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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Emissions of ammonia, nitrous oxide and methane during composting of organic household waste /

Gunnarsdotter Beck-Friis, Barbro, January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2001. / Härtill 5 uppsatser.
2

Composting of Human Excreta with Howard-Higgins Composting Method

Joelsson, Anna-Emilia January 2013 (has links)
Problems as a result of inadequate sanitation are the root to spreading of many diseases and the loss of several millions of lives every year. Therefore a Norwegian organization, Sustainable Sanitation Design, is trying out methods for having human feces sanitized in a sustainable way. In this trial, the safety and efficiency of composting human feces with a special composting method, called the Howard-Higgins method were investigated. The method claims to sanitize source separated feces in 90 days and to test that statement six compost containers were set up. To control that the composting process reached the heat necessary for sanitization the temperature was controlled frequently. Volatile solids, pH and the dry substance fraction were also controlled to measure Howard-Higgins method’s efficiency. By measuring fecal indicators Enterococcus feacalis initially and in the very end of the process, the statement of sanitization was controlled.  The results from the measuring of fecal indicators showed a very varied result. Some of the compost nearly reached the limits for pathogens set up by the WHO. The most successful compost ended up with 3.9 LOG10 reduction, which only 0.1 LOG10 below WHO’s definition of sanitization for excreta that is to be used as fertilizer. The least successful compost had only a 1.6 LOG10 reduction. None of the compost became warm enough to sanitize pathogens. The method is because of its complicity and uncertainty not recommended to be used by Sustainable Sanitation Design to sanitize human feces.
3

Compost stability : a comparative evaluation of respirometric techniques

Lasaridi, Konstadia Ekaterini January 1998 (has links)
No description available.
4

The biodegradation of broiler litter

Crawford, J. H. January 1981 (has links)
No description available.
5

Composting phosphorus fertilizer with organic wastes to stablize the fertilizer against fixation by phosphate-fixing soils

Francois, A. Joyce January 1987 (has links)
No description available.
6

Institutional Arrangements for Composting and Compost Use in Ho Chi Minh City, Vietnam

Yousif, Dave Faris January 2009 (has links)
The staggering levels of growth and development resulting in a more populous and affluent society that Vietnam is experiencing have resulted in greater levels of consumption and environmental damage from agricultural intensification (over-use of chemical fertilizers) and solid waste pollution. A traditional method touted as a modern solution is organic solid waste recycling and composting. This thesis seeks to determine the potential of compost use in Ho Chi Minh City, Vietnam based on a decentralized community-based composting scheme. In recent decades, in Vietnam and other developing countries, there has been an emphasis on large-scale, mechanized composting processes using mixed waste as the input material and technologies that are inappropriate for use in a developing country. These processes face high operational costs and a lower quality final product, leading to more problems than they promise to cure. This study examines three institutional models currently advocated in the literature to mange organic waste in developing countries: decentralization, privatization, public-private partnerships. This thesis focuses on how to redefine the manner in which organic waste is composted and concludes in favour of small-scale community-based composting. A small-scale community-based model currently in use in Quy Nhon, in central Vietnam is examined to determine its applicability in Ho Chi Minh City, Vietnam. The major contribution of this thesis is the use of institutional models (community-based management, decentralization, privatization, and public-private partnerships) to further understand the system of composting using municipal solid waste in developing countries. This understanding is used to present a framework that outlines the necessary institutional change to facilitate the development of initiatives that would manage organic solid waste.
7

Institutional Arrangements for Composting and Compost Use in Ho Chi Minh City, Vietnam

Yousif, Dave Faris January 2009 (has links)
The staggering levels of growth and development resulting in a more populous and affluent society that Vietnam is experiencing have resulted in greater levels of consumption and environmental damage from agricultural intensification (over-use of chemical fertilizers) and solid waste pollution. A traditional method touted as a modern solution is organic solid waste recycling and composting. This thesis seeks to determine the potential of compost use in Ho Chi Minh City, Vietnam based on a decentralized community-based composting scheme. In recent decades, in Vietnam and other developing countries, there has been an emphasis on large-scale, mechanized composting processes using mixed waste as the input material and technologies that are inappropriate for use in a developing country. These processes face high operational costs and a lower quality final product, leading to more problems than they promise to cure. This study examines three institutional models currently advocated in the literature to mange organic waste in developing countries: decentralization, privatization, public-private partnerships. This thesis focuses on how to redefine the manner in which organic waste is composted and concludes in favour of small-scale community-based composting. A small-scale community-based model currently in use in Quy Nhon, in central Vietnam is examined to determine its applicability in Ho Chi Minh City, Vietnam. The major contribution of this thesis is the use of institutional models (community-based management, decentralization, privatization, and public-private partnerships) to further understand the system of composting using municipal solid waste in developing countries. This understanding is used to present a framework that outlines the necessary institutional change to facilitate the development of initiatives that would manage organic solid waste.
8

Evaluation of an Aerobic Composting Process for the Management of Specified Risk Materials (SRM)

Zeng, Jian 24 January 2011 (has links)
In Atlantic Canada, approximately 8000 tonnes of Specific Risk Materials (SRM) is produced annually. Composting offers a means to partially treat and stabilize SRM. In this project, different types of agricultural residuals and wastes were used to compost with SRM in a pilot scale. The results were discussed based on the change in total carbon and nitrogen, pH, temperature, moisture content and electrical conductivity, which were measured at regular intervals over the study. The temperature for all treatments met the CCME pathogen control guideline. The maturity test showed that the CO2-C in all the compost was less than 1 mg/g organic matter/day. Straw and other agricultural wastes performed well in the composting SRM, other advantages includes greater availability, lower cost and more easily decomposed carbon compounds.
9

Evaluation of In-House Windrow Composting as a Poultry Litter Treatment Prior to Land Application

Winkler, Scott 16 December 2013 (has links)
The land application of poultry litter as a fertilizer is a common practice due to the low cost and high availability of poultry litter in some regions. However, land application can create concerns related to runoff water quality and odor. An experiment was conducted to determine the effectiveness of in-house windrow composting (IWC) of poultry litter prior to land application in terms of bacteria, odors and nutrients compared to untreated (fresh) litter. In the second part of the research, the objective was to quantify the number and distribution within poultry houses of selected water quality indicator bacteria in litter. Comparison of fresh and IWC litter showed that Escherichia coli (E. coli) was present in very low concentrations on day 1 in fresh litter (20 cfu/g) and IWC litter (55 cfu/g), but the levels were undetectable in both litter types on day 9 in Trial 1. In Trial 2, E. coli levels were undetectable in IWC litter before and after the IWC process. Similarly, fresh litter had undetectable E. coli levels on day 1, but 185 cfu/g on day 10. Additionally, nutrient analysis and moisture content results showed no significant differences between fresh and IWC litter. To evaluate odor differences between fresh and IWC litter, volatile gases were collected onto sorbent tubes and into Tedlar bags from wind tunnel flux chambers placed directly on litter piles prior to land application. The concentrations of 13 compounds commonly associated with animal manure were then determined by GC/MS. Analysis of volatile gas samples resulted in significant changes of various individual odorants, while olfactometry analysis of Tedlar bag air samples resulted in reduced detection threshold values for IWC litter compared to the fresh litter. These results indicate the possible mitigating effects IWC may have on odors associated with litter. In the survey of bacterial distribution within poultry houses, litter counts varied greatly within house sections and between farms. Regression analysis revealed that bacterial counts and litter moisture content are significantly related, thus explaining much of the variation in litter bacterial counts within a house. These results indicate that IWC could be a useful best management practice to reduce E. coli levels and odor associated with poultry litter prior to land application, but factors such as moisture content, initial bacteria concentrations, and windrow size all affect the level of bacteria and odor reduction.
10

Aerobic thermophilic digestion of model agricultural wastes

Ugwuanyi, Jeremiah Obeta January 2000 (has links)
No description available.

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