An investigation of the status quo and prospects of concrete recycling practices in Hong Kong

Abstract

In Hong Kong, construction waste management has been a critical issue during the past two decades, as construction and demolition waste has contributed to significant portion of waste generated each year. As such, a series of initiatives have been implemented concerning pressing urgency to relieve burden of landfill spaces, including recycling of different materials. Provided that concrete takes up the most significant amount amongst the total construction waste in the local economy, it is believed that effective concrete recycling practices can improve the construction waste management, so the status quo and prospects of concrete recycling practices are focused. In this dissertation, background information of the existing construction waste management policies related to waste recycling will be reviewed, including the Construction Waste Disposal Charging Scheme which strongly impact the concrete recycling practices. The performance of these government efforts, statistics about waste recovery rate and operation routine of the concrete recycling practices will be reviewed for better understanding of the background. As construction waste management is directly impacted by a variety of factors that are associated with the stakeholders, i.e. government, recyclers, developers and contractors, their roles and responsibilities in waste management and recycling will also be investigated. Through the adoption mixed-method approach and stakeholder frameworks, the status quo of concrete recycling practices will be analysed by studying the concrete waste disposal rate, identifying their strengths and the promoting features of concurrent concrete recyclables created, which are Grade 200 Rock Fill, Eco-block and crushed concrete. It is found that the concrete waste disposal rate is quite satisfactory and remains at 0.6% to 0.7%. While the government incentives have motivated the waste recycling of recycler, along with a certain portion of developers and contractors being encouraged to engage in the practices. On top of that, numerous advantages of concrete recyclables also serve as the driving forces, e.g. affordability and wide scope of adoption. Notwithstanding the low rate of concrete disposal and strengths of the current practices, numerous shortcomings and hurdles are found that impeded the concrete recycling practices. With the high association with the stakeholders, the government tends to have a prevalence of bureaucracy and lacking of new initiatives, recyclers encounter different operation constraints and financial hurdles, as well as the challenges faced by developers and contractors which discourage them to supply construction waste for recycling in public fill bank. Limitations of concrete recyclables, like low legitimacy of quality standard and public misperception, also hinder their adoption and reuse. With regards to the problems identified, recommendations are proposed for the stakeholders to take action in improving the current concrete recycling practices. Amongst them, government is suggested to do the most, including regular review on current recycling initiatives, promoting recycling industry proactively and offering various subsidies or incentives for different construction practitioners, especially companies of relatively small scale. Only when the authority takes the lead will the other stakeholders follow the practices. Indeed, these measures are just the starting treads of the construction waste management, the success in exercising concrete waste recycling requires the continuing participation of every stakeholder, including the general public. With the persisting effort and cooperation of the parties, it is believed that the concept of sustainable recycling practices can be realised in near future.