Journal of Applied Research in Water and Wastewater
Volume:4 Issue: 2, Summer and Autumn 2017

Supply and maintenance of urban drinking water utilities are the most important priorities of people in the world especially in urban areas and it is very clear for urban planners or decision makers to evaluate the costs of action or weigh them against the problems of inaction. Also, specific annual budget is essential for ensuring people welfare and using water utilities with good quality. There are different issues in relation to managing of urban water utilities in terms of cultural, social, physical, environmental and even political and it is necessary to assess the existing conditions of utility by authorities and experts for making decision about those applications. So, we introduce Performance Benchmarking method for reaching this aim. This method is one of the best and update solutions in analyzing drinking water utility in developed countries especially in United State of America. So, in this paper, seven drinking water utilities of United State have been compared with Tabriz metropolitan drinking water utility that is located in North West of Iran and results of indicators’ performance have been comparatively explained. Also, Results show that Tabriz metropolitan drinking water utilities are low advanced in terms of many indicators’ performance than seven United States drinking water utilities. But, in some indexes almost equal to and in certain other cases are advanced than it. However, this methodology is very effective for decision makers, responsible and other experts in all regions and this model can be applied for other cities and urban areas.

A bench-scale study was designed for removal of Methyl Tertio Butyl Ether (MTBE) and benzene from south of Tehran groundwater. The experiments were implemented on a one-dimensional soil column with similar chemical and physical conditions of the region. Fenton’s chemical oxidation with stabilized nano zero-valent iron particles (S-NZVI) as catalyst was used. For treatment of groundwater polluted with 2 mg L-1 MTBE and 1 mg L-1 benzene, optimum concentrations of H2O2 and S-NZVI were 1500 and 300 mg L-1, respectively. The optimum concentrations led to 78 % elimination of MTBE and 87 % of benzene. Hazardous by-products (acetone and tertio-butyl alcohol) concentrations were less than 0.1 mg L-1, which were considered to be negligible. The soil permeability was reduced to 30 % after removal process. To increase the system efficiency and reduce the consumption of iron, the reaction environment was acidified down to pH = 3.2 led to removal efficiency of 90 % and 96 % for MTBE and benzene, respectively. The scavengers (ions) reduced the system efficiency up to 15 %. This study indicates that theoretically the MTBE and benzene could be removed from groundwater using Fenton’s chemical oxidation with S-NZVI.

The water used in the production process of an agricultural or industrial product is called "virtual water". In Iran with low average annual precipitation also lack of available water resources, concept of the virtual water and its trade is used as a strategy for optimal operation of water resources in many fields such as water scarcity, drought and so on. This concept, also, could hold some interesting new opportunities for the field of sustainable consumption. Recently, in Iran, net virtual water import reached to (15-20)*109 m3 per year and is one out of the top ten virtual importing countries. In this research, after virtual water applicable concepts expressing, virtual water content in some of the agricultural products in the world have been compared with products existence in Iran. Additionally, we selected some strategic agricultural products, which export and import to the country, and used an algorithm called "Genetic Algorithm", to optimize virtual water usage and trade according to demands, agricultural situation, production cost and environmental condition. Results showed which products how could help optimal water resources operation and effect of virtual water usage in economic growth.

Application of N fertilizers in agricultural operations is one of the important sources of nitrate entry into groundwater. In Iran, especially in coastal areas with a high groundwater level, in agricultural areas, there is a risk of pollution of groundwater and surface water to nitrates. This research was conducted with the aim of determining the concentration of chemical parameters of drinking water wells in a Tonekabon village and comparing with acceptable standards. The present study was carried out on groundwater resources of Zawar village of Tonekabon city for six months and then data were analyzed to determine the concentration of chemical parameters and water resources type based on anions and cations in water. The results of this study during the investigation of different wells showed that the total number of samples tested from a drinking water well in Zawar, Tonekabon, the range of nitrate concentration from 8 to 33.7 mg / L, TDS from 233 to 435 mg in liters and the total hardness varied from 211 to 372 mg/L. According to the definition of pollution, the wells were classified in the permitted class in terms of nitrate. However, the approach of nitrate levels in some wells to 20 mg per liter (a sign of the impact of human activities) is also worthy of serious consideration. determining the quality of the area reduces the amount of nitrate in the groundwater and thus increases the quality of groundwater.

Electronic weather stations have increased the availability of weather data for computing hourly and daily reference evapotranspiration (ETo). There is a rational question applied for different climate conditions whether the sum of hourly ETo computation may differ from direct computed daily ETo. In this study for the Kerman area, daily and hourly reference crop water consumption were estimated by the Penman-Monteith equation, using meteorological data collected in one hour intervals by an automatic weather station at Iranian Academic Center for Education, Culture and Research (ACECR), Kerman city, Iran. The direct computed daily evapotranspiration values were compared with the sum of hourly computed evapotranspiration values. Results indicated that there is a distinctive difference between the values as calculated for this experimental station. Based on two tail 95% level t-test, the direct computed daily ETo was greater than the sum of hourly computed ETo. Finally, the relationship of daily and sum of hourly ETo for the study area were presented which can be utilized to compare and convert the computed values.

A bubble curtain is a system that produces bubbles in a deliberate arrangement in water. The technique is based on bubbles of air (gas) being let out under the water surface, commonly on the bottom. When the bubbles rise they act as a barrier, a curtain for prevention of the spreading of particles and other contaminants. In this paper is paid to applications of bubble curtain in protection of environment of offshore. Due to the salt water intrusion in Panama navigable channel is causing environmental damage. Construction of bubble curtains along the channel can be studied as a playbook. In this study, two-phase flow is simulated with simulation software Fluent6.3 for freshwater input from the left, saltwater input from the right, air from several vertical bubbles and water injection. The model is solved by using of two-phase Mixture pattern. For problem solving is used the k-𝜺 turbulence model. The air inlet velocity is considered 0.6 meters per second and again 0.2 meters per second. By using air curtains (bubbles) can be prevented salt water intrusion and the density also be reduced. In this paper the multiphase flow is simulated by computational fluid dynamics method in Panama channel.

Fermentative hydrogen production is a common anoxic process where the bacteria degrade organic matters to produce the required electron in the anaerobic reaction. Dark fermentation in the acidogenic phase utilizing obligated and facultative anaerobes leads to hydrogen (H2) production. This method usually achieves a much higher H2 production rate than other biological processes. The kinetic evaluation of biological hydrogen production using palm oil mill effluent as substrate was done in a modified up-flow anaerobic sludge blanket –fixed film (UASB-FF) reactor. In this study, the two factors of feed flow (QF) (1.7-10.2 l/d) and up-flow velocity (Vup) (0.5-3.0 m/h) were chosen as the independent variables to investigate the bioreactor performance. The maximum specific growth rate (μmax) of hydrogenesis bacteria grown on POME as substrate was obtained at 0.313 d-1 (38 °C). The half-velocity constant (Ks) was 9.04 g/L when POME concentration was 15.0 g/L. In this study, the kinetic parameters of Y, Kd, and k calculated were 0.1 g/g, 0.0043 d-1, and 3.13 g COD/g VSS.d, respectively.