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This research work investigates the potential applicability of waste paper in the production of ceiling boards with focus on achieving: environmental sustainability, safe disposal of waste paper and more cost effective production of materials. The main view was to provide an alternative to the conventional asbestos ceiling boards that are costly and also pose health risks. Three mix designs were formulated and used for the casting (1:1, 1:1.5 and 1:2), varying in regards of the weight of the waste paper components. CaCO3 was added to the mix as an additive as well as starch bond glue to aid binding. Laboratory experiments were conducted to determine the properties and suitability of the produced boards. Properties such as water absorption, abrasion, compressive strength, flexural strength and ultimate loads were considered for comparison. The boards with 1:1 mix ratio displayed the best results of the test properties hence, its mechanized manufacturing was recommended.

The environmental challenges such as high energy demand, large CO 2 emission, and exorbitant raw material consumption among others associated with ordinary Portland cement led researchers to the search for alternatives and thus the advent of geopolymer concrete. Fly ash, a waste product of the thermal generating power station, has been the base material commonly used in geopolymer production. However, Nigeria depends majorly on hydro-power and hence, fly ash is unavailable and this has contributed to the restricted application of geopolymer technology. Therefore, the suitability of brewery sludge residue (a waste byproduct generated in high quantity from brewing process) as an alternative base material in geopolymer concrete was investigated in this study. The physical and chemical properties of brewery sludge residue ash (BSA) were investigated to assess its suitability for use as a base material for geopolymer binder. Brewery sludge residue ash-based geopolymer concrete (BSAGC) specimens were produced by activating BSA with selected alkaline liquids (NaOH and Na 2 SiO 2) used as activator. The BSAGC specimens were subjected to compressive strength to assess the strength development and consequently the effectiveness of the polymerization reaction that occurred. It was found that, amongst other factors, the BSA exhibits less satisfactory oxide characteristics at 425micron particle size utilised and consequently the compressive strength development was low at 28days curing duration at the 1:2:4 mix proportioning threshold adopted for the BSAGC mix. Given the marginal strength development of BSAGC, BSA could be reckon as having potentials for application as base material for geopolymer binder, however, more investigation is required to determine the optimum processing parameters for its usage as a base material for geopolymer binder and geopolymer concrete.

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The complexity of processes and constraints associated with redevelopment of brownfield lands calls for provision of relevant, adequate, sufficient, up-to-date, and easily accessible information on brownfield lands to enable developers make an informed decision when navigating the hurdles of brownfield redevelopment. Furthermore, the various obstacles and barriers that developers encounter during decision making for brownfield redevelopment has continued to contribute to the limited uptake of brownfield lands in England by developers for redevelopment and regeneration. This study was conducted to explore the factors that developers consider when redeveloping brownfield lands and to present a decision criterion that will support brownfield site selection and subsequent regeneration. A mixed methodology using qualitative and quantitative approaches was adopted to investigate the factors, criteria, and information that developers consider when making decisions for brownfield redevelopment. Data collection was carried out using a literature review and interviews with brownfield experts. Using a purposeful sampling approach, a total of 11 brownfield stakeholders, which cut across key experts involved in brownfield redevelopment within the Black Country region of England, was interviewed. Each expert interviewed holds a stakeholder critical role in regulatory organisations and construction industry organisations, including local authorities, geo-environmental organisations, land remediators and consultants, housing developers, etc. A comparative analysis of evidence obtained from developer interview responses, the literature review, and the brownfield register showed that 57% of factors, criteria, and information such as cost/capital expenses, funding, contamination level, infrastructure, water risk, neighbours, connectivity (digital, energy networks/grid), and access and transport, which developers require for decision making relating to redevelopment of brownfield sites, are not available on a standard local authority’s brownfield land register. To address the identified information gaps, this study developed “The BRIC Index”, a decision-making tool that incorporates a GIS-based system to facilitate screening of brownfield sites based on specified criteria and to help identify risks, contamination, and remediation costs of brownfield development. The effectiveness of the BRIC Index was validated through successful usage for site selection by various SMEs in the Black Country.