Atiq Uz Zaman

Comparative study of municipal solid waste treatment technologies using life cycle assessment method

The aim of the study is to analyze three different waste treatment technologies by life cycle assessment tool. Sanitary Landfill, Incineration and gasification-pyrolysis of the waste treatment technologies are studied in SimaPro software based on input-output materials flow. SimaPro software has been applied for analyzing environmental burden by different impact categories. All technologies are favorable to abiotic and ozone layer depletion due to energy recovery from the waste treatment facilities. Sanitary landfill has the significantly lower environmental impact among other thermal treatment while gases are used for fuel with control emission environment. However, sanitary landfill has significant impact on photochemical oxidation, global warming and acidification. Among thermal technology, pyrolysis-gasification is comparatively more favorable to environment than incineration in global warming, acidification, eutrophication and eco-toxicity categories. Landfill with energy recovery facilities is environmentally favorable. However, due to large land requirement, difficult emission control system and long time span, restriction on land filling is applying more in the developed countries. Pyrolysis-gasification is more environmental friendly technology than incineration due to higher energy recovery efficiency. Life cycle assessment is an effective tool to analyze waste treatment technology based on environmental performances.

IDENTIFICATION OF WASTE MANAGEMENT DEVELOPMENT DRIVERS AND POTENTIAL EMERGING WASTE TREATMENT TECHNOLOGIES

Application and development of municipal solid waste treatment technology depends on various socio-economic and environmental factors. All those factors are work as development drivers for waste management systems. The study aims to identify key drivers from case studies of waste management development trend in Sweden. Social, economic and environmental drivers are identified and presented in this study. The study identifies personal behaviour, local waste management practice, consumption and generation of waste as the key social drivers. Resource value of waste, economic benefit from waste treatment facilities and landfill tax have been acknowledged as economic drivers for developing waste treatment technology. Moreover, global climate change, environmental movement and awareness have been working as environmental drivers for developing various waste treatment methods in Sweden. In addition, the study aims to analyse emerging waste treatment technologies based on a number of literature review and questionnaire survey. Dry composting, pyrolysis-gasification, plasma arc, and anaerobic digestion have been identified as potential emerging technologies for waste management systems in Sweden.

Life cycle assessment of pyrolysis-gasification as an emerging municipal solid waste treatment technology.

Waste-to-energy technologies are considered as one of the key waste treatment technologies due to their energy and heat recovery efficiencies from the waste. A number of research studies were accomplished to understand the potential environmental burdens from emerging waste treatment technologies such as pyrolysis–gasification (PG). The aim of this study was to examine the PG of municipal solid waste (MSW) treatment process through a life cycle assessment (LCA) method. The study also includes a comparative LCA model of PG and incineration to identify the potential environmental burdens from the existing (incineration) and emerging (PG) waste treatment technologies. This study focused on ten environmental impact categories under two different scenarios, namely: (a) LCA model of PG and (b) comparative LCA model of PG and incineration. The scenario (a) showed that PG had significant environmental burdens in the aquatic eco-toxicity and the global warming potential impact categories. The comparative scenario (b) of PG and incineration of MSW showed that PG had comparatively lower potential environmental burdens in acidification, eutrophication, and aquatic eco-toxicity. Both LCA models showed that the environmental burdens were mainly caused by the volume of the thermal gas (emissions) produced from these two technologies and the final residue to disposal. Therefore, the results indicate that the efficiency and environmental burdens of the emerging technologies are dependent on the emissions and the production of final residue to the landfill.

Household Waste Management in High-Rise Residential Building in Dhaka, Bangladesh: Users' Perspective

The Dhaka City Corporation (DCC) is primarily responsible for collecting and managing waste in Dhaka, Bangladesh. A significant amount of waste in Dhaka is not collected due to lack of infrastructure, funds and collection vehicles. Despites Dhaka’s limited waste management service, community based door-to-door waste collection from households to local waste bins is considered as a success. Informal waste recycling systems is also highly effective in waste recycling and job creations for the poor. Even though both horizontal and vertical expansion is prevalent in Dhaka, there has been an increasing trend in vertical expansion of the city in recent years as horizontal expansion is not possible due to barriers such as the built up urban core and low lying flood plains. Very limited number of studies has been conducted on waste management system in high-rise residential buildings in Dhaka. Therefore, this study focuses on the waste management scenario of high-rise residential buildings in Dhaka. The study is particularly interested in the socio-demographic, cultural and environmental features in high-rise residential buildings. The study identified key areas in waste management systems in high-rise residential buildings which is the avenue for future studies for integrating waste management strategies in high density residential development in Dhaka. Based on the findings, the study recommends a further examination of the integration of waste management infrastructure in the high-rise residential building development in Dhaka.

Development of demand forecasting tool for natural resources recouping from municipal solid waste

Sustainable waste management requires an integrated planning and design strategy for reliable forecasting of waste generation, collection, recycling, treatment and disposal for the successful development of future residential precincts. The success of the future development and management of waste relies to a high extent on the accuracy of the prediction and on a comprehensive understanding of the overall waste management systems. This study defies the traditional concepts of waste, in which waste was considered as the last phase of production and services, by putting forward the new concept of waste as an intermediate phase of production and services. The study aims to develop a demand forecasting tool called ‘zero waste index’ (ZWI) for measuring the natural resources recouped from municipal solid waste. The ZWI (ZWI demand forecasting tool) quantifies the amount of virgin materials recovered from solid waste and subsequently reduces extraction of natural resources. In addition, the tool estimates the potential amount of energy, water and emissions avoided or saved by the improved waste management system. The ZWI is tested in a case study of waste management systems in two developed cities: Adelaide (Australia) and Stockholm (Sweden). The ZWI of waste management systems in Adelaide and Stockholm is 0.33 and 0.17 respectively. The study also enumerates per capita energy savings of 2.9 GJ and 2.83 GJ, greenhouse gas emissions reductions of 0.39 tonnes (CO2e) and 0.33 tonnes (CO2e), as well as water savings of 2.8 kL and 0.92 kL in Adelaide and Stockholm respectively.

Framework for Low Carbon Precinct Design from a Zero Waste Approach

The consumption-driven society today produces an enormous amount of waste, which puts pressures on land, pollutes the environment and creates economic burden. ‘Zero waste’ concept, a whole system approach aiming to achieve no waste along the materials flow through society, hasbecome one of the most visionary concepts for tackling growing waste problems. System Dynamics (SD) approach is applied in the proposed framework for designing the waste management in a zero waste residential precinct. A cost-benefit analysis (CBA) is incorporated to supplement the SD framework to evaluate the total cost and benefit of waste and resources throughout the material flow chain. The authors proposed a list of parameters under the categories of process, technology and infrastructure, socio-economic and institutional, social- environment, to be tested in future case study of Bowden village, SA, Australia. The framework provides an inventory of leverage points that helps policy-makers design waste policies and allocate resources effectively, with minimum environmental impact and optimum social benefits. It also helps planning professionals and business stakeholders better understand the costs and benefits of different scenarios for achieving a zero waste residential precinct.

Enabling an effective knowledge and information flow between the phases of building construction and facilities management

Purpose The purpose of this study is to investigate ways of transferring knowledge and information during the life-cycle phases of construction projects, particularly between the construction and occupancy phases, and to find an approach to minimise knowledge and information gaps during the handover process. Design/methodology/approach The study applied a qualitative approach involving a literature review and an archival analysis of information flow in the studied cases of a construction project, followed by a cross-cases analysis and expert interviews. Data on information flow were collected from three cases of building construction projects in Perth, Western Australia. In addition, a total of 18 local facilities management experts were interviewed to identify the key reasons of knowledge and information gaps and to propose an effective knowledge flow model. Findings The findings of this study indicated a significant knowledge and information gap, which exists during the handover process in construction projects in Western Australia. The findings of case analysis and expert interviews identified that the project handover guidelines were often ignored in construction projects in Western Australia, and the handover phase was not given the same priority as the design and construction phases by most of the project stakeholders, which led to information and knowledge gaps between the project construction and post-occupancy phases. The study conducted, integrated knowledge and information flow modelling to analyse the knowledge and information gaps followed by mapping the gaps against existing knowledge sharing frameworks (KSFs) before proposing an integrated knowledge sharing conceptual model to improve current practice and to enhance the information flow during the various phases of the construction project life cycle. Research limitations/implications The study is based on three cases in Perth, Western Australia, and thus the findings and recommendations are contextual. Whilst laying a good foundation to do so, further research is needed to investigate more cases in Western Australia and beyond to fully generalise the findings from this study. Originality/value The study contributes to improve the handover process and information flows in project life-cycle phases in Western Australia and develop an information flow model followed by bringing together existing KSFs, namely, the open communication channel (OCC), soft landing framework (SLF) and building information modelling (BIM), to propose an integrated knowledge sharing conceptual model. The methodology used here to analyse the information flow in a diagrammatic manner, the mapping of FM issues against the KSFs’ capabilities and a conceptual model to facilitate change in the industry’s silo mindset are the main contributions of this paper.

Towards developing robust climate risk management strategies in the estuarine park of the Swan River, Western Australia

Purpose This study aims to support the development risk management strategies towards improving the resilience of assets located in the estuary and lower level of the Swan River, Western Australia. The study evaluated the key role of Federal/State policies in adaptation planning and the communication and interface between various stakeholders, including State/Local governments, construction professionals, property developers and landowners. Design/methodology/approach The study applied a mixed research approach through a questionnaire survey followed by an in-depth interview involving local construction experts. Collected data were analysed following the grounded theory methodology style of data analysis. Findings The findings revealed a convoluted understanding of communication networks and responsibility for owning the future risks between relevant stakeholders. As a result, a framework illustrating clear process and roles in mitigating risk and implementing adaptive asset management measures has been formulated and presented in this study. Originality/value Scientific evidence suggested that sea-level rise and increased frequency of major coastal flooding events are inevitable as early as 2100, and having a comprehensive risk management plan of assets to anticipate climate risks and to improve urban resilience is essential. The proposed framework is aimed at local stakeholders in improving current state of communication and adaptation planning as a pathway to develop a robust risk management strategy.

Unlocking the potential of early contractor involvement in reducing design risks in commercial building refurbishment projects – a Western Australian perspective

ABSTRACT The commercial refurbishment sector is widely gaining popularity, particularly in industries such as the Western Australian construction industry in order to effectively house commercial businesses and operations. Unfortunately, commercial refurbishments have long been characterised by its added complexity, risk and uncertainty facing the management and delivery of such projects. The uncertainties are largely attributed to the segregated relationship between design and construction processes. Among a multitude of options in procuring refurbishment projects, the early contractor involvement (ECI) emerged as a procurement route that bridges this typical gap between design and construction, promotes a collaborative design process and offers opportunity for risk mitigation and certainty of delivery. Whilst appearing as a worthy candidate to procure refurbishment of commercial buildings, anecdotal evidence have indicted the potential of ECI to reduce design risks through synergising the contractor’s construction expertise into the design process. In light of this, the paper aims to report the findings from a recent research project conducted in Western Australia on this topic through case study approach. The findings revealed the specific points and activities during design of commercial building refurbishment where the contributions of the contractor are optimum in reducing design risks. This is captured in the resultant process map specifically developed for this type of projects under the ECI scheme. The process map is expected to further support project teams at the early design stage of a commercial building refurbishment projects to devise a robust strategy to fully benefit from procuring their project through ECI.