In this master thesis work calcination parameters' impact on the resulting quicklimes slaking reactivity is investigated. This is done by calcination of three different sedimentary limestones in an N2 atmosphere according to a design of experiment matrix. The limestones are from Wolica Poland, Slite Sweden and Jutjärn Sweden. The temperatures and residence times are varied between 1000ºC, 1050ºC, and 1100ºC for 5 min, 27.5 min, and 60 min. There were seven experiments per limestone sample. The calcination experiments were conducted in an electrical muffle furnace.When the limestone samples were calcined, the resulting quicklimes slaking reactivity was tested according to standard SS-EN 459-2:2010 Building lime - Part 2: Test methods. Four different parameters were used to determine the slaking reactivity, these were the maximum temperature, how much the temperature increases under the initial 30 s, the time it takes for the temperature to reach 60ºC, and the time for the slaking to become 80% finished.From the slaking reactivity experiments, the calcination parameters to produce the most reactive quicklime for the limestone from Wolica and Jutjärn are 1000ºC for 60 min, and for the limestone from Slite 1100ºC for 5 min. For all three limestones the least reactive quicklime was received by calcining at 1100ºC for 60 min. The most and least reactive quicklimes were analyzed in SEM, where it could be seen that the least reactive quicklime samples were coarser compared to the most reactive samples. Depending on what slaking reactivity parameter is of interest, the calcination settings should be different and can be an indication for operation parameters for industrial kilns. The statistical analysis on the experimental model showed that the experiment had a poor statistical fit for most of the experiment. This could be due to that the model possibly was too simple to describe the calcination parameters complex impact on the slaking reactivity.

This thesis investigates the application of latent variable methods to three combustion processes. Multivariate analysis of flame images and process data is performed to predict important quality parameters and monitor flame stability. The motivation behind this work is to decrease operational costs and greenhouse gases in these energy intensive processes. The three combustion processes studied are a lime kiln, a basic oxygen furnace and a coal-fired boiler. In lime kiln operation, the main goal is to stabilize final product temperature in order to reduce fouling and energy costs. Due to long process dynamics, prediction of product temperature is required at least one hour in advance for potential use in a control scheme. Several methods for extracting features from flame images were investigated for the prediction of the temperature. The best method is then combined with process data in a PLS model that also incorporates dynamic information. The analysis revealed that prediction one hour into the future is successful using latent variable methods. In the basic oxygen furnace analysis, the main goal is to predict end-point carbon of the batch process. Termination of the batch as soon as the desired carbon is attained reduces oxygen consumption and thus operational cost. Traditional image analysis is used to identify a constant field of view in the flame images. Multivariate image feature extraction methods were then used in combination with process data to successfully predict the final carbon content of the heat. The coal-fired boiler analysis focuses on monitoring of flame stability at different production and air to fuel levels of the boiler. Prediction of energy efficiency and off-gas chemistry from flame images is also investigated. An unexpected result was the ability to use the installed cameras for localized fouling monitoring. This thesis showed that the use of multivariate analysis of flame images and process data in combustion process is very promising. / Thesis / Master of Applied Science (MASc)

no / This paper presents results of a comprehensive investigation on the utilization of carpet waste fibers in reinforcement of clay soils. Effects of adding proportionate quantities of two different types of shredded carpet waste fibers to clay soils (i.e., 1, 3, and 5% by dry weight of the soil) were investigated and evaluated. The investigation was conducted on specimens prepared at their maximum dry unit weight and optimum moisture content, as well on specimens prepared at variable conditions of dry unit weight and moisture content. A comparison was also made on specimens prepared at the same fiber content by changing dry unit weight while moisture content was kept unchanged or by changing both dry unit weight and moisture content. The investigation revealed that inclusion of carpet waste fibers into clay soils prepared at the same dry unit weight can significantly enhance the unconfined compression strength (UCS), reduce postpeak strength loss, and change the failure behavior from brittle to ductile. The results also showed that the relative benefit of fibers to increase the UCS of the clay soils is highly dependent on initial dry unit weight and moisture content of the soil. Failure patterns were gradually transformed from the apparent classical failure for unreinforced soil specimens to barrel-shaped failures for reinforced specimens at 5% fiber content.

yes / A comprehensive experimental programme was performed with the focus on assessing the effects of compaction delay and ambient temperature on the physical, mechanical and hydraulic properties of lime treated expansive clays. Specimens were mellowed for a period of 0, 3, 6, 12, 24 and 48 h at two different temperatures of 20°C and 40°C prior to being compacted, tested and/or cured for up to 28 days for evaluating the impacts on long-term strength development. All specimens were prepared with the same dry unit weight of 12.16 kN/m3 and moisture content of 40% except for tests aimed at determining dry unit weight as a function of mellowing period. The results revealed that as the mellowing duration increased the dry unit weight declined remarkably at both temperature within the first 12 h. In addition, higher reduction rate was observed when specimens were mel-lowed at a temperature of 40°C. A 97% reduction in swelling pressure was obtained when the specimens were compacted upon mixing (zero hour mellowing period) and left to cure for 24 h prior to testing. Permeability coefficient of lime treated expansive clays was increased by up to 40 times when compaction was delayed for 24 h or when specimens were mellowed at 40°C. Specimens mellowed at a temperature of 40°C showed rela-tively stable values of permeability coefficient over the measurement period which could be attributable to accelerated pozzolanic reaction. The Unconfined Compressive Strength tests revealed that strength of lime treated expansive clays is significantly affected by compaction delay. An increase of 234% and 282% in the Unconfined Compressive Strength was achieved after 24 h of mixing with no compaction delay at 20°C and 40°C respectively. Gradual long-term gain in strength was observable within the 28 days post mixing but the rate of strength gain becomes slower and independent of temperature after the first 24 h of mixing. The results sug-gested that the four key reaction mechanisms occur concurrently with the first 12–24 h after lime addition recognized as being the most crucial period of time. Damaging the cementitious compounds by delayed com-paction is harmful to strength and restraining of swelling potential of lime treated expansive clays.

Land application of biosolids has been demonstrated to improve nutrient availability (mainly N and P) and improve organic matter in soils, but the effects of biosolids on C sequestration and N cycling in the Mid-Atlantic region is not well understood. The objectives were: 1) to investigate soil C sequestration at sites with a long-term history of biosolids either in repeated application or single large application; 2) to characterize and compare soil C chemistry using advanced 13C nuclear magnetic resonance (NMR) and C (1s) near edge x-ray absorption fine structure (NEXAFS) spectroscopic techniques; and 3) to compare biosolids types and tillage practices on short-term N availability in the Coastal Plain soils. Biosolids led to C accumulation in the soil surface (< 15 cm) after long-time application in both Piedmont and Coastal Plain soils. The C saturation phenomenon occurred in Coastal Plain soils, thus additional soil C accumulation was not achieved by increasing C inputs from biosolids to the Coastal Plain. Soil organic C from profiles in the field sites was not different at depths below the plow layer (15-60 cm). The quantitative NMR analyses concluded that O-alkyl C was the dominant form in the particulate organic matter (POM), followed by aromatic C, alkyl C, COO/N-C=O, aromatic C-O, OCH3 / NCH and ketones and aldehydes. The aliphatic C and aromatic C were enriched but the O-alkyl C was decreased in the biosolids-amended soils. The changes indicated that the biosolids-derived soil C was more decomposed and, thus, more stable than the control. The NEXAFS spectra showed that O-alkyl C was the dominant form in the POM extracted from biosolids-amended soils, followed by aromatic C, alkyl C, carboxylic C and phenolic C groups. These results were similar to those from NMR analysis. The regression and correlation analyses of C functional groups in the POM between NEXAFS and NMR indicated that both techniques had good sensitivity for the characterization of C from biosolids-amended soils. To evaluate short-term biosolids N availability, a three-year field study to investigate the effects of lime-stabilized (LS) and anaerobically digested (AD) biosolids on N availability in a corn-soybean rotation under conventional tillage and no-tillage practices was set up in 2009-2011. Results showed that both LS and AD biosolids increased spring soil nitrate N, plant tissue N at silking, post-season corn stalk nitrate N, grain yield, and soil total N by the end of the growing season. The same factors used to calculate plant available N for incorporated biosolids can be used on biosolids applied to no-till systems in coarse-textured soils. All these results indicated that the application of biosolids affects the long-term quantification and qualification of soil organic C and also improve short-term N availability in the Mid-Atlantic region. / Ph. D.

Reducing apple (Malus x domestica Borkh.) crop load during bloom is a reliable option for increasing fruit quality and return bloom. In this thesis, multiple approaches to improving bloom thinning practices are discussed. The first project analyzed the pollen tube growth of several crabapple cultivars. Previous research had improved the use of bloom thinning chemicals, by coordinating the application timing with the pollen tube growth between pollination and fertilization. However, pollen tube growth rates have only been measured in a few genotypes. In Chapter 2, the pollen tube growth rates of five crabapple cultivars were measured in the styles of 'Fuji', 'Golden Delicious', and 'Pink Lady' flowers, at four temperatures 12, 18, 24 and 30 C. Complex relationships were found among paternal pollen tube growth, maternal cultivar, and temperature. Chapters 3 and 4 describe projects where organically-approved chemicals, including the biofungicide, Regalia, were evaluated for their ability to simultaneously reduce crop load and decrease early season disease infection. These chemicals were applied in conventionally managed orchards (Chapter 3), and in an organically-managed 'Honeycrisp' orchard (Chapter 4). The number of chemicals approved for bloom thinning is limited, especially in the Eastern U.S. where lime sulfur and oil applications are not permitted during bloom. These studies indicate Regalia, applied during bloom, can reduce crop load and provide early season disease control. The research presented in this thesis provides new knowledge that can be incorporated into crop load management practices in both conventional and organic apple orchards. / Master of Science

To meet the requirements of precise temperature monitoring at high temperatures in extremely corrosive environments, such as in coal gasifiers, a new sensor technology has been developed. This optical, ultra high temperature measurement system utilizes single crystal sapphire as a sensing element. A series of experiments was performed to determine the corrosion resistance of single crystal sapphire and single crystal fully stabilized cubic zirconia at high temperatures in coal slag and soda lime glass. The amount of corrosion of sapphire and zirconia in corrosive slags was measured at 1200°C, 1300°C, and 1400°C for different exposure times. The microstructural features at the interface of sapphire and zirconia were investigated using SEM and EDX analysis. The experimental measurements as well as SEM micrographs show very little or no degradation of sapphire and zirconia samples in corrosive slags. An interesting phenomenon was observed in the EDX scans of sapphire in the coal slag: the iron from the slag appears to have completely separated from the silicon and deposited at the sapphire surface. This interesting observation can be further explored to study whether this iron layer can be used to control the corrosion of sapphire. / Master of Science

Trimethylamine, (CH3)3N, (TMA), odors are often associated with limed and polymer conditioned sludges. This odor has a fishy smell and can be a nuisance to the community surrounding a wastewater treatment plant or land application site. Several factors are thought to determine the amount of TMA generated from limed biosolids. These are, the presence of cationic polymer, the polymer dose, the time between addition of polymer and lime stabilization, shear imparted on the sludge in the dewatering process and dewatered cake solids concentration. All of these were investigated in this study. The results showed that TMA could be generated from sludge that did not contain polymer but the concentrations were low compared to sludge conditioned with cationic polymer. As the polymer dose increased, the TMA increased. Shear also showed to play an important role for TMA production. In addition to higher shear increasing the polymer demand, shear in itself can increase TMA generation. However, the most important factor in generating TMA was the time between conditioning and liming. If this time was minimized, little TMA was produced, even at high polymer doses. Data also suggests that methanogens play an important role in the breakdown of TMA. / Master of Science

No / The presence of free water in mortars destined for silo or bagged storage can lead to the degradation of the binder phase. Such water may be present as a result of using wet, as-delivered sand or as a consequence of prior processes such as de-activation of Roman cement. Thus, water must be removed from the system prior to storage. Part 1 of this paper describes the control of a technique by which quicklime is added to the wet system which principally dries it by both slaking the quicklime and evaporation as a consequence of the exothermic slaking reaction. Two examples of mortars are presented in which excess water is removed from the system by the inclusion of quicklime. In the first, the water is present in the as-delivered sand and the binder is a combination of the slaked lime and ggbs. In the second, the water remains after pre-hydration of a Roman cement which is a process to retard its rapid setting characteristics. It is shown that optimally dried mortars are not subject to degradation following storage of both mortar types. (C) 2015 Elsevier Ltd. All rights reserved.

Yes / This paper focuses on monitoring the evolution of lime-clay reactions using geotechnical parameters as a function of lime content and environmental temperature. Lime contents of 5, 7, 9, 11 and 13% by dry weight of expansive clay powder were added to prepare lime-clay specimens. The specimens were prepared at the same dry unit weight of 12.16 kN/m3 and moisture content of 40% except for tests aimed at the determination of dry unit weight as a function of mellowing period. Prepared specimens were mellowed or cured at two different ambient temperatures of 20 °C and 40 °C. Results attained from Unconfined Compressive Strength and permeability tests were employed to assess the impact of lime content on the mechanical and hydraulic properties of lime treated expansive clays. The results revealed that at the beginning, the rate of strength gain is remarkably fast for a particular period of time which is dependent on lime content. Furthermore, the strength gain on specimens cured at 40 °C is 8 times higher than that observed on specimens cured at 20 °C which highlights significant effect for the environmental temperature on accelerating the chemical reactions. Reduced dry unit weight due to increased resistance to compactability is observable with increasing lime content and higher environmental temperature. Accelerated pozzolanic reaction at higher environmental temperature resulted in permeability coefficient of specimens mellowed for 24 h at 40 °C to be higher than those mellowed at 20 °C. The results also highlighted that the permeability coefficient would be relatively stable when expansive clays were treated with small amounts of lime e.g. 5%.