This thesis aims to gas installation of the coal boiler and its thermal recount. In the first part, there is implemented calculation of the combusting chamber. After that follows the recalculation of heat exchange surfaces and proposal tube air heater, which will replace the existing air heater Ljungström. The emphasis is placed on the preservation of the exsiting steam parametrs and keeps emission limit of NOx.

In this dissertation, we analyze the Life Cycle Assessment (LCA) of the Steam Sterilizer, popularly known as Autoclave. The LCA will help Getinge Sterilization AB to identify the stages of the life cycle of Autoclave model GSS-P 91413, which contributes more to the environmental footprint. We use the ISO 14040 LCA framework to conduct the Cradle to Grave boundary study of the Autoclave. The results have shown the use phase to be a dominant phase with almost 84% of carbon footprint. For Getinge to produce sustainable products and reach its long-term goal of becoming carbon neutral, they need to reduce its environmental footprint in every phase of the product life cycle. Thus, this report suggests the best way that the company can impact the changes to the users even though they have very little control over it. The results were obtained using the Sustainable Minds (SM 2013) software, which is ISO certified, henceforth the results are trustworthy. This Thesis has 8 parts: Introduction, Method, Theory, Results, Conclusion, Critical Review, References, and Appendices.

This analysis calculates the velocity profile and recirculation ratio in the aspirator region of an enhanced once-through steam generator of the Babcock & Wilcox design. This information is important to the development of accurate RELAP5 models, steam generator level calculations, steam generator downcomer models, and flow induced vibration analyses. The OpenFOAM CFD software package was used to develop the three-dimensional model of the EOTSG aspirator region, perform the calculations, and post-process the results. Through a series of cases, each improving upon the modeling accuracy of the previous, insight is gained into the importance of various modeling considerations, as well as the thermal-hydraulic behavior in the steam generator downcomer. Modeling the tube support plates and tube nest is important for the accurate prediction of flow rates above and below the aspirator port, but has little affect on the aspirator region itself. Modeling the MFW nozzle has minimal influence on the incoming steam velocity, but does create a slight azimuthal asymmetry and alter the flow pattern in the downcomer, creating recirculation patterns important to inter-phase heat transfer. Through the development of a two-phase solution that couples the aspirated steam and liquid feedwater, it was found that the ratio of droplet surface area to volume plays the most important role in determining the rate of aspiration. Calculations of the velocity profile and recirculation ratio are compared against those of historical calculations, demonstrating the possibility that these parameters were previously underpredicted. Such a conclusion can only be confidently made once experimental data is made available to validate the results of this analysis. / Master of Science

The current research investigates the utilization of cotton gin waste as a feedstock to produce a value-added product - fuel ethanol. Cotton gin waste consists of pieces of burs, stems, motes (immature seeds) and cotton fiber, and is considered to be a lignocellulosic material. The three main chemical constituents are cellulose, hemicellulose, and lignin. Cellulose and hemicellulose are polysaccharides of primarily fermentable sugars, glucose and xylose respectively. Hemicellulose also includes small fractions of arabinose, galactose, and mannose, all of which are fermentable as well. The main issue in converting cotton gin waste to fuel ethanol is the accessibility of the polysaccharides for enzymatic breakdown into monosaccharides. This study focused on the use of steam explosion as the pretreatment method. Steam explosion treatment of biomass has been previously described to increase cellulose accessibility. The governing factors for the effectiveness of steam explosion are steam temperature and retention times. The two factors are combined into a single severity term, log(Ro). Following steam explosion pretreatment, cotton gin waste was subjected to enzyme hydrolysis using Primalco basic cellulase. The sugars released by enzyme hydrolysis were fermented by a genetically engineered Escherichia coli (Escherichia coli KO11). The effect of steam explosion pretreatment on ethanol production from cotton gin waste was studied using a statistically based experimental design. The results obtained from this study showed that steam exploded cotton gin waste is a heterogeneous material. Drying and milling of steam exploded cotton gin waste was necessary to reduce variability in compositional analysis. Raw cotton gin waste was found to have 52.3% fermentable sugars. The fiber loss during the steam explosion treatment was high, up to 24.1%. Xylan and glucan loss from the pretreatment was linear with respect to steam explosion severity. Steam explosion treatment on cotton gin waste increased the hydrolysis of cellulose by enzyme hydrolysis. Following 24 hours of enzyme hydrolysis, a maximum cellulose conversion of 66.9% was obtained at a severity of 4.68. Similarly, sugar to ethanol conversions were improved by steam explosion. Maximum sugar to ethanol conversion of 83.1% was observed at a severity of 3.56. The conclusions drawn from this study are the following: steam explosion was able to improve both glucose yields from enzyme hydrolysis and ethanol yields from fermentation. However, when analyzed on whole biomass, or starting material basis, it was found that the fiber loss incurred during steam explosion treatment negated the gain in ethanol yield. / Master of Science

Steam exploded fibers from Yellow Poplar (Liriodendron tulipifera) wood were assessed in terms of (a) their impact on torque during melt processing of a thermoplastic cellulose ester (plasticized CAB); (b) their fiber incorporation and dispersion characteristics in a CAB-based composite by SEM and image analysis, respectively; and (c) their impact on the mechanical properties (under tension) of CAB-based composites having fiber contents of between 10 and 40% by weight. The fibers included water-washed steam exploded fibers (WEF), alkali-extracted fibers (AEF), acetylated fibers (AAEF), all from Yellow poplar (log Ro = 4.23), and oat fillers (COF) as control. The stepwise increase in cellulose content by extraction, and especially the (surface) modification by acetylation, contributed to increased torque during melt processing, and to improved interfacial adhesion as well as fiber dispersion. As compared to pure CAB, AAEF generated the highest increase in torque (+ 421%) followed by AEF (+ 260%) and WEF (+ 190%) at 40% fiber content by weight. AAEF was also found to enhance the tensile properties of the resulting composites. SEM studies of the tensile fracture surfaces indicated significant interfacial delamination and also pull - out of fibers when WEF, AEF, and COF were used to reinforce the CAB matrix. Composites with AAEF, by contrast, revealed fracture surfaces with reduced interfacial delamination and with significant fiber fracturing during failure. Image analysis was used to determine fiber dispersion within the resulting composites quantitatively. Significant improvement in fiber dispersion was achieved when the matrix was reinforced with acetylated fibers (AAEF). Fiber addition to the matrix resulted in loss of strain at break (- 80 to - 93%) and slight or significant increases in modulus (+ 47 to + 103%) depending on fiber type at 40% fiber content. Maximum stress declined for all fibers except AAEF at all fiber contents. AAEF-based composites revealed a decline in maximum stress when fiber content rose to 10%, and this reversed when fiber content increased beyond 10%. This increase in strength is consistent with the rule of mixtures that stipulates reinforcement of the matrix by fibers that are capable of transferring stresses across the fiber-matrix interface. All fibers suffered length decreases during melt processing. / Master of Science

Recent developments in educational practices have identified the teaching of STEM (science, technology, engineering, and mathematics) areas as important, but this emphasis on STEM fields has sacrificed educational focus on the Arts (Cohen, 2016). This is a significant loss, not only in terms of the loss of humanities education in itself, but through the potential loss of foundational skills through practice in artistic areas. The current paper explores this idea by investigating the correlational relationship between visual spatial abilities and participation in a variety of creative activities. Spatial ability is known to be a cognitive skill that underlies success in STEM related disciplines. Though numerous studies have explored spatial ability, no much is known about how individual differences in spatial ability arise. One possible area of inquiry is personal hobbies. It seems likely that creative hobbies that involve spatial-cognitive mechanisms would increase spatial ability. Knowledge gained concerning the relationship between spatial ability and creative pursuits may not only support education within artistic fields, but also within science, academia, and industry. If there is a relationship between frequent engagement in creative activities increased spatial abilities, we will have a stronger case for not cutting Arts education and can potentially provide a new approach to STEM pedagogy. The intent of the proposed study is to look at the connection between the frequency of engaging in eight extracurricular activities (e.g. literature, music, arts-and-crafts, creative cooking, science and engineering, sports, visual arts, and performing arts) and whether or not engagement in these activities correspond with increases in spatial ability.

No description available.

M.S.

A typical failure in a heat exchanger is the breakdown of a tube due to impact-sliding wear. We investigate the dynamic behavior of a tube subjected to cross flow and study the stability of periodic solutions, bifurcations, and the route to chaos. The fluid-stiffness-controlled mechanism is chosen to represent the fluid forces and the impact forces are modeled by a piece-wise-Iinear spring. A two-point boundary-value algorithm is used to calculate periodic solutions and Floquet theory is used to study their stability. Poincare sections and bifurcation diagrams are used to study non-periodic solutions. Furthermore. for this autonomous system, the method of harmonic balance appears to be less suited than the two-point boundary-value algorithm for calculating periodic motions. For the case of a single-mode approximation. the results show that the tube undergoes relaxation oscillations and hence no bifurcations occur for fluid velocities ranging from 1.1 Ve to 3.0 Ve, where Ve is the critical fluid velocity. For the cases of two- and three-mode approximations. the results show that periodic solutions undergo bifurcations leading to chaos. Consequently. we conclude that chaos is the result of modal interactions. Observing the details of impacts. we also conclude that chaos appears when a second impact occurs on the same stopper. We also found intermittent chaos alternating with transient periodic motions. Lastly, we estimate the mean impact forces and mean impact-sliding wear work rates and compare them with previous results. / Master of Science

Yes / In oil, gas and petrochemical production complexes, steam pressure boosting technology is used to recover low-pressure steam, using both mechanical and thermal solutions to increase energy efficiency. The heat recovery from steam, especially flash steam produced in the return condensate lines, can be considered an economic and attractive solution. In an industrial case study in a gas plant located in the south-west of Iran, the LP condensate returns to the LP condenser waste with a flow rate of 96,000 kg/h and a pressure of 0.45 bar. As a result of the pressure drop, about 6800 kg/h of flash steam is generated. Therefore, in order to recover, the first the return condensate current enters a flash drum to separate the amount of steam produced by the flash operation. In this research, two strategies for increasing the pressure using a steam compressor and an ejector have been investigated. The simulation results show that flash steam recycling using steam compressors and ejectors results in energy saving for the refinery of about one million and USD100k per year, and also about 152 and 137 thousand tons equivalent to carbon dioxide emissions per year are reduced, respectively.