SEPARATION OF WASH/SPILLAGE WATER FROM DEFECATED MANURE

SEPARATION OF WASH/SPILLAGE WATER FROM DEFECATED MANURE Final Report Submitted to Manitoba Livestock Manure Management Initiative Inc. By DGH Engineering Ltd. March, 2002

Acknowledgements DGH Engineering Ltd. would like to express its gratitude to Manitoba Livestock Manure Management Initiative Inc. (MLMMI) as well as the Agri-Food Research & Development Initiative (ARDI) for the financial support and co-operation provided during the course of this study. Additionally, DGH Engineering Ltd. would like to thank Clearwater Colony Farm for allowing use of and access to their hog barn and ongoing co-operation and assistance throughout the study. The advice and co-operation of Dr. Q. Zhang, University of Manitoba is also gratefully acknowledged.

Executive Summary A technology to separate defecated manure and urine from spillage water in hog farrowing barns has been developed in the Netherlands to reduce ammonia emissions up to 50 to 65 percent. A project was undertaken at a local Manitoba farm to evaluate the potential for this technology to reduce odour emitted from a farrowing barn. A test room with ten sows had the manure pit divided into a defecated manure (manure) channel and a spillage water (water) channel. The manure channel comprised approximately 33 percent of the total pit area. There was 1.3 m 2 of manure surface area per sow. A control room with 28 sows was used for comparative purposes. All comparative data was analyzed on a per sow or a unit ventilation rate basis. The total nitrogen, ammonia, ph, electrical conductivity, phosphorous, potassium, sulphur, and total solids in the manure channel were significantly higher than the water channel. The values of these parameters were approximately two to 15 times higher in the manure channel than the water channel. The odour emission rate in terms of per sow from the test room was approximately 17 percent lower than the control room. The mean emission rate from the test room was 60.6 OU*m 3 /sow/s, while the control room was 73.4 OU*m 3 /sow/s. The hydrogen sulfide emission rate from the test room (0.92 L/sow/day) was approximately 27 percent lower than the control room (1.26 L/sow/day). The ammonia emission rate from the test room was approximately 25 percent lower than the control room. The mean ammonia emission rates were 19.8 and 26.3 L/sow/day from the test room and control room, respectively. Since odour is emitted from sources other than the manure surface, the reduced impact on the odour emission rate as compared to hydrogen sulfide and ammonia is to be expected. Hydrogen sulfide and ammonia can be emitted only from the manure surface, while odour is emitted from sources other than open manure, diluting the effect of manure surface treatments. The test room released approximately 1.5 kg less nitrogen per sow per year than the control room. The separated spillage water, up to six cubic metres per sow per year, is suitable for use as flush water in other rooms in the barn, which would result in a significant reduction in water consumption and wastewater production. The total potential saving due to nitrogen retention and reduced water consumption is approximately $13.00 per sow place per year. The cost of an imported gutter from the Netherlands is $375.00, however this cost should be reduced substantially if they were to be manufactured in Manitoba. Practical applications of the research results to existing building systems are discussed for farrowing, dry sow, weanling and grower/finisher production areas.

1.0 INTRODUCTION Odour is a concern to neighbors of hog barns. Hog barn odours emanate from the surfaces of floors, walls and pens; as well as from manure collection, storage and spreading; feed storage; dead storage and disposal; and from the hogs themselves. Ammonia (NH 3 ) and hydrogen sulfide (H 2 S) are two major odorous gases emitted from animal operations (Xue and Chen, 1999). These gases are generated while manure undergoes microbial degradation. Ammonia is produced by the decomposition of nitrogen-containing compounds in the excreta, especially in urine. Hydrogen sulfide is typically the result of the anaerobic decomposition of sulfur-containing amino acids in a dung/urine mixture (Overcash et al., 1983). To reduce odour, intensive research has been undertaken on the emissions from manure storage and application. The result has been new technologies such as synthetic manure storage covers and methods of injecting manure directly into the soil, which can reduce the odour level dramatically during manure storage and application. Technologies to reduce barn odour, however, have not been readily available. A concept to modify manure collection pits has been developed in the Netherlands. The idea is to confine the majority of the feces and urine in a customized gutter that minimizes the surface of this strongest portion of the total wastes. This approach can be implemented to maximum effect in a farrowing room where all the feces and urine from the sow can be collected beneath as little as 15 to 20 percent of the pen area. Similar but less dramatic reductions in the surface area of the highest strength wastes could be achieved in other areas of modern swine facilities. Some gutter manufactures in the Netherlands claim that their products can reduce ammonia emission up to 65 percent (IC-W, 2001). The potential for separation to control odour is based on the principal that manure odour release is a mass transfer process occurring at the liquid-air interface. When passing over the free surface of a liquid, air tends to sweep away any gases and vapors emitted from the liquid phase. Miner (1973) and Card (1998) believed that mass transfer coefficients could be used to characterize the transfer rate of a gas through an interfacial boundary layer. The emission rate of a compound from an aqueous phase into gas phase is defined by R v = K t (C l - C g /H c ) A (1-1) Where R v = mass transfer rate K t = overall mass transfer rate C l = liquid-phase concentration C g = gas-phase concentration H c = henry s law coefficient A = surface area The emission rate is a function the surface area of the gas/liquid interface and the concentration of the compound in the liquid and gas phases. Reducing the surface area - 1 -

potentially slows down the emission rate and eventually reduces the total amount of the compound emission during a certain period of time. Since manure slurry is not an ideal solution, the real emission model of this odorous material would be much more complex than expressed in the Eq. 1-1. 2.0 OBJECTIVES The objective of this study was to determine the effect that the separation of spillage water from defecated manure has on the reduction of odour, ammonia and hydrogen sulfide emissions from swine barns. The nitrogen conservation effect resulting from ammonia emissions was to be evaluated. As well the extent to which the reuse of spilled water could reduce water consumption was to be estimated. 3.0 MATERIALS AND METHODS 3.1 Site Description The study took place on Clearwater Colony Farm located in the Rural Municipality of Rockwood, Manitoba. The farm provided two farrow rooms for this study. One of the rooms was used as a test room to demonstrate the effect of waste separation, while the other was used as a control room. The test room had an area of 887 square feet, with a holding capacity of 10 sows. A concrete divider was constructed in the manure pit to divide the pit into two channels: a spillage water (water) channel and a defecated manure (manure) channel. The surface areas of the water and manure channels were 280 and 140 square feet respectively. The test room was equipped with a 24 inch exhaust fan. The characteristics of these rooms are outlined in Appendix A. The area of the control room was 2045 square feet with a holding capacity of 28 sows. There were two identical pits (east pit and west pit) in the control room. The surface area of a single pit was 630 square feet. The room was equipped with two 24 inch exhaust fans (west and east). The west fan was in operation for the full duration of the study (April to October), while the east fan ran periodically from June to September according to the variation of the ventilation demand. A farrow cycles in farrow room starts with filling the entire room with predeliver sows. The sows stay and deliver in the room. The sows and their offspring are held in the room for an average of 20 days after farrowing. The rooms are emptied all on the same day at the end of the farrow cycle. The room is then soaked, pressure washed, disinfected and allowed to dry before refilling with the next batch of sows. At the beginning of a farrow cycle, the discharge hole of the manure pit was plugged. The pit is filled with two to four inches of water. During the farrow cycle, manure and urine and spillage water are stored in the pit. The manure pit was emptied and washed after the room is emptied. There was no drainage before the room was emptied. The liquid samples were collected immediately after the rooms were emptied and before the pressure washing. - 2 -

3.2 Sampling and Laboratory Testing 3.2.1 Liquid testing A period of two months was allowed to acclimatize the newly installed divided pit system. Liquid samples were then collected from the pits in the control room, and the water and manure channels in the test room. These samples were collected following the end of four successive farrow-lactation cycles in each room. The initial sample set was submitted to Enviro-Test Laboratories in Winnipeg, Manitoba, to evaluate total solids (TS), total Kjeldahl nitrogen (TKN), ammonia, electrical conductivity (EC), sodium, potassium, sulfur and ph. The subsequent three sample sets were only tested for TKN and ammonia. The measurement of TKN provided the basis from which to determine the effect that pit separation had on nitrogen conservation. The TKN concentration multiplied by the volume of liquid in the pit yields the total nitrogen in the room during one farrow-lactation cycle. This value was to be used to estimate nitrogen accumulation per sow per day. 3.2.2 Air sampling for odour testing Originally, odour sampling was scheduled to occur on the same day that liquid sampling was conducted. In practice, however, it was found that this schedule was not practical, as weather conditions and laboratory scheduling were problematic. On days with strong winds, which can greatly influence sample quality, sampling had to be postponed. As well, the odour samples had to be analyzed within 24 hours of collection. In some cases, laboratory analysis could not be scheduled for the sampling day. As a result, odour sampling was conducted on a different day than liquid sampling. The air samples for odour testing were collected both inside and outside of the barn rooms. The samples from inside the rooms were collected around the pits approximately four inches below the slatted floor. The exterior samples were collected at the exhaust fan s outlet. The air flow rates were measured while air sampling took place. The samples were collected with Tedlar bags and an AC SCENT Vacuum Chamber. An air sampling was completed in two steps: filling the bag for conditioning and collecting a sample for testing. In the first step, a Tedlar bag was placed in AC SCENT Vacuum Chamber. The bag was filled with air sample ¼ to ½ full and then was evacuated. This first step is also known as coating the bag. The actual sample collection was completed in the second step. In this step the bag was filled ¾ full. The air samples were sent to the University of Manitoba where they were tested within 24 hours of their collection. In the laboratory, samples were analyzed for odour with a dynamic olfactometer. In order to observe hydrogen sulfide concentration change in the storage period (from sampling to testing), hydrogen sulfide concentration was also tested in the lab at the beginning of this study. 3.2.3 Hydrogen sulfide field measurement Hydrogen sulfide (H 2 S) concentration was also measured in the field using a Jerome 631-X Hydrogen Sulfide Analyzer that provided a range of measurement spanning from 0.003 parts per million (ppm) to 50 ppm. The hydrogen sulfide concentration, in ppm, was displayed on a digital meter following the measurement cycle. - 3 -

The hydrogen sulfide concentrations were measured at the outlet of the exhaust fans in conjunction with the measurement of air flow rate through the fans. 3.2.4 Ammonia field measurement Ammonia (NH 3 ) concentration was measured with a Dräger Gas Detector providing a standard range of measurement varying from 5 ppm to 70 ppm. Dräger 5/a ammonia tubes were used. The standard number of stokes of the Dräger gas detector pump is 10. In this study, however, the number of stokes were adjusted according to the ammonia concentration to minimize the relative error caused by diffusion of the discoloration scale. The ammonia measurement was always conducted at the same time and location as the hydrogen sulfide measurement. 3.2.5 Ventilation rate measurement To evaluate the odour, hydrogen sulfide and ammonia emission rates, the ventilation rates were measured while sampling was conducted. The instrument employed for ventilation measurement was an ALNOR Electronic Balometer, with an APM 150 Meter, capable of measurements from 50 to 2000 CFM (24 to 940 L/s). The meter is able to show the instantaneous flow rate on the digital screen, store several readings during the sampling period, and give the average flow rate for the period. 3.2.6 Odour, ammonia and hydrogen sulfide emission rate calculation The unit emission rate of the tested criteria was calculated as: Volume Concentration of the criteria X Air Flowrate Unit emission rate = (2-1) Number of sows in barn The effect of manure channel separation on emission reduction can be observed by comparing the unit emission rates between the test room and the control room. 3.2.7 Environmental Controls The operating environments in the control and test rooms were monitored by members of Clearwater Colony Farm in an effort to maintain as much similarity between the two rooms as possible. The items monitored included temperature, humidity, water consumption, feed consumption as well as fill and empty dates. The monitoring data is attached in Appendix B. 4.0 RESULTS AND DISCUSSION 4.1 Results of Liquid Sample Analysis The concrete divider that provided the separation of wash/spillage water from defecated manure, had a substantial effect on the total solids (TS), total sulfur (S), total potassium - 4 -

(K), total sodium (Na), electrical conductivity (EC), ph level, ammonia and total Kjeldahl nitrogen (TKN) concentrations. The test results are listed in Table 1. The separated manure was approximately 2.6 to 15.9 times more concentrated than the separated wash/spillage water. Among them, the ratios in ionized matters, such as EC (closely related to total dissolved solids), Na, and K, 2.6, 3.0 and 5.2 respectively, were smaller than in the other matters which from 8.0 to 15.9. The reason causing this is not clear, however, the sodium chloride in the feed spilled in water channel definitely contribute to the increase of Na concentration and affect the Na ratio of manure channel to water channel. The separated manure was approximately 1.6 to 2.1 times more concentrated than the control sample for all criteria except sodium. Figure 1 provides a graphical representation of the data in Table 1. ph values are not represented in the figure, as separation has a minimal effect on ph. EC is presented in Figure 1 in terms of Total Dissolved Solids (TDS), since the EC of liquid waste is based on the TDS change (Metcalf and Eddy, 1991). Table 1 Characteristics of the liquid samples from water channel and manure channel in the test room and from manure pits in the control room Samples ph TKN (mg/l) NH 3 (mg/l) EC (ms/cm) Na (mg/l) P (mg/l) K (mg/l) S (mg/l) TS (mg/l) separated water 500 300 6.7 5 99 186 204 43 9000 separated manure 4000 2700 7.3 13 298 2960 1070 497 86000 control sample 2500 1600 7.1 8 301 1480 615 260 41000 Manure/water 800% 900% 260% 301% 1591% 525% 1156% 956% Water/control 20% 19% 63% 33% 13% 33% 17% 22% Manure/control 160% 169% 163% 99% 200% 174% 191% 210% Ratio Table 1 indicates that a certain amount of the impurities in the water channel can be attributed to the feces and urine production from the piglets, as well as spilled feed. Sodium and potassium concentrations proved to be affected less by the separation technique, than were other the test criteria. 4.2 Odour, Hydrogen Sulfide and Ammonia in the Barn Rooms The odour samples obtained inside the barn were collected at three points along each of the water channel and manure channel in the test room and six points around the manure pits in the control room, approximately four inches below the slatted floor. Hydrogen sulfide concentration and ammonia concentration were each measured 12 times. A significant difference in odour levels above the manure pits was observed between the control room and the test room. The mean odour levels were 2705 odour units (OU) with a standard deviation (SD) of 574 in the control room and 1627 OU with a SD of 461 in the test room. The mean odour concentration measured above the test pit was 40% less than that above the control pit. Figure 2 shows the odour levels of the individual samples. - 5 -

Figure 1: Comparison of Chemical Characteristics of Liquid Samples from Control Room Manure Pits and Test Room Manure Channel and Water Channel Figure 2: Odour Concentration in Air Immediately Above Manure Pits - 6 -

No significant difference in odour levels was detected between the samples collected above the water and manure channels. The mean odour levels were 1603 with a SD of 663 in the water channel and 1650 with a SD of 298 OU in the manure channel (Table 2). This was not expected as it was predicted that the odour concentration above the water would be less than that above the concentrated manure. A possible explanation for this phenomenon is that the concrete pit divider has little to no effect on the containment of odour. Thus, odorous molecules are free to flow over the divider from the more concentrated manure to the less concentrated water channel and elevate the odour concentration. At the same time, the air molecules flow from the water channel to the manure channel and dilute the odour concentration above the manure. Odour concentration and airflow caused by ventilation are the two driving forces behind this odour equalization. As a result, the difference in odour concentrations between the water and manure channels was very limited. Table 2 Odour Levels in Test Room Manure Pit (OU) Sample position Door side Middle Fan side Mean SD (north) (south) Water channel 1986 837 1986 1603 663 Manure channel 1980 1574 1397 1650 299 Theoretically, when the odour molecule equilibrium point is reached, the odour concentration on the manure side should be somewhat higher than that on the water side, because odour is continuously released from the manure. However, this difference in odour concentration was not significant enough to be identified by human olfactormeter panelists. Twelve hydrogen sulfide measurements were conducted in each room, with six from each of the water and manure channels in the test room, and six from each pit in the control room. The results of hydrogen sulfide measurement show that the average H 2 S concentration in the control room was 2.3 times higher than that in the test room (Table 3 & Figure 3). Table 3 H 2 S concentration in the air above the pits Sample position Sampled at from 13:30 to 14:45 Sampled from 16:20 to 17:40 Average Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sample 6 test manure channel 1.5 1.7 1.7 1.04 1.1 0.91 1.325 room water channel 1.1 0.99 1.3 0.52 0.62 0.71 0.873 control east pit 2.9 2.8 2.1 2.5 2.4 1.9 2.433 room west pit 2.1 2.8 2.5 2.6 2.0 2.2 2.367 Table 3 also shows that hydrogen sulfide concentrations were lower directly above the water channel than directly above the manure channel. This difference was more readily identified than the odour tests because of the JEROME meter is more sensitive than human odour panelists. In addition, H 2 S is dense molecule and likely diffuses more slowly than other constituents of odour increasing the gradient immediately above the emitting surface. - 7 -

Figure 3: Hydrogen Sulfide Concentration in Air Immediately Above Manure Pits Figure 4: Ammonia Concentration in Air Immediately Above Manure Pits - 8 -

The ammonia concentrations in the test and control room were compared as shown in Table 4 and Figure 4. Table 4 Ammonia concentration in the air above the pits (ppm) Control room Test room Sampling time Sample ID control room east test room west pit test room manure test room water channel pit channel 13:00-14:45 Sample 1 15 10 5 4 13:00-14:45 Sample 2 6 11 3 5 13:00-14:45 Sample 3 10 10 3 2 16:20-17:40 Sample 4 10 8 2 2 16:20-17:40 Sample 5 12 16 7 2 16:20-17:40 Sample 6 11 12 3 3 Average 10.7 11.2 3.8 3.0 The comparison of the criteria in the rooms only partially reflects the effectiveness of the water and manure separation. Since the test room and the control room used in this study have different sizes and different holding capacities, it is necessary to investigate the emission rates of odour, hydrogen sulfide and ammonia from the rooms. 4.3 Odour, Hydrogen Sulfide and Ammonia Emission Rates Figure 5 compares the odour emission rate from the test and control rooms as measured in the discharge ventilation air. The average emission rates from the test and control rooms were 60.6 with a SD of 35.8 and 73.4 with a SD of 37.0 OU*m 3 per sow per second, respectively. The average odour emission rate from the test room was approximate 17 percent lower than the control room. The overall hydrogen sulfide emission rate from the test room was 0.92 with a SD of 0.04 litres per sow per day, approximately 27 percent lower than the control room with a value of 1.26 with a SD of 0.17 litres per sow per day. Comparing 14 samples collected from the test room exhaust fan and 22 samples collected from the control room exhaust fans, the ammonia emission rate from the test room was approximately 25 percent lower than the control room. This ammonia reduction is lower than the 50 to 65 percent reduction obtained in the Netherlands. In the systems used in the Netherlands, the defecated manure surface for one sow is reported as low as 0.8 m 2 (8.6 ft 2 ) and the water channel comprises 80 percent of the pit surface. In this study, the geometry of the installation was limited by the need to retrofit the system to an existing barn. The water channel occupied 67 percent of the pit area and each sow had 1.3 m 2 (14 ft 2 ) manure channel. The ammonia average emission rates were observed as 19.8 L/sow/day with a SD of 2.20 from the test room and 26.3 L/sow/day with a SD of 2.95 from the control room in terms of litre per sow per day. The equivalent emission rates were 5.5 and 7.3 kg ammonia (4.5 and 5.9 kg nitrogen) per sow per year from the test or the control room, respectively. - 9 -

Figure 5: Odour Emission Rate Comparison - 10 -

Figure 6: Hydrogen Sulphide Emission Rate Comparison - 11 -

Figure 7: Ammonia Emission Rate Comparison - 12 -

The reduction in hydrogen sulfide emission rate is very close to the reduction in ammonia emission. The reduction in odour emission rate is lower than the reduction in either H 2 S and NH 3. Hydrogen sulfide and ammonia can only come from manure, but odour may result from other sources besides manure. 4.4 Nitrogen Conservation Nitrogen levels were determined in both liquid and air samples in an effort to demonstrate the effect separation had on nitrogen conservation. This analysis, however, was clouded by some questionable laboratory test results with respect to TKN and ammonia. The laboratory reports indicated that two of the four manure samples had ammonia concentrations in excess of the TKN concentration. This data is assumed to be incorrect as ammonia is a component of TKN, and therefore cannot exceed the TKN levels. Based on previous studies, the percentage of ammonia to TKN in manure pits should be approximately 60 to 70 percent (DGH, 2001). The Farm Practice Guidelines (Manitoba Agriculture, 1998) also reported that the typical ratio is 67 percent, and range of ratios is from 40 to 78 percent. The ammonia to TKN ratio indicates the degree of mineralization of organic nitrogen in the manure. The average retention time of the manure in the collection pits was approximately 10 to 15 days. The organic nitrogen could not be thoroughly mineralized during this period. Based on the difficulties mentioned above in the nitrogen analysis of the liquid samples, the nitrogen conservation was estimated from the difference in ammonia emission rate between the control and the test room. 5.0 COST/BENEFIT ESTIMATION Besides the environmental benefit of odour emission reduction, some economic benefit is also provided by utilizing the separation technique. The associated nitrogen conservation provided by the reduction in ammonia emission adds to the fertilizer value of the manure. As well the manure volume can be reduced by using the spillage water for flushing other barn rooms. These savings have been estimated below: Nitrogen in the manure is conserved lowering ammonia emission. The difference in annual ammonia emission between the control room (7.3 kg/sow/year) and the test room (5.5 kg/sow/year) is 1.8 kg ammonia (1.5kg nitrogen)/sow/year. To purchase the same amount of fertilizer would cost $1.15 ($0.77/kg N). The spillage water is calculated as 6 m 3 /sow/year. Assuming that 4 m 3 /sow/year of fresh water can be saved if the spillage is employed for other barn flushing, the total manure volume will be reduced by 4 m 3 /sow/year. The saving in manure application and transportation will be approximately $11.71/sow/year. The manure transportation cost has been estimated on the basis of a tanker hauling two miles: The unit cost was based on the first mile $1.21/m 3 ($0.0055/gallon), second mile $0.22/m 3 ($0.001/gallon) (Royal service, 2000). The cost of manure application has been estimated on $1.496/m 3 ($0.0068/gallon) (Manitoba Agriculture, 1998). Currently, no gutter manufacture exists in Manitoba. The costs of importing a gutter from the Netherlands will be expensive (US$250/sow). However, if the separation technology - 13 -

was adopted in Manitoba, local manufacturers would fabricate these gutters and the cost could be reduced. 6.0 CONCLUSIONS 1. Odour levels detected in the two farrow rooms monitored in this study were much higher compared to the odour emission levels reported by Zhang et al. (2000). 2. The concrete divider provided substantial separation in TKN, NH 3, TS, S and P in the test room. The values of these parameters were approximately 8 to 15 times higher in the manure channel than in the water channel. The concentrations of Na and K in the manure channel were 2 and 5 times higher than in the water channel. 3. The ammonia emission rate from the test room was approximately 25 percent lower than that from the control room. The mean emission rates were 19.8 and 26.3 L/sow/day from the test room and from the control room respectively. 4. The hydrogen sulfide emission rate from the test room was 27 percent lower than the control room. The mean emission rates were 0.92 and 1.26 L/sow/day from the test room and from the control room respectively. 5. The odour emission rate from the test room was approximately 17 percent lower than that from the control room. The mean emission rates were 60.6 and 73.4 OU m 3 /sow/s from the test room and from the control room respectively. 6. The nitrogen conservation obtained was 1.5 kg N/sow/year. 7. Approximately six cubic metres of spillage water can be collected in one sow place per year. A potential benefit of separation is to reuse this spillage water as flush water in other rooms in the barn, which will result in a reduction in water consumption and slurry production. 7.0 APPLICATION OF FINDINGS Practical application of the results can be made to building design in several areas, as outlined below. Segregation of the manure gutter from water spillage areas can be implemented in farrowing barns immediately, as was undertaken in this study. A practice that is followed in the design of many dry sow facilities to gain some small economies in construction is the combining of walkway and manure gutter areas, as shown in Figure 8. This practice should be curtailed, since the results of this study clearly confirm that increasing the surface area of the high-strength wastes increases NH 3 and odour emissions. A large proportion of finisher facilities have been designed using totally slotted floors. Although pens are totally slotted, pigs still choose areas for dunging and do not use all areas uniformly. However, it has become common practice to open cross-over channels between the various manure gutters to allow equalization of manure accumulation. - 14 -

Although this seems to simplify manure handling, the results of this study would suggest that this practice is most likely to increase odour emissions significantly. Alternate manure gutter strategies need to be explored. Similarly, with weaned pig housing systems where total slats have been utilized exclusively for several years, little regard has been given to the development of specific dunging areas. Also, a common design of manure gutters for these types of facilities has paid no regard to the potential to separate high strength wastes from other areas. It may be possible to develop pen and manure pit systems that recognize the separation between sleeping and dunging areas. Most certainly and immediately, subdividing pits into sections that can capture high strength wastes from the most common dunging areas separately will reduce NH 3 and odour emissions. - 15 -

Figure 8: Typical extended pit under alley in dry sow area Modified pit design in dry sow area to reduce odour and gas emissions Floor Slats Manure Pit Figure 8-A Typical Extended pit under alley in dry sow area Manure Pit Manure Pit Solid Alley Floor Figure 8-B Modified Pit Design in Dry Sow Area to Reduce Odour and Gas Emissions - 16 -

REFERENCES Card, Thomas R., 1998. Fundamentals: Chemistry and Characteristics of Odors and VOCs, Chapter 2 in Odor and VOC Control Handbook, McGraw-Hill, 1998. DGH, 2001. DGH Engineering Ltd., The Effect of Earthen Manure Storage Covers on Nutrient Conservation and Stabilisation of Manure, Final report submitted to MLMMI. IC-W, 2001, IC-W Mestpan, www.intercontinental.nl. MB, 1998. Manitoba Agriculture, The Agricultural Guidelines Development Committee, Farm Practices Guidelines for Hog Producers in Manitoba. Miner, J. R. 1973. Odour from Livestock Production. 1973. Corvallis, Ore.: Agricultural Engineering Dept., Oregon State University. Overcash, M. R., F. J. Humenik, and J. R. Miner. 1983. Livestock Waste Management, Vol. II. Boca Raton, Fla.: CRP Press, Inc. Xue, S. K., and Chen, S., 1999, Surface Oxidation for Reducing Ammonia and Hydrogen Sulfide Emissions from Dairy Manure Storage, Transactions of ASAE, Vol. 42, No. 5, 1401-1408. Zhang, Q., G. Plohman, and J. Zhou. 2000. Measurement of Odour Emissions from Hog Operations in Manitoba, Final Report Submitted to MLMMI. - 17 -

Appendix A Site and Operation Information Information about test room and control room Operation logs during study period

Control Room Dimension: 89 X 23 Manure collection pit: 2 X 84 X 7-6 Exhausts: 2 X 24 fans Holding capacity: 28 sows Basic Information of the Barn Rooms Test Room Dimension: 65 X 13-6 Manure collection pit: 1 X 60 X 7-6 Divider: 30 ft 2, Water channel: 280 ft 2, Manure channel: 140 ft 2 Exhausts: 1 X 24 fans Holding capacity: 10 sows East East Pit East Fan Control Room West Pit West Fan North South Manure Channel Water Channel Test Room Fan Fan West

Barn: Control Room Date Number of Pigs Temperature Humidity Notes Sows Piglets (ºC) (%) (Time) 13-May 28 100 23.00 40 9:00 16-May 28 100 25.00 41 17:00 17-May 28 180 24.00 58 8:30 18-May 28 180 26.00 29 15:00 19-May 28 252 24.00 36 9:00 21-May 28 252 23.00 43 9:00 25-May 28 252 24.00 59 9:00 26-May 28 252 24.00 61 11:00 29-May 28 252 23.00 47 9:00 01-Jun 28 252 21.00 63 10:00 02-Jun 28 23.00 53 16:00 03-Jun 28 250 21.00 59 9:00 05-Jun 28 250 21.00 51 9:00 06-Jun 28 250 20.00 65 9:00 08-Jun 28 244 21.00 70 9:00 Water Metre Waste Depth Time Date Reading M 3 East Pit West Pit Feed East West (inch) (inch) a) 13-May 20.5 25.5 6 6 b) 8-Jun 28.3 34.3 11 12 22254.3 kg c) total d) water feed 29.43 per sow a) = Before fill with pigs b) = After emptying c) = Before discharge d) = After water filling

Barn: Control Room Date Number of Pigs Temperature Humidity Notes Sows Piglets (ºC) (%) (Time) 26-Jun 28 254 26.75 28-Jun 28 252 22.00 40 30-Jun 28 252 22.50 36 01-Jul 28 252 25.00 36 15:00 02-Jul 28 252 23.00 57 9:00 03-Jul 28 252 23.00 67 8:00 04-Jul 28 252 23.00 57 9:00 05-Jul 28 251 23.00 54 9:00 06-Jul 28 251 25.00 70 12:00 08-Jul 28 251 24.00 68 8:00 09-Jul 28 251 26.00 67 9:00 10-Jul 28 251 24.00 67 9:00 12-Jul 28 244 23.00 67 9:00 Water Metre Waste Depth Time Date Reading M 3 East Pit West Pit East West (inch) (inch) a) 26-Jun 34 93 7.75 9.5 b) 8-Jul 42 57 14 16.75 c) d) Feed a) = Before fill with pigs b) = After emptying c) = Before discharge d) = After water filling

Barn: Control Room Date Number of Pigs Temperature Humidity Notes Sows Piglets (ºC) (%) (Time) 27-Jul 28 280 24.00 Zero feed 7/27 5100 28-Jul 28 280 24.00 31-Jul 28 280 24.00 01- Aug 28 280 26.00 02- Aug 28 280 27.00 04- Aug 28 280 28.00 10:00 05- Aug 28 280 28.00 11:00 07- Aug 28 280 29.00 15:00 08- Aug 28 280 29.00 15:00 10- Aug 28 280 22.00 9:00 11- Aug 28 280 28.00 15:00 15- Aug 28 250 23.00 20:00 Water Metre Waste Depth Time Date Reading M 3 East Pit West Pit East West (inch) (inch) a) 27-Jul 53.8 73.7 7.75 8.75 b) 16-Aug 71.6 93.0 14.75 13.5 c) d) Feed a) = Before fill with pigs b) = After emptying c) = Before discharge d) = After water filling

Barn: Control Room Date Number of Pigs Temperature Humidity Notes Sows Piglets (ºC) (%) (Time) 03-Sep 28 280 23.75 zero feed 9/3 9:00 04-Sep 28 280 29.75 17:00 05-Sep 28 280 24.00 9:00 06-Sep 28 280 24.50 10:00 10-Sep 28 270 25.50 14:00 13-Sep 28 270 22.00 11:00 15-Sep 28 270 22.25 10:00 20-Sep 28 252 22.00 9:00 Water Metre Waste Depth Time Date Reading M 3 East Pit West Pit Feed East West (inch) (inch) a) 03-Sep 79.8 100.4 8.75 7.25 Zero feed 9/3 b) 20-Sep 91.05 110.05 15 13.75 c) d) Dry M 2401.3 kg a) = Before fill with pigs Total feed 29515 kg b) = After emptying c) = Before discharge d) = After water filling

Barn: Test Room Date Number of Pigs Temperature Humidity Notes Sows Piglets (ºC) (%) (Time) 12-Mar 9 23.00 47 16-Mar 9 24.00 35 17-Mar 9 25 25.00 33 18-Mar 8 77 23.50 39 20-Mar 7 47 23.75 50 15:00 23-Mar 10 80 23.50 42 9:30 24-Mar 10 83 22.50 30 14:00 25-Mar 10 83 23.00 30 14:00 26-Mar 10 83 23.00 30 9:00 27-Mar 10 83 22.75 36 9:00 30-Mar 10 83 23.00 50 9:00 02-Apr 10 83 22.00 64 13:00 03Apr 10 83 22.00 40 12:00 04-Apr 10 83 22.50 39 14:00 06-Apr 10 83 22.75 39 9:30 07-Apr 10 83 23.25 38 9:30 09-Apr 10 83 23.50 40 9:30 10-Apr 10 83 21.50 44 9:30 Water Metre Waste Depth Time Date Reading M 3 East Pit West Pit East West (inch) (inch) a) 12-Mar 0 3.5 5 b) 10-Apr 4.7 7.2 7.2 c) 11-Apr d) Feed a) = Before fill with pigs b) = After emptying c) = Before discharge d) = After water filling

Barn: Test Room Date Number of Pigs Temperature Humidity Notes Sows Piglets (ºC) (%) (Time) 08-May 10 81 21.60 54 13:00 11-May 10 81 22.00 55 9:00 12-May 10 80 21.70 56 10:00 16-May 10 80 24.00 38 14:00 18-May 10 80 20.00 49 9:00 19-May 10 80 24.00 43 15:00 21-May 10 80 23.00 44 9:00 24-May 9 70 23.00 58 16:00 25-May 9 70 22.00 50 9:30 26-May 9 70 23:00 63 11:00 29-May 9 70 23.00 60 9:00 Water Metre Waste Depth Time Date Reading M 3 East Pit West Pit East West (inch) (inch) a) 08-May 8.9 5.25 5.25 b) 29-May 13.6 7.5 9.5 c) d) Feed a) = Before fill with pigs b) = After emptying c) = Before discharge d) = After water filling

Barn: Test Room Date Number of Pigs Temperature Humidity Notes Sows Piglets (ºC) (%) (Time) 08-Jun 10 26.00 57 13:00 09-Jun 10 92 22.00 62 9:00 10-Jun 10 92 27.00 37 15:00 11-Jun 10 92 23.00 65 9:00 12-Jun 10 92 23.00 52 17:00 14-Jun 10 92 22.00 66 17:00 16-Jun 10 92 20.00 54 9:00 18-Jun 10 92 22.00 56 9:00 20-Jun 10 92 23.00 59 9:00 21-Jun 10 92 23.00 61 9:00 22-Jun 10 86 24.00 52 13:00 22-Jun 10 86 24.00 64 9:00 24-Jun 10 86 26.00 67 13:00 26-Jun 10 86 24.00 62 11:00 28-Jun 10 86 24.00 75 15:00 Water Metre Waste Depth Time Date Reading M 3 East Pit West Pit Feed East West (inch) (inch) a) 08-Jun 15.5 4.5 5.25 Zero 6/8/01 b) 28-Jun 20 8.5 9.5 10.455 kg feed and water c) Consumed with feeding system d) 115 kg dry matter consumed a) = Before fill with pigs b) = After emptying c) = Before discharge d) = After water filling

Barn: Test Room Date Number of Pigs Temperature Humidity Notes Sows Piglets (ºC) (%) (Time) 05-Aug 10 90 24.00 8:00 06-Aug 10 50 27.00 11:00 08-Aug 10 90 27.00 16:00 10-Aug 10 90 22.00 9:00 11-Aug 10 90 26.00 15:00 29-Aug 10 75 23.00 10:00 Water Metre Waste Depth Time Date Reading M 3 East Pit West Pit Feed East West (inch) (inch) a) 05-Aug 31.4 7 7 Zero Aug 5 8:00 b) 29-Aug 41.6 9 15 Zero Aug 29 c) d) 11820 kg feed water a) = Before fill with pigs 1038.2 kg Dry matter b) = After emptying c) = Before discharge d) = After water filling

Appendix B Laboratory Results Sampling Events and Farrowing Cycles Results of Odour, Hydrogen Sulfide and Ammonia Test Results of Liquid Test Methodology of Odour Test

May 29 Sampling at exhausts (Only west fan of the control room in operation) Room Samples Flowrate m 3 /h DT/OU H 2 S (ppm) NH 3 (ppm) Control 28 Sows Test 10 Sows 5 west fan-1 2560 1172 0.625 13.2 5 west fan-2 2488 1484 0.735 14.0 5 west fan-3 2480 1641 0.625 12.1 5 west fan-4 2472 1660 0.865 12.4 5 west fan-5 2392 1484 0.665 13.4 5 west fan-6 2208 816 0.675 10.8 6-1 1327 1035 0.315 6.2 6-2 1298 567 0.240 6.3 6-3 1345 452 0.200 7.5 6-4 1433 642 0.385 6.7 6-5 1524 567 0.265 5.9 6-6 1572 286 0.150 5.3 August 10 Sampling at exhausts Room Samples Flowrate m 3 /h DT/OU H 2 S (ppm) NH 3 (ppm) Control 28 Sows Test 10 Sows 5 west fan-1 1790 3875 0.41 11.2 5 west fan-2 1893 2391 0.39 10.2 5 west fan-3 2002 2113 0.56 9.7 5 west fan-4 1864 2394 0.45 10.9 5 east fan-1 1299 3458 0.46 11.5 5 east fan-2 1345 2706 0.46 10.6 5 east fan-3 1260 648 0.38 11.7 5 east fan-4 1227 2700 0.41 10.7 6-1 1320 642 0.15 6.7 6-2 1266 2402 0.46 6.1 6-3 1207 1875 0.27 7.0 6-4 1333 2391 0.33 7.2

September 19 Sampling at exhausts Room Samples Flowrate m 3 /h DT/OU H 2 S (ppm) NH 3 (ppm) Control 28 Sows Test 10 Sows 5 west fan-1 1344 3095 11.1 5 west fan-2 1359 2425 9.8 5 west fan-3 1230 6531 10.6 5 west fan-4 1211 4938 11.3 5 east fan-1 1342 4259 10.6 5 east fan-2 1233 5951 10.2 5 east fan-3 1370 3095 9.4 5 east fan-4 1334 3095 10.5 6-1 1320 2711 5.8 6-2 1209 3730 5.2 6-3 1217 2711 6.2 6-4 1305 1654 5.6 September 20 Sampling at exhausts Room Samples Flowrate m 3 /h DT/OU H 2 S (ppm) NH 3 (ppm) Control 28 Sows Test 10 Sows 5 west fan-1 1998 0.38 5 west fan-2 1903 0.39 5 west fan-3 2158 0.37 5 west fan-4 2000 0.45 5 west fan-5 2315 0.33 5 west fan-6 2219 0.31 5 east fan-1 1299 0.46 5 east fan-2 1345 0.45 5 east fan-3 1476 0.38 5 east fan-4 1321 0.41 5 east fan-5 1478 0.35 5 east fan-6 1341 0.33 6-1 965 0.46 6-2 1477 0.30 6-3 1207 0.37 6-4 1333 0.27 6-5 1337 0.32 6-6 1199 0.24

October 18 Odour levels in barn rooms (DT/OU) ID Control Room Test Room East Pit West Pit Manure Water Sample 1 2230 2223 1980 1986 Sample 2 2230 2819 1575 837 Sample 3 3565 3165 1397 1986 October 18 Hydrogen sulfide concentration in barn rooms (ppm) Time ID Control Room Test Room Hallway East Pit West Pit Manure Water Hallway 13:00-14:45 Sample 1 2.9 2.1 2.3 1.5 1.1 1.1 13:00-14:45 Sample 2 2.8 2.8 1.8 1.7 0.99 1.3 13:00-14:45 Sample 3 2.1 2.5 2.1 1.7 1.3 1.2 16:20-17:40 Sample 4 2.5 2.6 1.04 0.52 16:20-17:40 Sample 5 2.4 2.0 1.1 0.62 16:20-17:40 Sample 6 1.9 2.2 0.91 0.71 October 18 Ammonia Concentration in barn rooms (ppm) Time ID Control Room Test Room East Pit West Pit Manure Water Sample 1 15 10 5 4 13:00-14:45 Sample 2 6 11 3 5 13:00-14:45 Sample 3 10 10 3 2 16:20-17:40 Sample 4 10 8 2 2 16:20-17:40 Sample 5 12 16 7 2 16:20-17:40 Sample 6 11 12 3 3

Control Room Liquid Sample Analysis (Lab: Enviro-Test Laboratories) Sample Date: June 7 Sampling Point Ammonia Analysis TKN Analysis Remarks west and east (mg/l) Date (mg/l) Date ph, EC, Na, K, S and total pits, mixed 2200 June 18 3400 June 18 solids were reported. Sampling Point EC Total Na Total P Total K Total S Total ph west and east (ms/cm) (mg/l) (mg/l) (mg/l) (mg/l) Solids % pits, mixed 6.7 11 273 2740 799 430 6.3 Sample Date: July 12 Sampling Point Ammonia Analysis TKN Analysis Remarks west and east (mg/l) Date (mg/l) Date ph, EC, Na, K, S and total pits, mixed 1600 July 20 2500 July 20 solids were reported. Sampling Point EC Total Na Total P Total K Total S Total ph west and east (ms/cm) (mg/l) (mg/l) (mg/l) (mg/l) Solids % pits, mixed 7.1 8 301 1480 615 260 4.1 Sample Date: August 16 Sampling Point Ammonia Analysis TKN Analysis Remarks west and east (mg/l) Date (mg/l) Date ph, EC, Na, K, S and total pits, mixed 1300 Aug 23 1900 July 20 solids were reported. Sampling Point EC Total Na Total P Total K Total S Total ph west and east (ms/cm) (mg/l) (mg/l) (mg/l) (mg/l) Solids % pits, mixed 7.1 7 79 1780 501 222 3.7 Sample Date: September 20 Ammonia Sampling Point (mg/l) Analysis Date TKN (mg/l) Analysis Date east pit 2100 Sept 27 3900 Oct 19 west pit 1700 Sept 27 4500 Oct 19 Remarks TKN was tested one month later after Sampling. PH and EC were reported Sampling Point ph Analysis Date EC (ms/cm) Analysis Date east pit 7.3 Sept 27 8.3 Sept 27 west pit 7.5 Sept 27 8.8 Sept 27

Sample Date: May 29 Ammonia Sampling Point (mg/l) TEST ROOM liquid sample analysis (Lab: Enviro-Test Laboratories) Analysis Date TKN (mg/l) Analysis Date water channel 326 June 12 426 June 16 Remarks manure channel 3390 June 5 3160 June 5 Ammonia is higher than TKN Sample Date: June 28 Ammonia Sampling Point (mg/l) Analysis Date TKN (mg/l) Analysis Date water channel 300 July 5 500 July 5 manure channel 2700 July 5 4000 July 5 Remarks PH, EC, Na, P, K, S, and total solids were reported. Sampling Point ph EC (ms/cm) Total Na (mg/l) Total P (mg/l) Total K (mg/l) Total S (mg/l) Total Solids % water channel 6.7 5 99 186 204 43 0.9 manure channel 7.3 13 298 2960 1070 497 8.6 Sample Date: July 30 Ammonia Sampling Point (mg/l) Analysis Date TKN (mg/l) Analysis Date water channel 192 Aug 14 411 Aug 8 manure channel 1990 Aug 14 2260 Aug 8 Remarks Sample Date: Aug 31 Ammonia Sampling Point (mg/l) Analysis Date TKN (mg/l) Analysis Date Remarks water channel 220 Sept 21 219 Sept 6 Ammonia is higher thantkn. manure channel 1650 Sept 21 1580 Sept 6 Ammonia is higher than TKN

Methodology of Odour Test In this study, odour level test was conducted by the University of Manitoba. The following information is provided by the Biosystems Engineering Department of the University of Manitoba. Odour evaluation A dynamic-dilution olfactometer (AC SCENT, St. Croix Sensory, Inc., Stillwater, MN) and six screened assessors were used to determine the odour concentration (level) of each sample. The olfactometer was capable of providing 14 dilution levels, with dilution ratios between 8 to 66667. The odour concentration measured by the olfactometer was expressed as the dilution-to-detection threshold (DT), or odour unit (OU), which represented the number of dilutions needed to bring the odour down to the level that could be detected by 50% of the population. Odour evaluations were conducted in the Sensory Laboratory of the Canadian Food Inspection Agency, Winnipeg. The room that housed the olfactometer had a positive ventilation system with carbon-filtered air to eliminate background odours. For each sensory session, flow rates of the olfactometer were calibrated before and after testing and the average of the two calibrations were used in calculating dilution ratios. The triangular forcedchoice method was used to present samples to the assessors, with a 3-s sniff time (St. Croix Sensory, 1999). Panel data were retrospectively screened to remove outliners by comparing assessors individual threshold estimates with the panel average. The retrospective screening was based on the following criterion (St. Croix Sensory, 1999): D ITE /DT D ITE DT D= (1) - DT/D ITE D ITE DT where D = deviation of individual threshold estimate from panel average D ITE = individual threshold estimate DT = panel average detection threshold Any assessor with a D greater than 5.0 or lower than 5.0 was eliminated from the test results (CEN, 1999). Selection of odour assessors The assessors (panelists) were selected through a two-level sequential screening procedure. At both levels, each participant was presented with three flasks of n-butanol solution or water, one of which was different in odour intensity from the other two. Participants were asked to choose the odd sample (triangle test). In each testing session, participants were presented with six sets of three flasks. For each participant, the number of correct choices was plotted against the number of triangle tests (Meilgaard et al., 1991). This would place the participant in one of three regions: reject, continue testing or accept. For those who fell in the category of continue testing, the tests were repeated on subsequent days until they moved into the accept or reject region. Those participants who moved into the accept region during the first level screening would begin the second level of screening. Participants who were eventually moved to the accept region of the second level screening were selected as assessors. Meilgaard, M. 1991. Sensory evaluation techniques, 2 nd ed. Boca Raton: CRC Press. St. Croix Sensory, 1999. User Manual of Olfactometer. St. Croix Sensory Inc., Stillwater, MN.

Appendix C Photographs

Examples of two segregated manure pits used in The Netherlands, similar to those used in this study