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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.
121

Composting | KC

Rostek, Andrew January 1900 (has links)
Master of Landscape Architecture / Landscape Architecture/Regional and Community Planning / Jason S. Brody / Kansas City is currently under achieving in its capacity of divert recyclable and compostable solid waste from city landfills. The city recycling system provides free access to single family residents, but it does not provide access to high density residential and commercial land uses commonly found Downtown. To solve this dilemma, KCDC has studied the current solid waste systems in the city, and developed its [re]considered proposal through a MARC Solid Waste Management District grant to improve Kansas City waste diversion. This is achieved through a system of links, clusters and nodes which will help to promote and facilitate greater recycling (KCDC 2015 Fall Studio 2015) Compost | KC seeks to answer if the organic nodes as proposed in can effectively compost residential organic waste in down town Kansas City. As part of this system, the organic node at 12th and Holmes functionally demonstrates the potential feasibility and benefits of residential compost of organic solid waste. Through the site design, the proposed organic node creates an integrated system of residential organic waste collection, processing and utilization. Collected form a 15 minute radius the waste is processed into a rich organic compost that is used in various ways to improve soil quality for stormwater management, carbon sequestration, and increased biomass production in and around the site. To compost the organic waste, the site contains a series of in-vessel composting drums, agitated compost piles connected to greenhouses, and an external maturing pile visibly demonstrating and educating the public composting benefits. Managed through a local non-profit organization, compost is used to grow a variety of produce and nursery stock sold to help fund the site management. Organic waste is brought to the site by organized collection with apartment complexes and free public drop-off points. By incentivizing access, ease and appeal of composting in Kansas City for residences, the organic node at 12th and Holmes achieves the goals of both the site design and [re] considered proposals. By meeting those goals, the organic node helps to increase organic waste diversion and increase education and awareness about the benefits of composting in downtown Kansas City.
122

An Autothermal, Representative Scale Test Of Compost Heat Potential Using Geostatistical Analysis

McCune-Sanders, William J 01 January 2018 (has links)
Composting has been practiced for thousands of years as a way of stabilizing and recycling organic matter into useful soil amendments. Thermophilic compost releases significant amounts of heat at temperatures (~140 °F) that are useful for environmental heating or process water. This heat has been taken advantage of in various ways throughout history, but development of a widely adopted technology remains elusive. The biggest barrier to adoption of compost heat recovery (CHR) systems is projecting accurate, attractive economic returns. The cost of transfer equipment is significant, and with variability in composting substrates and methods, it is difficult to predict the power and quality of heat a proposed system would produce. While the ultimate heat release may be calculated with standard techniques, the dynamics of compost temperature and thermal power are less understood. As heat yield is one of many goals, better understanding of compost’s thermal dynamics is important for CHR optimization. This research addresses the issue by developing a field test that measures heat release and temperature across a representative-scale compost volume. The compost test vessel was built from common construction materials and insulated enough to be self-heating in cold weather. A 4’ x 4’ x 4’ cube of 2” foam insulation panels held 1.812 cubic yards of active compost, intermittently aerated at ~35 CFM. Data from 84 temperature sensors, and one pressure sensor at the blower, was logged at 1-minute intervals for a period of 35 days. Spatial temperature fields were estimated by Kriging, and used to calculate conductive heat loss and compost volume temperature over time. Enthalpy loss was calculated using the blower pressure curve, temperature data and humidity assumptions. The compost exhibited wide variation in temperature and heat flow over time, and less horizontal symmetry than expected. The results are dynamic and best viewed graphically. Enthalpy loss varied with adjustments to the aeration cycle, ranging from 100 to 550 W (60-minute average rates), while conductive losses were in the range of 75 W. Peak sustained thermal output was around 600 W (500 W by aeration) from days 11-13 with about 0.6 yd3 of compost in the thermophilic zone; however, this cooled the compost significantly. Aeration was then reduced, and the compost temperature recovered, with 50% - 90% of the compost volume above 130 °F from days 14-23; during this period, total heat loss was around 150 - 200 W with aeration loss around 60-100 W. The test was successful in producing hot compost and building temperature field and heat loss models. However representative aeration rates cooled a large amount of the compost volume as cool air was drawn into the vessel. Aeration rate reduction accomplished desired compost temperatures, but resulted in low enthalpy extraction rate and temperature. Future work will address this issue with the ability to recirculate air through the compost.
123

Use of compost filter bermsfor sediment trapping: primary focus on water quality and structural stability

Raut Desai, Aditya Babu 15 November 2004 (has links)
Runoff from road construction and maintenance sites is responsible for erosion and deposition of sediments in the receiving water bodies. In addition to soil particles from erosion, runoff also transports other pollutants such as rubber, toxic metals, automobile fluids, car exhausts (which settle with the rain), pesticides, fertilizers, and other debris. Compost has been used effectively as a valuable soil amendment to aid plant growth. Berms (mounds) of compost placed at the top or bottom of steep slopes can be used to slow the velocity of water and provide additional protection for receiving waters. However, a downside of the application of composted organic material is the potential degradation of runoff water quality. Overloading with nitrogen and phosphorus causes eutrophication, which reduces the suitability of waterways for beneficial uses. A field testing of the berms coupled with a laboratory analysis of the testing water will provide a basis for the impact of the compost berms on the runoff water quality. The study of the impact of compost on the runoff water quality was investigated. The objective of this study was to evaluate the performance of berms made from various materials such as dairy manure compost, yard waste compost and composted bio-solids mixed with wood chips in a ratio of 50:50 on the runoff water quality, as well as, the sediment removal efficiencies. Field tests were performed on the berms to simulate conventional rainfall runoff and the tested water was collected as time-weighted samples and analyzed in the laboratory. Several variables were investigated during this study. Results of this investigation demonstrated that the effectiveness of this application was hampered by the structural instability of the berm. A 100% failure rate was observed in the berms tested. Optimum performance was observed in yard waste compost berms, which introduced the least amount of contaminants into the water. However, some masking effect could be present due to berm failures. In fact, the actual sediment removal by the berms could not be determined. The study of compost filter berms showed some evidence of the existence of first flush effect.
124

Toxic secondary metabolite production by thermophilic fungi of feedlot compost and silage

Rogers, Laurence C. 03 June 2011 (has links)
Extensive research has been compiled on mycotoxin production by mesophilic fungi. However, toxin production by the thermophilic fungi has only slightly been explored. In 1970 Sister Donovan of this laboratory hinted at the possibility of mycotoxin production in thermophiles when she demonstrated that extracts of Fenicillium duponti were toxic towards brine shrimp (Artemia,salina).Thermophilic fungi from natural composting substrates and from existing laboratory stock cultures were investigated to determine the possibility of mycotoxin production by thermophilic fungi. Three bioassay organisms were used to test the toxicity of the thermophilic fungi extracts.Sixteen of the 16 thermophiles reduced brine shrimp viability by more than 25% over controls. Ten of the 16 thermophiles produced toxic substances at each of three fungal incubation temperatures.Germinating Bacillus megatherium spores were found sensitive to extracts of 9 of the 16 thermophiles. Five of the nine thermophiles produced bacterial toxic substances at each of three fungal incubation temperatures.All embryos exposed to the thermophilic extracts lived and developed normally showing no sign of somatic deformities upon opening the eggs. One-day-old hatched chicks were then investigated. Sixteen of the 48 chicks injected with thermophilic extracts manifested viscerallesions of the heart, liver and stomach on autopsy seven days after injection.Results of three bioassays indicate that the toxic secondary metabolites were found to be present in crude extracts of 16 thermophilic fungi. Data indicated that many of the thermophiles produced toxic substances at each of three incubation temperatures.Ball State UniversityMuncie, IN 47306
125

Development of refuse and wastewater treatment processes for kitchen waste

Mang, Meng-Tsung 26 August 2004 (has links)
Kitchen waste is the certain man-made trash in our daily life. It is mainly the water and oil, which is easy to decompose. In Taiwan, there is about 20,000 metric tons of family rubbish everyday, and approximately 20% to 30% of the rubbish is organic substance. Moreover, kitchen waste has a significant contribution on the total amount of rubbish. Thus, reduction and recycling of kitchen waste becomes an important issue, and it needs to be solved immediately. According to the article of Water Pollutant Prevention Act revised by Environmental Protection Bureau on 26 April 2000, wastewater discharges from apartment buildings need to be treated to meet the discharge standards. Furthermore, the discharge standards will be even more stringent in the near future. Kitchen wastewater includes liquids of kitchen rubbish, liquid of waste oil, and wastewater from grinding machines for food waste crushing. If all of the above polluting wastewater is discharged directly to the sewer system, the cost for sewer system maintenance would be huge. To protect the ecosystem and to minimize the cost of sewer system maintenance, kitchen waste and its wastewater need to be effectively treated. In this study, a kitchen waste treatment system is designed and constructed. This system is able to treat kitchen wastewater efficiently and effectively. Moreover, this system is easy to operate and maintain with less maintenance cost. The treated wastewater could meet the discharge standards with 91.4% of suspended solid removal, 91% of chemical oxygen demand (COD) removal, 96.7% of biochemical oxygen demand (BOD) removal, and 100% of grease removal.
126

Valuating and Analyzing the People for Willingness to Pay of Food Waste Recycling and Reusing-A Case Study of Kaohsiung and Taichung City

Chen, Li-chain 16 August 2005 (has links)
Food waste is one of an organic waste and contains the value of recycling and reusing. EPA shows that there are almost the amount of 4500 tons food wastes which is about 36~64% in households in Taiwan everyday. Therefore, if food wastes could be reused again, not only greatly reducing the amount of waste, decreasing the problem of odor from progressing food wastes, but also increasing the using year of landfills and incinerators. Furthermore, it can develop fully the value of multiple reusing in recycling. The study is forced on questionnaires for the residents of the city of Kaohsiung and Taichung, to know the present of recycling of food waste and its difficulty in executing a strategy. Conferring the willingness to pay and the willingness to accept of food waste recovery and if the price is different or not by Contingent Valuation Method (CVM), and moreover evaluating the potential benefit. The results of the study are as following: there are conspicuous difference in ¡§if doing something about recovery¡¨ ¡§the way of recovery¡¨ and ¡§if see any inspectors examine the classification of refuse¡¨. The most difficulties of recovery food waste in both cities are ¡§its odor and breed mosquito and fly easily¡¨ and ¡§not knowing clearly what materials should be recovered or not¡¨. About the price of the willingness to pay and the willingness to accept, the major answer shows ¡§No, I would not.¡¨ from this questionnaires. On the other hand, answers of ¡§Yes, I would like.¡¨ all hope that the pay less is better and the compensation more is better. The price of the willingness to pay of Kaohsiung residents is NT$ 41.8 dollars, and Taichung residents is NT$ 45.3 dollars. Otherwise, the higher environmental conscious the Kaohsiung residents have, the higher willing to pay. At the same time, the difficulty of recovery food waste is low comparatively. In addition, ¡§occupation¡¨ ¡§family revenue per month¡¨ ¡§cooking per week¡¨ have effect on the price of the willingness to pay and the willingness to accept. In the result of regression, some of variable parameters could affect the price of the willingness to pay. It maybe provides society for reference according the benefit in the estimating of regression. Therefore, the study hopes to provide the decision-maker more clear environmental and economical information through evaluate and analyze the willingness of pay of food waste. Furthermore, it maybe help the government to make a future policy in order to practice the food waste recovery indeed and carry out the target of reducing the amount of waste and resources recovering for a sustainable resources of food waste.
127

Use of compost filter bermsfor sediment trapping: primary focus on water quality and structural stability

Raut Desai, Aditya Babu 15 November 2004 (has links)
Runoff from road construction and maintenance sites is responsible for erosion and deposition of sediments in the receiving water bodies. In addition to soil particles from erosion, runoff also transports other pollutants such as rubber, toxic metals, automobile fluids, car exhausts (which settle with the rain), pesticides, fertilizers, and other debris. Compost has been used effectively as a valuable soil amendment to aid plant growth. Berms (mounds) of compost placed at the top or bottom of steep slopes can be used to slow the velocity of water and provide additional protection for receiving waters. However, a downside of the application of composted organic material is the potential degradation of runoff water quality. Overloading with nitrogen and phosphorus causes eutrophication, which reduces the suitability of waterways for beneficial uses. A field testing of the berms coupled with a laboratory analysis of the testing water will provide a basis for the impact of the compost berms on the runoff water quality. The study of the impact of compost on the runoff water quality was investigated. The objective of this study was to evaluate the performance of berms made from various materials such as dairy manure compost, yard waste compost and composted bio-solids mixed with wood chips in a ratio of 50:50 on the runoff water quality, as well as, the sediment removal efficiencies. Field tests were performed on the berms to simulate conventional rainfall runoff and the tested water was collected as time-weighted samples and analyzed in the laboratory. Several variables were investigated during this study. Results of this investigation demonstrated that the effectiveness of this application was hampered by the structural instability of the berm. A 100% failure rate was observed in the berms tested. Optimum performance was observed in yard waste compost berms, which introduced the least amount of contaminants into the water. However, some masking effect could be present due to berm failures. In fact, the actual sediment removal by the berms could not be determined. The study of compost filter berms showed some evidence of the existence of first flush effect.
128

Implementation of sustainable management practices at two California Central Coast vineyards and their effects on soil fertility a thesis /

Stimson, Dawn M. Hallock, Brent G. January 1900 (has links)
Thesis (M.S.)--California Polytechnic State University, 2009. / Title from PDF title page; viewed on December 2, 2009. Major professor: Brent G. Hallock, Ph.D. "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Agriculture with specialization in Soil Science." "November 2009." Includes bibliographical references (p. 67-71). Also available on microfiche.
129

Evaluation of composted poultry litter use in horticulture

Marble, Stephen Christopher. Sibley, Jeffrey Lynn, Gilliam, Charles Homer, January 2009 (has links)
Thesis--Auburn University, 2009. / Abstract. Includes bibliographic references.
130

Optimising nutrient potential from compost and irrigation with wastewater to meet crop nutritional requirements

Chipula, Grivin January 2013 (has links)
Globally agricultural production is facing serious challenges to provide adequate food supply to meet a growing population. However, the reduced capacity of soil to support and sustain agricultural production as a result of soil fertility decline is impacting negatively on agricultural growth. Increase in the price of inorganic fertilisers and limited availability of nutrients from organic amendments has reduced progress in improving soil fertility. This research therefore aims at contributing knowledge towards evaluating the maximisation/optimisation of nutrients in compost and secondary treated sewage effluent (STSE) amended soils to meet the nutritional requirements of crops for sustainable crop production and environmental protection. STSE was irrigated on soils (sandy loam and clay loam) amended with greenwaste compost in soil incubation, glasshouse/pot and lysimeter studies. Perennial ryegrass (Lolium perenne) was grown in the pots and lysimeter studies. The incubation experiment showed that for a clay loam, N mineralisation in treatments with STSE alone and combinations of compost and STSE was higher than the applied N. Increasing compost quantity in compost and STSE nutrient integration resulted in reduced net N mineralisation in the clay loam soil. In the sandy loam, increasing compost contribution in compost and STSE nutrient integration resulted in an increase in net N mineralisation. Cation exchange capacity, microbial diversity, quality of available carbon and drying and rewetting cycles influenced the net nitrogen mineralisation dynamics in both soil types. Increasing the contribution of STSE while reducing compost quantity resulted in increased nitrogen use efficiency and ryegrass dry matter yield. The environmental threat to ground and surface water pollution through NO3 --N leaching may be enhanced by the inclusion of STSE in integrated compost and STSE nutrient supply to plants. Similarly, the threat to eutrophication due to phosphorous leaching is likely to be higher with integration of compost and STSE. Ryegrass dry matter yield reduced with increasing compost contribution while the concentration of N in ryegrass herbage for the combinations of compost and STSE was above the minimum requirement for N in herbage for productive grazing and dairy cattle in the pot experiment. Using compost and STSE of similar characteristics, the ideal approach to maximise nutrient potential from compost through irrigation with STSE is when 25% compost is integrated with 75% STSE with respect to nitrogen supply.

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