Browsing by Author "Fisher, R."

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    Defining the defence industry using an ecological system and the application of ecological taxonomy
    (12th Defence and Security Economics Workshop, 2017-11-02) Fisher, R.
    This research examines the creation of the ecosystem where the defence industry is described using an ecological taxonomy and the development of the theory supporting classification of defence organisations within that taxonomy. Using recognised terminology, comparisons are made between defence organisations and organisms, associations and partnerships with populations and species, leading up to industry sectors and ecosystems and multiple sectors and biomes. The value of this approach is the ability to identify susceptibilities, resilience issues and the scope and interdependencies of defence. It enables those involved to reflect upon the organic natures of a complex system of systems. This work has already been applied to improving the visibility and transparency of the issues facing UK-based small-to-medium enterprises and the approach to exporting defence products.
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    Industrial wastewater treatment through bioaugmentation
    (Elsevier, 2018-06-28) Raper, Eleanor; Stephenson, Tom; Anderson, D. R.; Fisher, R.; Soares, Ana
    Bioaugmentation of activated sludge processes through the addition of microorganisms is employed with the aim of enhancing treatment, in particular the removal of priority pollutants. With industrial wastewaters, studies have covered target pollutants including ammonia and polycyclic aromatic hydrocarbons (PAHs): compounds that are regulated around the globe. However, bioaugmentation is a technique that has been associated with doubt in regard to its ability to benefit treatment processes. Failure of bioaugmentation has been reported to be associated with numerous factors that include the growth rate being lower than the rate of washout, insufficient inoculum size and substrate availability. Limitations of bioaugmentation can be overcome through techniques that include increased inocula dosing, pre-acclimatisation of inocula in side-stream reactors, addition of nutrients and surfactants and application of sufficient acclimatisation periods. Surveys of the literature show that a key area for further research should be towards acquiring a better understanding of the degradation pathways where bioaugmentation is applied. There also remains a need to undertake bioaugmentation efficacy studies at full scale with test and control streams. Further reporting on the economic viability of the technique is also necessary.
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    Nitrogen removal from coke making wastewater through a pre-denitrification activated sludge process
    (Elsevier, 2019-02-14) Raper, Eleanor; Fisher, R.; Anderson, D. R.; Stephenson, Tom; Soares, Ana
    Under the Industrial Emissions Directive (IED), coke production wastewater must be treated to produce an effluent characterised by a total nitrogen (TN) <50 mg/L. An anoxic-aerobic activated sludge pilot-plant (1 m3) fed with coke production wastewater was used to investigate the optimal operational requirements to achieve such an effluent. The loading rates applied to the pilot-plant varied between 0.198–0.418 kg COD/m3.day and 0.029–0.081 kg TN/m3.day, respectively. The ammonia (NH4+-N) removals were maintained at 96%, after alkalinity addition. Under all conditions, phenol and SCN− remained stable at 96% and 100%, respectively with both being utilised as carbon sources during denitrification. The obtained results showed that influent soluble chemical oxygen demand (sCOD) to TN ratio of should be maintained at >5.7 to produce an effluent TN <50 mg/L. Furthermore, nitrite accumulation was observed under all conditions indicating a disturbance to the denitrification pathway. Overall, the anoxic-aerobic activated sludge process was shown to be a robust and reliable technology to treat coke making wastewater and achieve the IED requirements. Nevertheless, the influent to the anoxic tank should be monitored to ensure a sCOD:TN ratio >5.7 or, alternately, the addition of an external carbon source should be considered.