Waste Management System For City Research Articles

Growing crisis of urban rat infestation in Karaj city, Iran: Insights from hotspot mapping and social network analysis

To control the increasing growth of rat populations in metropolitan areas, several factors need to be considered to mitigate the risks posed by rats. Identifying rat density hotspots with more efficient methods and assessing people's experiences and attitudes toward them can be useful in prioritizing rat control efforts. We focused on the two most common species of rats (Rattus rattus and Rattus norvegicus) in the metropolis of Karaj, the fourth most populous and the largest immigrant-friendly city in Iran. The urban rat infestation is one of the problems caused by the high population growth in Karaj and the insufficient development of urban infrastructure and waste collection. It has led to discontent and public concern about rat infestations and there is a need to address the associated threats. We applied the Kernel Density Function and Optimized Hotspot Analysis to the presence points of the aforementioned types of rats and found that while Optimized Hotspot projects a macro view of hotspots at the city level, the Kernel Density Function prioritizes neighborhoods for initial actions. In addition, social network analysis with complementary regression models was conducted to determine people's experiences. The results show that fear of rats and concern about their presence form the basis of people's attitudes toward rats and lead to feelings of hatred. Moreover, economic harm reinforces people's motivation to control or eliminate this species. Despite their unpleasant feelings toward rats, people have a great influence on the growth of rat infestations by creating food sources through improper waste disposal. They prefer to use traps and poison instead of disposing of household waste and following the principles of cleanliness as preventive measures and believe that the lack of proper garbage collection by the municipality is the most important reason for the growth of rat populations. They are not sufficiently aware of their position in addressing this crisis. Our findings argue for the formation of a stronger network between the relevant authorities and residents, especially those living in the hotspots, to educate them about their role in rat control and to gain their cooperation in improving the city's waste management system.

The potential of urban agriculture in combination with organic waste valorization: Assessment of resource flows and emissions for two european cities

Abstract Large scale urban agriculture (UA) has been considered as a potential contributor to the sustainability and the resilience of the food system. However, its synergy with the tackling of another main challenge in cities, namely the management of organic wastes, has previously not been extensively explored. The aim of this work is to understand the potential of an integrated food-energy-water-waste system in terms of food production, resource circularity and carbon footprint, in comparison with the current food and waste management systems in cities and an UA system without integration with waste management. Employing spatial analysis and a breadth of process parameters and city-specific data, the monthly material and energy flows were simulated and optimized for two European cities, Glasgow and Lyon. The results indicate a strong dependency of food self-sufficiency, waste assimilation and carbon footprint on the ratio between high-intensity greenhouse growing and urban gardening. For a chosen greenhouse to garden ratio of 1:4, the production of a large share of fruit, vegetable and fish supplied with nutrients from waste products and water from rainwater harvesting is theoretically possible, and the integrated UA systems could assimilate 51.7% and 16.9% of food waste in Glasgow and Lyon, respectively. From a food production perspective, co-located waste valorization could reduce the carbon footprint of the UA system by 7.8% for Glasgow and 12.6% for Lyon. However, overall emissions for the integrated UA system are 75.1% (Glasgow) and 4.3% (Lyon) higher than the current system, primarily due to high heating and lighting requirements for greenhouses in winter, even more so in Glasgow which is colder and with a carbon-intensive electricity grid. However, if a UA system is already in place, the decentralized valorization in combination with UA could provide significant emission reduction benefits compared to existing waste-to-energy schemes, in particular for insect rearing in combination with aquaponics. The outcome may inspire urban policy makers and stakeholders to consider the propagation of urban agriculture in symbiosis with decentralized manage waste strategies, in particular in areas with a low-carbon electricity grid, as a move towards self-sustaining cities and a more circular economy overall.

A standardized inspection methodology to evaluate municipal solid waste collection performance

The success of separate collection of municipal solid waste, the efficiency of the other connected services and the justification of a large cost assumed by an authority, depends on the level of service provided to customers as well as the citizens’ attitude towards waste management. In this paper, a semi-qualitative inspection method to evaluate both the door-to-door collection system and the conventional curbside system is proposed. The method is based on the combined evaluation of waste collection using a set of indicators and the assessment of the perception of the citizens towards collection and street cleaning services using behavioural questionnaires. The ultimate goal was to assess potential differences between door-to-door and curbside collection systems. The standardized inspection evaluation method was applied to the city of Reggio, Calabria (Italy), since both collection systems are used there. The standardized inspection evaluation proved to be simple to implement and was effective to accurately evaluate the quality of the service delivered to the citizens. The results of the behavioural survey revealed that citizens that practised door-to-door separation had a higher recycling conscience and were more satisfied with the city waste management system than the ones that practised curbside separation. According to the results of the study, there was a qualitative agreement between the results of the standardized inspection evaluation and the behavioural survey. The door to door collection system is suggested to replace the curbside collection system.

Energy analysis of municipal waste in Dubrovnik

In each touristic city waste management system has to overcome the impact of visitors. Dubrovnik, famous as popular touristic destination, particularly notices tourists visiting city. Therefore potential impact of waste management in touristic cities, such as Dubrovnik, is presented. The paper includes estimation of yearly waste production by inhabitants and tourists visiting those city. Waste digestion is a method for biogas production. On the basis of the preceding estimation combined-cycle installation generating heat and electricity is proposed. The model combines Brayton cycle with low temperature Kalina model based on Rankine cycle. Literature analysis presents state of the art in this field. The simulation is prepared in Cycle-Tempo. Numerical analyses lead to technical issues, which have to be taken into consideration during waste utilization with such installation. Thus benefits and threats are discussed. The presented analysis assesses the maximal electric gain, which subsequently should consider waste preparation and purification

Desafíos en la gestión de residuos sólidos para las ciudades de países en desarrollo

<p class="p1">El manejo de residuos sólidos es un desafío para las autoridades de las ciudades de los países en desarrollo, principalmente debido al incremento en su generación, la carga impuesta sobre el presupuesto municipal como resultado de los altos costos asociados a su manejo, la falta de comprensión sobre una diversidad de factores que afectan las diferentes etapas del manejo de residuos y los vínculos necesarios para habilitar el funcionamiento de todo el sistema de manejo. Un análisis de la literatura sobre el trabajo realizado y reportado principalmente en publicaciones de 2005 a 2011, relacionadas con el manejo de residuos en los países en desarrollo, demostró que pocos artículos brindan información cuantitativa. El análisis se realizó en dos de las revistas científicas más importantes en gestión de residuos, <em>Waste Management Journal </em>y <em>Waste Management and Research</em>. El objetivo de esta investigación fue determinar las acciones y el comportamiento de los actores sociales que juegan un papel en el proceso de manejo de residuos y analizar factores influyentes en el sistema, en más de 30 áreas urbanas en 22 países en desarrollo de tres continentes. En este estudio se utilizó una combinación de métodos para evaluar a los actores sociales involucrados y los factores que influyen en el manejo de residuos en las ciudades. Se recogieron datos de la literatura científica, bases de datos existentes, observaciones realizadas durante visitas a áreas urbanas, entrevistas estructuradas con profesionales de relevancia, ejercicios suministrados a los participantes en talleres y un cuestionario aplicado a los actores involucrados. Se utilizaron métodos estadísticos descriptivos e inferenciales para sacar conclusiones. El resultado de la investigación es una lista completa de los actores sociales involucrados que son pertinentes en los sistemas de manejo de residuos y un juego de factores que revelan las causas más importantes del fracaso de los sistemas. La información brindada es muy útil para la planificación, cambio o implementación de los sistemas de manejo de residuos en las ciudades. </p>

Solid waste management challenges for cities in developing countries

Solid waste management is a challenge for the cities’ authorities in developing countries mainly due to the increasing generation of waste, the burden posed on the municipal budget as a result of the high costs associated to its management, the lack of understanding over a diversity of factors that affect the different stages of waste management and linkages necessary to enable the entire handling system functioning. An analysis of literature on the work done and reported mainly in publications from 2005 to 2011, related to waste management in developing countries, showed that few articles give quantitative information. The analysis was conducted in two of the major scientific journals, Waste Management Journal and Waste Management and Research. The objective of this research was to determine the stakeholders’ action/behavior that have a role in the waste management process and to analyze influential factors on the system, in more than thirty urban areas in 22 developing countries in 4 continents. A combination of methods was used in this study in order to assess the stakeholders and the factors influencing the performance of waste management in the cities. Data was collected from scientific literature, existing data bases, observations made during visits to urban areas, structured interviews with relevant professionals, exercises provided to participants in workshops and a questionnaire applied to stakeholders. Descriptive and inferential statistic methods were used to draw conclusions. The outcomes of the research are a comprehensive list of stakeholders that are relevant in the waste management systems and a set of factors that reveal the most important causes for the systems’ failure. The information provided is very useful when planning, changing or implementing waste management systems in cities.

GHG emissions: an assessment at municipal solid waste disposal site in Indore, India

After ratifying the Kyoto protocol the assessment of anthropogenic greenhouse gases (GHG) inventories has become crucial for India. Municipal solid waste management system for city of Indore, India, has been evaluated for GHG emissions over a period of 41 years. Corresponding assessment of CO2, methane and N2O has been done on the basis of waste quantity and composition assessed for various waste types. IPCC first-order decay model is used for inventory accounting from solid waste disposal site to form the baseline scenario. The inventories thus created are assessed for estimating the energy content and identifying the most appropriate waste processing option by comparing their mitigation potential before landfilling. The impact of improved waste management practices on GHG emissions is quantified. The result shows that though composting can provide 60% mitigation of GHG emissions this is less than the 80% mitigation that can be achieved with an incineration unit.

Inexact fuzzy-stochastic mixed integer programming approach for long-term planning of waste management–––Part B: Case study

In this study, a solid waste decision-support system was developed for the long-term planning of waste management in the City of Regina, Canada. Interactions among various system components, objectives, and constraints will be analyzed. Issues concerning planning for cost-effective diversion and prolongation of the landfill will be addressed. Decisions of system-capacity expansion and waste allocation within a multi-facility, multi-option, and multi-period context will be obtained. The obtained results would provide useful information and decision-support for the City's solid waste management and planning. In the application, four scenarios are considered. Through the above scenario analyses under different waste-management policies, useful decision support for the City's solid waste managers and decision makers was generated. Analyses for the effects of varied policies (for allowable waste flows to different facilities) under 35 and 50% diversion goals were also undertaken. Tradeoffs among system cost and constraint-violation risk were analyzed. Generally, a policy with lower allowable waste-flow levels corresponded to a lower system cost under advantageous conditions but, at the same time, a higher penalty when such allowances were violated. A policy with higher allowable flow levels corresponded to a higher cost under disadvantageous conditions. The modeling results were useful for (i) scheduling adequate time and capacity for long-term planning of the facility development and/or expansion in the city's waste management system, (ii) adjusting of the existing waste flow allocation patterns to satisfy the city's diversion goal, and (iii) generating of desired policies for managing the city's waste generation, collection and disposal.

Inexact Minimax Regret Integer Programming for Long-Term Planning of Municipal Solid Waste Management—Part B: Application

In this study, an inexact minimax regret mixed integer programming (IMMRIP) method is applied to long-term planning of municipal solid waste (MSW) management in the City of Regina. The method can help tackle the dynamic, interactive, and uncertain characteristics of the solid waste management system in the city, and can address issues concerning plans for cost-effective waste diversion and landfill prolongation. Thirty-six situations were examined based on multiple alternatives and scenarios under different waste-generation levels. Reasonable solutions have been generated for decisions of system-capacity expansion and waste-flow allocation, demonstrating complex tradeoffs among system cost, regret level, and constraint-violation risk. Solutions associated with further inexact minimax regret (IMMR) analyses can help tackle tradeoffs between minimized system cost and maximized system feasibility. Under the optimal alternative, the system would reach a maximum reliability with the lowest risks of penalty and wastage. Results provide valuable inputs for adjustment of the existing waste flow allocation patterns to satisfy the city's diversion goals, long-term capacity planning for the city's waste management system, and generation desired policies for managing the city's waste collection and treatment.

An integrated two-stage optimization model for the development of long-term waste-management strategies

In this study, an integrated two-stage optimization model (ITOM) is developed for the planning of municipal solid waste (MSW) management in the City of Regina, Canada. The ITOM improves upon the existing optimization approaches with advantages in uncertainty reflection, dynamic analysis, policy investigation, and risk assessment. It can help analyze various policy scenarios that are associated with different levels of economic penalties when the promised policy targets are violated, and address issues concerning planning for a cost–effective diversion program that targets on the prolongation of the existing landfill. Moreover, violations for capacity and diversion constraints are allowed under a range of significance levels, which reflect the tradeoffs between system-cost and constraint–violation risk. The modeling results are useful for generating a range of decision alternatives under various environmental, socio-economic, and system-reliability conditions. They are valuable for supporting the adjustment (or justification) of the existing waste-management practices, the long-term capacity planning for the city's waste-management system, and the identification of desired policies regarding waste generation and management.

An inexact two-stage mixed integer linear programming method for solid waste management in the City of Regina

In this study, an interval-parameter two-stage mixed integer linear programming (ITMILP) model is developed for supporting long-term planning of waste management activities in the City of Regina. In the ITMILP, both two-stage stochastic programming and interval linear programming are introduced into a general mixed integer linear programming framework. Uncertainties expressed as not only probability density functions but also discrete intervals can be reflected. The model can help tackle the dynamic, interactive and uncertain characteristics of the solid waste management system in the City, and can address issues concerning plans for cost-effective waste diversion and landfill prolongation. Three scenarios are considered based on different waste management policies. The results indicate that reasonable solutions have been generated. They are valuable for supporting the adjustment or justification of the existing waste flow allocation patterns, the long-term capacity planning of the City's waste management system, and the formulation of local policies and regulations regarding waste generation and management.

Long-Term Planning of an Integrated Solid Waste Management System under Uncertainty—II. A North American Case Study

In this study, a solid waste decision support system is developed for the long-term integrated planning of waste management activities in the City of Regina. The system is based on an inexact mixed-integer linear programming model, as described in a companion paper. Interactions among various system components, objectives, and constraints are analyzed. Issues concerning planning for a cost-effective diversion program and prolongation of the existing landfill are addressed. Details related to applicability of the developed system, and interpretation of the modeling outputs is also explicated. In general, six planning scenarios are examined, covering a range of potential system conditions and waste management philosophies. Scenarios 1A to 1C are based on the current practices with the solutions serving as grounds for comparisons with other scenarios. Scenarios 2A and 2B correspond to situations when the existing landfill's life span is to be extended by 5 and 10 years, respectively, indicating that the extension options are feasible as long as a large-scale centralized composting facility is initiated by the start of period 2. If the city is targeting on the diversion goals proposed by the Regina Round Table on Solid Waste Management, scenarios 3A and 3B should be considered, where a new landfill should be located at the northern site once the existing one has been totally consumed. Scenario 3A corresponds to an aggressive diversion strategy while scenario 3B is more conservative. Based on the responses from a number of practicing waste management professionals in the City of Regina, solutions for the six scenarios provide useful decision support for planning the city's waste management system. They may help bring about more cost-effective plans for the regional waste management activities.