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Industry Partners
Prairie Swine Centre is an affiliate of the University of Saskatchewan
Prairie Swine Centre is grateful for the assistance of the George Morris Centre in developing the economics portion of Pork Insight.
Financial support for the Enterprise Model Project and Pork Insight has been provided by:
NUTRIENT RECOVERY BY SOLID-LIQUID SEPARATION AND METHANE PRODUCTIVITY OF SOLIDS
Posted in: Environment by admin on January 1, 2007 | No Comments
Tile Water Quality following Liquid Swine Manure Application into Standing Corn
Posted in: Environment by admin on | No Comments
Environmental Friendly Waste Management Technologies
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An Alternative Arrangement of Gravel Media in Tidal Flow Reed Beds Treating Pig Farm Wastewater
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Vertical down flow and tidal flow reed beds have shown the potential of treating strong wastewaters under high organic and hydraulic loadings (Molle, Liénard, Grasmick, & Iwema, 2006; Sun, Zhao, & Allen, 2005). Gravel media in the reed beds provide filtration of suspended solids and surface areas for the attachment of biofilms to decompose soluble pollutants. Conventionally, multiple layers of gravel are arranged, to allow the sizes of gravel particles to increase progressively from the top layer to the bottom layer. However, a number of studies have reported the occurrence of clogging when reed beds with this conventional medium arrangement are operated (Blazejewski & Murat-Blazejewska, 1997; Kern & Idler, 1999; Langergraber, Haberl, Laber, & Pressl, 2003).
Clogging is considered one of the most serious operational problems occurring in both horizontal and vertical flow reed beds. When clogging occurs, the void spaces inside bed matrices are blocked, and the infiltration rate of wastewater is considerably reduced. Subsequently, the supply of oxygen into the matrices diminishes, and the treatment ability of the reed beds decreases rapidly. The mechanisms of clogging are not yet fully understood. It is generally believed that as wastewater flows through reed bed matrix suspended solids are removed by sedimentation and filtration; microorganisms then decompose the organic content of the trapped solids, while the inorganic content gradually mineralizes. Excessive growth of biofilm can also cause clogging (Austin, Maciolek, Davis, & Wallace, 2006). The growth of plant rhizomes and roots, chemical precipitation and deposition, and the formation and accumulation of humic substances may also be part of the causes. Two lab-scale reed beds (made of Perspex columns of 900 mm in height and 95 mm in diameter) were used in the study. The first bed employed conventional ‘progressively-sized’ medium arrangement; having smaller gravel size of 4±2 mm in the top layer (650 mm deep) and 26±7 mm round gravel in bottom supporting layer (150 mm deep). Having the same overall depth, the second reed bed employed an unconventional arrangement; having larger gravel size of 10±3 mm in the top layer (350 mm deep), followed by a middle layer (300 mm deep) of 4±2 mm gravel, and a bottom layer of 26±7 mm round gravel (150 mm deep). Each bed was planted with a single common reed, Phragmites australis. Results from lab-scale experiments demonstrated that in comparison with conventional progressively sized medium arrangement, employing larger gravel in the top layer of a tidal flow reed bed proved to be more effective, in terms of the removal of several major pollutants from a strong wastewater. The unconventional medium arrangement delayed the occurrence of clogging by allowing suspended solids to be deposited more uniformly inside the reed bed, and by facilitating aeration during resting period, but the arrangement did not eliminate the clogging problem. A specific clogging tendency rate was defined to provide an indication of the degree of clogging at different operation time for tidal flow reed beds. Calculation of the tendency rate revealed that the unconventional medium arrangement had a clear advantage over the conventional arrangement of employing fine gravel or sand in top layer.
Odor-Reduction Performance of Constructed Wetland Treating Diluted Swine Manure
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The objective of this study was to determine the long‐term, odor‐reduction performance of a vegetated, sub‐surface flow wetland system on a swine farm. It was found that the wetlands did treat a wide range of dilute manure ammonium and solids levels while providing significant odor reduction.
Water Requirements for Swine
Posted in: Prairie Swine Centre by admin on | No Comments
Constipated Barns: Where Has All of the Space Gone?
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Throughout North America we are experiencing a shortage of nursery and finisher space. The industry has expanded, and we have export markets to take our extra pork, but shortages of capital and environmental restrictions have limited our ability to meet the demand for new buildings. However, even well designed facilities of only a decade ago are finding themselves short on space as pigs back up in these ‘constipated’ barns. Why do we have this shortage of space? How can barns that accommodated the farm’s pigs when they were built find themselves inadequate today? There are at least three contributing factors, each of which adds to the problems created by the others. Increased sow productivity, increased days to market, and increased pig size; have all led to an increase in space needs by 13.8, 12.5 and 10.4%, respectively over the last decade. But what is the overall effect? If we were building a barn to accommodate the production of this unit how much more space would we need? The previous barn had 16 finishing rooms, each of which accommodated 253 pigs, at a floor space allowance of 0.67 m2. That resulted in 2,712 m2 of pig space in the finisher barn (excluding alleys etc.). Building today we would need 18 finishing rooms, accommodating 288 pigs, with a space allowance of 0.74 m2/pig. The total finishing pig area would be 3,836 m2. The combined effect of the three factors identified would be to increase finishing space requirements by 41.4%. Building more finishing space is an obvious means to correct the problem, but how would you do it? Adding two new rooms would address the issue of two extra weeks to market, but the existing rooms would remain overcrowded due to number of pigs and increased pig size. A change in pig flow is needed to accommodate the new standards of productivity the farm is achieving. I was recently asked to look at the plans for a new farrow-to-finish operation. Although productivity in the herd was about what I have described for our example barn, the producer had designed the barn to accommodate 30 pigs/sow/year and market weights of 140 kg. That decision will likely be best appreciated in 15 years time. Our example also shows that typical farrow-to-finish barns, with weekly finishing rooms, are not very flexible when it comes to coping with increased sow productivity or market weights. Alternative, more flexible pig flows, should be considered when setting up a new operation.