نشریه انسان و محیط زیست
سال دهم شماره 1 (پیاپی 20، بهار 1391)

Leakage of toxic، flammable and dangerous materials in process and chemical industries has always been one of the hazardous for working people and residents around these industries and damaging the environment as well. Propane and combustion gas are important hazardous materials in these kinds of industries. because of its special condition of maintenance, environment`s and storage in big tanks for consumption into production units, have chance bring about tens of people death from leakage and explosion of this gas. Although special precautions are considered to prevent release of material and occurring such incidents but releases, explosion and non stochastic incident `s occur mostly because of human errors during the unit control or during repairing. Therefore, the study of incident consequences using risk assessment procedures and atmospheric diffusion models is one of influential method in doing preventive measures. Today to quantitating of risk (QRA), different software models such as SLAB-DEGADIS-PHAST and ALOHA Have been provided for modeling the release of toxic, flammable and hazardous materials. Each of these software has certain properties appropriate to its own applications. Additionally, By modeling of material release using reliable software, not only the affected area by release of toxic، flammable and hazardous materials could be determined, but emergency response program (proactive, in process and reactive) could also be planned with use conclusion of modeling. This case study is, an industry of Tehran. given input `s element of software according to weather and obtained concentration in 1 Km is17times of TLV and that`s limit of effectiveness explosive ment. because that cause to 916 human personal and 130 passenger are die, also sustain a loss approximate at least 4/010/000/000/000 rial. that explain recommend` s e. g construction and equipped of crisis management station, rescue and resuscitation center, construction of dick, barrier and control of automobile`s, EX proofing of equipment`s near to tank to prevent and control of incident from release.

An overwhelming problem of modern life in large and industrial cities can be considered as air pollution. In order to reduce the air pollution harmful consequences، it necessitates finding out crucial air pollution parameters and their lateral effects. In this study، meteorological and air pollution data in Tehran were investigated; afterwards the changes in annual mean and correlation of these parameters and their linear model environmental pollutants were determined based on the meteorological parameters. Meteorological parameters، the important parameters in specifying the air pollution، have been scrutinized in this study. Tehran Air Quality Index pollutants variables (NO2، SO2، O3، CO، PM-10) and meteorological elements can be named as if temperature، relative humidity and wind speed. Meteorological and pollutant data were obtained from، synoptic and department of environment study stations. There of the average annual change of these parameters، correlation and linear model of environmental pollutants based on meteorological parameters has been acquired via statistical software. The results، estimated from 60 equations، illustrated that only through 40 equations the relations between pollutants and meteorological parameters was observed in which the differences in number of sample، type of relation and degree of correlation existed. The best equation with more than 49% coefficient of determination for ozone versus temperature was recognized in Azadi station. This correlation for SO2 versus wind speed with more than 24. 9% coefficient of determination was calculated in Vila station. Pardisan station for SO2 versus temperature with more than 32. 3% coefficient of determination and Tajrish station for ozone versus temperature coefficient of determination of more than 22. 4% were selected as the most outstanding equations. With regard to the fact of the significance of the relation between pollutants and meteorological parameters، it perceived that weather parameters can be effective on the air pollution levels in Tehran.

Technology seawater reverse osmosis (SWRO) desalination plants water desalination in recent decades due to the use of energy recovery devices (ERDs)، modern technology in manufacturing membrane of growth enjoys. Several systems for energy recovery in SWRO happen that each has its own advantages and disadvantages are. This article reviews and evaluates the use of devices، energy recovery in the basin، an important catchment area in the north (Gulf of Gorgan) and south (Persian Gulf) in order to provide drinking water in urban areas of the law of the subsidies in the energy sector in 90 years is. For this purpose، each of the devices recovered as described، then the software Rosa parameters necessary to produce 20،000 cubic meters per day set، and energy in particular (SEC) in four-wheel Pelton، Turbocharger، pressure exchanger / work to help the software calculated based on energy prices and 90 years of annual energy costs (total power) in both basins has been calculated. With detailed analysis and comparison of energy consumption in both basin and 41% wheel Pelton of pressure / work close to 50% of energy consumption are reduced. Pressure exchanger with high performance and price pressure due to the high price of energy and is recommended for both catchment Pelton turbines.

Global warming occurs due to the increase of greenhouse gases emission including CO2، the consequence of which would be the drastic changes in the Earth''s climate. Due to the consumption of fossil fuels and the chemical processes used to produce cement at the stage of heating the raw material، the net amount of CO2 gas production in the cement industry is about 15 to 25%. The present research discusses the technical feasibility of recycling CO2 in Abyek Cement Complex، which is known as large cement industry in the country with the production capacity of about 12،500 tons per day on two production lines. The main fuel of furnaces in this industry is heavy oil. Due to the combustion، the gases emitted from the five-stage pre heater include 24. 5% CO2، 7. 6% H2O، 48% O2 by volume and 61. 3% N2. With respect to the analysis of gases emitted from the furnace of Abyek Cement Complex and the factory''s available facilities، the absorption was designed using post combustion process through the chemical absorption method using Monoethanolamine (MEA) by HYSYS software. The required equipment of the process was simulated and optimized and dimensions of all the process components were determined. The results show that approximately 117 ton per hour of CO2 with the efficiency of 97% at C with moisture content (1179 kg/h)، Oxygen (2. 5 kg/h)، and nitrogen (16. 5 kg/h) is absorbed which can be transferred to the consuming centers after pressurization and condensation.

Emission of hydrocarbon pollutants requires application of refining methods that is appropriate and compatible with environment to reduce or eliminate pollution. The use of microorganisms، capable of feeding oil hydrocarbons with focus on methods of bioremediation oil decomposition was considered، and optimizing the growth conditions can increase their efficiency in refining. The purpose of this study is to determine the optimal conditions for the stimulation of soil microorganisms and investigation of oil hydrocarbon decomposition potential. Hence، Ray''s refinery contaminated soil was used and treatments including inoculation of bacteria''s such as: Bacillus subtitles، Bacillus megaterium، Pseudomonas putida were applied on this soil during the five time and analysis of total soil hydrocarbons petroleum (38%) were compared with the treatments in different conditions. Results showed that on the first and second period، animal manure treatment، bacteria mixed by animal manure and sawdust had the highest rate of pollution reduction but treatments included N + P + K fertilizers showed higher efficiency in the third period. The establishment of bacterial and application of NPK nutrients caused the stimulation of soil microorganisms and increase in their population. Eventually In the fifth period، the establishment of microbial treatment caused 19% reduction in comparison with intact treatment that is highest reduction in this treatment. It appeared this treatment had maximum efficiency for the establishment and stability of microbial community over required time.

The objective of this study is to investigate the possibility of using a microbial mix to biodegrade the chemical wastewater (mainly phenol compounds) of the Mobarakeh steel factory (Esfahan-Iran) adsorbed on granular activated carbon (GAC) and to determine the adsorption capacity of the bioregenerated GAC. The apparatus consisted of a continuous reactor made of glass with the dimensions of 43 × 29 × 50 cm (L × W × H)، with continuous airing supplied by a compressor and a 24-h feeding system. The microbes were acclimated for 3 months inside the reactor under these conditions: temperature of 30 ± 1 ºC، continuous feeding with a synthetic wastewater (C12H22O11 - CO (NH2) 2 - Na2HPo4 at a daily loading rate of 1000 mg COD/L day) and continuous airing by the compressor. After the acclimation period (3 months)، 300 g of the used GAC is introduced into the reactor، and a 2-month period of bioregeneration is started. At the beginning of this period، the COD of the feed solution was 500 mg L-1 as in the other studies and the amounts of mixed liquor suspended solids (MLSS) was 2420 (mg L-1). The regeneration efficiency (RE) increases from 6% on day 7 of the bioregeneration process to 28% on day 53، with the MLSS increasing from 3520 mg L-1 on day 7 to 13460 mg L-1 on day 53. The results indicate that the increase of MLSS affects the regeneration efficiency of GAC. The phenol adsorption capacities of the new GAC، used GAC (without bioregeneration)، bioregenerated GAC (for 7 days) and the bioregenerated GAC (for 53 days) were 90. 87، 0. 00، 5. 06 and 26. 29 mg L-1، respectively. Therefore، the adsorption capacity of the 53-day bioregenerated GAC was higher than that of the used GAC without regeneration and of the GAC bioregenerated for shorter periods (7، 14، 23، 38، 45 days). This demonstrates that the bioregenerated GAC can be recycled and used for phenol adsorption for longer periods

Due to high demands for wood products as lumbers، panels as well as wood products and also regarding deficit of wood sources in the country، attentions are changing to substitute wood products with wood plastic composites made from wood wastes. Therefore، it provides opportunities to solve environmental aspects of the waste materials as well as use very low cost sources for production. This research work has been concerned to study swelling of wood plastic composites made from different ratios of wood waste manufactured by two techniques of extrusion and hot press modeling. The samples were made based on target density of 1 g/cm3 and dimensions as 35×35×1cm from beech wood flours as wastes and polypropylene with mixing ratios of 40، 50 and 60%. The samples were made with two techniques of extrusion modeling and hot press modeling. Results revealed that any increase of wood particles ratio from 40 to 60% increased the thickness swelling of the wood plastic samples. It was also shown that composites with higher ratios of the wood flours achieved to their maxima of the saturation within a shorter period. Boards molded samples with hot press had lower swelling than that of the extruded molding.

Coastal areas are very vulnerable for pollution. Despite the fact that such areas are benefiting from verity of biological resources of marine and inland systems، they are exposed to destructive threats from both systems. Nowadays، one of the main sources of threat is the large probability of occurrence maritime accidents that caused oil spill. Therefore، identification of sensitive coastal areas and its protection against pollutants such as petroleum products has become a priority for coastal countries. The purpose of this research is to introduce a guideline for mapping of Environmental Sensitivity Index (ESI)، as a tool for identification of coastal areas، sensitive to oil spill، developed by National Oceanic and Atmospheric Administration (NOAA) of United States of America. The goal of such identification is timely response to oil spill and cleanup process for protection of the various coastal ecosystems. In past few decades، Environmental sensitivity analysis and mapping projects have been carried out in many Countries، along thousands of kilometers of shoreline around the world، primarily as a part of national efforts to establish a knowledge-based response system to spilled oil that may affect the coastline

The soil macrofauna are the most important terriocolous (invertebrates) section in small and micro and trummage in the them، on the other hand، the creation of pores and increases soils، porosity are a very important role it، also change method tending of north forests to single selection system، individual trees is done، that result creation canopy gap. Also throught the trees to mark، trees breeding stand and regeneration will be created، so the most important stage، interference human in the forest stand. This study was conducted wether soil macrofaunabiodaiversity under canopy with canopy gap in soil layers. Diversity soil macrofauna including earthworm، diplopoda and chilopoda were extracted 10×10×10 cm soil by hand-sorting procedure. Diversity (shanon H index) and evenes (smith-willson) were analyzed using. Results show that there are significant differences between groups under canopy with groups’ canopy gap hence biodiversity indicators in 99% level

Earthworms are important factors in soil formation and nutrient cycles. These organisms rummage soil and reform its particles and structure that are too important in succession. Earthworm frequency is related to the component of plant residues because they were nourishrd by organic matter، litter and plant residues. So kind، substance and chemical component of plant residues effect on their population and activities. Because organic matter in forests is abundant، earthworms can be introduced as the most important factor that influences on soil fertilities and improvement of it. So we studied reciprocal relationship and correlation of earthworms and forests to show how they enrich and improve soil fertilities.