IoT-Based Solid Waste Management Solutions

Abstract

With the increase of population density and the rural exodus to cities, urbanization is assuming extreme proportions and presents a tremendous urban problem related to waste generation. The increase of waste generation has been considered a significant challenge to large urban centers worldwide and represents a critical issue for countries with accelerated population growth in cities. The Internet of Things (IoT) and cloud computing offer an automation possibility through cyberphysical systems that will change the way solid waste management is performed. Considering IoT requirements, a review analysis of waste management models available in the literature is performed in detail in this paper. Then, a deep review is undertaken of the related literature based on IoT infrastructure for efficient handling of waste generated in urban scenarios, focusing on the interaction among concessionaires and waste generators (citizens) from the perspective of a shorter collection time with reduced costs, as well as citizenship promotion. An IoT-based reference model is described, and a comparison analysis of the available solutions is presented, with the goal to highlight the most relevant approaches and identify open research issues on the topic.

Introduction

Waste management is a name given to a waste collection system, including its transportation, disposal or recycling. This term is attributed to waste material that is produced through a human activity which must be handled to avoid its adverse effect for health and for the environment. Most often, waste is managed to reuse available resources. Waste management methods may differ between developed countries, between an urban and a rural environment, or between an industrial and a residential area. The management of waste in metropolitan and rural areas is the general responsibility of a municipality, while waste produced by industries is their responsibility and managed by themselves.

According to data released by the United Nations Department of Economic and Social Affairs, the share of the urban population worldwide is expected to reach 66% by 2050, compared to 52% in 2014, resulting in increased waste production in cities. Data released by the World Bank Group confirm that waste generation rates are growing. In 2012, cities worldwide generated about 1.3 billion tons of solid waste, representing 1.2 kilograms of waste generated per person–day. With rapid population growth occurring along with urbanization, urban waste generation is projected to rise to 2.2 billion tons by 2025, confirming that municipal solid waste (MSW), the main by-product of an urban lifestyle, is growing even faster than the rate of urbanization. This increase in municipal and industrial waste generation, together with stricter regulations aimed at ending illegal waste disposal, stimulate the growth of applications for better waste management. Other factors that have driven the growth of applications designed for the effective management of waste worldwide are directly linked to the constant use of recycling techniques, the cycle of technological innovation, the application of advanced techniques for waste collection, and the use of technologies based on IoT and big data. There is also a vision of strengthening waste management based on public initiatives aimed at building more correct and safer environments, as well as reducing greenhouse gas emissions.

According to Allied Market Research, Portland, Oregon [1], waste management worldwide is expected to grow at an annual rate of 6.2% by 2023, with greater growth in the emerging Asia Pacific region. In Europe, this sector grew by more than 30% in 2016 and growth is expected to continue to accelerate due to the presence of advanced infrastructure and the high demand of several interested sectors. Currently, there are increasing initiatives by governmental and public authorities in relation to waste management to efficiently improve the collection and intelligent disposal of waste generated by a city. These are already considering the accelerated pace of urbanization worldwide and the expansion of the industrial sector, and the manufacturing and healthcare industries that are likely to produce a significant amount of waste and can already be efficiently treated by smart management. Moreover, growth of infrastructure facilities and a rising adoption of advanced waste management systems in developing economies with the goal of using cost-effective and waste–time disposal methods should positively impact the growth of smart management of waste. The great precursor of technological development that has led to innovations in the waste management sector is undoubtedly the advance of the Internet [2]. The Internet has revolutionized the world and offers global connectivity. Similarly, the Internet of Things (IoT) [3] is also set to underpin significant change and represents an Internet evolution known as the next generation of the Internet (i.e., the Fourth Industrial Revolution).

The IoT began with the increasing number of interconnected physical objects providing interactions. The IoT paradigm [4] has a main role as a key facilitator of the integration of various application solutions and communication technologies, such as identification and tracking [5,6], sensor networks, wired and wireless actuators [7], improved communication protocols, and distributed intelligence for objects. According to the Internet Business Solutions Group (IBSG), a milestone of IoT emergence occurred when the Earth’s population was exceeded by the number of objects connected to the Internet, which happened in 2008–2009. IBSG predicts that by 2020, about 50 billion devices will be connected to the Internet [8,9,10,11]. IoT can include a large number of applications designed to assist in many sectors, such as industry, transportation, markets, education, agriculture, healthcare, environment, and smart cities The European Union has defined smart cities (SC) as a system where people interact and use energy, materials, services, and waste to stimulate economic development and improve the quality of life. These interaction flows are considered intelligent because they make strategic use of infrastructures, services, information, and communication in planning urban management, a way to meet the social and economic needs of society. Despite being a relatively recent concept, the smart city topic has already become synonymous with sustainable development within global discussions on sustainability [16]. Currently, cities in emerging countries are investing heavily in smart products and services to sustain economic growth and, at the same time, developed countries need to upgrade existing urban infrastructures to remain competitive. Among the evolutions that have been taking place to classify an intelligent city, a vast range of applications can be listed, such as waste management based on an IoT approach The IoT concept predicts a world in which physical, digital, and virtual objects are interconnected in a network supporting higher order applications. The intelligence of objects comes from the automated data processing of an existing state or the environmental state in which it is immersed. These data are then transmitted to a processing node where they are analyzed, and an appropriate performance profile is determined, considering data acquired from various objects. This actuation profile is then transmitted back to the smart object [22]. The waste management system is included in this context because it has a large number of containers with an inconsistent level of filling that can last from days to weeks, with the possibility of seasonal changes, as well as different emptying requirements, such as distances and type of waste. However, biomedical, chemical, and electronic residues have specific collection points, usually with uniform production and long filling periods.