Fly-tipping is the illegal disposal of waste onto land and can range from a bin bag of household waste to copious quantities of domestic, commercial or construction waste. A decade after the Paris Agreement 2015 on climate change, there is increased urgency to implement inclusive policies that can contribute to sustainable waste management services and reduce the environmental impacts of fly-tipping. This study explores the characteristics of bulky waste kerbside collection services through analysis of website disclosures from local authorities across Scotland. A database was constructed to identify potential barriers to service uptake and provide insights for policy makers and waste managers. It is crucial to ensure that materials from this discrete waste stream do not leak out of the circular economy approach being pursued by the Scottish Government. The findings highlight underlying factors that may influence resident engagement with bulky uplift services and emphasise the importance of effective communication and inclusive policies for local authorities and waste managers. Our findings reveal critical gaps in accessibility, affordability, and operational design that may inhibit service uptake and contribute to fly-tipping. Recommendations include the adoption of inclusive booking and payment methods, progressive pricing policies, and coordinated digital solutions such as a unified smartphone app. These measures could support legitimate disposal behaviours, reduce environmental harm caused by fly-tipping, and strengthen Scotland's circular economy outcomes. Mitigating fly-tipping and improving bulky item disposal routes can reduce greenhouse gas emissions from landfill and support Scotland's climate targets by retaining products and materials in circulation.
In the present study, hydrothermal carbonization (HTC) of banana peel waste, showing a moisture content of 85 wt%, was carried out in a 500 mL stirred stainless steel autoclave at a temperature ranging between 180 and 250 °C, for a residence time of 0.5 h. The reaction solid residue was recovered via vacuum filtration and washed with distilled water before drying it in a ventilated oven at 105 °C, until constant weight, and stored in 50 mL plastic vials, before analytical characterization. Banana hydrochars were characterized in terms of proximate, elemental analysis, FTIR and high calorific value (HHV). Hydrochar mass yield showed a maximum at 220 °C (32 wt%), while gas and liquid mass yields increased monotonically with reaction temperature, up to 70 and 2 wt%, respectively. HHV increased with reaction temperature up to 27.13 MJ/kg, corresponding to an energy densification ratio EDR of about 169%. Mass yield and energy properties of banana hydrochar prove that a HTC treatment carried out at 250 °C for 0.5 h is able to produce a valuable solid biofuel showing the characteristics of lignite.
Aluminum, a critical mineral in modern industry and energy transition, presents substantial environmental and economic burdens when produced through primary methods due to its high energy consumption and associated emissions. Although secondary production through recycling offers significant energy and emissions savings, it is widely believed that a large volume of aluminum still ends up in Municipal Solid Waste Landfills, particularly in the form of used beverage cans (UBCs) and other post-consumer products. This paper explores the feasibility and challenges of recovering aluminum from landfills through landfill mining (LFM). It presents an in-depth review of the historical and current state of aluminum waste generation in the United States, highlighting the growing accumulation of aluminum in landfills and the limitations of existing recycling practices. The study evaluates the physiochemical conditions of landfills affecting aluminum stability and outlines key technologies for material recovery, including air classification, magnetic separation, eddy current separation, electrostatic separation, sink-float techniques, and optical sorting. Despite technological advances, the recovery of aluminum from landfills remains hindered by numerous barriers such as technical inefficiencies, contamination, oxidation, high operational costs, regulatory ambiguity, and public opposition. The findings emphasize the importance of pre-landfill aluminum recovery as a more viable and sustainable strategy. By diverting aluminum from disposal before landfilling, the environmental, economic, and logistical burdens of post-disposal recovery can be substantially mitigated. This review advocates for upstream integration of aluminum recovery into waste management systems as a pathway toward resource efficiency, landfill space conservation, and reduced reliance on energy-intensive primary production.
Recycling plastics is an energy intensive process, but entomoremediation (the use of insects to transform environmental contaminants), and insect-driven plastics degradation (plastivory) may offer a natural, low energy, cost effective approach to plastics waste reduction. Polystyrene and some polyethylene materials are amenable to degradation by darkling ground beetle (Tenebrionidae) adults and larvae, and a wide range of polyethylene can be degraded by waxworm moth larvae. Mandibular activity of the insects chewing on plastics serves to increase the surface area of the polymers that can be attacked by insect digestive enzymes and gut bacteria that can degrade the polymers into individual monomers and other low molecular weight compounds. The objective of this work was to determine the feasibility of an innovative solution to the plastics waste problem using a holistic, low technology, low cost, and low maintenance technique. Plastivory by ground beetle mealworm larvae was tested using small batch, mixed food and plastics waste compost bins. Different combinations of food waste and plastics were assessed and ultimately modeled through a continuum model of mealworm population dynamics. Our idealized, coarse-grained continuum population model suggests that a modestly-sized compost bin, can support a steady population of ~1100 mealworms that can degrade plastic at a rate of ~2 g of polystyrene foam per week. It is anticipated that this model will allow for assessing the extrapolation of empirically derived plastics degradation rates at various scales such as individuals and households, to industrial scales that would comply with municipal regulations.
Waste generators, particularly at the household level, waste collectors, and local governments play pivotal roles in municipal solid waste management (MSWM) systems worldwide, especially in developing countries. In the Indian state of Kerala, waste collection has been formalized through a predominantly female workforce known as the Haritha Karma Sena (HKS), which undertakes door-to-door collection of non-biodegradable waste from households. This initiative has significantly enhanced the efficiency of MSWM in the state. To systematically evaluate the performance of HKS and other key stakeholders in the MSWM system, this study proposes a comprehensive scoring system developed using the Delphi method. The framework encompasses twenty parameters across three primary stakeholders: waste generators, Haritha Karma Sena waste collectors, and Local Self Government Institutions (LSGIs). The scoring system is designed to identify critical performance gaps and guide improvements, ultimately enhancing the overall efficiency of MSWM in Kerala. Moreover, this model holds potential for adaptation in other developing countries with similar waste management challenges.
