Extraction, use and disposal of construction materials in Great Britain and Thailand

Abstract

Construction growth has become a causal factor in economic competitiveness with rapid urbanisation. Consequently upstream businesses, such as cement and concrete manufacture, also expand. Sustainability balances economic, environmental and societal issues and although this philosophy is well developed in the European Union (EU), there seems to be less practical awareness amongst the ten countries in the Association of Southeast Asian Nations (ASEAN). This thesis investigates and compares the flow of key mineral-based components of national construction materials (cement, aggregates and concrete) from extraction to disposal in two case studies: Great Britain (EU) and Thailand (ASEAN), from the perspective of sustainable resource and waste management. The study considers material needs and wastes arising associated with future and expected demolition of residential accommodation, measured as national floor area including future concrete demand and concrete waste from national housing, as concrete is mostly used in the Thai residential sector. To compare the difference between the two national and continental strategies in more depth, it also identifies and evaluates policies and taxations influenced by EU regulation that enable Great Britain to achieve the highest rates of recycled aggregates (29%) and the 70% reuse and recycling rate of construction and demolition waste (C&D waste). Then, options for Thai policy integrally relating to construction materials and waste are developed using lessons learned from the EU and Great Britain. Material Flow Analysis (MFA) is used to combine results from both national cement and concrete industries, together with primary and recycled aggregates from the aggregate market made for annual concrete manufacturing in Great Britain, and primary aggregates only for Thailand. Government and manufacturing data for 2012 were used for calculating national cement production by chemical calcination. Then, all MFA outcomes (cement production, virgin and recyled aggregates including waste and emissions) of each nation are presented using Sankey diagrams. This research also considers national estimates of future and prospective demolition of floor area including future concrete demand and waste in the residential sector using Stock Dynamic Analysis (SDA) with Gross Domestic Product (GDP) to indicate demand. Great Britain with its 61.9 million and Thailand with 64.5 million inhabitants had quite similar populations in 2012. MFA results show that more than 30% of Thai cement and clinker were exported as cementitious products to ASEAN trading countries, in particular, which is double the annual amount of domestic cement used for concrete manufacturing in the whole of Great iii Britain. Moreover, the results also show that Thailand used six times more indigenous minerals for cement manufacturing and exporting than Great Britain. The 2012 Thai concrete stock is approximately 3.8 times (256.14 million tonnes: Mt) greater than Great Britain (67.73 Mt). For aggregates used for concrete production, Great Britain uses both primary (48.04 Mt) and recycled aggregates (5 Mt) while Thailand consumes only primary aggregates (214.66 Mt). The results of SDA show that Thailand uses a large amount of concrete for the housing sector presently due to a shorter lifetime of housing compared to Great Britain. Using 50 years of Thai housing lifespan to compare with Great Britain scenarios, concrete waste generation in Thailand will peak mostly around 2050. This period will produce a similar amount of concrete waste to a scenario of 100 years lifespan in Great Britain (2100). In addition to longer lifetime of housing, an increase in renovation activities and higher quality of housing construction like Great Britain can extend the time of demolition activities and can delay the problem of concrete waste that needs to be disposed of properly in Thailand. Thailand has no strategy for encouraging recycling of construction materials, with no registered data and no integrated sustainability policy. In the foreseeable future, Thailand may experience problems such as rapidly depleted resources and improper C&D waste management. In contrast, Great Britain has experience in managing C&D waste (particularly concrete waste) as well as conservative consumption of natural resources, involving environmental taxes with cement and associated natural resources used only within the country. Contractors are also encouraged to use recycled aggregates for construction activities, including producing new concrete following a standard from the British Standards Institute (BSI, BS EN 12620:2013 Aggregates for Concrete), with other supporting organisations such as the Mineral Products Association (MPA) and Waste Resource Action Programme (WRAP). However, with the above strategies, Great Britain still has not achieved the anticipated target of recycled aggregate use. Shortly, the ASEAN countries will form the ASEAN Economic Community (AEC) aiming to achieve a single market and production base. Therefore, there is an opportunity to report on cement and other material requirements and wastes in construction, including comparing awareness and performance of natural resources and waste management practices of two main trading regions. Capitalising on the experiences from the Great Britain case study to cope with rapid economic growth and societal change, this thesis gives some valuable insights into the use of appropriate tools for policy-makers that consider the construction industry and its raw materials including its waste management systems for Thai national policy but also other ASEAN countries.