Hong Kong is confronted by increasing problems of solid waste disposal, as it is an overpopulated city with limited land resources. Currently, solid waste disposal mainly relies on three landfills located in the New Territories. However, the current waste treatment facilities and policies cannot appropriately control and manage increments of solid waste. The primary reason is the increased amount of municipal solid waste caused by the growth of the population and the economy, with food waste accounting for the largest proportion of municipal solid waste in Hong Kong. The secondary reason is that the capacity of existing landfills will be exhausted in the near future as the level of waste generated continues to grow. To deal with these problems, in this paper, we propose five approaches with the aim of identifying the most sustainable strategy for efficient solid waste disposal in Hong Kong: a food waste recycling program; an municipal solid waste charging scheme; the implementation of incineration plants (i.e., waste to energy); black soldier fly bioconversion and a waste trading scheme; and black soldier fly bioconversion and a hybrid anaerobic digestion system. This is followed by a detailed demonstration of each approach, particularly focusing on the benefits, limitations, and implementation of each in the case of Hong Kong. The results of this study may shed light on how to effectively and sustainably manage the increasing amount of solid waste in Hong Kong.

The management of solid waste is a critical challenge in urbanized societies, and in the case of Hong Kong, the issue is particularly pressing. With a dense population and consumption-driven economy, the city generates approximately 11,000 tons of municipal solid waste daily, most of which ends up in its three nearly saturated landfills. This reliance on landfilling is unsustainable, not only due to the limited availability of land but also the environmental consequences it entails. Methane emissions from decomposing organic waste exacerbate climate change, while leachate from landfills poses risks to groundwater systems. These issues highlight the urgent need for a shift in waste management strategies toward sustainability.

Hong Kong's recycling rate remains low, despite growing environmental awareness among residents. Structural deficiencies, such as insufficient waste sorting infrastructure and a lack of public trust in the recycling process, continue to hinder meaningful progress. Many recyclables still end up in landfills due to poor sorting systems and limited transparency surrounding the fate of collected materials. The absence of advanced technologies to separate waste further compounds the inefficiency of the current system, leaving valuable resources untapped.

To address these challenges, the Hong Kong government has implemented initiatives such as the "Community Recycling Network" and the forthcoming "Municipal Solid Waste Charging Scheme." The "Community Recycling Network" aims to increase public participation in recycling by establishing accessible recycling stations across the city and promoting environmental education. However, the program faces criticism for the inconvenient locations of some stations and public skepticism about the actual recycling of collected materials. The waste charging scheme, which requires residents to pay for waste disposal based on weight or volume, seeks to incentivize waste reduction and recycling. However, the success of this policy depends on public acceptance, fair pricing, and effective enforcement mechanisms. Without complementary measures such as improved recycling infrastructure and robust public education campaigns, these policies may fail to deliver the desired outcomes.

International examples provide valuable lessons for Hong Kong. Australia, for instance, has adopted a comprehensive approach to waste management through its National Waste Policy, which aims for "80% average resource recovery rate" by 2030. The country has invested heavily in advanced recycling technologies, such as anaerobic digestion for organic waste and sophisticated systems for electronic waste recycling. China has demonstrated the effectiveness of strong regulatory enforcement and large-scale investment. It has implemented mandatory waste sorting in major cities and developed extensive waste-to-energy facilities to reduce landfill dependency. Japan exemplifies meticulous waste sorting systems and a culture of environmental responsibility, achieving high recycling rates through public education and transparent waste management practices. These examples highlight the importance of infrastructure development, technological innovation, and public engagement in building effective waste management systems.

Emerging technologies offer significant potential to address the challenges of solid waste sorting and resource recovery. Artificial intelligence and robotics are transforming waste segregation by automating processes, improving accuracy, and reducing labor costs. AI-powered optical sorters can identify and separate materials based on composition, color, and texture, while sensor-based systems using near-infrared spectroscopy can differentiate between various types of plastics with high precision. Robotic arms equipped with machine learning capabilities can further enhance sorting efficiency by identifying specific items and removing them from mixed waste streams. Chemical recycling technologies, which break down plastics into their basic components, offer a promising alternative to mechanical recycling by producing higher-quality recycled materials. These innovations not only improve recycling rates but also contribute to the development of a circular economy by closing the loop in resource utilization.

Hong Kong's waste management challenges are not unique but reflect broader global issues that require bold and innovative solutions. While policies like the "Community Recycling Network" and the waste charging scheme represent important steps forward, they must be supported by substantial investment in advanced technologies, enhanced infrastructure, and comprehensive public education programs to achieve meaningful change. Drawing from international best practices and embracing technological advancements, Hong Kong can transition from its current linear waste disposal model to a circular economy that prioritizes resource recovery and environmental sustainability. The success of these efforts depends on the collective commitment of government, businesses, and citizens to reimagine waste not as a burden but as a valuable resource. Through a holistic and collaborative approach, Hong Kong can address its waste management challenges and set a precedent for sustainable urban living.

By Dr. Bankee Kwan

Member of the National Committee of the Chinese People’s Political Consultative Conference (CPPCC) and the Permanent Honorary President and Past President of Federation of Hong Kong-Shanghai Associations

Dr. Philip Wong

Member of Royal Institution of Chartered Surveyors (MRICS)

Fellow of the Chartered Institution of Highways and Transportation (FCIHT)

The views do not necessarily reflect those of Orange News.

Photo: AFP