Iranian Journal of health, Safety and environment
Volume:1 Issue: 2, Spring 2014

In this study, viability of the autotrophic bacteria was investigated in a denitrification process. Bench-scale bioelectrochemical denitrification with separated chambers reactor were applied for nitrate reduction from synthetic wastewater. The influences of current density, retention time, mixing on viability of autotrophic denitrifying bacteria were investigated in the bioelectrochemical reactor (BER). It was found that by increasing the current density up to 8 mA/cm2, nitrate reduction rate was increased. At higher current density (24 - 32 mA/cm2), denitrification rate due to excess of hydrogen gas on cathode surface and accumulation of nitrite, was decreased. Low current density (<16 mA/cm2) has not had a significant effect on viability of denitrifying bacteria. Mixing of the solution reduced the adverse effects of electric current on bacteria and enhanced the denitrification rate which was mainly due to prevention of bacteria localization, increasing the contact of hydrogen and bacteria, and delay in membrane fouling. The viability of cultivable bacteria has not been significantly influenced by running time.

Acidic sludge is a by-product from used motor oil reprocessing industries, which thousand tons of this sludge are disposed into the environment as a hazardous waste material daily. The acidic sludge contains unsaturated compounds that are polar and asphaltene. The bitumen under certain conditions is produced from mixing of bentonite, polymer styrene – butadiene – styrene (SBS), and acidic sludge.Context and The objective of this study was the recovery of acidic sludge to bitumen using additives such as bentonite and SBS. Also, the effect of additives with different weight percentages (wt%(on the performance parameters of bitumen was evaluated. At first, spilled oil was separated from the acidic sludge by a centrifugal concentrator. Then, concentrated acidic sludge and additives were mixed in together. Finally, the performance tests were carried out to compare the quality of acidic sludge with the obtained products.The results indicated that performance parameters such as softening point (SP), weight loss, penetration degree, PI, Frass breaking point, and temperature susceptibility (TS) were promoted from 37°C, 1.3%, 230 dmm, -0.07854, -5°C and 0.0451 to 54°C, 1%, 130 dmm, 2.7094, -11°C, 0.02721, respectively. According to the paired sample t-test analysis, a significant difference was found between the bentonite dosage and the improved performance parameters from concentrated acidic sludge and obtained products (pvalue ≤.001). The bentonite and SBS with 2 and 4 wt%, respectively were determined as the suitable additives in the recovery of acidic sludge to bitumen.

Wetlands now days apply as a polishing system for the classical wastewater treatment, in addition of different usages. Usually wetland systems are inexpensive methods vs. expensive high technology treatment systems. Objective of this study is an evaluation of natural wetland treatment in polishing of a septic effluent. Research duration works extended for 10 months on a natural wetland system in Pardis of Mazandaran University of medical sciences and eastern north of health faculty. Wastewater quality index such as pH, EC, BOD, COD, TSS, Nitrate, Phosphorus, Ammonia and Temperature performed on the samples of influent and effluent of the system. The study showed the system works as a buffering system for flow and pH. Results indicated that average of BOD5 and TSS efficiency were 67.70and 83%, respectively. Efficiency of COD was 65.26 and 80 % for a Low and moderate strength influent respectively. Average of phosphorus, NH3 and Nitrate in effluent were 0.032 mg/L, 7.18 and 0.036 mg/L, respectively. Efficiency of ammonia and Phosphorus were slightly increased in best condition. Based on this study result, natural wetland can be success in BOD, COD, and TSS removal of the classical septic tank, but for nitrogen and Phosphorus removal do not have considerable effects.

Accident analysis shows that one of the main reasons for accidents is non-integration of maintenance units with safety. Merging these two processes through an integrated system can reduce and or eliminate accidents, diseases, and environmental pollution. These issues lead to improvement in organizational performance, as well. The aim of this study is to design and establish an integrated system for obtaining the aforementioned goal. Integration was carried out at Nirou Moharreke Machine Tools Company via Structured System Analysis & Design Method (SSADM). In order to measure the effectiveness of the system, selected indexes were compared using statistical methods prior and after system establishment. Results show that the accident severity index reduced from 135.46 in 2010, to 43.85 in 2012. Moreover, system effectiveness improved equipment reliability and availability (e.g. reliability of the Pfeiffer Milling machine (P (t>50)) increased from 0.89 in 2010, to 0.9 in 2012. This system by forecasting various failures, and planning and designing the required operations for preventing occurrence of these failures, plays an important role in improving safety conditions of equipment, and increasing organizational performance, and is capable of presenting an excellent accident prevention program.

The Authenticity of meat products is very important for religious and health reasons in Iran. According to legislation in Iran, the consumption and importation of pork, horse, donkey and cat products should be banned. Therefore, the identification of meat products cannot be judged solely by its appearance. This issue led to the authenticity of bovine, sheep, pig, horse, donkey, chicken and soya (Glycine max) in raw and processed meat products.In this study, specific primers were designed for the identification of pig (194 base pair), donkey (325 base pair), chicken (391 base pair), sheep (499 base pair), horse (607 base pair), soya (707 base pair) and bovine (853 base pair) by Polymerase chain reaction. Following PCR, expected494, 325,391, 499,607, 707 and 853 base pair fragments were detectable in pig, donkey, chicken, sheep, horse, soya and bovine, respectively. This protocol can be used for identification of raw and processed meat products in various animal species for replication to regulatory obligations for meat species safety in Iran.

Developing technology and using equipment in Iranian industries caused that maintenance system would be more important to use. Using proper management techniques not only increase the performance of production system but also reduce the failures and costs. The aim of this study was to determine the quality of maintenance system and the effects of its components on failures of kilns in two gypsum production companies using Failure Modes and Effects Analysis (FMEA). Furthermore the costs of failures were studied.After the study of gypsum production steps in the factories, FMEA was conducted by the determination of analysis insight, information gathering, making list of kilns’ component and filling up the FMEA’s tables. The effects of failures on production, how to fail, failure rate, failure severity, and control measures were studied. The evaluation of maintenance system was studied by a check list including questions related to system components. The costs of failures were determined by refer in accounting notebooks and interview with the head of accounting department. It was found the total qualities of maintenance system in NO.1 was more than NO.2 but because of lower quality of NO.1’s kiln design, number of failures and their costs were more. In addition it was determined that repair costs in NO.2’s kiln were about one third of NO.1’s. The low severity failures caused the most costs in comparison to the moderate and low ones.The technical characteristics of kilns were appeared to be the most important factors in reducing of failures and costs.

Karoon River is the main source of drinking, industrial and agricultural utility in Ahwaz city. Protozoans are useful indicators for river water pollution. The aim of this study was to identify and enumerate Dominant protozoans in Karoon Water River, Ahwaz city. In this descriptive study, we took samples from 3 points of karoon river in Ahwaz city boundaries (upstream- uptake point for water treatment plant, middle and downstream) in two seasons (dry and wet). Samples prepared and examined by optic microscope. The results showed 6 species of mastigophora and ciliophora. Most prevalent species were Monosiga fusiformis, Bodocaudatus، Cercomonas Longicauda، Cercomonas Crassicauda، Tetramitus descissus And Stalked Ciliate. The seasonal variation difference was statistically significant. Minimum concentration was in January (less than 1 cell /lit) and maximum was in October (1600 cell/ lit). The average concentration of protozoans was 129. 68 cells/ lit. Protozoans in 3 sampling stations were statistically different, where in 2 and 3 stations Bodocaudatus, Cercomonas Longicauda, Cercomonas Crassicauda, and Tetramitusdescissus were dominant. Identified protozoan species indicate pollution of Karoon River by sewage discharge.