نشریه علوم و مهندسی آب و فاضلاب
سال هفتم شماره 4 (زمستان 1401)

Currently, many countries, including Iran, are facing extremely high levels of water stress and annually more than 80% of the water available to users is supplied from groundwater resources. Water resources are declining fast, and the picture is alarming in many places around the world. Water resources are part of the common heritage and one of the most basic common natural resources of mankind. Common or public resources are resources for which exclusion of users is difficult to achieve and for which joint use reduces the availability of benefits derived from the resource for others, resulting in condition that produces a competition in the use of resources and the degradation or even destruction of resources. In this article, by using the method of documentary research, the effective factors in the development of cooperative behavior for water conservation using social dilemma theory are described and strategies such as education, moral commitment, communication, punishment and reward and social sanctions for sustainable exploitation of this resource are discussed.

Nowadays, inadequate available freshwater resources, population growth and industrialization of communities have led to the development of various methods for water and wastewater treatment. Different technologies have been used for water and wastewater treatment, among which ultrafiltration membrane with high separation and removal of contaminants is considered as a promising option for water and wastewater treatment. However, membrane fouling is one of the main problems in membrane operation resulted in reduced performance and additional costs. Membrane fouling can be caused by various factors, depending on the type of fouling, different methods can be used to prevent fouling. One way to decrease membrane fouling is to add hydrophilic nanoparticles to the membrane through diverse modification methods. In this review article, we have tried aside from introducing the methods of preparation of anti-fouling membranes, the effects of adding different nanoparticles on the performance and fouling reduction of ultrafiltration membranes through some approaches such as inversion phase, electrospinning, bonding through ultraviolet rays and polymerizations have been discussed.

The main purpose of this study is to investigate the relationship between the components of social capital and the effectiveness of measures being efficient in adapting citizens to the water crisis. In this research, four main components of social capital (including: social trust, social participation, social support and social solidarity) as well as measures being efficient in the water crisis management (including: prevention, readiness, response, and restoration) were examined through the structural equation modeling. The statistical population of the present research that has been a cross-sectional survey, was citizens living in cities and villages of Bushehr province, which were investigated separately. In this regard, two statistical samples of 2000 people (separately for urban and rural residents) were selected and studied based on stratified-relative sampling method (in which each city was considered as a class and the sample was selected in proportion to population). The collected data were analyzed by the structural equation modeling using AMOS22 and SPSS22 software-. Data analysis and research hypotheses test showed that there is a significant relationship between the four main components of social capital and the effectiveness of measures being efficient in adapting citizens to the water crisis. The study results also indicated that the stronger the components of social capital, especially social support and social solidarity, the better the effectiveness of measures being efficient in water crisis management.

Nowadays, due to the large volume of assets in the water and wastewater industry and its impact on the development and sustainability of other industries, specific attention to this industry becomes more apparent. Since there are various equipments in this industry, achieving efficiency and proper performance in this equipment and maintenance system has been identified and then, with fuzzy decision-making which can be envisaged as innovation of this project, the ranking of the factors has been worked upon. The results of this requires timely maintenance and repairs. This study has evaluated the efficiency of these systems by considering the importance of paying attention to the factors that affect the performance of the maintenance system and consequently the quality and reliability. Considering the various evaluation and ranking methods, the present research has investigated this issue in two phases using operations research techniques and fuzzy decision making. In the first, the pivotal factors on the Alborz Province Water and Sewage Company’s function of upkeep study shows that water and sewage companies by employing of technological conditions that include quality and utilization of innovative technologies that have highest priority in comparison to other important alternatives with ultimate importance of 0.3123 could increase productivity.

One of the key areas addressed by the sustainable development discourse is the role of sustainability as a driver of green innovation. The aim of this study was to study the mediating role of company sustainability and sustainability strategies in the relationship between smart technologies and green innovation in companies constructing wastewater treatment plants in the Iran. This research is applicable in terms of purpose and descriptivesurvey in terms of method. The statistical population of the study consists of senior managers of companies designing, constructing and operating municipal wastewater treatment plants, 250 of which were selected using the available sampling method. Findings indicate that intelligent technologies have a significant effect on firm stability and sustainability strategies, and according to the resulting path coefficients with values ​​of 0.74 and 0.31, this relationship is positive and directional. In addition, the results indicate that the sustainability strategy has a significant effect on the stability of the company and the path coefficient with a value of 0.25, indicates a positive and directional relationship. In addition, according to the results of the research, the stability of the company has a significant effect on green innovation and according to the path coefficient with a value of 0.41, this relationship is positive and directional. In addition, the results show that smart technologies have a positive and significant effect on green innovation with the mediating role of company sustainability and the indirect impact of smart technologies on green innovation in this direction is equal to 0.30. Research shows that smart technologies have a positive and significant effect on company sustainability with the mediating role of company sustainability strategy and the rate of indirect impact of smart technologies on company sustainability in this direction is equal to 0.08. In addition, according to the research results, the company's sustainability strategy has a significant effect on green innovation with the mediating role of company sustainability and the indirect impact of the sustainability strategy on green innovation in this direction is equal to 0.10.

Performance accuracy of water meters have a special effect on apparent losses and non-revenue water. The purpose of this paper is investigating the effect of replacing faulty water meters on income generation of water and wastewater companies & encouraging them to replace water meters. 198 water meters from 2 old subscription zones from region 3 of Isfahan were chosen as a sample & replaced in summer 2020. The average monthly consumption one period after replacement was compared with the similar monthly period in last year/years. The results were validated with the results of laboratory test of a number of old water meters of different brands. 35% of water meters had increase in consumption, 13% had decrease in consumption and the average of mean monthly consumption has increased to 26.55%. water meters with the brands 4 had the most negative error. Replacement of water meters reduce the low consumption class and increase the high consumption and misuse class which causes the increase of %67.83 in water rate. The results were generalized to 5928 subscribes of region 3 with over 20 years old water meters. Payback period for replacing all old water meters with the size of 0.5 and 0.75 inch was 4.3 years.