Incineration Innovation: A Path to Efficient and Sustainable Municipal Solid Waste Management in Kuwait

Abstract

Municipal solid waste management has become a critical global issue due to the rapid increase in waste generation driven by urbanization and population growth. This surge in waste poses significant environmental, social, and health challenges, exacerbated by inefficient recycling and waste-to-energy facilities. Effective waste management requires comprehensive strategies encompassing waste reduction, efficient collection, sorting systems, and advanced recycling and energy recovery technologies. This study highlights the potential of incineration as a waste-to-energy solution, specifically focusing on Kuwait. By analyzing various waste management technologies and their applicability, this study emphasizes the role of incineration in transforming municipal solid waste into electricity, thereby reducing landfill use and environmental impacts. The research includes a detailed review of the existing technologies, a case study on Kuwait’s waste management practices, and an evaluation of the economic and environmental benefits of implementing waste-to-energy incineration. The findings underscore the importance of tailored waste management solutions to address specific regional challenges, promote sustainability, and enhance public health and well-being.

1. Introduction

With the rapid increase in municipal solid waste (MSW), waste management has become an urgent global challenge. Urbanization and population growth have led to numerous environmental, social, and health issues, placing tremendous strain on existing waste management systems. The accumulation of waste poses significant threats to both the environment and public health. Additionally, the inefficiencies in recycling programs and waste-to-energy facilities further complicate efforts to reduce environmental impact and promote the sustainable use of resources. As emphasized by Quina et al. [1], addressing these challenges requires comprehensive waste management strategies. Effective waste management necessitates holistic approaches that include waste reduction, the development of efficient collection and sorting systems, and the adoption of advanced technologies for recycling and energy recovery. Although various technologies play a critical role in achieving these objectives, there is a pressing need to improve their accessibility, efficiency, and cost-effectiveness. Anaerobic digestion, a biological process that decomposes organic waste in an oxygen-deficient environment, produces biogas that can be used for electricity generation. This process is particularly well suited to sustainable waste management as it helps mitigate methane emissions from landfills and utilizes renewable energy sources. In many areas, selecting the appropriate technology requires careful consideration of local factors and regulations [2]. The choice of suitable technologies often depends on the type of waste, the state of local infrastructure, and existing regulations. Therefore, selecting the right waste management strategies is essential for enhancing public health, fostering a more sustainable and resilient future, and protecting the environment.

He et al. [3] evaluated thermal separation methods for hazardous Municipal Solid Waste Incineration (MSWI) fly ash, focusing on their effectiveness, economic feasibility, and environmental impact. They also discussed the potential for urban mining from MSWI fly ash, highlighting its environmental and social benefits, even though it may be less cost-effective. Their study helped in identifying the limitations of current methods. Huang et al. [4] enhanced the efficiency of MSWI plants by integrating a solar field, achieving a 15.75% increase in efficiency and generating 16.1% more power. While the MSWI plant’s cost rate decreased by 24.13%, the Levelized Cost of Energy (LCOE) for the solar–MSWI plant was 8.93% lower, demonstrating the effectiveness of multi-objective optimization. Their study also proposed a conceptual solar field design specifically tailored to the conditions of the National Key Laboratory of Environmental Protection’s key technology. Zeng et al. [5] analyzed Tibet’s first MSWI plant under plateau conditions, which has been operational since 2018. Adjustments to the boiler design improved its adaptation to low oxygen levels, and a Life Cycle Assessment (LCA) revealed lower environmental impacts compared to MSWI plants in lowland regions. A Cost–Benefit Analysis (CBA) indicated an 11.97-year payback period and an 8.75% internal rate of return. Additionally, energy analysis showed an 81.92% boiler efficiency, suggesting that MSWI, with minor modifications, is well suited for the Tibetan plateau.

Zhuang et al. [6] addressed challenges in MSWI process control by reviewing the mechanical characteristics and numerical simulation methods of mechanical grates. Their research aimed to support the development of a customized numerical simulation model and a digital twin system for MSWI, emphasizing safety and process optimization. Vilardi et al. [7] conducted a brief exergy analysis of MSWI, examining the effect of increased O₂ concentration in the combustion air. Their results showed a 3% increase in exergy efficiency with flue gas recirculation and clear environmental benefits. However, limited improvements were observed with oxygen-enriched air due to the exergy cost of the air separation unit. Yazdani et al. [8] used energy analysis to compare a conventional natural gas power plant (NGPP) and a Municipal Solid Waste Power Plant (MSWPP). The 3 Megawatt (MW) MSWPP demonstrated a greater renewability, sustainability, efficiency, and overall positive environmental impact than the NGPP.

Ungureanu et al. [9] explored energy recovery from MSW in Maramures County, Romania. Analyzing MSW data and landfill samples, the study concluded that MSW has the potential to generate renewable energy, providing valuable insights for waste management stakeholders in assessing energy recovery opportunities. Xing et al. [10] proposed a system for the pre-drying and torrefaction of MSW to enhance efficiency and reduce pollutants in MSWI. They developed a model to assess the impact on MSWI performance, highlighting improved heating value and energy utilization, offering a concise reference for developing higher-performance MSWI systems. Alzate et al. [11] evaluated the feasibility of waste-to-energy in Colombia, considering various technologies. An economic analysis, factoring in Law 1715 incentives, revealed varied internal rates of return, with notable economic potential in the Andes and Pasto regions, particularly with incentives. Pheakdey et al. [12] assessed the energy potential, economic feasibility, and environmental impact of landfill gas recovery, incineration, and anaerobic digestion in Phnom Penh, Cambodia. Incineration exhibited the highest energy output, economic viability, and positive environmental impact, providing valuable insights for waste-to-energy investments in the country. Cho et al. [13] reviewed the use of MSWI ashes in construction materials, focusing on current practices, engineering properties, and environmental criteria. They identified promising applications in asphalt and concrete, although challenges such as high asphalt binder content and potential gas generation in concrete were also noted. Finally, Yong et al. [14] examined Malaysia’s efforts to harness sustainable energy from the growing MSW volume. Their study focused on MSW-to-energy technologies, addressing challenges like fluctuating waste composition, with the aim of evaluating the sustainability of these technologies in the Southeast Asian nation.

Waste-to-energy (WtE) incineration is a waste management process that involves burning waste at high temperatures. This process not only reduces the volume of waste but also significantly diminishes or eliminates its hazardous properties, while recovering energy in the form of heat or electricity. Although incineration can generate power, it may also release pollutants; however, the environmental impact can be mitigated by using appropriate furnace designs [7]. In the United States, over 70 facilities currently incinerate MSW [8], while Denmark has been advancing WtE incineration technology for more than a century. In Kuwait, 460,000 tons of waste is available for incineration, with this amount increasing by 14,000 tons each year. This waste can contribute to the country’s electricity supply and reduce the need for hazardous solid waste landfill space. It is estimated that each ton of MSW can generate 21 kW of electricity [15], potentially producing 26 MW of electricity daily, which would account for 0.15% of Kuwait’s total electricity production. Economically, this could save the country 6 million Kuwaiti Dinar annually.

The primary aim of this research is to identify the most effective methods for converting waste into energy through incineration in Kuwait. It also emphasizes the importance of conserving landfill space and addressing the associated environmental challenges. To achieve these goals, this study explores new tools and techniques to ensure that landfills properly contain waste while adhering to stringent environmental regulations. By identifying environmentally friendly methods, including incineration, for waste management and energy production, the research seeks to minimize the environmental impact of waste disposal. Incorporating real-world data enhances the study’s credibility and reliability, providing a comprehensive understanding of the challenges and complexities in managing MSW and generating energy. Ultimately, this research aims to provide valuable insights to assist Kuwait’s policymakers, industry stakeholders, and the scientific community in developing sustainable and effective waste-to-energy solutions for the Gulf region.

2. Health Issues Related to Solid Waste

Health issues related to solid waste are driven by various factors, including improper disposal, inadequate treatment, and exposure to hazardous materials. Respiratory problems can arise from inhaling airborne pollutants released during waste decomposition and from the open burning of waste, which emits toxic smoke containing particulate matter, dioxins, and furans [16]. Infectious diseases are also a significant concern, as waste can attract disease-carrying pests such as rodents, flies, and mosquitoes. Individuals handling waste are at risk of contracting diseases through direct contact. Contaminated water sources, caused by leachate from poorly managed landfills, can lead to waterborne diseases like cholera and diarrhea [17]. Additionally, soil contamination by hazardous chemicals and heavy metals from waste can pose long-term health risks, including neurological damage and cancer.

Communities living near waste disposal sites can experience psychological stress and social stigma, while workers in the waste management sector face occupational health hazards, including injuries and chronic diseases due to exposure to toxic substances. For example, in India, the challenges many urban areas face in managing waste have led to garbage accumulation in streets, waterways, and other public areas. This has resulted in pollution and the contamination of food and drinking water, as well as air pollution from residents burning trash for heat, electricity, and other purposes. As highlighted in the study by Cheela et al. [18], improper waste treatment and disposal practices in India have resulted in significant environmental and health challenges, particularly in densely populated urban areas.

Similar issues are observed in Nigeria, where the government’s inability to effectively and consistently manage waste poses a serious threat to public health, leading to an increase in diseases such as malaria, cholera, dengue fever, diarrhea, Lassa fever, and respiratory illnesses. Gowda et al. [19] emphasize that waste workers in these regions face high risks due to direct exposure to hazardous materials, which can result in severe health consequences, including chronic respiratory conditions.

These health issues underscore the critical importance of proper solid waste management to protect public health and the environment. Although the incineration of MSW for power generation has been associated with several health issues, the risk is far less than from discarding MSW in open landfills.

Kuwait’s population faces various health risks linked to environmental factors and landfill, including respiratory issues, cardiovascular diseases, cancer, skin diseases, birth defects, and neurological effects [20,21,22,23,24]. Respiratory disorders account for 8.66% of health concerns, while cardiovascular diseases, the most significant category, represent 13.28%. These statistics highlight the serious public health risks associated with exposure to contaminants from landfills. These data are derived from the Global Burden of Disease [25] which provides comprehensive information on the health consequences of environmental factors in Kuwait. Hazardous pollutants such as methane, volatile organic compounds, and heavy metals found in landfill emissions can negatively affect health, especially for those living near landfill sites. The increased prevalence of respiratory and cardiovascular illnesses underscores the need for improved waste management protocols and stricter environmental regulations. Figure 1 illustrates the prevalence of health problems associated with environmental pollution, further supporting the shift from traditional landfill waste management to more environmentally friendly WtE methods. Reducing reliance on landfills can lower exposure to harmful pollutants and improve the overall health outcomes of the population.

Given the large presence of MSW in Kuwait and the scarcity of land, incineration emerges as a crucial option, requiring minimal adjustments to the country’s existing power stations. However, to meet air quality standards and control the release of harmful gases and particulates, it is necessary to install specialized equipment such as scrubbers, filters, and electrostatic precipitators. These devices are essential for minimizing pollutants and ensuring that the residues left after incineration do not release harmful substances into the environment [26]. While Kuwait has made strides in air pollution monitoring by establishing air quality stations throughout the country, particularly around power stations and the oil industry, more efforts are needed to address the growing landfill issues. Although there is limited research on Kuwait’s waste management strategies, this research aims to explore the potential of implementing incineration technology in the country. Additionally, innovative approaches to MSW management such as recycling and advanced residue treatment for establishing a sustainable and environmentally friendly waste management system in Kuwait are discussed [27].

3. Waste-to-Energy (WtE) Technologies

Figure 2 provides a visual representation of the key differences among WtE technologies, with a specific emphasis on the variety of waste they are capable of handling, the level of technological complexity involved, and the influence they have on the environment. Incineration and anaerobic digestion, which have lower complexity, are capable of managing a wider range of waste types and various waste streams. According to Khoshnevisan et al. [28], anaerobic digestion is an effective method to produce biogas with minimal emissions, particularly with regard to organic waste streams. However, this approach has several limitations, such as the requirement for specialized infrastructure and organic feedstock of high quality. Molino et al. [29] outlined gasification as an alternative that is more adaptable since it turns MSW into syngas, which has dual uses: as a chemical feedstock or as an energy source. Nevertheless, as Sharuddin et al. [30] have noted, Pyrolysis is frequently more appropriate for specific categories of waste, such as plastics and biomass, than the mixed waste stream that is typical of urban environments. Additionally, the energy output is generally lower than that of incineration, and the technology is still in the process of evolving.

The suitability of each WtE technology is usually evaluated based on key factors including waste stream compatibility, energy recovery potential, infrastructure requirements, environmental impact, and implementation feasibility. Incineration scored highest overall due to its ability to handle mixed waste with minimal pre-treatment, its substantial energy recovery potential, and the fact that it can be implemented using existing infrastructure with advanced emission control technologies. Given Kuwait’s urgent need to reduce landfill reliance and generate energy, incineration presents itself as a particularly suitable option. While other WtE technologies offer various advantages, the flexibility and scalability of incineration, combined with its ability to handle mixed waste and generate substantial energy, make it an ideal choice for Kuwait’s specific waste management challenges.

4. Landfill and Solid Waste Management in Kuwait

Kuwait MSW, among other wastes, is managed at three locations: Jahra, 7th Ring Road, and Mina Abdullah. The waste disposal process involves digging a hole approximately 20 to 25 m deep, into which garbage trucks unload their contents. Specialized heavy machinery is then deployed into the excavation site to roll over and compress these wastes, reducing their volume. Next, sand is deposited over the compacted wastes to mask odors and deter the spread of flies and insects. Finally, heavy machinery is used to level the dumped sand, with this procedure repeated many times until the hole is filled and level with the surrounding ground. This process, which first began in 1961, presently occupies 22 km² of land mass, and as MSW increases in Kuwait, the needed land is expected to increase roughly 2–3% annually. Based on statistics from the Kuwait Central Statistical Bureau (CSB), Kuwait produced nearly two million tons of MSW in 2021 alone, Figure 3 [32].

In Kuwait, each person generates an average of 1.3 kg of waste per day, nearly double the global per capita average of 0.74 kg per day [33]. This highlights the urgent need for sustainable waste management solutions, which can be achieved by addressing the environmental issues discussed in the previous section. Evidently, there is the need for sustainable solutions to this problem, which are achievable by examining the environmental problems that were addressed in the previous section. Biological materials break down in landfills, polluting groundwater and releasing methane that contributes to climate change. In fact, methane contributes to climate change at a rate that is 25 times greater than that of carbon dioxide, and its atmospheric concentration has been increasing roughly 1 to 2% per year [34]. One ton of decomposing organic waste can release 50–110 m³ of carbon dioxide and 90–140 m³ of methane [35]. Given the quantity of organic materials dumped into Kuwait landfills, it can reasonably produce 257,000 m³ of methane daily, enough to produce 16 MW of clean and free energy. Finally, waste-to-energy systems like anaerobic digestion help reduce methane emissions from landfills and produce green energy.

The significant social and environmental challenges resulting from the disposal of MSW in open landfills necessitate the Kuwait government taking effective action to address the problem. In 1975, cleaning companies in the residential area of Qurain exploited pits designated for recycling and extracting building materials by backfilling them with various types of waste, including MSW. This continued until the pits were filled with waste after about ten years. When the Qurain Housing Project was initiated in 1989, it was discovered that the waste extended into the project boundaries, leading to unpleasant odors, frequent fires, and excessive methane gas emissions due to bacterial decomposition [36]. The improper disposal of MSW also results in other serious environmental issues. One major concern is groundwater pollution, which occurs when waste leaches into underground cavities. Additionally, the spread of insects, rodents, and diseases in landfill areas poses public health risks. Fires, whether accidental or deliberate, represent a significant threat to the environment. The high financial cost and risks associated with reclaiming landfill sites also present challenges for both individuals and the government. Given that only 25% of Kuwait’s land is available for public use, with the remaining 75% owned by the government and the petroleum sector, the growing population and ongoing land development strategies will make it increasingly difficult to secure land for future housing and public services.

5. MSW Composition in Kuwait

MSW in Kuwait includes organic matter, recyclables, and combustibles. Proper management, such as recycling or landfill disposal, is crucial due to the emissions associated with waste decomposition. Figure 4 shows the types of solid waste in Kuwait, as based on a recent UN study [37]. According to the study, 47% of the waste is organic matter, while paper, fabric, and non-organic material constitutes 28%. By determining the heating value of the combustible material, real data can be used to estimate the amount of produced power.

Table 1. The quantities of various waste types generated in Kuwait between 2004 and 2019.

Year	Construction Waste (Ton)	Population’s Solid Garbage (Ton)	Liquid Garbage (Gallon)	Agricultural Garbage (Ton)	Commercial Garbage (Ton)	Medical Waste (Kg)
2004	4,309,200	840,005	1,107,435,000	80,383	187,561	-
2005	4,835,040	851,865	1,081,507,000	78,386	182,902	-
2006	8,914,794	987,295	2,000,840,000	90,325	210,759	-
2007	7,389,716	1,020,610	829,493,100	166,922	389,486	-
2008	6,895,306	1,310,036	732,171,690	259,409	605,287	-
2009	6,658,413	1,153,230	1,113,781,440	171,128	399,300	1,994,483
2010	7,243,231	1,408,432.5	801,034,800	174,435	3,597,56	1,245,129.212
2011	9,414,857	1,357,395	859,476,060	142,752	333,740	2,591,846
2012	9,463,941	1,425,023	927,052,700	132,267	371,356	2,814,600
2013	9,878,681	1,487,265	644,053,500	181,461	349,576	3,133,521
2014	12,078,852	1,490,235	554,354,861	265,725	341,812	3,555,019
2015	10,378,027	1,527,877.5	450,645,125	368,934	364,620	2,947,730
2016	11,810,325	1,567,965	406,409,000	403,431	353,808	3,890,370
2017	15,851,493	1,696,923	422,955,437	437,832	411,896	4,955,389
2018	12,679,097	1,786,079	389,297,357	453,667	485,712	7,010,654
2019	15,743,415	1,857,840	413,333,500	337,293	7,30,340	6,648,976

provides a complete list of the different types of waste found in Kuwait from 2004 to 2019 [32]. The data clearly indicate that construction waste comprised the highest percentage of the total waste during this period. Construction waste is reusable and does not cause grave harm to the environment. As for medical waste, it was the lowest among all the categories, with an average of 3700 tons, demonstrating how little medical waste is produced compared to waste from other businesses. In fact, Kuwait produces a total of 1,360,505 tons of solid waste every year, which includes waste from businesses and farms. Solutions are, therefore, needed to transform solid waste into electricity by incineration, which can ease the load on landfills and address long-term energy needs.

Figure 5 provides a comprehensive overview of the evolution of solid waste growth in Kuwait from 2004 to 2019. The data clearly depict a consistent upward trajectory during this period. Specifically, there is a notable contrast in the rate of increase between two distinct time periods. From 2004 to 2011, the annual growth in solid waste production was substantial, averaging 42.3%. This period is characterized by a rapid and significant rise in waste generation. In contrast, the years 2012 to 2019 exhibit a more stable trend, with an average annual increase of 11.75%. This later period reflects a more moderate and consistent growth pattern compared to the previous years, suggesting potential shifts in waste management practices or environmental policies during this time.

6. Minimizing Landfill Impact in Kuwait through Recycling

MSW contains recyclable materials, food residues (organic), paper, metal, glass, and other materials. Recyclable materials can be collected and sold to local manufacturers or shipped outside the country and sold to the global market, which is considered as a source of income for the country. Based on international prices for recyclable materials as shown in

Table 2. International prices for recyclable materials [39].

Recycle Material	Piece (US USD/ton)	Expected Annual Revenue for Kuwait (USD)
Plastic	309	123,600,000
Steel	29	870,000
Glass (amber)	28	1,960,000
Paper	6	2,400,000
Total annual revenue (USD)		128,830,000
Annual Reduction in Landfill Usage (km2)		0.14

, Kuwait can generate revenue that may help cover the costs of waste-handling companies. When the government opts not to pursue either option, a third alternative is to dispose of organic and other materials in landfills. In landfills, these materials undergo bacterial decomposition, volatilization, and chemical reactions, resulting in the production of 45–60% methane and 40–60% carbon dioxide [38]. The time it takes for methane gas to generate depends on many factors, such as site depth, MSW quality and quantity, the percentage of organic materials, the site temperature, and the humidity of these wastes. Regardless, the landfill will emit gases for more than 10 years, even though peak gas production typically occurs 5 to 7 years after the waste is buried.

As previously shown in Figure 4, plastics, paper, metals, and glass collectively constitute 45% of Kuwait’s total solid waste and are categorized as recyclable materials suitable for reuse or selling. If a recycling approach or selling to the international market had been implemented in the country, then over 2 km² of land could have been saved between 2004 to 2019, as shown in Figure 6. However, if the recycling method or selling recycling materials internationally is applied from this year until 2050, the potential impact in terms of saving land is over 3.5 km². This area is roughly equivalent to the size of a suburb in Kuwait, highlighting the significant potential impact of implementing recycling practices on reducing landfill use over time.

7. Minimizing Landfill Impact in Kuwait through Incineration

The incineration of MSW conserves land space by significantly reducing the volume of waste, typically converting it into ash that constitutes only 10–20% of the original mass. This process diverts large quantities of waste from landfills, thereby extending the lifespan of existing landfill sites and reducing the need for new ones. In regions with limited land availability, like Kuwait, this is particularly beneficial as it prevents the extensive use of land for waste disposal. Additionally, incineration lowers the amount of biodegradable waste in landfills, cutting down on the production of harmful landfill gases like methane. The residual ash can also be repurposed in construction, further minimizing the need for landfill space and contributing to more sustainable land use. Had incineration been implemented between 2004 and 2019 for all recyclable materials and food wastes, approximately 4.1 km² of landfill space could have been conserved, as shown in Figure 7. Projecting this trend forward, if incineration is adopted in 2024, it is estimated that by 2050, around 7.5 km² of landfill space could be saved.

8. Minimizing Harmful Emissions by Incineration

The comparison between MSW incineration and conventional crude oil power plants highlights the environmental benefits of incineration-based WtE systems. As illustrated in Figure 8, crude oil power plants generate significantly higher emissions than modern incineration facilities. For instance, crude oil plants emit an average of 477–714 kg CO₂ per MWh, significantly more than the 300–500 kg CO₂ per MWh emitted by incineration plants [40,41]. Additionally, NO_x emissions from crude oil plants range from 1.7 to 3.5 kg/MWh, whereas incineration facilities emit only 0.7–1.2 kg/MWh. Similarly, SO_x emissions from crude oil plants can reach up to 2.9 kg/MWh, compared to 0.5–1 kg/MWh from incineration facilities.

Comparing life cycle emissions reveals greater environmental benefits from transitioning to incineration. Reducing the reliance on landfills helps mitigate global warming by avoiding methane emissions, which has higher impact than CO₂, while replacing crude oil power generation with a WtE system based on incineration would lead to significant cumulative reductions in emissions over several decades, particularly in CO₂, NO_x, and SO_x. To further safeguard public health and the environment, modern incineration facilities are equipped with advanced air pollution control technologies, such as scrubbers and filters, ensuring that emissions remain well below regulatory limits. This environmental evaluation establishes that incineration is a feasible option for regions such as Kuwait, where a variety of waste streams and the pressing requirement for waste management solutions coincide with energy needs.

9. Waste Management Procedures

As Kuwait seeks to enhance its waste management practices, exploring innovative approaches becomes imperative. This paper suggests a promising strategy: the implementation of a comprehensive incineration-based waste management system. This idea aims to improve efficiency, reduce environmental impact, and align with the country’s Vision 2040. The proposed strategy covers all stages of waste management, from collection and transportation to energy recovery, ensuring a holistic and sustainable approach. The detailed process steps are depicted in Figure 9.

9.1. Collection and Transportation

Trash collection in Kuwait is managed by the Kuwait Municipality or waste collection companies. Various types of MSW, including general trash, recyclables, and organic waste, are collected from residential, commercial, and industrial areas. These waste types will be placed in separate bins for homes and businesses, which will then be transported to central transfer stations or treatment facilities. At these waste transfer sites, the trash will be gathered and sorted before being sent to its final disposal or treatment facilities. Additional sorting and categorization may also occur at these locations to streamline the handling process. Modern waste management systems in Kuwait will often incorporate tracking and management technologies to monitor waste movement, optimize collection routes, and allow authorities to track waste volumes and ensure appropriate treatment methods. Local governorates, municipal departments, and waste management agencies will provide the most up-to-date and specific information on trash collection and transportation in Kuwait.

9.2. Waste Sorting and Preparation

Significant emphasis is placed on sorting and preparing MSW before collection to improve efficiency and minimize the environmental impact of waste processing. In this critical phase, waste will be meticulously sorted to identify recyclable items and separate them from potentially hazardous or dangerous materials. Specialized sorting facilities will further divide waste streams into various components, enabling the effective separation and processing of recyclable materials. This practice will contribute to long-term waste management goals and reduce the release of harmful substances during subsequent treatment processes, thereby supporting environmental protection. Waste sorting will be a top priority in Kuwait, underscoring the country’s commitment to environmentally responsible municipal solid waste management.

9.3. Incineration

In this phase, processed and sorted waste is incinerated in specially designed incinerators under strict supervision. These incinerators will operate at high temperatures to ensure thorough and efficient combustion. The organic components of the waste will be converted into ash, while the resulting heat will often be used to generate steam for energy production or various heating purposes. Controlled incineration will not only reduce the volume of waste but also enable energy recovery, aligning with Kuwait’s goal of achieving long-term benefits from its waste management practices. The combustion process will adhere to environmental regulations to support Kuwait’s Vision 2040.

9.4. Air Pollution Control

This phase focuses on mitigating air pollution resulting from incineration. When waste is burned, harmful gases and particles are released into the air. To comply with air quality regulations, incineration facilities will utilize advanced technologies such as scrubbers, filters, and electrostatic precipitators to control pollution, thereby minimizing emissions and reducing their negative impact on health and the environment. As highlighted by Vehlow [40], air pollution control systems are essential in keeping these emissions within safe limits, thus reducing potential long-term environmental impacts. Kuwait can make significant strides in this area by implementing advanced air pollution control technologies, demonstrating its commitment to responsible waste management and adherence to air quality standards.

9.5. Residue Handling

The incineration of MSW produces residue that must be safely managed to protect human and environmental health. While not all residues will be toxic, strict regulations must be followed by those responsible for handling them. For example, certain types of ash can be safely disposed of in controlled landfills. Although this aspect has been largely overlooked by scholars, Kuwait’s waste management strategy can employ various methods to handle and dispose of incineration residues, ensuring both safety and compliance with environmental standards.

9.6. Energy Recovery

Energy recovery is the final stage of MSW incineration. Modern incinerator plants will capture the heat generated during combustion to produce steam, which can be used for power generation or various heating purposes. This approach aligns with Kuwait’s goal of utilizing sustainable energy sources, while minimizing the environmental impact of waste disposal. By converting thermal energy from waste into usable energy, Kuwait will enhance its resource efficiency and sustainability, contributing to a circular economy.

10. Estimation of MSW Energy Using Mathematical Models

Determining the higher heating value (HHV) of MSW can be achieved through either experimental methods or mathematical models. Experimental approaches typically use a bomb calorimeter with a 1 g sample size, which may not fully capture the broad variability in MSW composition [42,43,44,45,46]. In contrast, mathematical models offer an alternative by reducing the reliance on time-consuming experimental procedures. These models are developed using data from the physical composition, proximate analysis, and elemental analysis of MSW.

Proximate analysis models are based on the weight percentages of volatile matter and fixed carbon in MSW. These sample sizes are more representative of the total MSW compared to the smaller samples used in experimental methods with a bomb calorimeter (maximum of 1 g) or in elemental analysis (1–5 mg). An alternative approach to estimating the HHV of MSW using mathematical models involves analyzing the physical composition of the waste, which entails separating MSW into different components such as food, paper, plastics, glass, and metals. This method provides a detailed breakdown of the material types present in the waste stream and aids in assessing the potential energy recovery from MSW [42]. However, it is important to note that mathematical models are typically most accurate within the country where they were developed and may provide inaccurate predictions when applied internationally [43]. In this study, due to the inaccessibility of the required devices for proximate and elemental analysis, a range of commonly used physical composition models will be investigated and compared to estimate the energy potential of MSW as a fuel, as shown in

Table 3. Most used equations based on physical components of MSW for finding HHV.

Equation	Equation No.	Unit	Condition
HHV = 112.15FW + 183.386P + 288.737PL + 5064.701	(1)	kJ/kg	Wet
HHV = 81.209FW + 285.035P + 8724.209	(2)	kJ/kg	Wet
HHV = 112.15FW + 184.366P + 298.343PL − 1.920M + 5130.380	(3)	kJ/kg	Wet

FW: food waste (wt%); P: paper and cardboard (wt%); PL: plastics or plastics and rubber (wt%); M: moisture (wt%).

below.

In the previous literature [42,43,44,45,46], the contents of MSW were segregated to find the percentage of all the physical components in the MSW. Then, these mixed contents were ignited in a bomb calorimeter to find their HHV. Finally, a comparison was made between the experimental results and the data obtained mathematically using physical components; proximate and ultimate analysis were performed. It was found that the proximate and ultimate analysis results yielded the most accurate estimation of the HHV. However, mathematical models (Equations (1)–(3)) based on physical components tend to vary significantly compared to experimental results. This was also true with the work of Kathiravale et al. [43], which concluded that all mathematical models created in the study and based on local MSW performed better than other equations created for MSW in other parts of the world. This illustrates that an equation for the prediction of the HHV of MSW is best suited to its own area of study. In other words, it is difficult to devise an equation that is suitable for predicting the HHV of MSW in different parts of the world.

These equations were developed using multiple regression analysis. Previous studies [4,42] indicate that the moisture content in MSW ranges from 38% to 55%. Plastic is the most significant energy source in MSW, with an average energy content of 38 MJ/kg, while paper has an average energy content of about 17 MJ/kg [44]. As shown in Figure 4, plastic and paper each constitute 20% of the total MSW in Kuwait, with food waste being the dominant component. Applying Equations (1)–(3) from Table 3 to Kuwait’s MSW statistics, the HHV was found to range from 18 to 20 MJ/kg. The impact of moisture on the predicted energy value is minimal due to its small coefficient in the equations. The mathematical model equations presented in Table 3 are derived from multiple regression analysis, which identifies the optimal coefficient values to fit experimental data. However, these coefficients do not account for the type of physical component within MSW. Consequently, this study aims to develop a mathematical model based on two assumptions: first, the HHV of MSW is the sum of the fractions of each physical component within the MSW multiplied by its HHV, as shown in Equation (4); second, only combustible materials within the MSW, including food waste, will be considered in the new model.

$$\mathbf{M}\mathbf{S}\mathbf{W}\left(\mathbf{H}\mathbf{H}\mathbf{V}\right)=\left(\mathbf{\%}{\displaystyle \frac{\mathbf{F}\mathbf{o}\mathbf{o}\mathbf{d}}{\mathbf{100}}}\right).\mathbf{H}\mathbf{H}\mathbf{V}+\mathbf{\%}\mathbf{P}\mathbf{l}\mathbf{a}\mathbf{s}\mathbf{t}\mathbf{i}\mathbf{c}.\mathbf{H}\mathbf{H}\mathbf{V}+\left(\mathbf{\%}{\displaystyle \frac{\mathbf{P}\mathbf{a}\mathbf{p}\mathbf{e}\mathbf{r}}{\mathbf{100}}}\right).\mathbf{H}\mathbf{H}\mathbf{V}+\left(\mathbf{\%}{\displaystyle \frac{\mathbf{W}\mathbf{o}\mathbf{o}\mathbf{d}}{\mathbf{100}}}\right).\mathbf{H}\mathbf{H}\mathbf{V}+\left(\mathbf{\%}{\displaystyle \frac{\mathbf{Y}\mathbf{a}\mathbf{r}\mathbf{d}}{\mathbf{100}}}\right).\mathbf{H}\mathbf{H}\mathbf{V}+\left(\mathbf{\%}{\displaystyle \frac{\mathbf{R}\mathbf{u}\mathbf{b}\mathbf{b}\mathbf{e}\mathbf{r}}{\mathbf{100}}}\right).\mathbf{H}\mathbf{H}\mathbf{V}+\left(\mathbf{\%}{\displaystyle \frac{\mathbf{T}\mathbf{e}\mathbf{x}\mathbf{t}\mathbf{i}\mathbf{l}\mathbf{e}}{\mathbf{100}}}\right).\mathbf{H}\mathbf{H}\mathbf{V} (\mathrm{MJ}/\mathrm{kg})$$

(4)

From the literature [42,43,44,45,46], the HHV for different physical components of MSW can be summarized as presented in

Table 4. HHV range for most common physical component of MSW.

No.	MSW Physical Component	HHV (MJ/kg)
1	Food Waste	5.5–38
2	Plastic	30–45
3	Paper and Cardboard	14–17
4	Wood	16–21
5	Yard Waste	14–23
6	Rubber and Leather	25–33
7	Textile	14–20

.

Since bomb calorimeter tests were not feasible for Kuwait’s MSW, a new mathematical model was developed. To validate its accuracy, the model’s predictions were compared with experimental data from various research papers where bomb calorimeter tests had been conducted on similar materials. Using multiple regression analysis, the model incorporated all MSW components listed in Table 4, along with their respective fractions, based on data from the literature [42]. Initially, the HHV for all components was unknown and was determined through the regression process. The predicted HHV values are presented in

Table 5. Estimated HHV for various MSW components based on multiple regression analysis.

No.	MSW Physical Component	HHV (MJ/kg)
1	Food Waste	15
2	Plastic	46
3	Paper and Cardboard	20
4	Wood	19
5	Yard Waste	14
6	Rubber and Leather	25
7	Textile	22

.

The new model was validated using data from the literature [44]. In this study, MSW from Jimma City was monitored over a full week. The results of this validation are summarized in

Table 6. Percentage of physical components of MSW in Jimma City [44].

No.	Food	Yard	Wood	Paper	Plastic	Rubber and Leather	Textile
Monday	30.5	25.7	4.3	8	13.06	2.14	5.33
Tuesday	26.3	24	5.3	8.7	13.3	2.9	5.3
Wednesday	39.1	22.8	2.8	7.5	10.5	3.47	5.73
Thursday	28.5	24.8	4.7	7.1	14.5	3.43	5.63
Friday	32.2	27.8	3.86	8.5	13	2.13	4.9
Saturday	34	28.4	3.43	8.55	9.6	3.42	6.1
Sunday	35.3	29	2.4	7.72	9.11	3.46	6.38

.

Using the three physical mathematical models (Equations (1)–(3)) for predicting the HHV in MSW, the new model exhibits superior performance compared to the other three physical component equations, as illustrated in

Table 7. Comparison between experimental and predicted results based on physical components from Jimma city [44].

No.	Lab Results (MJ/kg) [45]	New Model (MJ/kg)	Variation %	Equation (1) (MJ/kg)	Equation (2) (MJ/kg)	Equation (3) (MJ/kg)
Monday	18	18.3	−1.7%	13.7	13.5	13.8
Tuesday	17.85	18.1	−1.5%	13.4	13.3	13.6
Wednesday	17.45	18.1	−3.1%	13.9	14.0	14.0
Thursday	17.85	18.9	−5.8%	13.7	13.1	13.9
Friday	17.65	18.8	−6.5%	14.0	13.8	14.1
Saturday	16.75	18.1	−8.1%	13.2	13.9	13.3
Sunday	16.35	17.8	−9.3%	13.1	13.8	13.1

.

The variation between lab results and the new model’s predictions ranged from a minimum of 1.5% to a maximum of just over 9%. Additionally, the new model was compared with MSW data from Kathiravale et al. [42].

Table 8. Comparison between experimental and predicted results based on physical components. Comparison between experimental and predicted results based on physical components from Malaysia [43].

Lab Results (MJ/kg) [43]	New Model (MJ/kg)	Variation %	Equation (1) (MJ/kg)	Equation (2) (MJ/kg)	Equation (3) (MJ/kg)
17	21.2	24.7	19	12.5	13

presents the results from three different physical mathematical models compared to both lab results and the new model.

The new model demonstrated better agreement with the lab results compared to Equations (2) and (3). Additionally, it was tested against ultimate analysis results from MSW in Nigeria [46], where the physical components yielded an HHV of 19.6 MJ/kg. In contrast, the new model predicted an HHV of 20.8 MJ/kg.

The prediction of HHV using the new model can be further refined by adjusting the energy content of all physical components of the MSW. For example, the energy content of food can be derived from nutrition labels, which specify the energy in calories. While the energy released from the combustion of food may not precisely match the caloric content listed, it can be assumed for simplicity that the two are equivalent. Food consists of macronutrients—fat, carbohydrates, and protein—that provide energy to the human body. The energy values for these macronutrients are as follows:

• Fat = 37.6 MJ/kg;
• Carbohydrates: [Sugar = 8.4 MJ/kg; Regular Carbs = 16.7 MJ/kg; Fiber = 8.4 MJ/kg];
• Protein = 16.7 MJ/kg.

Carbohydrates, being the most commonly consumed macronutrient, have an average energy content of 11 MJ/kg. Applying this value for food energy in the new model can improve the prediction of the HHV, aligning the results more closely with the lab results. This adjustment was effective for the results shown in both Table 7 and Table 8. With this refinement, the new model will exhibit a maximum variation of 6% compared to lab results in Table 7 and a variation of 12% compared to lab results in Table 8. Applying the new mathematical model to the contents of Kuwait MSW, the predicted energy by incineration can be calculated as shown in Figure 10.

Incineration, though sometimes associated with increased emissions, offers the significant advantage of being able to process various types of waste with minimal preparation, making it especially suitable for Kuwait, where the waste stream is diverse and there is an urgent need to reduce reliance on landfills. A study by Ibikunle et al. [47] reported an energy recovery rate of approximately 18–20 MJ/kg for incineration, closely aligning with the 18–19 MJ/kg predicted by our mathematical model. By applying this new mathematical model to Kuwait’s MSW data, using a food energy value of 11 MJ/kg, the HHV for the MSW was nearly 19 MJ/kg, with the lowest predicted energy from the model being 18 MJ/kg. This calculation, derived from Equation (4), demonstrates that Kuwait’s MSW can effectively be used to generate electricity. As illustrated in Figure 10, the electricity generated from MSW could supply over 10,000 houses, given that each house in Kuwait typically requires up to 70 kW. The mathematical model indicates significant energy recovery potential from implementing incineration technology in Kuwait, but it is crucial to evaluate the environmental impacts carefully. Incineration inherently releases various dangerous pollutants, including dioxins, NO_x, and CO₂, which can adversely affect public health and air quality if not properly managed. To ensure emissions remain well below international limits, any proposed incineration facility must incorporate advanced air pollution control technologies, such as scrubbers, filters, and electrostatic precipitators. These technologies have proven effective in significantly reducing harmful pollutants, thereby mitigating the overall environmental impact of the incineration process [48,49,50].

Research from countries like Denmark and Japan demonstrates that incinerators equipped with advanced emission control systems can reliably produce energy with minimal environmental impact and significantly reduce waste volumes [49,51,52]. For instance, Japan’s stringent air quality regulations have driven the development of highly effective emission control devices that capture harmful gases and reduce particulate matter emissions. Similarly, Denmark’s extensive experience with waste-to-energy incineration has proven that, with appropriate technologies, incineration can be a vital component of environmentally friendly waste management, contributing to environmental preservation and energy security [40]. These examples underscore the importance of Kuwait adopting a comprehensive approach that includes best practices in emission management to ensure that the benefits of waste-to-energy technologies are realized, while safeguarding environmental and public health.

11. Conclusions

This study underscores the critical role of effective waste management in mitigating the environmental, social, and health impacts associated with the increasing volume of MSW in Kuwait. WtE incineration emerges as a promising solution to reduce landfill reliance, while generating electricity from waste. The research demonstrates that WtE solutions, particularly incineration, not only address short-term waste management challenges but also promote a circular economy, fostering long-term sustainability. By transforming waste into energy, valuable resources are repurposed, leading to a substantial reduction in overall environmental impact. The findings highlight that incineration, when implemented with advanced emission control methods, can significantly decrease greenhouse gas emissions, including methane. This aligns with international sustainability goals and addresses Kuwait’s unique environmental challenges. This study also emphasizes the economic benefits of WtE systems, showing that reducing reliance on landfills can result in substantial cost savings, while meeting Kuwait’s growing energy needs. Incineration is particularly well suited to address the increasing demand for landfill space, making it both economically and environmentally efficient. The proposed waste management plan is designed to be scalable and adaptive, considering the specific waste composition and environmental conditions of Kuwait, and offers a comprehensive blueprint for other Gulf countries facing similar challenges. Utilizing a novel mathematical model, the study estimates that Kuwait’s waste has an HHV of approximately 19 MJ/kg, demonstrating significant energy potential, with the model’s accuracy validated against experimental data. The research suggests that converting waste into energy can meet a portion of Kuwait’s energy needs, while reducing landfill demand. Key recommendations are provided for policymakers, urging the integration of WtE solutions into national energy and environmental policies, essential for shaping Kuwait’s future waste management infrastructure and aligning it with Vision 2040, to meet both environmental and economic objectives.