JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY
Year:2001 | Volume:- | Issue:10|Papers Count:7

Doroodzan Dam is located in Fars Province (near Shiraz- 90 km) and Doroodzan watershed (425.400 ha area) was studied for defining of evaluation of environmental capabilities and 'Site selection for recreational use.The objective of this study was.Description of Doroodzan dam and recreational specifications of the region.Description of Environment in these fields:Physical Environment (topography, physiography, climate and meteorology, geology & soil specifications, water resources, erosion)Biological Environment (vegetation, wild life, habitats)Preparation of basic maps such as topography, slope elevation classes, direction of slope, land form unit, soil, vegetationThese maps overlaid by Mc. Harg method and environmental units map prepared.Based on ecological model, the suitable polygons for recreational land use has identified and recreational land use map has prepared.The best recreational site was selected as a result of this map, specifications of ecological model and socio-economical specifications.After site selection, A management plan for recreational center was prepared main tasks of this plan are including:Prediction of carrying capacity of the site.Defining of Camping and Picnic locations.Identification of main environmental impacts and regarding mitigation plan such as waste management and conservation aspects for treatened animal and plant species.

The sediment cores have high Al and organic meter contents due to the high sedimentation rate and their proximity to river mouths. Down-core variations of elements indicate a decrease/decreasing importance of the detrital component during probably the past few centuries. While abundance of Calcareous shells in some zones has lead to the dilution of most of metals, it appears that Pb and Mn are associated with this phase. Copper, Zn and Fe are associated with organic matter and detrital particles, whereas Ni and Co are predominantly associated with the insoluble fraction. Oxides/ hydroxides of Fe and Mn are absent because of the reducing conditions and the high terrigenous influx. Geochemically, Mn and Fe are present in different phases of sediments -predominantly in the insoluble fraction and organic matter respectively. The Fe content of one of the cores correlates with the magnetic susceptibility value.

In this work the structure of eddies in the Persian Gulf has been studied, using direct measurements and observations.Using and information records from two Iranian research cruises (Ghods and Ferdows I) have Mt- Mitchell cruises and satellite images, eddies in the Persian Gulf have been recognized. With regard to the interaction between two main circulations in the Persian Gulf, a cyclonic circulation in the southern portion that is driven by density difference from the Strait of Hormuz, and another cyclonic circulation in the north western corner that's driven by Shatt-al-arab and Arvand Roud discharges, the most probability area for eddy formation is the near coastal of Busher Province and the central part of the Persian Gulf. Typical mesoscale eddies with speed of 3-6 cm/s and dominant special scales of about 50 km, which are in the same order as the Ross by radius of deformation in these waters, indicate that baroclinic instability may play an important role in their generation. The transfer of eddies potential energy to kinetic energy is an important process for generating turbulence and instability in the north coastal area near Busher Province.

Sewage stabilization Ponds are basically a number of earthen basins with retention times from a few days to weeks, depending on environmental conditions. Treatment in these lagoons is a natural process, and with proper design, construction, and operation, effluent quality would be suitable for agricultural irrigation from the chemical and biological aspects. An ISP pilot plant which was constructed to the eastern side of Shoosh Sewage treatment Plant in southern Tehran, and included Fermentation Pit Facultative pond, High rate pond and Maturation pond, was put to test and study during March 1999-2000 (Iranian Year 1378). The system was designed for an average sewage inflow of 4 m3/day and 20 days retention time. The sewage flow into the Fermentation pit was kept as up flow in spring, fall and winter seasons and as down flow in summer. To check the efficiency of the treatment process, COD, BOOS, TSS, total Nitrogen, total Phosphorus and fecal coliforms were tested and compared during the four Seasons of operation.The result of the research shows that in spring the global efficiency of the pilot was about 8% better in than summer, which can be attribute to the up flow in pit fermentation. In winter, the removal rate of HOD, COD and TSS were on the average 6% more than in summer, which was due to the role of effluent recycling. This research indicates that the facultative pond with internal pit fermentation has principle role for removal of pollutant (70% removal).Finally, it could be concluded that an ISP system is an efficient process that ensures high treatment of municipal wastewater and reduces detention time in the pond system. It is especially recommended for small to medium size communities.

In the present work a lyophilised cell suspension of Rhgizopus arrhizus was studied as biosorbent material for selenite removal from aqueous solutions.The biomass was firstly characterised by potentiometric titration and evaluation of the major ionic content. The experimental data highlight that the biomass cell wall contains two main acidic groups with a total amount of 5meq/g. Equilibrium biosorption trials of Selenite were carried out to investigate the effects of two important experimental factors, pH and biomass concentration. Selenite biosorption extent was repressed by pH decrease. The effect of the biomass concentration changes both with the equilibrium pH value and the kind of oxyanion adsorbed. In the case of selenite biosorption at pH>5, the increase of biomass concentration causes a diminution of the maximum specific oxyanion uptake, due probably to cell aggregation phenomena. Equilibrium modeling was performed as reported in this paper. Analyses of FTIR showed that selenite adsorbed on extracellular of biomass.

By defining accident, the flow chart of accident was described and the direct and indirect cost of accident was listed. The scenario of a simple accident in which a worker who was carrying some files & documents, fell down in the corridor, was given, the total cost of this accident which was about $5000, was not noted.As a case study the failure of chlorine hose during unloading of a chlorine tanker into a pressurized storage vessel, which is a routine job in the cosmetic and household detergent producing industries, was analyzed. For this event a fault tree was built up. By considering the failure rates of basic events, the failure rate for the top event was calculated to be 4.3x10-3 per year. A cost effectiveness analysis was followed by recommendations of a control measure as an interlock system in one part of the tree. This safety lock would not let the driver move tanker before disconnecting the hose.Application of this control measure in the fault tree decreased the failure rate of top event to 3.1x10-4 per year. This means that the occurrence of one accident in every 2325 years (before application of control measure) will change to one accident in every 3225 years.Assuming the total amount of 500.000.000 Rials as the cost of the accident, understand the annual cost will be 215.035 Rials. After application of the proposed control measure the annual cost will decrease to 155.034 Rials. This means a 60.019 Rials sauing per year due to the proposed control measure.