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Background: Internal corrosion and the formation of scale in water distribution pipes are the most important problems for an urban water distribution system. Physical, chemical, or biological factors can lead to these two processes. Internal corrosion and scale formation can impact health, economy, and aesthetics. This study assessed the physicochemical quality parameters and evaluated the potential for corrosion and scale formation in drinking water at the distribution systems of 5 selected cities in Bushehr province (Kangan, Dashtestan, Dashti, Bushehr, and Ganaveh) from 2009-2012. Methods: This study was carried out based on laboratory data collected from monthly samplings of tap water in the Water and Wastewater Company of Bushehr province during the years 2009-2012. Internal corrosion and scale formation rates were calculated using the Ryznar, Langelier, Aggressive, and Puckorius indices. Results: The results of the Ryznar, Puckorius, Aggressive and Langelier indices indicated that the drinking water in the 5 selected cities of Bushehr province was corrosive. Moreover, the majority of parameters used to determine water quality exceeded Iran’s national standards. Conclusion: It is concluded that there is problem of water corrosion and scaling in drinking water of distribution systems in selected cities.

The efficiency of modified Phragmites australis nanoparticles for nitrate removal from aqueous solution in batch and continuous conditions was studied. The effect of different operating conditions such as pH, the amount of adsorbent, and initial nitrate concentration were surveyed. Our results showed that, pH 6 could provide better condition for nitrate removal. The increase in the nitrate concentration from 5 to 120mg L-1 reduced the efficiency from 90% to 67%. Kinetics and isotherm data revealed that the nitrate adsorption successfully can be described by pseudo-second order kinetic model (R2 =1) and Longmuir isotherm (R2 =0.99), respectively. At the continuous-flow mode, column were operated at 0.98 L hr-1 and 2.27 L hr-1 with initial nitrate concentration of 15, 50 and 120 mg L-1. At the above mentioned conditions, the adsorption capacities were 13.4, 28.5 and 36.5 mg g -1 at 0.98 L hr-1 and 25.2, 60.9 and 74.3 mg g-1 at 2.27 L hr-1, respectively.

This study was conducted to determine the efficiency of the up-flow anaerobic sludge blanket (UASB) process in treating the leachate from the municipal solid waste (MSW) in the city of Ahvaz, Iran, under tropical conditions. A pilot scale UASB reactor with a total volume of 30 L was seeded with anaerobic sludge from the sugarcane plant to which diluted municipal leachate was introduced as influent feed. The organic loading rate (OLR) of the reactor was increased from 0.58 to 15 g COD/L.d over a period of 230 days. A maximum COD removal efficiency of 87% was obtained for an organic loading rate of 12 g COD/L.d. The temperature of the reactor was maintained in the range 34-39 ºC during the study period. The maximum reactor temperature (39 ºC) highest reactor temperature (37-39 ºC). The results reveal that the UASB reactor is a feasible one for treating reached was due to the effect of ambient temperature. The highest COD removal efficiency was obtained at the MSW leachates as witnessed by its successful operation in the hot climate of Ahvaz (with an average temperature of 40 ºC over about 7-8 months of the year) and by its potential for receiving and treating high organic loading rates with a high COD removal efficiency (87%). However, an aerobic system must be used after the UASB reactor for the effluent to meet the standards defined for the proposed disposal method.

Disposal of raw municipal wastewater or effluent of preliminary treatment into the sea and ocean is economically more accepted and technically more efficient than secondary treatment. In this method, the wastewater disposed at the bottom of the sea in some points from diffuser. Nowadays, lots of researchers select outfall as a suitable alternative treatment method for coastal cities. The goal of this paper was to introduce the outfall as a wastewater treatment method and its design criteria considering different characteristics of the sea such as salinity, density, temperature, stratification etc. In addition, stagnant sea and thermal stratification is reviewed. In this paper the latest information were reviewed. In this alternative the wastewater treated under dilution, mixing and natural conditions. Moreover, sensitive coastal point are preserved from different wastewater pollutants. Usually, there is no limitation regarding discharge of coliform, DO, BOD, and nutrient concentrations in initial mixing zoom. The parameters such as thermal stratification, salinity stratification, density stratification, marine flows influence design of outfall.

Chitosan is a deacetylated derivative of chitin, which is a naturally abundant mucopolysaccharide, supporting the matter of crustaceans, insects, and fungi. Because of its unique properties, such as non-toxicity, biodegradability, and biocompatibility, chitosan has a wide range of applications in various fields. The objective of the present work is to extract the polymer chitosan from Persian Gulf shrimp shells. In order to determine the physicochemical characteristics of the extracted chitosan, degree of deacetylation, molecular weight, water and fat binding capacities extraction rate, and apparent viscosity were measured using a variety of techniques including viscometry, weight measurement method and Fourier transform infrared spectroscopy (FTIR). The results of the study of the physicochemical properties, molecular weight (6.7×105 Da), degree of deacetylation (57%), ash content as well as yield (0.5%) of the prepared chitosan indicated that shrimp processing wastes (shrimp shells) are a good source of chitosan. The water binding capacity (521%) and fat binding capacity (327%) of the prepared chitosan are in good agreement with the other studies. The elemental analysis showed the C, H and N contents of 35.92%, 7.02%, and 8.66%, respectively. In this study, the antimicrobial activity of chitosan was evaluated against Staphylococcus aureus and Escherichia coli. The results indicated the high potential of chitosan as an antibacterial agent. Moreover, the results of the study indicated that shrimp shells are a rich source of chitin as 25.21% of the shell’s dry weight.