1. Introduction
Waste management is a complex system, entailing different elements (e.g., strategies, infrastructure, logistics, economics, etc.). The decision on which waste management system to implement has direct consequences for the environment, society and economy, elements that are interconnected and that must stay in balance [
1].
Municipal solid waste is a product associated with various human activities, which mostly originates from households (55–80%) and commercial activities (10–30%) [
2,
3].
In the coming years, if people’s lifestyles do not change, which drive the mass production of solid waste, it is expected that its generation will steadily increase [
4]. The main reason for the rapid increase in the rate of municipal solid waste generation and disposal in many cities around the world is modernization and urbanization. Thus, solid waste management has become a major concern in most cities, especially in developing countries [
5,
6]. Consequently, there is an increasing concern about the environmental impacts associated with solid waste management in addition to the increase in costs. For instance, greenhouse gas emissions due to waste disposal, landfilling and management have been recognized as a major contributor to global warming, a worldwide challenge that has to be tackled [
7].
To plan an effective waste management system, accurate projections of the quantities and the composition of the municipal solid waste are required [
8]. Reliable data about the solid waste are unfortunately lacking in many developing countries. Some data are also based on assumptions and not on scientific measurements [
2,
9]. To obtain real and representative data about the generated municipal solid waste, waste characterization is the first step [
10,
11,
12]. Furthermore, the timely identification of variables that influence the generation of MSW will aid in the optimization of efficient waste management. In this sense, forecasting the generation of MSW as a function of the behavior and living conditions of people in a specific urban context should become possible [
13].
In general, understanding the composition of the MSW in a country not only contributes to finding optimized solutions for waste reduction and management but also helps in proposing solutions such as cascade use or resource recovery and recycling, where waste is considered a valuable resource.
In developing countries, the percentage of plastics in municipal solid waste (MSW) streams is on the rise, particularly due to the absence of regulations that limit the application of single-use products and the lack of consumer awareness regarding this waste stream [
14,
15]. Nonetheless, applying solutions that are appropriate for developed countries is not always effective in low-income, rural or infrastructure-limited regions. Therefore, when addressing the challenge of unmanaged plastic waste, we must consider not only technical but also social, ecological, political, and economic dimensions specific to each locality to which they are introduced [
16].
In the state of Palestine, solid waste management is facing many challenges at different levels, legal, organizational, technical, and cultural, in addition to the difficult political situation of limited Palestinian access to and control of lands and resources. About 65% of the MSW is disposed of in sanitary landfills, while the remaining is disposed of in predominantly illegal dumping sites. Despite the success in closing 52 illegal dumping sites, tens more still exist [
17]. Furthermore, the unregulated disposal of waste and the poor recovery of materials at their end of life (EOL) result in loss of resources, loss of land, raised methane and CO
2 emissions, ground water contamination, and fume emissions [
18]. All of these factors can affect health and the environment. As per a press release by the Palestinian Central Bureau of Statistics and the Environment Quality Authority, plastic is one of the most important components of solid waste in Palestine, representing about 16.4% of the total solid waste in the West Bank and about 14.0% of the total solid waste in the Gaza Strip. Despite the tangible amounts of plastic waste, Palestine lacks entities that practice recycling based on their own capabilities, except for the treatments that are ongoing by private operators [
19]. To our knowledge, there is not any literature available about the composition and the quality of the plastic waste in the state of Palestine, with the aim of considering feasible and environmentally friendly solutions.
This study was carried out with the aim of providing significant data to enhance the currently available waste management system, while focusing on the plastic waste fraction in the MSW. The objective was to gather up-to-date data about the generated waste at large and the plastic waste fraction specifically in order to propose strategies to implement an efficient circular economy in the state of Palestine. Defining the abundant polymer types and formats in the plastic waste fraction provides information about consumer behavior, the products most represented, and the possible stakeholders to be targeted when recycling is implemented. The defined solutions—based on the waste quality and characteristics—provide decision makers and the private sector with important foundations on which to plan strategies and business ideas. To achieve these objectives, waste-sorting campaigns were conducted on mixed-waste samples provided by the municipality of Nablus, which were obtained from five different districts with variable characteristics.
4. A Case Study Assessing the Feasibility of MSW Recycling
The organic fraction represents the largest fraction in the collected MSW in Nablus (68%), followed by papers and cardboard (13.6%) and then plastics (10.1%). Given these data, we suggest separating the organic fraction at the source by implementing two different collection containers, one for organic waste and the other for solid recyclables. This will achieve two main aims:
- a.
The recovery of the organic fraction, without contamination, to be used to produce high-value compost for agricultural activities in the country, which could help in replacing chemical fertilizers;
- b.
Recovering paper and cardboard, plastics, metals, and glass in a state where they are easy to sort (automatically or manually) and recycle.
To propose a realistic plan for enhanced waste management, it was important to consider a region (represented with the biggest surrounding cities) and a point where the waste could be transferred to for end-of-life (EOL) treatment. The selected cities are located in the northern to middle part of the West Bank (Nablus, Ramallah, Al-Bireh, Jenin and Tulkarm), with distances to the collection point not exceeding 100 km (see
Figure 9). The population was obtained for these specific cities and not for the surrounding towns, with the intention of having conservative data, to propose correct capacities for the treatment facilities. The population was retrieved from the Palestinian Central Bureau of Statistics for the year 2023 (see
Table 5) [
41]. The traveling distances were calculated between the location of the city center and the eastern side of Nablus, where an industrial zone exists.
As per the data, the total considered population is 397,091. As the average daily waste generation per capita is 1.399 kg (see
Table 3), the yearly generated waste from these cities is calculated to be 202,768.6 tons, following Equation (1).
The yearly production of organic waste is calculated to be 138,693.7 tons (68% of the yearly generated MSW). Assuming that a correct collection of 50% of the organic fraction could be achieved, about 70,000 tons of organic waste could be sent for composting. As organic materials degrade during composting, both the mass and volume of the material would decrease due to the breakdown of structural organic components. In [
42], reductions in mass during composting of windrows were calculated, with an average of 19.4%. Applying this factor, about 55,000 tons of compost could be produced.
The recyclables fraction in Nablus city was ascertained to be 27.4%. In this case study, 55,558 tons of recyclables are produced in 2023, among which 27,577 tons are paper and cardboard. The manufacturing of one ton of paper from recycled fiber is estimated to save approximately 17 trees, 3.3 cubic yards of landfill space, 360 gallons of water, 100 gallons of gasoline, 60 pounds of air pollutants, and 10,401 kW of electricity [
43].
The dry recyclables (excluding paper and cardboard) have to be sent for material recovery facility to separate the polymers.
The plastic fraction was further characterized in this study to propose optimized solutions for its management. Recycling is the preferred option to treat plastic waste. However, when recycling is not the most sustainable option, energy recovery is the alternative [
14]. There are no incineration plants to treat MSW in the state of Palestine. Hence, the plastic fraction is currently dumped or landfilled. If plastics are separately collected together with the dry recyclables, their sorting into the different polymer types would be possible and efficient. Based on the provided data, the total plastic waste generated from the target cities (mentioned in
Table 5) will be about 20,480 tons, while the LDPE, PET, HDPE, and PP polymers will be produced in the amounts mentioned in
Table 6. If losses of 40% during collection occur (assumption), then 60% of the generated plastic waste will be sent for polymer sorting. In the polymer sorting process, further losses will occur due to deficiencies with the state-of-the-art sorting technologies, as well as the complex designs of the materials [
37,
38,
39,
40]. In a study performed on the sorting efficiencies of the different polymers, the following sorting efficiencies were obtained: 72% for films, 84% for PET, 87% for HDPE, and 37% for PP [
44]. Taking these values into consideration, the capacities of potential plastic waste recycling facilities can be estimated (~3500 tons for LDPE and ~2000 tons each for PET and HDPE).
The average recycling efficiencies of the LDPE films, PET bottles, and HDPE and PP rigid recycling processes were considered (values reported in
Table 7 and based on a survey conducted reviewing various recycling facilities in Europe [
44]). Generally, the sorting and recycling rates vary greatly because of the materials’ quality and the number, type, and sequence of technologies used.
As was indicated by the plastic waste characterization conducted in this study, PET bottles and LDPE films are generated in significant amounts. Hence, from the proposed case study and applying the recovery rates and the average recycling rate, an annual production of 2500 tons of LDPE recyclates, 1800 tons of PET recyclates, and 1700 tons of HDPE recyclates could be achieved.
5. Conclusions
Through a detailed analysis of the MSW in Nablus city, this study has elucidated pathways to bolster the current waste management system and integrate the principles of a circular economy. The analysis was based on samples collected from five different districts, ensuring a comprehensive and representative sample.
The organic waste fraction ranged between 64.2% and 73.0% of the MSW (by mass), indicating a significant fraction. The second largest fraction is paper and cardboard (ranging between 12.4% and 15.0%), followed by plastics (ranging between 8.2% and 12.1%). To have a waste management system that is able to minimize landfilled waste and recover resources, the recyclable waste should be efficiently sorted further. The organic waste fraction can be recycled through material recovery and converted into compost used as organic fertilizer. Meanwhile, inorganic waste can be utilized through material recovery and recycling (in a circular economy). Hence, we propose sorting the organic waste at the source by implementing a separate collection container for the organic waste fraction.
Furthermore, the plastic waste fraction was a focus of this study, which was further characterized into the different polymer types and formats. According to the results, the most dominant polymeric types and formats are LDPE films, PET bottles, HDPE rigid, and PP rigid, collectively representing 92.2% of the plastic waste fraction. Hence, we suggest sorting and recycling these fractions.
Based on the outcomes of the waste characterization, a case study was developed to calculate the capacities needed to treat the potentially recyclable waste. As per the proposed model, where conservative collection and sorting efficiencies were considered, about 55,000 tons of compost, 2500 tons of LDPE recyclates, 1800 tons of PET recyclates, and 1700 tons of HDPE recyclates could be produced, where significant amounts are generated within transportable distances.
Additionally, further fractions (paper, cardboard, metals, and glass) could be targeted for recycling. Nonetheless, these fractions were not a focus of this study.
In essence, promoting solid waste recycling is more than just an environmental necessity; it also holds economic, social, and health implications. While this study provides a roadmap for Palestine, its insights, methodologies, and recommendations are poised to benefit regions globally, especially those in the initial stages of establishing or refining their waste management frameworks.