Emission of greenhouse gases during composting of deep litter from pig production – effect of straw content

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Of the anthropogenic greenhouse gas emission in Denmark animal manure contributes an estimated
40% of methane (CH4) and 20% of nitrous oxide (N2O). Livestock production systems undergo
changes for the purpose of increasing animal welfare, and such changes often include increasing the
amounts of bedding manure. Emission of greenhouse gases from composting pig deep litter was
studied during a 4-month period. Effects of increasing the amount of straw used in deep litter
(reducing litter density) were included in the study. Methane was produced at a high rate in the centre of the heap at high density during the thermophilic phase of composting, and CH4 emission was only measured during this phase. In this treatment N2O was also produced in the centre both initially and after the temperature of the compost had dropped to below 45 A

Co-composting of spent pig litter and sludge with forced-aeration

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Treatment of Liquid Effluents from Dairy Cattle and Pigs using Reverse Osmosis

Posted in: Environment by admin on January 1, 1999 | No Comments

Fecal Bacteria Contamination of Surface Waters Associated with Land Application of Animal Waste

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Effectiveness of Three Manure Pit Additives

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Pit additives on the market offer solutions for the problem of odour nuisance from pig barns. They are also intended to improve manure characteristics such as handling ease, pit gas reduction, nutrient retention ans waste strength. Most of the scientific testing in this area has been completed ina laboratory or on a bench scale. To truly evaluate the effectiveness of such products in conditions duplicating most commercial barn situations, a protocol was developed. The objective of this experiment was to evaluate the effectiveness of manure pit additives in reducing odour threshold and gas concentrations above the manure surface, in reducing solids and manure strength, and maintaining nutrient and micro-nutrient content in the manure, for commercial-scale manure pits and simulated earthen manure storages.

The Harmonizing or Rural Buildings with the Landscape: Vegetation as the Tool of Integration

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Vegetation elements or screens rae one way of improving the visual quality of any rural landscape. Coming under public scrutiny, a postive looking or creative lanscape is one way of diminishing the negative impacts of intensive livestock operations. A structured landscape aroud any unit will decrease negative association with the intensive livestock unit.

Biofilter Demonstration

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The objective of this report is to demonstrate the effectiveness of biofilters to reduce odour, hydrogen sulfide and ammonia emissions from livestock facilities and manure storages using low cost biofilters with different designs, media, operating conditions and management.
The performance of twelve biofilters with different residence times (approximately 4,7 and 13 s) was measured on a dairy, swine and poultry facility. Residence times are defined as the time the air is in contact with the biofilter media.
Odour and hydrogen sulfide reduction improved from 56% to 94% as residence times increased from 4 to 7 s for the dairy and swine. Percent reduction remained about 89% as residence time increased from 7 to 13 s on the dairy and swine. A 5 s residence time is recommended for designing biofilters on swine and dairy facilities to achieve more than 80% reduction in emissions. The biofilter on the poultry facility was installed without a dust filter and dust on the fans prevented accurate airflow measurement. Reductions were less than 40% on the poultry biofilter.

Feasibility Study on the Rapid Compositional Analysis of Hog Manure by Near Infrared Spectroscopy

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This study added a near-infrared spectroscopy (NIRS) dimension to a concurrent study on long-term effects of hog manure on soil quality and productivity. It expands knowledge of the applicability of NIRS for the rapid analysis of hog manure. It complements an earlier MLMMI-supported study (98-01-15) in three ways. First, it repeated exploration of the feasibility of developing useful NIR calibrations for nutrients, N, P, and K in hog manure. Secondly, it expanded the sources of variability in the sample set from 7 to 25 hog manure ponds. Thirdly, it greatly expanded the constituents examined from physical parameters, nutrients and salts to include 27 metals and minor elements. The 75 samples in this study were analyzed by Norwest Lab for % moisture, electrical conductivity, nitrate-N, N, P, K, Na, Ca, Mg, Cl, and a suite of trace elements Because the samples were stored for several months before being scanned by NIRS, they were re-analyzed in the Freshwater Institute Analytical Laboratory for NH4-N, total dissolved N, suspended N, total dissolved P, soluble reactive P, suspended P, and suspended C. Samples were scanned using a Foss NIRSystems Inc. Model 6500 visible and near-infrared scanning spectrophotometer from 400 to 2500 nm using Near-infrared Spectroscopic Analysis Software (NSAS). Samples were scanned in a watertight cell with a path length of 2 mm in the transflectance mode. The cell was scanned in a static mode and in a spinning cup module. Calibrations were developed between the spectral data and the chemical data for each constituent using the multiple linear regression option of the NSAS software and evaluated statistically. Useful calibrations were developed for NH4-N, TDN, Suspended N, Total N, TDP, SRP, Suspended P, Total P, Suspended C, Ca, Mg, Ba, Be, Cd, Cu, Cr, Fe, Mn, Mo, Ni, Se, Sr, S, Ti, V, and Zn. Useful results were not obtained for Na, K, Cl, Al, As, B, and Li. Analysis of the constituent and spectral data by Principal Component Analysis demonstrated this may be a useful tool for sample selection for the development of future robust calibrations for field use.

Composting of sweet sorghum bagasse with other wastes

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Determining Odor Emissions from Manure Surfaces Using a Wind Tunnel

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A wind tunnel was used to measure odour emsission from the surface of a liquied manure storage basin on June 15, 1999 Nine air samples were taken from a location on the lstorage unit within a three hour period and winf speeds rnaging from 0.19 to 1.14 m/s, assessing the impact of winf speed on hydrogen sulfide emission rate. Bulk wind speed in the tunnel was calculated using the exhaust duct dimensions and air speed at the exhaust duct., Concentrations ranged from 134-588 and 57-120 ppb for odour and hydrogen sulfide respectively. Odour and hydrigen sulfide emission gernally increased with wind speed. However, it is likely the relationship between measured emission (odour and hydrogen sulfide) is dependant on factors such as roughness, adourous gas emission rate and the type of gas emitted.