No description available.

No description available.

No description available.

No description available.

Master of Science / Department of Mechanical Engineering / Donald L. Fenton / This project was done to determine the effectiveness of different methods of mitigating the effects of an ammonia release through a pressure relief device in an ammonia refrigeration system. Several methods were considered, and five were selected for further study. The methods chosen for further study were discharge into a tank containing standing water, discharge into the atmosphere, discharge into a flare, discharge into a wet scrubber, and an emergency pressure control system. Discharge into a tank containing standing water is the most common method in existence today but several people in the ammonia refrigeration industry have questioned its reliability. The methods were compared based on a quantitative risk analysis, combining failure rates of each system with ammonia dispersion modeling and the monetized health effects of a system’s failure to contain an ammonia release. It was determined that the release height had a greater influence on the downwind cost impact than any other variable, including weather conditions and release from multiple sources. The discharge into a tank containing standing water was determined to have the lowest failure rate, while the flare system was found to be the most effective in terms of relative overall release consequent cost. The emergency pressure control system is now required by the codes, and any of the other mitigation systems would be very effective when used in conjunction with the emergency pressure control system.

Call number: LD2668 .T4 1979 H36 / Master of Science

Call number: LD2668 .T4 1984 H38 / Master of Science

Master of Science / Department of Agronomy / David B. Mengel / Anhydrous ammonia (AA) is one of the most commonly used nitrogen (N) fertilizer sources for corn (Zea mays L.) in the US. Traditional knife applicators are slow, have high power requirements and create substantial soil disturbance. Thus, there is considerable interest in high speed, shallow placement, and low draft AA applicators like the newly introduced JD 2510 series, particularly for no-till production systems. The objective of this project was to compare a prototype high speed, low draft applicator (JD) with a traditional knife type AA applicator (TRAD) for irrigated and dryland corn production in the Kansas River Valley. Field studies were conducted from 2007 through 2009. Six N rates ranging from 0 – 224 kilograms N per hectare, in 45 kilogram increments, were applied at 3 application timings, Fall (FALL), Preplant (PRE), and Sidedress (SD) with both type applicators. Gaseous AA emissions were collected over a seven to nine day period after each application for both the TRAD and JD applicators for all application timings. The impact of applicator, timing and N rate was also measured on plant stand, earleaf N content, total N uptake, nitrogen use efficiency and grain yield. Statistically higher post application losses of ammonia at high N application rates were seen at all application timings with the JD applicator. However, these N losses were not of agronomic significance, and did not affect grain yield in 2007 or 2008. In 2009, there did appear to be a significant difference between applicators in grain yield, however this was primarily due to a significant yield decrease at the JD SD 224 kilograms N per hectare treatment from high application loss and resulting plant tissue damage. A significant response to N application was seen every year. Optimum N rate varied between years. FALL and PRE treatments had significantly higher grain yield than SD applications in 2008. However, in 2009 there was no significant difference in N application timing.

Gaseous ammonia emissions from livestock production are a well known source of anthropogenic ammonia emissions and have been the subject of numerous studies in Western Europe and in the United States of America. They are deemed responsible for the acidification of ecosystems. Furthermore, ammonia emissions from intensive livestock operations located in the vicinity of major cities induce favourable conditions for smog formation. Ammonia volatilization from manure also reduces its effectiveness as a fertilizer by reducing its nitrogen content, an important nutrient for plant growth. Certain technologies and structures exist to cover manure storage tanks in order to limit these ammonia losses to the atmosphere. Very few studies have been done in Canada where climate and manure management practices differ widely from those in Western Europe and in the United States of America. In this project, a measurement campaign was financed by Agriculture and Agrifood Canada on four commercial livestock production infrastructure to begin the development of national ammonia inventory. Commercial dairy and swine manure storages covered by floating geomembranes were monitored for periods exceeding six months in the Eastern Townships of Quebec. The swine manure storage emitted negligible amounts of ammonia, from 5.9 ?10[superscript -3] to 0.14 [micro]g? m[superscript -2] . s[superscript -1] over the summer time. The dairy manure storage emitted more substantial amounts of ammonia when the manure surface was frozen in winter, from 1.9 to 16 [micro]g. m[superscript -2] ? s[superscript -1], then when unfrozen, 93 to 166 [micro]g? m[superscript -2] ? s[supercript -1]. A structural difference in the covering technology at the dairy manure storage rendered it less airtight than the swine manure storage. Therefore, the efficiency of a cover to limit ammonia emissions from manure is function of its air tightness. Ammonia emission rates from two tie-stall commercial dairy buildings were also monitored in the Eastern Townships of Quebec. Ammonia emission measurements done at building A during winter 2007 ranged from 3.77 to 6.80 g ? day[superscript -1] ? animal[superscript -1] while those performed at building B during summer 2007 were higher and ranged from 11.33 to 18.20 g ? day[superscript -1] ? animal[superscript -1]. These values fall within the wide range of those published for Western Europe and the United States of America. However, unlike studies completed in Europe using similar procedures, the methods used to measure gaseous ammonia concentrations and building ventilation flow rates in this study were validated in controlled environments.

Ammonia and water are major components of many planetary bodies, from comets and icy moons such as Saturn's Titan to the interiors of the planets Neptune and Uranus. Under a range of high pressures and/or low temperatures known to occur in these planetary bodies, ammonia and water form a series of compounds known as ammonia hydrates. Ammonia and water form three stoichiometric compounds, ammonia hemihydrate, ammonia monohydrate and ammonia dihydrate, which have ammonia-to-water ratios of 2:1, 1:1 and 1:2 respectively. Therefore a good understanding of the three stable ammonia hydrates is required for modelling the interiors of these bodies. Additionally, the ammonia hydrates are the simplest systems to incorporate mixed (N-H O and O-H N) hydrogen bonds. Such bonds are important biochemically, and along with O-H O H-bonds, mixed H-bonds are responsible for the second-order structure of DNA, and they are also responsible for the proton transfer reactions in enzymic processes. The understanding of these bonds and processes rests on the knowledge of the relationship between bond strength and geometry, and the ammonia hydrates provide a rich range of geometries against which models of such mixed H-bonds can be tested. X-ray and neutron diffraction techniques have been used to investigate the behaviour of the ammonia-water complex and further the understanding of this system. This includes solving the structure of a phase which was previously thought to be an ammonia monohydrate phase, but has been shown here to be a mixture of an ammonia hemihydrate phase and Ice VII. In addition to this, x-ray and neutron diffraction experiments have been performed to explore how this phase behaves under changing pressure and temperature conditions, and what other implications that this has on the ammonia-water system. It has been found that ammonia hemihydrate can also form a structural phase observed to form in both ammonia monohydrate and ammonia dihydrate within the same pressure and temperature regime, which opens the possibility of a solid solution existing between all three stoichiometric ammonia hydrates.