Influence of Hygrometry, Temperature and Air Flow Rate on the Evolution of Ammonia Levels

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The results of a statistical analysis would have been useful to make a better analysis of the experimental results. The ventilation extraction done under the slatted floor brings other concerns about the better ambient conditions vs. higher ammonia emissions by the air movement over manure. There is also a paradox as higher ventilation rate lowers ammonia concentrations in the ambient air inside the livestock building, it also increases the total ammonia emissions outside the building.

Covering Slurry Stores and Effects on Emissions of Ammonia and Methane

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The potential of covering the manure tanks have been confirmed and reductions of at least 90% seem to be feasible. The covers have to be sealed properly to prevent leakage and venting of the gases emitted (ammonia, H2S) could be treated trap and recycled through a scrubber. More work is needed to understand the pH changes occurring when the tank is covered as compared to uncovered as pH has an important role in ammonia release also changes in the methane measurements has also to be done as the method used was too insensitive.

Costs of New Housing Systems for Pigs with Low Ammoina Emission

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For each production stage at least 6 different techniques or systems are suggested to meet the Green Label standard which are:
for non-lactating sows 2,5 kg NH3/pig-place per year compared to traditional housing where ammonia emissions are evaluated to 4,2 kg NH3/pig-place per year;
for farrowing sows 4,0 kg NH3/pen per year compared to traditional housing where ammonia emissions are evaluated to 8,3 kg NH3/pig-place per year;
for nurseries 0,3 kg NH3/piglet-place per year compared to traditional housing where ammonia emissions are evaluated to 0,6 kg NH3/piglet-place per year;
and finishers 1,5 kg NH3/pig-place per year compared to traditional housing where ammonia emissions are evaluated to 3,0 kg NH3/pig-place per year for fully slatted floor and 2,5 for partly slatted floor.
The cheapest systems suggested are the most cost effective as they also present the lower costs per kg NH3 reduction.

Etude d'Impact du Reglement sur la Reduction de la Pollution d'Origine Agricole.

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This impact study has been prepared to present the economical, financial and environmental elements at stake with the regulation project on the reduction of pollution originating from agricultural activities. The environmental problems and setback of the control measures are presented. It is stress that environmental problems come particularly from the 3 watersheds (L’Assomption, Yamaska and Chaudiere) where the animal concentration is very high and manure production exceeds the soil baring capacity (in these areas) by 4 millions cubic meters annually which corresponds to 14,000 tons of nitrogen and 7,000 tons of phosphorus spread in excess. Discussions have been made between different organizations and individuals in order to find consensus on the different aspects of the proposed regulation. Many elements from that consultation have been approved and they are: the obligation to have manure and fertilizer management plan developed by an agronomist or by the farmer who would have received specific formation; consider the phosphorus as the limiting element in the soil where its concentration is high; minimum distances from ditches, streams, ponds or lakes for manure application; manure application period; distances for odour control. The regulation of different countries, states in the United States and also provinces in Canada are presented and some comparisons are done with Quebec’s regulation project. An economical evaluation of the impacts of such regulation is presented and the total cost associated is estimated to be 44 M$ per year. On the other hand the savings on commercial fertilizers is estimated to be from 15 to 30 M$ per year and could go as high as 60 M$/year. The nutrients losses to the streams, rivers and lakes are estimated to be reduced by 20,000 tons of nitrogen per year and 3,900 tons of phosphorus, representing 42% and 24% of the actual losses. The improvement of the water quality of many streams and river and the return for recreational use is an important advantage than has no been estimated economically.

Swine Manure: From Storage to Soil

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The Prairie Agricultural Machinery Institute (PAMI) has been involved in manure management and odour control research since 1990. Work has been realised on different stages of manure management. A layer of 6 to 10 inches unchopped dry barley straw has been found to be reduce significantly the odour emissions from earthen manure storage (EMS) and with High-Line Manufacturing (Vonda, SK) the Top Gun round bale blower has been developped to unroll the bale and blow the straw on top of liquid manure. The odour reduction is efficient for up to 6 weeks and at that time more straw can be applied. When adding a straw cover, a chopped blade has to be applied on the pump in order to chop that straw. In order to remove the soil from the buttom of the EMS, the Pitsweep has been developped and consist in a sweep auger attached to the pump inlet. The solids are then moved to the pump inlet and pumped with the liquids. The traditional agitation of the whole EMS in order to get the solids into suspension is not necessary anymore and less odours are thus produced. To transport the manure, continuous flow system (CFS) (using irrigation piping) has been compared to batch system (BS) (conventional pull type or truck mounted tanks). CFS presents some advantages with its large capacity, less field compaction and less damages done to the roads compared to BS. Work has to be done to improve the start/stop control of such systems and to improve flow control. PAMI has developped an injector with shanks spaced at 12 in. in order to deliver manure evenly and 1 1/2 in. diameter hoses to prevent clugging from straw, hair and other debris. Testing started this fall with the Green Trac injection system for manure injection into forage crop (low soil disturbance with 1/2 wide slot that are 4 1/2 in. deep. PAMI and Univ. of Saskatchewan are working on a 3 year research project in order to maximize the agronimic and environmental benefits of swine and cattle manure valorization.

Many different aspects of manure management has been investigated by PAMI and work has been done to develop new equipments for manure handling that result in less environmental impacts.

Manure Production and Characteristics – 1

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This standard give data on the characteristics of livestock manure. The chart provides information on fresh manure production and characteristics per 1000 kg live animal mass per day. Included for different animal types are total solids, density, biological and chemical oxygen demands, pH, macro and micro elements as for example: total Kjedahl nitrogen, ammonia nitrogen, total phosphorus, potassium, copper. Total coliform, fecal coliform and fecal streptococcus bacteria levels are also given.

The Effect of Reducing Excess Dietary Amino Acids on Growing-Finishing Pig Performance: An Evaluation of the Ideal Protein Concept

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The effect on the performance of reduced amino acid intake were verified on 72 gilts for the growing-finishing period. The gilts were divided in 3 groups that were fed on 3 different diets that had the same level of digestible ideal protein but not the same level of crude protein; for the growing period for 20 to 55 kg the diets contained .66% of apparent ileal digestible lysine for crude protein content of 16.6, 15.0 and 13.0% respectively and for the finishing period from 55 to 100 kg the digestible lysine content was .55% for CP of 14.2, 12.8 and 11.0% respectively. The different CP treatments did not affect the performances, daily gain, feed intake, and gain:feed for the growing and overall growing-finishing periods. However during the finishing phase the gilts fed on 11.0% CP diet showed lower daily gain and poorer gain:feed. Even if the estimated carcass lean yield was not affected by the diets, the backfat thickness tended to be greater for the gilts fed low CP diets. The results show that as long as crystalline amino acids (lysine) are added to the diets the performance of pigs wont be significantly affected for diets that are at 13% CP for the growing period and 12.8% CP for the finishing period.

Thermochemical Conversion of Livestock Manure to Produce Fuel and Reduce Odor: A Feasibility Study.

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The thermochemical conversion process (TCC) has been studied and used for coal and wood sludge application in the oil crisis of the ’70 but because of the high cost of entrants and the oil costs that decreased the research was not sustained. This process is a chemical reforming reaction where organic compounds in anaerobic conditions are heated in a pressurized enclosure. The macromolecules such as cellulose are then broken into more simple molecules of 4 to 10 carbon chains such as oils and into single carbon molecules such as methane, carbon dioxide and carbon monoxide. Manure characteristics (uniformity, energy and nutrient contents, sodium and carbon monoxide acting as catalysts in the early treatment stage), its availability, and its low cost makes it a much more desirable feed stock compared to liquidated coal and wood sludge. A preliminary study was realized to verify the TCC of livestock manure. The processing of a sample of 500 g of swine manure (20% solid and 80% water) was done in a cylinder-shape reactor at pressure varying between 13.6 and 34 bars and temperatures ranging between 250 and 490 C. This test resulted in 19.1% of the raw manure being converted into low-sulfur oils and 7.2% into methane. As TCC is a closed-loop process, a better waste management and odor control are expected. Further research is needed to optimize the operation parameters and to evaluated the economic viability of such technology applied to livestock waste.

This technology could become interesting as an alternative to fossil fuel if the technology is well controlled and adapted to livestock wastes. As long as the fuel cost stay as its present level it may be difficult to justify the technical level, complexity and costs associated to TCC.

Examining the performance of additives in reducing the odor and ammonia emissions from slurry with a standard test procedure.

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The protocol presented is dedicated to evaluation of additives in laboratory using a heated water-bath where the manure samples put in glass containers are placed. Air samples are extracted from those container for olfactometry evaluation and analysis for ammonia. The costs of common slurry additives is presented as ranging from 10 to 60 DM (6 to 35 US$) per livestock unit (500 kg live weight) per year. Ammonia reduction of 46%, 53% and 64% was obtained with rapeseed oil mix to the manure to form a top layer for addition of 20, 40 and 60 l of oil /m3 of manure.

No links are made between the results of those tests done under controlled conditions and what can happen in real scale situation.

General considerations for odor impact study

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The human nose is very sensitive and reacts rapidly to odor and also to variation in odor concentration. Odor impact studies has to consider this phenomena and the mathematical models used to evaluate odor dispersion has to be able to evaluate concentration fluctuations that occur close to the odor source because of turbulence and eddies. The eddies produce in plume fluctuations and also induce meandering. The classical Gaussian dispersion model (often used in air quality impact studies) cannot represent these phenomena by itself and has to be combine with another model to represent the meandering. The combination of the Gaussian and the Gifford model is discussed in this article.
Odor impact evaluation of a specific source is not only the results coming from a proper model. Results analysis has to be well done considering many aspects of the odor dispersion such as odor concentration and frequency of exposure and also the meteorological conditions producing such concentrations. The use of percentiles representing the percentage of time when the odor thresholds are exceeded can be a good way to represent the odor nuisance situation.

The article present well the odor impact studies however, The studies are more presented on a theoretical way with no link and validation with a real odor dispersion situation.