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Showing 3 results for Saghi
Comparison of Diffrent Coagulants Efficiency for Treatment of Hamedan Landfills Leachate Site
M.t Samadi, M. H Saghi, M. Shirzad, J. Hasanvand, S. Rahimi,
Volume 3, Issue 1 (3 2010)
Abstract

Backgrounds and Objectives:In Iran , indicated that the municipal landfill leachate has been one of the major problem for environment. In the operations, leachate treatment is a very difficult and expensive process. Although, young leachate can be treated easily by biological treatment, COD removal efficiency are usually low due to high ammonium ion content and the presence of toxic compounds such as metal ions. Treatment of leachate is necessary.The aim of this study is reduction of Chemical Oxygen Demond (COD) and Total Suspended Solids (TSS) from hamedan city sanitary landfill leachate by three coagulants: alum, PAC and ferrous sulfate.
Materials and Methods: This experimental study was conducted to investigate the effect of treatment of landfill leachate by a coagulation-flocculation process. The effects of different amounts of coagulant and different pH values on the coagulation processes were compared.
Results:Result shown the high efficiency for reduction of CODby PAC in pH=12 and concentration of 2500(mg/l (62.66%), and by alum in pH=12 and concentration of 1000 (mg/l) (60%) , by ferrous sulfate in pH=2 and concentration of 1000 (mg/l) (70.62%). Also result shown the high efficiency for TSS removal by PAC in pH=12 and 2500(mg/l) concentration of PAC was 58.37%, with alum in pH=2 and 1500 (mg/l) concentration of alum was39.14% , by ferrous sulfate in pH=7 and 2500(mg/l) concentration of ferrous sulfate was 35.58%.
Conclusion:The best coagulant for COD removal is ferrous sulfate.The physico-chemical process may be used as a useful pretreatment step, especially for fresh leachates, prior to post-treatment (polishing) step for partially stabilized leachates.


Performance of Simple Nano Zeolite Y and Modified Nano Zeolite Y  in Phosphor Removal fromAqueous Solutions
M.t Samadi, M.h Saghi, K. Ghadiri, M. Hadi, M. Beikmohammadi,
Volume 3, Issue 1 (3 2010)
Abstract

Backgrounds and Objectives:Phosphate discharges from domestic and industrial waste water to water bodies. High concentrations of phosphate in water stimulate the eutrophication phenomenon that causes taste and odor in water, losing dissolved oxygen and aquatic life in rivers or surface waters. Aim of this study is survey of phosphate adsorption on simple nano zeolite Y and nano zeolite Y that was modified with a cationic surfactant (HDTMA-Br).
Materials and Methods:In This study we used simple nano zeolite Y and nano zeolite Y in form of Surfactant Modified Zeolites (SMZs) using batch tests to adsorption of Phosphate fromAqueous Solutions. The adsorbants were contacted with different initial phosphor concentrations (5, 10 and 15 mg/l), pH (4, 7, 12), contact time (30, 60, 90, 120, 150 and 180 minutes) and weight of adsorbant (0.2, 0.4, 0.6, 0.8 and 1g). the extracted solution was determined for Phosphate concentration by the ammonium molybdate and tin chloride method with spectrophotometric detection at 680 nm. Results:Results of this study show that, with increase in contact time, decrease in pH, increase in zeolites concentration and decrease in initial phosphate concentration, the removal efficiency increased. And the Both isotherm of Langmuir and Freundlich models (r2 > 0.997 and r2 > 0.996 respectively) were agreement with adsorption equilibrium of phosphate. Reduced Chi-Sqr For Langmuir and Freundlich models were (0.00079) and (0.0011) respectively. Pseudo first-order kinetic models fits well with experimental data (r2>0.963).
Conclusion: From this survey, it is concluded that performance of modified nano zeolite Y for adsorption of phosphate in same conditions is better than non-modified zeolite Y. In general the modified nano zeolite Y presented a good profile for removal of phosphate. Therefore SMZs is a suitable candidate for removal of Phosphate molecules from contaminated solutions in contaminated waters.


Study of effect of oregano essential oil and ethanolic extract of propolis on antibacterial properties and some physical characteristics of biodegradable poly-lactic acid films
A Misaghi, M Saeedi, N Noori, Mr Rezaeigolestani,
Volume 11, Issue 1 (6-2018)
Abstract
Background and Objective: Natural antimicrobial compounds have a valuable capacity to be used in a variety of foods to inhibit growth of foodborne pathogens and spoilage bacteria. The aims of this study were to produce active biodegradable films by incorporation of different percentage of oregano essential oil (OEO) and ethanolic extract of propolis (EEP) into poly-lactic acid (PLA) films, and to evaluate physical and antimicrobial properties of the resulting films. 
Materials and Methods: The active films were produced by solvent casting method, and their thickness and major color parameters were measured using a digital micrometer and a colorimeter instrument, respectively. Afterwards, antibacterial effects of the films were assessed against four common foodborne pathogens, including Staphylococcus aureus, Escherichia coli, Vibrio parahaemolyticus and Listeria monocytogenes, by means of disk diffusion test.
Results: Physical examinations showed that thickness of resultant films significantly was increased (p<0.05) by addition of different concentrations of active agents. Additionally, the presence of them in the structure of films decreased the lightness and increased the redness and yellowness, simultaneously.  While none of the neat PLA film or films with just EEP had no antibacterial effect, all films containing higher percentages of OEO (5 and 10%) were effective against all four tested bacterial strains, and these effects were more significant in case of the gram-positive bacteria. The maximum inhibition zone was recorded for the film containing 10% of OEO and 2% of EEP, which the relevant values were 56.66, 45.46, 17.91 and 17.65 mm for Staphylococcus aureus, Listeria monocytogenes, Vibrio parahaemolyticus and Escherichia coli, respectively.
Conclusion: Based on the findings of this study, the presence of just EEP in the initial formulation of poly-lactic acid films was not effective against the four tested foodborne pathogens, while the addition of this compound to the films containing OEO increased the effective antibacterial properties of the resulting films. As a result, the simultaneous use of these two compounds in the structure of hydrophobic films, such as poly-lactic acid film, can be used to produce active food packaging films.
 

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