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This paper focuses on a comprehensive solution for dry municipal solid waste (MSW) management with describes the scenario of the gasification process. For this purpose, the potential of implementing the MSW gasification process in Southeast Asia (Iran) with three agents of air, steam, and air-steam is investigated. In order to manage the MSW gasification process as accurately as possible in the study area, a thermodynamic, exergy, economic, environmental, carbon footprint, water footprint, ecological emergy, and risk assessment for the three mentioned gasification agents were carried out in the most populated cities of Iran. In the capital of Iran (Tehran) with the largest population and as a result of largest MSW production, the potential of the gasification process has been investigated at different times (10 consecutive years and 12 months of a year). Finally, by combining artificial neural networks and genetic programming, comprehensive relationships have been established to predict the thermodynamic conditions of gasification with an air-steam agent. The general results of the survey indicate that gasification with air agents has good potential for most regions. The use of the steam agent has created worse economic, environmental, and risk conditions than the other two agents. Investigating the potential of the gasification process in Tehran shows that this city has a good potential to implement this process compared to other cities in Iran, and the most suitable location for establishing the gasification process is the 4th region of this city. [Display omitted] • Potential of municipal solid waste (MSW) gasification for all Iranian cities. • Comparison of using air, steam, and air-steam agents for MSW gasification. • The payback period of air agent MSW gasification is lower than other agents. • Machine Learning used for prediction of the behavior of MSW gasification. [ABSTRACT FROM AUTHOR]

The Integrated Solid Waste Management (ISWM) is a recent effective tool to manage with the growing challenge of Municipal Solid Waste (MSW). The ISWM integrates all the system components (i.e. transfer, treatment, recycling and disposal of wastes) to enhance the sustainable waste management whilst reducing operational costs. In this paper, we investigate an integrated framework of the Fleet Size and Mix Vehicle Routing Problem (VRP) to optimize the cost-effective ISWM system. A novel bi-objective Mixed-Integer Linear Programming (MILP) model is developed to concurrently minimize the transportation cost in the entire waste management system and total deviation from the fair load allocation to transfer stations. A complete ISWM system with all interdependent facilities and multiple technologies, is developed to address a tri-echelon Fleet Size and Mix VRP with a heterogeneous fleet of vehicles under multiple technologies and waste compatibility constraints. The model was solved for both the Preemptive and Non-Preemptive conditions using Lexicographic and Goal Programming optimization approaches. The model was tested on a case of ISWM in the Southern part of Tehran, Iran. [ABSTRACT FROM AUTHOR]

This paper proposes a new Vehicle Routing Problem (VRP) with fair Carrier Collaboration (CC) which split multi-pickup and delivery services are considered for serving customers. This study has focused on VRP and serving customers with several commodity requirements from different geographically scattered suppliers subject to constraints on the vehicle capacity. A Mixed Integer Programming (MIP) model to maximize the total profit and the fair sharing of profit among the carriers by considering the travel time minimization is developed. Each carrier with its limited capacity can have reserved requests which must be served by itself and selective requests which can be served by itself or other vehicles or not served at all. There are various applications of the proposed model in the environment which can help reducing number of vehicles serving to the customers and eliminating empty back hauls. A Genetic Algorithm (GA) is proposed to solve this problem due to its Non-deterministic Polynomial-time hard (NP-hard) nature. In addition, Variable Neighbourhood Search (VNS) method is developed for improving the quality of initial solutions. Some instances are generated at different scales to evaluate the algorithm's performance by comparing the results of an exact optimal solution with that of the proposed algorithm. The obtained results demonstrate the efficiency of the proposed algorithm in providing reasonable solutions within an acceptable computational time. The algorithm is also tested for an online shopping website in Tehran, Iran. The test outcome shows that the proposed model returns a better benefit compared to the manual methods. The results of sensitivity analysis suggest that increasing the fairness coefficient among carries can led to a decrease in the total obtained profit. • Develop a novel carrier collaboration routing problem model with multi-commodity service and sharing fair profit. • Extend the carrier collaboration to general problems with in many-to-one problem pickup and delivery category. • Solve the problem with genetic algorithm with a new specific chromosome representation. • Result of implementation of the model in the real-world and sample instances. • Sensitivity analysis of the model based on fair distribution between participants is conducted. [ABSTRACT FROM AUTHOR]

This paper introduces a multi-objective robust optimization model for a municipal solid waste (MSW) management system consisting of customers, transfer stations, landfills, recycle plants, and waste transport vehicles. The proposed model addresses the economic, environmental, and social perspectives of this system simultaneously by minimizing the total cost, the greenhouse gas emission, and the resulting visual pollution, respectively. This model can aid decision makers to locate the optimal sites of MSW recycling and disposal facilities, optimize the capacity allocation of landfills to transfer stations and population centers, optimize the capacity allocation of transfers stations and recycle plants to population centers, determine the most suitable technology for each operation, and find the right number and type of transport vehicles based on aforementioned objectives. Comparing to prior studies, considering all three dimensions of sustainability (i.e. economic, environmental and social) simultaneously, attempting to locate all three major MSW processing and disposal facilities (namely, transfer stations, recycling plants, and landfills) at the same time, and Considering uncertainties involved in this group of facility location problems are the innovations of this study. The proposed model, which is also fully compatible with the waste segregation at source approach, was validated by the use of real data for long-term planning of Tehran's MSW management system by examining five candidate sites for the construction of new facilities. The results show the efficiency of proposed model. [ABSTRACT FROM AUTHOR]

In this study, the efficiency of air cleaners in removal of chemical components of PM 2.5 (PAHs, heavy metals, and ions) in the indoor air of dormitories of Tehran University of Medical Sciences, Iran were assessed. 12 rooms were selected and randomly divided into two groups: sham air purifier system deployed room (SR) vs. true air purifier system deployed room (TR). 24-h PM 2.5 samples were simultaneously collected in both TR and SR on PTFE filter papers at a flow rate of 5 L/min. The results showed overall removal efficiency of 76.5 ± 15.5%, 63.1 ± 22.5%, and 66.2 ± 24.8% for PAHs, heavy metals and ions, respectively. Moreover, the fraction of positive ions decreased when air purifiers were used in the rooms. The results showed that the smoking is an important influencing factor on the indoor air quality; smoking can leads to reduction in removal efficiency of PAHs, heavy metals and ions by 26%, 40%, and 51%, respectively. An air purifier could decreased the PM 2.5 even lower than the WHO annual guideline level in non-smoker rooms. The present study revealed that use of indoor air purifiers can significantly reduce the risk of carcinogenicity and non-carcinogenicity attributed to heavy metals and PAHs, especially in places without a smoker. [Display omitted] • Efficiency of air purifiers (AP) in removal of components of PM 2.5 was investigated. • The results showed removal of 76.5%, 63.1%, and 66.2% for PAHs, metals and ions, respectively. • Smoking leads to efficiency reduction of PAHs, metals and ions by 26%, 40%, and 51%, respectively. • AP could decline the PM 2.5 even lower than the WHO guideline in non-smoker rooms. • AP can significantly reduce the health risks attributed to metals and PAHs. [ABSTRACT FROM AUTHOR]

To reduce the negative impact of the conventional vehicles, governments and authorities try to provide facilities in order to encourage people to use electric vehicles. For this purpose, determining the location and the number of charging stations is of paramount importance. It becomes more challenging when some charging stations cannot provide service due to the disruption or breakdown. In this paper, a bi-objective mixed-integer linear mathematical model for a charging station location problem is developed and solved by Lagrangian relaxation method. Two different chargers that could be installed in the charging stations and budget constraint is considered in the model. To evaluate the applicability of the proposed model on real-world problems, a case study on Tehran is conducted. Based on computational experiments and numerical results, sensitivity analysis on key parameters of the problem is carried out and some helpful suggestions are presented for decision-makers. • A bi-objective region-based model for optimizing CSLP is presented. • Disruption in charging stations is taken into account. • Two different types of chargers and tolerable distance for the users are considered. • The proposed model is implemented in a real-world case study to evaluate the applicability of the model. • Lagrangian relaxation algorithm is used to solve the model and some useful managerial insights are also presented. [ABSTRACT FROM AUTHOR]

Despite the fundamental role of the social aspect in the implementation of sustainability in the bio-based industries, most of the sustainability assessments research have addressed the environmental and economic dimensions. However, the social dimension has been neglected and it can cause an irreparable outcome in the biotechnology industries. Following this issue, this study propounds a modified systemic approach for a social sustainability impact assessment of the treatment technologies for converting waste into bioenergy, based on a review on the common social assessment methods. As it is known, the guideline presented by the United Nations Environment Program (UNEP) and the Society of Environmental Toxicology and Chemistry (2009) due to considering social life cycle assessment has a comprehensive look at the stakeholders. Therefore, in this paper, UNEP method was selected. However, it needs to be modified based on the bio-energy supply chain derived from municipal solid waste. For this purpose, the bioenergy value chain derived from municipal solid waste was designed and combined with UNEP guideline, to complete the level of stakeholder subgroups and the levels of the indicators. The final method of the social assessment system was presented to the board of experts and finalized. In order to design the measurement part of the social assessment system, because of a multi criteria decision making nature of the social sustainability evaluation of the conversion technologies of municipal solid waste to bio-energies, a recent developed multi-criteria decision making method so-called Best Worst Method (BWM) was used in two stages. The criteria are ranked according to their average weight obtained through Best Worst method. One of the major novelties in this research is the way of application of the best worst technique in the second stage. The model was implemented in the case of Tehran as one of the pioneering Iranian municipalities with high potential to produce bioenergy. The results of this study help decision makers to decide where to concentrate their attention during the implementation stage, and to increase social sustainability in their bioenergy supply chains derived waste. [ABSTRACT FROM AUTHOR]

In this paper, the energy, exergy, and economic analysis of a novel integrated power plant is investigated. The novel power plant is integrated by using the heliostat solar receiver, the heliostat solr reciever is integrated with many types of traditional power plants such as the gas turbine cycle, air-bottoming cycle, and absorption refrigeration system. Also, the integration of the heliostat solar receiver to heat the exhaust air from the compressor to reduce the natural gas consumption within the gas cycle has been investigated. For the proposed configurations, energy, exergy, and economic analysis for Tehran, Iran (35.689°N, 51.5°E) has been conducted. The model has been validated using previously published results of other authors. Since the investigated configurations are innovative and to the best of our knowledge a similar whole system does not exist in the literature, each cycle has been validated separately. Results and comparisons are given for six different combinations: gas cycle, gas cycle with air bottoming cycle, and gas cycle with air bottoming cycle and absorption refrigeration system. The previously mentioned cycles are analyzed again but this time with integrating them with heliostat solr reciever. The comparisons study is conducted in terms of monthly average energy efficiency, monthly average exergy efficiency, annual average energy efficiency, annual average exergy efficiency, net present value, simple payback period, payback period, and internal rate of return. Results show that adding the heliostat solr reciever to the different cycles minimizes the fossil fuel consumption and enhance energy performance very significantly, for example the energy and exergy efficiencies are increased from 44% up to 69%. Regarding some economic indicators such as the internal rate of return parameter, the results show that the highest internal rate of return belongs to the combination of the gas cycle with air bottoming cycle and absorption refrigeration system with the value of 0.48 and the combination of the gas cycle combined with heliostat solar receiver has the lowest value of internal rate of return of 0.16. As a result of the reduction in fuel consumption savings and other economic indicators are achieved in addition to better environment impact. Finally, the integration of heliostat solar receiver in power cycles shows many advantages mainly in hot areas where solar radiation is high. [ABSTRACT FROM AUTHOR]

In spite of numerous valuable researches for evaluating the effect of different parameters for analyzing exergy/environmental/economic/energy-matrices/heat transfer of solar stills; the effect of high altitude (highlands) on these parameters and comparing two active/passive systems was not performed. This paper conducted a meticulous analysis of two active and passive solar stills at different altitudes (Tochal: 3964 m and Tehran: 1171 m) during seven consecutive days between 24.07.2018 and 30.07.2018. The geometry of solar stills in both experiments is similar and for active type, the system utilized with thermoelectric (Peltier) modules and powered by a photovoltaic panel. Results revealed that altitude has a direct effect on the exergy of solar stills where the summit-located solar stills (passive and active) have higher exergy efficiency. Furthermore, higher evaporative exergy is obtained by both active solar stills at the Peak of Tochal Mountain and the center of Tehran. Likewise, heat transfer analysis showed that the highest and lowest heat transfer coefficients are obtained by active solar still at the Peak of Tochal Mountain and passive solar still in Tehran respectively. However, due to the higher glass temperature, the highest radiative heat transfer coefficients are obtained by Tehran-located systems. Economic results showed that the highest and lowest cost of water with 0.0079 and 0.0372 $/L are assessed by passive solar still in Tehran and active solar still at the Peak of Tochal Mountain respectively. Energy-matrices indicated that the lowest and highest energy payback time based on energy and exergy with 1.57 and 52.75 years attained by passive solar still in Tehran. Also, Environmental analysis showed that higher CO 2 mitigation obtained by active solar stills rather than passive types in both locations. Also, enviroeconomic as well as exergoeconomic (based on energy) parameters showed that both passive and active SSs at the city of Tehran have higher values rather than that of solar stills at the summit because of higher days of operation during the year. • Exergy efficiency at high-altitude for active/passive solar stills (SSs) is greater than Tehran-located systems. • Higher daily energy/exergy output and evaporation exergy obtained by active SSs. • Highest and lowest EPBT based on energy and exergy with 1.57 and 52.75 years obtained by passive SS in Tehran respectively. • Maximum overall and evaporative heat transfer coefficients (HTCs) are obtained by active SS at the summit of Tochal. • Operation days of the systems has huge impact on Environmental, economic, environeconomic, and exergoeconomic parameters. [ABSTRACT FROM AUTHOR]