Browsing by Author "Villa, Raffaella"
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Item Open Access Achieving drinking water compliance levels for metaldehyde with an acclimated sand bioreactor(Elsevier, 2020-07-06) Rolph, Catherine A.; Jefferson, Bruce; Brookes, Adam; Hassard, Francis; Villa, Raffaella;Metaldehyde removal was delivered to below the 0.1 µg L-1 regulatory concentration in a laboratory scale continuous upflow fluidised sand bioreactor that had undergone acclimation through selective enrichment for metaldehyde degradation. This is the first reported case of successful continuous flow biological treatment of metaldehyde from real drinking water sources treating environmentally realistic metaldehyde concentrations. The impact of the acclimation process was impermanent, with the duration of effective treatment directly related to the elevated concentration of metaldehyde used during the enrichment process. The efficacy of the approach was demonstrated in continuous flow columns at both laboratory and pilot scale enabling degradation rates of between 0.1 and 0.2 mg L-1 h-1. Future work needs to focus on optimisation of the sand bioreactor and the acclimation process to ensure viability and feasibility of the approach at full scaleItem Open Access Aeroterrestrial and freshwater microalgae biofilms: deposition and growth in aqueous and non-aqueous systems.(2016-12) Ledwoch, Katarzyna; Villa, Raffaella; Jefferson, BruceNon-suspended microalgal cultivation methods have gained an interest over the last decade. In contrast to traditional cultivation systems, where microalgae are grown in highly diluted suspensions, microalgae grow concentrated in biofilms over a particular substrate. Growth in biofilms gives higher biomass concentrations of end products and decreases overall water and energy consumption. However, there are research gaps in the field of biofilm formation and growth. The studies on material and strain properties and their effects on microbial attachment are very limited. So far, a small number of strains and materials have been tested, leading to many contradictory conclusions. In this thesis the primary colonisation of 36 material-strain pairings was tested and related to topographical and physicochemical properties of substrates. Experimental data was also confronted against properties of microalgal strains. Further microalgal biofilm development in aerial conditions, and its relation to substrate properties, was analysed for the first time. To address some of the sustainability issues associated with microalgal cultivation, a novel Humid Biofilm-Based Reactor (HBBR) was also proposed. This novel method focused on growing microalgae in a humid atmosphere enriched with nutrients. The natural phenomenon of biofilm development in aerial humid conditions was a working principle of the system, resulting in higher biomass concentrations than in other non-suspended reactors proposed so far. Using mist instead of a liquid medium significantly minimised the water consumption. No presence of a liquid medium in the reactor enabled easier maintenance of the system and improved light distribution. Growth trial in this novel reactor and its comparison to reference systems showed that HBBR was a promising way of culturing microalgae with higher growth rates, lower water and nutrient consumption, more effective light distribution and easier maintenance of the system.Item Open Access Aged-engineered nanoparticles effect on sludge anaerobic digestion performance and associated microbial communities(Elsevier, 2017-07-23) Eduok, Samuel; Ferguson, Robert M. W.; Jefferson, Bruce; Villa, Raffaella; Coulon, FredericTo investigate the potential effect of aged engineered nanoparticles (a-ENPs) on sludge digestion performance, 150 L pilot anaerobic digesters (AD) were fed with a blend of primary and waste activated sludge spiked either with a mixture of silver oxide, titanium dioxide and zinc oxide or a mixture of their equivalent bulk metal salts to achieve a target concentration of 250, 2000, and 2800 mg kg− 1 dry weight, respectively. Volatile fatty acids (VFA) were 1.2 times higher in the spiked digesters and significantly different (p = 0.05) from the control conditions. Specifically, isovaleric acid concentration was 2 times lower in the control digester compared to the spiked digesters, whereas hydrogen sulfide was 2 times lower in the ENPs spiked digester indicating inhibitory effect on sulfate reducing microorganisms. Based on the ether-linked isoprenoids concentration, the total abundance of methanogens was 1.4 times lower in the ENPs spiked digester than in the control and metal salt spiked digesters. Pyrosequencing indicated 80% decrease in abundance and diversity of methanogens in ENPs spiked digester compared to the control digester. Methanosarcina acetivorans and Methanosarcina barkeri were identified as nano-tolerant as their relative abundance increased by a factor of 6 and 11, respectively, compared to the other digesters. The results further provide compelling evidence on the resilience of Fusobacteria, Actinobacteria and the Trojan horse-like effect of ENPs which offered a competitive advantage to some organisms while reducing microbial abundance and diversity.Item Open Access Agricultural challenges today and in the future: the beneficial role of agroecology(Cranfield University, 2009-09) Keay, Gordon; Villa, RaffaellaInterest in agroecology is growing as evidence mounts that conventional agricultural methods are unsustainable, degrading the resource base (e.g. soil, water, crop diversity, biodiversity etc.) on which they depend. Alternative ways to produce foods that build soil fertility, protect ecosystems, conserve biodiversity and reduce energy inputs, provide the possibility of long-term productivity and ecological sustainability. The International Assessment of Agricultural Science and Technology for Development (IAASTD) have supported agroecology as a key set of solutions for world agriculture, which synergistically tackle development, sustainability and conservation goals. This study presents indicators to measure the sustainability of an agricultural practice which, placed in a hierarchical pyramid, demonstrates their importance and interconnected relationships. A comparative evaluation of agroecological and conventional systems is shown to assess the effects of management practices on the indicators. Agroecological approaches differ from conventional ones as they aim to sustain the soil and ecosystems by reducing synthetic inputs and creating alternative natural processes to maintain soil fertility and manage pests. Soil fertility is the essential indicator of sustainable agriculture, it was shown to improve in agroecological systems, indicated through increased soil microbial biomass (60% higher than in conventional agriculture) and earthworm abundance (up to 88% higher than in conventional agriculture). The loss of biodiversity due to current intensive farming practices is an indicator of unsustainability. In the agroecological systems biodiversity was shown to be comparatively higher. The diversity of bird and beetle species were recorded to be 50% and 38% more abundant respectively, and bat activity was shown to be 60% higher. These are bio-indicators of sustainable agriculture. The reduced chemical inputs led to an average of 50% less energy used on the agroecological systems. The resulting effects on yields showed great variation. One long term trial showed a 20% yield reduction in the agroecological system. Yet in times of drought, when advanced cropping systems were implemented, in developing countries yields were shown to be comparable, often significantly higher. This study provides solid evidence that the world’s future food security lies in the hands of sustainable agricultural practices. Agroecology demonstrates techniques that can be used towards reaching this vital goal.Item Open Access Algae reactors for wastewater treatment(Cranfield University, 2016-02) Whitton, Rachel Louise; Jefferson, Bruce; Villa, RaffaellaThe onset of the Water Framework Directive (WFD) will challenge water utilities to further reduce their wastewater phosphorus discharges to < 0.5 mg.L- 1 . Whilst conventional treatments, such as chemical dosing, are able to meet these new discharge consents, the strategies are representative of a linear economy model where resources are unrecovered and disposed. An alternative solution which can contribute to the aspiration of a circular economy is microalgae. Microalgae are ubiquitous in wastewater environments and assimilate phosphorus during their growth, to residual concentrations complementary of the WFD. Furthermore, microalgal biomass can be anaerobically digested to produce biomethane offering the potential for an energy neutral approach. However, uptake of microalgal systems are lacking in the UK through limited knowledge of operation; and the belief that such solutions are synonymous to large, shallow open ponds with extensive treatment times. The development of alternative microalgal reactors are increasingly investigated to overcome these implementation challenges. Of these, immobilised microalgae has shown great potential; and whilst within its infancy demonstrates the greatest opportunity for development and optimisation. This thesis determines the critical operational parameters that influence the remediation efficacy of immobilised microalgae for tertiary nutrient removal; including species selection, biomass concentration, treatment period and lighting; with recommendations for optimal performance. These recommendations are then applied to the design and operation of an immobilised bioreactor (IBR) to understand the key design and operating components that influence the overall economic viability. In doing so, the potential for an IBR to be economically viable, within the next decade, in comparison to traditional approaches are discussed.Item Open Access Assessing the potential of enhanced primary clarification to manage fats, oils and grease (FOG) at wastewater treatment works(Elsevier, 2020-04-20) Collin, Thomas Denis; Cunningham, Rachel; Asghar, Mohammed Qasim; Villa, Raffaella; MacAdam, Jitka; Jefferson, BruceDaily, sewage treatment works (STWs) receive large volumes of fats, oils and greases (FOG), by-products of food preparation. To increase FOG removal at STW, conventional primary sedimentation tanks (PSTs) can be enhanced using chemical coagulant or through dissolved air flotation (DAF) techniques. This work aimed to assess the potential benefits of enhanced primary treatment for FOG removal through an energy and costs analysis. To achieve this, a five-year sampling programme was conducted monthly at 15 STWs measuring FOG concentrations in crude and settled sewage (i.e. after primary treatment). In addition, two DAF pilot systems were trialled for four months and their performance, in terms of FOG removal, was assessed and compared to that of a control primary clarifier. Across the 15 STWs, influent FOG concentrations were found at 57 ± 11 mg.L−1. Chemical coagulants dosed prior to PSTs increased FOG removal rates on average to 71% whilst traditional sedimentation only achieved 50% removal. Effluent FOG concentrations were found between 12–22 mg.L−1 and 19–36 mg.L−1 respectively. By contrast, DAF achieved FOG effluent concentrations on average at 10 ± 4 mg.L−1 corresponding to 74% removal from a relatively low influent concentration of 40 ± 30 mg.L−1. Thus, enhanced primary treatments have the potential to reduce organic load to secondary treatment and increase energy generation through anaerobic digestion. The overall net energy balance was estimated at 2269 MWh.year−1 for the DAF compared to 3445 MWh.year−1 for the chemically-enhanced PST making it a less financially attractive alternative. Yet, in the case where the works require upgrading to accommodate flow or load increases, DAF appeared as a sensible option over sedimentation offering significantly lower capital costs and footprint. In relation to FOG management, upgrading all STWs is not realistic and will require understanding where the benefits would be the highest.Item Open Access An assessment of different extraction and quantification methods of penta- and hexa-chlorobenzene from SRF fly-ash(Elsevier, 2017-01-26) Balampanis, Dimitris E.; Coulon, Frederic; Simms, Nigel; Longhurst, Philip J.; Pollard, Simon J. T.; Fenech, Cecilia; Villa, RaffaellaHighly chlorinated benzenes, produced in the presence of organic matter and chlorine, are considered PCDD/Fs precursors, and are used as cost and time convenient substitute indicators for the indirect measurement of the latter. In this study penta- and hexa-chlorobenzene are quantified for the determination of the organochloride load of fly ash from solid recovered fuel incineration. Some of the chlorobenzenes are formed under ‘de novo’ conditions, through heterogeneous (ash particles/flue gases) reactions and are therefore deeply incorporated within fly ash. Accelerated solvent extraction (ASE) and ultrasonic solvent extraction (USE), along with the equivalent clean-up methods suggested by literature were compared to traditional Soxhlet. The extraction efficiencies achieved were 83 ± 7.5% for Soxhlet, 111 ± 19% for PFE, and 67 ± 17% for ultrasonication. Soxhlet extraction and clean-up through a multilayer silica gel column gave more precise results compared to the other sample preparation methods. Furthermore, performance comparison of gas chromatography fitted with either a mass spectrometer operated in single ion monitoring mode (GC-MS-SIM), or electron capture detector (GC- ECD) highlighted that ECD can be used for measuring chlorobenzenes traces down to 0.21 ng g−1, when the equivalent LOQ for MS-SIM was 3.26 ng g−1. The results further suggest that ECD can provide better peak integration than MS-SIM in the detection of chlorobenzenes in fly ash extracts, due to the detector's sensitivity to halogenated compounds.Item Open Access Bioengineering options and strategies for the optimization of anaerobic digestion processes(Taylor & Francis, 2014-04-17) Ferguson, Robert M. W.; Villa, Raffaella; Coulon, FredericAnaerobic digestion (AD) is a complex biological process, and the microbial diversity and dynamics within the reactor needs to be understood and considered when process optimization is sought after. Microbial interactions such as competition, mutualism, antagonism and syntrophism affect the function and the survival of single species in the community; hence, they need to be understood for process improvement. Although the relationship between process performance and the microbial community structure is well established, changes in the community might occur without detectable changes in gas production and reactor performance. Recent molecular-based studies have highlighted the complexity of AD systems revealing the presence of several uncultivated species and the need for further research in this area. However, this information is still rarely used for process optimization. The integration of next generation sequencing technologies, such as 454-pyrosequencing, with other techniques, such as phospholipid-derived fatty acids analysis, can provide a holistic understanding of the microbial community. In addition, the in-depth phylogenetic resolution provided can aid environmental ecologists and engineers to better understand and optimize the AD process and consolidate the information collected to date.Item Open Access Biological FOG degradation: development of a standardised bioadditive protocol.(Cranfield University, 2018-11) Gurd, Caroline; Villa, Raffaella; Jefferson, BruceFSE, wastewater, Gerber, COD:N, bioaddition, bioremediation, Fat, oil and grease (FOG) rich effluents from commercial food service establishments (FSEs) have been identified as major contributors to sewer blockages. Under UK Legislation, all FSE kitchens should be fitted with an ‘effective mean of grease removal’. Currently, microbial bioadditives, one of the preferred FOG management options, do not have an industry-agreed testing methodology to prove their ‘effectiveness’. The primary goal of this research was to generate the scientific knowledge underpinning a testing protocol for FOG- degrading bioadditives. Environmental conditions prevalent in FSE wastewater streams were identified in a characterisation of effluents from three catering outlets on Cranfield University campus and used as a basis for design of synthetic culture media for testing bacterial degradation. To address interferences caused by high levels of surfactants in FSE wastewater, a novel FOG quantification method, based on the Gerber method used in the milk industry, was developed for the protocol. This method is efficient at recovering emulsified FOG, and also allows emulsified and free fractions to be quantified separately. Microbial utilisation of different wastewater components was evaluated in batch degradation trials using a model bacterium, Bacillus licheniformis NCIMB 9375, and different synthetic wastewater compositions. The source of readily available carbon showed great influence on FOG-degradation response. FOG uptake was also influenced strongly by the carbon to nitrogen ratio in the media composition, with removal rate constants decreasing by over an order of magnitude from 0.0285 to 0.0026 h-1 when initial COD:N increased from 33:1 to 147:1. A cost-benefit analysis of the currently available FOG management solutions suggest that bioadditives, as a standalone solution, are the best option in terms of total cost and space requirements, followed by bioadditives used with grease separators. Combining physical and biological treatments can enhance the individual performance of both technologies and allow energy recovery from physically separated FOG.Item Open Access Carbon capture and biogas enhancement by carbon dioxide enrichment of anaerobic digesters treating sewage sludge or food waste(Elsevier Science B.V., Amsterdam., 2014-05-01T00:00:00Z) Bajón Fernández, Yadira; Soares, Ana; Villa, Raffaella; Vale, P.; Cartmell, EliseThe increasing concentration of carbon dioxide (CO2) in the atmosphere and the stringent greenhouse gases (GHG) reduction targets, require the development of CO2 sequestration technologies applicable for the waste and wastewater sector. This study addressed the reduction of CO2 emissions and enhancement of biogas production associated with CO2 enrichment of anaerobic digesters (ADs). The benefits of CO2 enrichment were examined by injecting CO2 at 0, 0.3, 0.6 and 0.9M fractions into batch ADs treating food waste or sewage sludge. Daily specific methane (CH4) production increased 11-16% for food waste and 96-138% for sewage sludge over the first 24h. Potential CO2 reductions of 8-34% for sewage sludge and 3-11% for food waste were estimated. The capacity of ADs to utilise additional CO2 was demonstrated, which could provide a potential solution for onsite sequestration of CO2 streams while enhancing renewable energy production.Item Open Access Characterisation and energy assessment of fats, oils and greases (FOG) waste at catchment level(Cranfield University, 2019-07-15 16:18) Collin, Thomas; Cunningham, Rachel; Jefferson, Bruce; Villa, RaffaellaData collected from literature and experimental work for the characterisation of several fats, oils and greases (FOG) wastes. This repository also contains data used for the energy assessment of FOG.Item Open Access Characterisation and energy assessment of fats, oils and greases (FOG) waste at catchment level(Elsevier, 2020-01-13) Collin, Thomas; Cunningham, Rachel; Jefferson, Bruce; Villa, RaffaellaSeveral of the waste materials that have a negative impact on the sewer system are produced by fats, oils and greases (FOG) discharged from commercial and domestic kitchens. These materials accumulate at different points in the sewer catchment, from kitchens to pumping stations, sewers and sewage treatment works (STWs), and comprise oily wastewater, floating agglomerates and hard deposits. Despite their detrimental effects, these waste materials have a high calorific content and are an ideal feedstock for energy recovery processes. So far, the overall volume of each type of waste and their physical-chemical properties in relation to their collection point are unknown. However, from a management point of view, knowledge on each feedstock quality and volumes is necessary to develop an economic viable solution for their collection and for energy recovery purposes. In this study, FOG wastes collected from households, food service establishments (FSEs), sewage pumping stations, sewers and STWs, were compared to sewage sludge in terms of organic contents and energy potentials. As expected, FOG recovered at source (households and FSEs) were ‘cleaner’ and had a higher energy content. Once mixed with wastewater the materials changed in composition and lost some of their energy per unit mass. Our results showed that around 94,730 tonnes.year−1 of these materials could be recovered from the Thames Water Utilities’ catchment, one of the most populated in the UK. These materials could produce up to 222 GWh.year−1 as biogas, close to double of what is produced with sewage sludge digestion and around 19% of the company energy needs. Finally, even with over six million households in the catchment, the results showed that most of the FOG waste was produced by FSEs (over 48,000 premises) with an estimated average of 79,810 tonnes.year−1 compared to 14,920 tonnes.year−1 from private households. This is an important outcome as recovery from FSEs will be cheaper and easier if the company decides to implement a collection system for energy recovery.Item Open Access Characterisation of food service establishment wastewater and its implication for treatment(Elsevier, 2019-10-08) Gurd, Caroline; Jefferson, Bruce; Villa, RaffaellaEssential for the selection of a reliable treatment system is the characterisation of the effluent to treat. Kitchen wastewater (KWW) from food service establishments (FSEs) is a strong organic and fat-rich effluent whose characterisation has not been sufficiently addressed. KWW composition is highly variable and linked to the FSE's size, the type of meals prepared and the amount of water used during the cleaning. COD, TSS and fat content (FOG) are the most common parameters found in literature. However, other physical and chemical parameters (e.g. temperature, pH, oil droplets characteristics and trace elements), correlated to commercial kitchen cleaning practices rather than the specific effluent, but equally influential on the treatment efficiencies of both physical and biological methods, have hardly been investigated. A comprehensive characterisation of wastewaters from three food service establishments was used to generate data to support the selection of appropriate FOG mitigation methods. Two novel analytical methods were used to quantify the proportion of emulsified FOG and associated droplet size from different kitchen washing effluents. The results showed that more than 90% of the FOG from the dishwasher effluent and around 35% of sink one was emulsified, with droplet sizes less than 100 μm, well below the removal capabilities of conventional grease interceptors, but easily removed using biological means. From the WW composition results, a formula for predictive modelling was derived to represent average organic matter composition for kitchen wastewater as C20H38O10N, applicable in remediation processes. These results offer a good starting point for the design, operation, and optimisation of wastewater treatment systems of oil-rich KWW.Item Open Access Characterisation of food service establishment wastewater and its implication for treatment(Cranfield University, 2019-10-18 09:59) Villa, Raffaella; Jefferson, Bruce; Gurd, CarolineEssential for the selection of a reliable treatment system is the characterisation of the effluent to treat. Kitchen wastewater (KWW) from food service establishment (FSE) is a strong organic and fat-rich effluent whose characterisation has not been sufficiently addressed. A comprehensive characterisation of wastewaters from three food service establishments was undertaken to generate data to evaluate appropriate FOG management strategies.Item Open Access Comparative study on the combustion and gasification of solid recovered fuels. Emphasis on residues characterisation and chlorine partitioning(Cranfield University, 2009-10) Balampanis, Dimitris E.; Villa, RaffaellaThermal treatment is recognised as a valid option within the waste management hierarchy for the recovery of the energy content of waste. Recent developments in the field are signposted from emergent technologies and the standardisation of solid recovered fuels. This work comparatively examines the fluidized bed combustion and gasification of a novel material; East London’s solid recovered fuel. Emphasis is given on the characterisation of the solid residues produced from the two thermal treatment techniques and chlorine partitioning, in particular. Chlorine mass balances are studied under steady state conditions for combustion and gasification. Furthermore, trace metals content, chlorobenzenes, major elements, crystalline structures, and leaching behaviours are compared in the two residues types. For the characterisation of these residues a series of analytical methods have been applied and compared for their efficiencies. Results indicate that gasification produces 5-6 times less HCI than combustion. Furthermore, gasification residues retain higher amounts of CI and in less water soluble forms. However, gasification residues have 3-8 times higher organochlorides load, expressed chlorobenzenes. This work generates novel data on the comparative characterisation of waste thermal treatment residues. These data contribute towards the technical confidence for further utilisation of solid recovered fuels, and the knowledge over the residues’ properties.Item Open Access Compositional analysis of excavated landfill samples and the determination of residual biogas potential of the organic fraction(Elsevier, 2016-06-08) Garcia, J.; Davies, S.; Villa, Raffaella; Gomes, D. M.; Coulon, Frederic; Wagland, Stuart ThomasThe objectives of this study were to assess the biogas potential of landfilled materials and to further validate the suitability of the enzymatic hydrolysis test EHT as a valuable alternative to substitute the standardised test currently in use (BMP). Both tests were applied to a range of landfill waste samples. The waste composition and volatile solids content (VS) profile together with the BMP test results showed that the biogas potential of the waste samples was directly related to their VS content, as expected. The positive correlation between the VS and the BMP test (r = 0.67) suggests that the first could be used as a primary indicator of biogas potential of waste samples. Nevertheless, it should be validated against the BMP test because, occasionally, the VS content does not equate to the biogas production. This was mainly due to the paper content of the samples which also correlates positively (r = 0.77) with the BMP biogas production. The EHT results showed a higher correlation with the BMP test (r = 0.91) than in previous studies which used a wider mixture of enzymes containing cellulase, hemicellulase and carbohydrase. This finding positions the EHT as a quick assessing method for the biodegradability of waste samples in future sample regimes.Item Open Access Compositional and physicochemical changes in waste materials and biogas production across 7 landfill sites in UK(Elsevier, 2016-08-28) Frank, R. R.; Cipullo, Sabrina; Garcia, J.; Davies, S.; Wagland, Stuart Thomas; Villa, Raffaella; Trois, C.; Coulon, FredericThe aim of this study was to evaluate the spatial distribution of the paper and fines across seven landfill sites (LFS) and assess the relationship between waste physicochemical properties and biogas production. Physicochemical analysis of the waste samples demonstrated that there were no clear trends in the spatial distribution of total solids (TS), moisture content (MC) and waste organic strength (VS) across all LFS. There was however noticeable difference between samples from the same landfill site. The effect of landfill age on waste physicochemical properties showed no clear relationship, thus, providing evidence that waste remains dormant and non-degraded for long periods of time. Landfill age was however directly correlated with the biochemical methane potential (BMP) of waste; with the highest BMP obtained from the most recent LFS. BMP was also correlated with depth as the average methane production decreased linearly with increasing depth. There was also a high degree of correlation between the Enzymatic Hydrolysis Test (EHT) and BMP test results, which motivates its potential use as an alternative to the BMP test method. Further to this, there were also positive correlations between MC and VS, VS and biogas volume and biogas volume and CH4 content. Outcomes of this work can be used to inform waste degradation and methane enhancement strategies for improving recovery of methane from landfills.Item Open Access Data for the paper "From full-scale biofilters to bioreactors: engineering biological metaldehyde removal"(Cranfield University, 2019-07-17 11:45) Hassard, Francis; Jefferson, Bruce; Villa, Raffaella; Brookes, Adam; Choya, Andoni; Iceton, Gregg; Rolph, CatherineDatasets for Rolph, C.A., Villa, R., Jefferson, B., Brookes, A., Choya, A., Iceton, G. and Hassard, F., 2019. From full-scale biofilters to bioreactors: engineering biological metaldehyde removal. Science of the Total Environment, 685, pp.410-41.Item Open Access Data for the paper "Influence of light regime on the performance of an immobilised microalgae reactor for wastewater nutrient removal"(Cranfield University, 2019-10-31 18:14) Whitton, Rachel; Ometto, Francesco; Villa, Raffaella; Pidou, Marc; Jefferson, BruceWastewater nutrient remediation data using immobilised microalgae under differing light regimes including wavelength (nm), duty cycles and photoperiods (on:off cycles), light transmittance and attenuation depths.Item Open Access Deposition onto heat exchanger surfaces from the co-firing of coal and biomass(Cranfield University, 2011-12) Legrave, Nigel A; Simms, Nigel J.; Kilgallon, Paul; Villa, RaffaellaIn the latter part of the 20th century, there has been a continuing global concern of the consumption of fossil fuels used in power production. There is further concern of the gaseous emissions that are created from this consumption and an awareness of climbing carbon dioxide (CO2) levels that are exhausted into the atmosphere. The concept of co-firing fossil fuel with varying levels of biomass species is not new but there is a requirement to explore its applications further in the interests of both the environment and power production. With dwindling fossil fuel resources, co-firing with biomass is a logical step forward as biomass is a generally a renewable product – whereas fossil fuels are not. More importantly, the study of effects of burning higher biomass percentages on the heat exchanger matrix of power plants requires more attention. This has been explored before in other studies that have resulted in inefficiencies within the power generation plant. The main of objectives of this research were to: co-fire coal with biomass over a wide range of mixes within a combustion environment; monitor the gaseous emissions and capture and analyse the deposits that are formed on deposit capture probes. The analysis of data obtained will enabled further research to be carried out and model deposit flux behaviour of simulated heat exchanger models and materials in the future.