zinc, respectively. Zinc extraction was perfor More

  In this research, the ability of solvent extraction to recover zinc from Zanjan Zn extraction unit waste samples has been investigated. This cake contained 180080, 26840, 141040 and 254090 ppm of sulfur, nickel, cadmium and zinc, respectively. Zinc extraction was performed using Cyanex 272 organic solvent. The investigated variables included pH (in the range of 0 to 1.5), time (in the range of 1 to 6 hours), temperature (60 to 80 °C) and the ratio of solids to solution (10 to 30%). Experiments were designed in Design-Expert software version 7 and using central composite design (CCD). pH was the most influential parameter and temperature was the least important parameter. The highest efficiency was measured with 100% at pH 0, temperature 80°C, ratio of solids to solution 30% and time 6 hours. The lowest zinc removal efficiency with 76.6% occurred at pH 1.5, temperature 60 and ratio of solids to solution 10% and time 3.5 hours. Considering the average zinc removal efficiency of 89.10%, the combination of using Cyanex 272 solvent and pH is a suitable method for extracting zinc from cold cake waste and this method has a high performance. Manuscript profile