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915 – 401 York Avenue, Winnipeg, MB R3C 0P8 PH: (204) 945-2122 FX: (204) 945-1489 www.manure.mb.ca
Note to Reader concerning Phosphorous Redistribution Projects
In order to comply with current provincial manure management regulations, livestock producers in phosphorus surplus areas of Manitoba have to implement ways to redistribute nutrients to phosphorus deficient areas. The Manitoba Livestock Manure Management Initiative (MLMMI) is undertaking a series of projects to find effective affordable solutions for producers. This report is one of these projects.
All options available to producers in phosphorus surplus areas are under consideration. These include but are not limited to manure separation, manure handling and storage, and liquid manure transportation. This report is only one of many options that are under consideration.
ACKNOWLEDGMENT
This project was supported by the Manitoba Livestock Manure Management Initiative (MLMMI) and the Manitoba Pork Council. MLMMI is funded by the Canada and Manitoba governments through Growing
Forward 2, a federal-provincial-territorial initiative.
DISCLAIMER
Any data, analyses of data, project results and conclusions conveyed in this report are those of the project researcher and not of the government of Canada or Manitoba.
This report has been produced solely to introduce the subject matter and provide a general idea and
information for preliminary feasibility. Although the data and information used in this report was gathered
from various reliable sources, the report is based upon certain assumptions which may differ from case to
case. The report was compiled with due care and diligence, notwithstanding the contained information may
vary due to changes in any of the factors and the actual results may differ substantially from the presented
information. DGH Engineering Ltd. and its employees do not assume any liability for any financial or other
loss resulting from reliance upon this report. The information contained in the report does not preclude any
further professional advice.
Any prospective user of this report should carry out additional due diligence and gather further information
specific to the purpose of the user, including professional advice from a
qualified consultant/technical expert.
Further information or advice on how to adapt this information to one’sindividual needs can be obtained
from DGH Engineering Ltd. (contact information available at www.dghengineering.com).
EXECUTIVE SUMMARY
This project was undertaken in response to the issue of phosphorus surpluses in RMs such as La Broquerie and Hanover created by livestock manure exceeding the land base available for nutrient recycling. The economic feasibility of constructing a pipeline to transfer manure from these municipalities to a municipality further west where the nutrients can be safely utilized was investigated in this report.
A literature review was undertaken of Federal, Provincial and Municipal regulations and by-laws. The major requirements identified are the need to undertake an environmental assessment and obtain and an Environment License. In addition the pipeline legal entity would likely need to file the Manure Management Plan for the lands receiving the manure.
A review was also undertaken of the literature regarding the transportation liquid manure long distances in large diameter pipelines. It was determined that there are significant differences in reported friction losses. The literature contained some information with regard to the minimum velocity required to prevent solids settlement and plugging. A survey of local hog farmers and custom applicators transporting manure through smaller, shorter pipelines indicated that plugging is not a significant concern.
A concept design was prepared based on a hypothetical route of 35 miles in length and an annual manure volume of 60 million gallons. The concept design included a 2.0 million surge tank and a pump station at the start point. Two additional booster pumps were included at the one-third points to compensate for friction loss. Three storages, also 2.0 million gallons each, were allowed for at the end to provide surge capacity for the land application. The concept design included a 14 inch diameter HDPE pipeline that would be buried along public road allowances.
A preliminary description was provided of the corporation (or co-operative) that would be required to manage the pipeline. Critical roles would include: co-ordinating the supply of manure entering the pipeline; co-ordinating the farmers receiving the manure; filing the Manure Management Plan; and providing the manure application through custom manure applicators.
A construction budget was prepared that includes start-up costs, engineering, the environmental assessment and a public consultation process in addition to the pipeline infrastructure.
Based on the capital budget a $42 million mortgage was identified and the annual payments for 10 and 25 year paybacks were calculated. A project of this nature would likely be difficult to finance through traditional financial institutions without some type of government guarantees. The term of the loan is the single largest factor that determines the annual cost to pump a gallon of manure through the pipeline.
The unit cost to pump manure through the pipeline is 11 and 7 cents per gallon for mortgage terms of 10 and 25 years, respectively. This rate drops to 2 cents per gallon after the mortgage expires and the infrastructure has been paid for. It was estimated that the additional cost to pump manure to the pipeline from individual barns will vary from 0.5 to 1.0 cents per gallon, depending on distance. In addition, it is estimated that the cost to pump manure from the pipeline end point and inject it into the spread fields will vary from 1 to 3 cents per gallon, which rates are typically charged by custom manure applicators.
Table of Contents 1.0 Introduction ................................................................................................................................................... 1
2.0 Methodology ................................................................................................................................................. 1
3.0 Literature Review and Solicitation ............................................................................................................. 2
3.1 Regulation and By-law Review ........................................................................................................ 2
3.1.1 Permit for Manure Pipeline Installation ................................................................................. 2
3.1.2 Environment Act Licence ...................................................................................................... 3
3.1.3 RM by-laws ............................................................................................................................ 3
3.1.4 Federal Government ............................................................................................................. 3
3.2 Technical Issues ................................................................................................................................ 4
3.2.1 Rheological Properties of Manure ........................................................................................ 4
3.2.1.1 Handbook and Guide ............................................................................................................... 4
3.2.1.2 Mathematic Model for Pipeline Design.................................................................................. 5
3.2.1.3 A Farm Scale Study ................................................................................................................. 7
3.2.1.4 Solicitations ............................................................................................................................... 7
3.2.1.5 General discussion ................................................................................................................... 9
3.2.2 Measures for Preventing Plug Formation ........................................................................... 10
3.2.2.1 Minimum Velocity to Prevent Solids Settling ...................................................................... 10
3.2.2.2 Additives .................................................................................................................................. 10
3.2.2.3 Operation ................................................................................................................................. 10
3.3 Standard Specifications for Crossing Barriers .............................................................................. 10
4.0 Preliminary Design .................................................................................................................................... 11
4.1 Minimum Pumping Rate ................................................................................................................. 11
4.1.1 Manure Volume and Pumping Time ................................................................................... 11
4.1.2 Maximum Off Interval .......................................................................................................... 11
4.2 Pipe Selection .................................................................................................................................. 11
4.3 Pump Selection ............................................................................................................................... 12
5.0 Societal Issues ........................................................................................................................................... 13
6.0 Corporate and Administrative Issues...................................................................................................... 14
7.0 Cost ............................................................................................................................................................. 16
7.1 Capital Costs ................................................................................................................................... 16
7.2 Annual Cash Budget ....................................................................................................................... 17
7.3 Financing .......................................................................................................................................... 18
7.4 Other Costs ...................................................................................................................................... 18
8.0 Summary ..................................................................................................................................................... 18
References ........................................................................................................................................................ 19
Appendices
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1.0 Introduction In some intensive livestock areas, the surplus phosphorous generated from manure cannot be consumed by the crops grown in the vicinity. In most crop production areas of Manitoba chemical phosphorous fertilizer is required in addition to any manure that may be available. To transport livestock manure from surplus nutrient production areas to nutrient deficient areas is a win-win solution; if the transportation is technically and economically feasible.
This study investigated the feasibility of liquid manure transportation via pipeline in terms of legislative requirements, technical issues and economic considerations.
2.0 Methodology Manitoba Livestock Manure Management Initiative (MLMMI) designated the following conditions as the basis of this study:
a. An annual manure transportation volume of approximately 60 million gallons; b. A solids content of approximately 8% in the manure; c. Three seasonal use manure storages with a total volume of 6,000,000 gallons at the end
of the pipeline for surge capacity; and d. A hypothetical pipeline route 35 miles in length.
By the nature of pipelines, they encounter many natural and man-made obstacles. For purposes of costing out this project, it was assumed that a pipeline of this length in our province could encounter obstacles similar to the following:
To cross 2 provincial trunk highways, 2 provincial roads and approximately 30 municipal grid roads;
To cross a railway; To cross 3 waterways (one of them is very shallow); To cross an underground high voltage electrical power cable; To cross natural gas pipeline at approximately 13 points; To cross MTS buried cable at approximately 20 points, and a fibre optical cable at 2
points; To follow right-of-ways on PR’s, grid roads, and in Buffer Zones.
The legal and technical issues that the hypothetical route may encounter were investigated. Potential solutions were investigated using the following methods:
I. For legal issues, provincial regulations and Rural Municipality By-laws were reviewed.
II. For design and operation of manure pipeline transportation, a literature search was conducted for design parameters; farmers who are using pipelines to transport manure were consulted for their operational information; manure application contractors were consulted for manure transportation information with respect to pipeline/hose transportation.
III. For the technical requirements for crossing barriers, Manitoba Hydro and MTS were consulted regarding power cables, natural gas, and telephone cables. Manitoba Water
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Services Board Standard Construction Specifications was referenced. Similar legal and technical issues that DGH Engineering has experienced in previous projects were also considered. The capital costs of the pipe installation were estimated based on current market pricing. Operational costs of manure transportation were estimated based on typical depreciation rates, current fuel prices and labour rates.
3.0 Literature Review and Solicitation
To transport 60 million gallons of manure via pipeline for 35 miles is pioneering work in Manitoba; there are no precedents. The longest distance of liquid manure transportation reported in Manitoba was by tankers with a hauling distance of 64 km (40 miles) (Dick and Loewen, 2013).
3.1 Regulation and By-law Review
3.1.1 Permit for manure pipeline installation
Manure storage and disposal is regulated in Manitoba under Regulation 42/98, Livestock Manure and Mortalities Regulation, for a new or expanded livestock operation, Clause 12(1)(a) reads: "has access to additional lands suitable for the application of livestock manure located within a reasonable distance, in the director's opinion, from the new or expanded operation.‖ The "reasonable distance‖ has been interpreted as 10 miles by Manitoba Conservation and Water Stewardship (CWS). Clause 9 of Regulation 42/98 regulates manure transportation. All of the 3 sub-clauses of Clause 9 are about transporting manure in a vehicle. No permit is required for manure transportation in a vehicle. In 2009, Manitoba Conservation issued a Technical Reference Document (TRC) for Pipelines, Appurtenances and Treatment Stations. This is the only documentation that can be found specific to manure pipeline construction. Manitoba experience related to Regulation 42/98 only involves individual livestock operations that handle manure within the lands controlled (owned or leased) by the operation or under manure application agreements. The MLMMI hypothetical pipeline involves multiple livestock operations, and is probably outside the jurisdiction of Regulation 42/98. Whether the MLMMI hypothetical pipeline will be regulated by Regulation 42/98 needs to be verified with Manitoba Conservation and Water Stewardship. If it falls under Regulation 42/98, an application for a permit for the pipeline installation would need to be filed with Manitoba Conservation and Water Stewardship (CWS) Environmental Approval Branch. A permit for the construction/installation of the four seasonal use manure storages could be issued under the jurisdiction of Regulation 42/98.
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3.1.2 Environment Act Licence
Generally industrial developments are licensed under the Environmental Act. A manure transportation pipeline of the proposed scale would probably be treated as a commercial development. Regulation 164/88 (Classes of Development Regulation) Clause 3 Sub-clause 6 reads: "Pipe lines which are greater than 10 km in length‖ are classified as Class 2 developments. If the MLMMI hypothetical pipeline is a Class 2 development, an Environment Act Proposal (EAP) would need to be filed with CWS Environmental Approval Branch. The EAP will be posted on the CWS web site as well as in the Public Registry to invite public opinions on the proposed development. The EAP is circulated among approximately 20 related departments of the Federal and Provincial governments and the impacted Municipalities. Usually, concerns about public health, watercourses (pipe crossing rivers), transportation (pipe cross PR, PTH, rail) and the environment are brought toward by government agencies and the general public. The EAP involves an extensive environmental assessment. Public hearings would likely be ordered by the Minister of the Environment. The Environment License application including all of its supporting studies and activities is estimated to cost $250,000 which includes an application fee of $7,500.00. The single most contentious issue is certainly to be the risk and potential impacts of a spill. The budget presented in this study includes provisions for electronic monitoring and automatic shut-down on a sudden pressure drop. Continuous human supervision during pumping would be a minimum standard expected by the public. Since failures inevitably can happen, a detailed and well-planned emergency response plan would need to be in place to address a spill event. Liability insurance to address a spill will be a necessity and has been provided for in the budget.
3.1.3 RM by-laws
Zoning By-laws and Development Planning By-laws of the rural municipalities along the hypothetical route were reviewed. No requirements were found with potential application to manure pipeline construction.
3.1.4 Federal Government
The provincial Environmental Assessment is distributed to Federal agencies such as fisheries and Oceans who provide comments and concerns with a proposal. A Federal Environmental Assessment should not be necessary unless Federal funds are provided to the project. If required, the Federal Environmental Assessment would duplicate much of the material in the Provincial Assessment.
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3.2 Technical Issues
3.2.1 Rheological properties of manure
The friction loss of water flow in pipelines has been thoroughly studied and documented. Although many factors impact friction loss, such as viscosity, the roughness of the pipe, the shape of the pipe, etc. In a water pipeline, the friction loss is simply a function of the temperature and flow rate of the water. Almost all pipe manufacturers have friction loss charts of their products. For PVC pipe, Uni-Bell PVC Pipe Association has published a Handbook of PVC Pipe Design and Construction, in which friction loss for two standard pipes, AWWA C900 and ASTM D 2241, are provided. For comparison consistency, the US units and the metric units in the literatures were converted into imperial units in the following discussion.
3.2.1.1 Handbook and Guide
Agricultural Waste Management Field Handbook (USAD, 1996) has a table which gives the relative increase in friction loss (pressure drop) for manure slurry as compared to clean water in asphalt-dipped cast-iron pipe that is 6 to 10 inches in diameter. The handbook confirmed that this ratio was suitable for PVC pipe. Table 3–1 Friction Loss Ratio, Slurries vs. Clean Water (pipe, 6" to 10" diameter)
Velocity Solids Content
ft/s 4% 5% 6% 7% 8% 10% 1.0 1.1 1.5 2.1 2.9 4 5.3 1.5 1 1.2 1.5 2.1 2.5 4 2.0 1 1 1 1.6 1.9 3.3 3.0 1 1 1 1.3 1.6 2.9 3.5 1 1 1 1.2 1.5 2.7 4.0 1 1 1 1.1 1.3 2.5 4.5 1 1 1 1 1 2.4 5.0 1 1 1 1 1 2.3 5.5 1 1 1 1 1 2.2 6.0 1 1 1 1 1 2.1 6.5 1 1 1 1 1 2 7.0 1 1 1 1 1 2 Source: USAD (1999); original: Adapted from Colt Industries Hydraulic Handbook, Figure 44, Fairbanks Morse Pump Div., 11th Ed.
The table shows that for manure with solids content of 8% or lower, there will be no difference in friction loss between manure and water when the velocity exceeds 4.5 ft/s. This certain velocity value increases as the solids content increases.
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Roos (2013) created a Guide to Pumping Manure Slurries in Centralized Biogas Digester Systems. Roos provides curves (Figure 3-1) to describe the ratio of manure to water pressure drop in pipe. The curves are a more visual representation of the relationships in Table 3-1. In Figure 3-1, the velocity values at which friction loss for manure is the same as water are slightly higher than those shown in Table 3-1.
Figure 3-1 Friction Loss Ratio for 6” to 10” Diameter Pipe Digested Sludge (Source: Roos, 2013. Original sources: Adapted from Figure 44 of Hydraulic Handbook by Colt Industries and Table 11-1 of Agricultural Waste Management Field Handbook, U.S. Department of Agriculture, Soil Conservation Service, June 1999) For the purposes of this study the solids content is assumed to be 8%, therefore the hydraulic design of the pipeline can be the designed as a water pipeline if the manure velocity is higher than 4.5 feet per second. Assuming that 12‖ PVC DR26 (160 psi) pipe is used, the velocity of 4.5 ft/s, corresponds to a flow rate of 1,520 gallons/min, and the pressure drop is estimated to be 0.22 psi/100 ft (estimated on Reelcraft 2012 and Uni-Bell 1991). For a pipeline of 35 miles, the total pressure drop will be approximately 410 psi. Intermediate booster pumps will be needed to control operating pressures.
3.2.1.2 Mathematic Model for Pipeline Design
Bjerkholt et al. (2005) developed procedures for pipeline design for cattle manure and hog manure. The procedures were based on a study they conducted in a laboratory scale. The pipes they used were PVC with diameters of 1½‖, 2‖, 3‖ and 4‖. The length of the pipe was approximately 40 feet for each diameter. The pipelines were equipped with 14 valves. The manure used was from finisher hogs with a solids content of 4.8% for the raw manure that was diluted to 4.4%, 3.5% and 2.5%; and from dairy cattle with a solids content of 10.4% for the raw manure that was diluted to 5.5%, 5.2%, 4% and 3.5% after long fibres were removed. The flow rates used were from 30 gallons/min to 154 gallons/min (135 L/min to 700 L/min). Based on the flow rate and pipe diameters, the velocities they used in the trial can be derived as 6.4 ft/s to 17.5 ft/s in 1½‖ pipe, 3.3 ft/s to 15.5 ft/s in 2‖ pipe, and 1.6 ft/s to 7.7 ft/s in 3‖ pipe. No information was found in the report about the 4‖ pipe. The equations they created to predict the pressure drop of manure flowing in the pipe with different diameters (D) and for manure with different solids content (Ts) is shown below.
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D1.20 ∆p ───── = A (8V)s Equ 2-1 (source: Bjerkholt et al. 2005 equation 10) 4L D: pipe internal diameter in metre ∆p: differential pressure in Pa V: flow velocity in metre/second L: pipe length in metre A: coefficient A= 0.0599 Ts + 0.0288 s: coefficient s= -0.100 Ts + 1.75 Ts: solids concentration in %
Based on their equation, Figure 3-2 was developed. This Figure shows that at low velocities (below 1 ft/s), manure with higher solids content causes higher pressure drop. With increased velocity (6 ft/s for example), manure with higher solids content causes lower pressure drop. For example, at a velocity of 6 ft/s, the pressure drop caused by manure with a solids content of 6% is 0.62 psi/100 ft and for manure with a solids content of 10% is 0.34 psi/100 ft.
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The pressure drop caused by the manure with a low solids content (3% or lower) followed the pattern: the higher the solids content, the higher the pressure drop.
The mathematic model of Bjerkholt et al. (2005) did not confirm that when the velocity is above 4.5 ft/s, there are no differences in pressure drop between manure and water.
The pressure drop in the MLMMI hypothetical pipeline was predicted by Equ 2-1 to be 0.40 psi/100 ft. For a pipeline of 35 miles, the pressure drop would be approximately 739 psi.
3.2.1.3 A Farm Scale Study
Patni (1980) conducted a study on a dairy farm. In the study, the manure was pumped from a concrete manure pit under the barn floor to a remote storage approximately 2,940 feet (896 meters) away. The pipe employed in his study was HDPE with a diameter of 4‖ (100 mm). The solids contents of the manure used varied from 0.1% to 9.7%. The total pumping time was approximately 45 hours.
Figure 3-3 compares the pressure loss between dairy cattle manure and water flowing in 4‖ HDPE pipe. The data discussed here were obtained from a section of straight pipeline with a length of 1,192 feet (363.3 meters) in Patni’s (1980) trial. The straight section was chosen to eliminate the impact of joints/fittings and pipe bending.
Patni’s study showed that manure flow resulted in higher pressure drops than water flow—all of the manure points are above the water points. Patni sorted the manure into two groups: a low solids group with a solids content of 4.5% ~ 6.4%, and a high solids group with a solids content of 6.5 %~ 10.0%. He demonstrated that higher solids content produced higher pressure drops. He set linear relations between pressure drop and flow rate.
Since the linear relation was established based on flow rate, not velocity, the equations in Figure 3-3 cannot be directly used for MLMMI hypothetical pipe, which would be at a scale of 10 times or more.
Comparing the manure relationships created by Patni (2005) with the water curve, it can be predicted that there will be no difference in pressure drop between manure and water when the flow rate is high enough. For the low solids content group, this flow rate is approximately 320 gallons/min (24.3 L/s) and the corresponding velocity is approximately 8.5 ft/s. For the high solids content group, this flow rate is approximately 395 gallons/min (30 L/s) and the corresponding velocity is approximately 12.0 ft/s.
Patni’s results for the pressure drop in curved pipe and for pipe with joints/fittings are attached to this report as Appendix B.
3.2.1.4 Solicitations
Three manure application contractors were contacted for information on manure transportation in a flexible hose. A manure application contractor in the US employs flexible hose to transport 140 million US gallons (117 million Imp gallons) of manure annually. The length of the hose is up to 7 miles. For 8‖ hose, a booster pump is needed every 2 miles. The booster pressure is between 140 psi and 160 psi, the velocity is approximately 16 to 18 ft/s and the pumping rate is 2,500 US gallons/min (2,100 Imp gallons/min). For 6‖ hose, a booster pump is needed every mile. The
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working pressures of the pump are between 210 psi and 220 psi for a velocity of approximately 20 ft/s and a pumping rate of 1,800 US gallons/min (1,500 Imp gallons/min). Manure application occurs 7 months a year and pumping time is 80 hours a week.
A contractor consulted in Manitoba uses 8‖ hose to transport manure 6 miles. A booster pump is installed every 2 miles. The booster pressure is between 140 psi and 160 psi and the pumping rates are between 1,800 and 2,400 gallons/min. No plugging has ever been experienced. Another contractor in Manitoba provided similar information except the maximum transportation distance is 3 miles. The information provided by the manure application contractors corroborated each other and is listed in Table 3-2 for comparison with water. The pressure drops for manure reported by the application contractors are significantly lower than that reported for water, approximately one-half of water. The reason for this is unknown. Four farms (Farm E, Farm M, Farm R and Farm W) that use pipelines for manure transportation were consulted. Only one of them, Farm R, provided detailed information. The pipeline Farm R used was 8‖ PVC DR26 with a length of 1.85 miles. Ten cleanouts were installed along the line, approximately 900 feet apart.
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Table 3-2 Pressure Drop Comparison between Manure and Water in Hose
Hose diameter (in)
Booster distance (mile)
Booster pressure (psi)
Flow rate (gallon/min)
Velocity (ft/s)
Contractor Reported Manure Pressure drop (psi/100 ft)
Estimated Water Pressure drop from Reelcraft (psi/100 ft)*
Literature Reported Water Pressure drop from Dultmeier (psi/100 ft)+
8 2 140~160 2100 16.1 1.4 3.73 3.0 8 2 140~160 1800~ 2400
2100(ave.) 13.8~ 18.4
1.4 (ave.) 3.73 3.0
6 1 210~220 1500 20.5 4.07 8.25 7.0 *Reelcraft, 2012 Page 3. http://www.reelcraft.com/pdfs/tech_bulletins/TB0001.pdf +Dultmeier. http://www.dultmeier.com/pdfs/tech-library/02Water8.pdf There is a manure pit under the barn. The holding capacity of the pit is 400,000 gallons audit takes 8 hours to empty the pit by pumping manure via the pipeline. The working pressure is 60 psi. Based on this information, the flow rate was calculated to be 833 gallons (1,000 US gallons)/min, the manure velocity is 6.51 ft/s, and the pressure drop is 0.631 psi/100 ft. This pressure drop rate is very close to the reported pressure drop caused by water (0.649 psi/100 ft.).
3.2.1.5 General discussion
In the past half century, many studies have been conducted on the rheological properties of liquid livestock manure flowing in pipe. Manure has been tested with different solids content; from different species of livestock; and through different pipe materials. Although the reported studies provide relevant information, we have not found any design methods that are strong enough for the design of the MLMMI hypothetic pipeline. The main reason is that the studies were undertaken in small diameter pipes and/or short lengths of pipeline. Most of the studies lack farm scale conditions. The hydraulic properties of manure are more complicated than the single factor of solids content. It involves the biodegradation of the organic matter, particle size changes, biogas generation etc. Observations by DGH Engineering indicate that the viscosity of stored manure appears to be lower that of fresh slurry.
Roos (2013) noted that it was not just the solids content that affected pumping characteristics, but also the particular mix and size of materials contained in the slurry. A solids content of 8% on one day might be more difficult to pump than 10% slurry on another day at the same farm, or more difficult to pump than another 8% slurry at a farm down the road. The information obtained from the literature, Guidelines/Handbooks and local experience is inconsistent with each other and is not sufficiently reliable enough for use in the MLMMI hypothetical pipeline design. The properties for water were therefore used for the purposes of this report.
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3.2.2 Measures for preventing plug formation
3.2.2.1 Minimum velocity to prevent solids settling
Manure contains solids. If the solids settle in the pipe, a plug may be formed. It has been reported that if the manure velocity is high enough, the turbulence of flow can successfully keep the solids in suspension. Varying velocities were reported for the minimum velocity. USDA (1999) suggested a minimum velocity of 2 feet per second. NRCS-MN (2009) recommended the minimum velocity to be between 3 and 6 feet per second. Ghaffori and Flynn (2006) suggested 4.9 feet per second (1.5 m/s). Roos (2013) recommended a design velocity of 5 or 6 feet per second to keep solids entrained. The Manitoba manure application contractors reported that they never experience solids plugging while they transport manure with flexible hoses. It is noted that the velocities they employ are very high – from 14 to 20 feet per second.
3.2.2.2 Additives
There are a large number of products on the market that claim to reduce the solids in manure and improve flowability. Few of them, however, have demonstrated their effectiveness in replicated research trials (Van Devender, 2004). Two farms (Farm R and Farm M) we solicited reported they had experienced plugging caused by the solids in manure. They claimed to have solved the plug problem with additives. The long term effects of additives on the environment and crops are not fully understood. Additives are not suggested for use with the MLMMI pipeline.
3.2.2.3 Operation
All four farms consulted flush the pipeline after manure pumping. Water is pumped through the pipe for a couple of hours or the manure is blown out with air. It was reported that temporarily suspending pumping for short periods of one or two days, without flushing does not cause plugging.
3.3 Standard Specifications for Crossing Barriers
The Standard Construction Specifications (MWSB, 2013) provides details for pipelines crossing highways, railways and waterways.
PTH and PR crossing: encasement pipe is required (Appendix C-1) Railway crossing: encasement pipe is required (Appendix C-2) Waterway crossing: direction drilling is required (Appendix C-3) Rural mile road crossing: No specifications are available. RM approval is needed.
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4.0 Preliminary Design
4.1 Minimum pumping rate
There are three factors that need to be considered in determining the pumping rate. Firstly, the designated volume of manure needs to be pumped in a designated period of time. Secondly, the manure pumping needs match the manure application rate used by commercial applicators. Finally, manure pumping should be at a consistent flow to prevent sedimentation of the solids and minimize the risk of plugging.
4.1.1 Manure Volume and Pumping Time
The annual manure volume that needs to be pumped was designated as 60,000,000 gallons by MLMMI. The legal manure application period in Manitoba is between April 10 and November 10. The fall application period is from August to early November, approximately 92 calendar days consisting of 26 weekend days, 3 holidays, and 63 week days.
Table 4-1 Normal and Average Climate Data in Steinbach (1981-2010)*
Months Aug. Sept. Oct. Nov. Precipitation (mm) 73.8 57.0 45.9 28.1 Precipitation > 10 mm (days) 2.1 1.8 1.13 0.63
*Based on http://climate.weather.gc.ca/climate_normals/results_1981_2010_e.html?stnID=3675&autofwd=1 Steinbach climate data indicates that precipitation in the aforementioned three months was 176.7 mm. There are 4 days with rain/snowfall of 10 mm and more. Precipitation, mainly in the form of rain, impacts manure application and consequently impacts the manure transportation rate. It is estimated that 10 days are unsuitable for manure application and 6 of them occur on week days. Based on 57 work days and 12 hours of operation per workday, the minimum pumping rate is identified to be 1460 gallons/min, and the daily pumping volume is 1.05 million gallons. Extended work hours will provide a contingency for exceptional weather or mechanical down time.
4.1.2 Maximum off interval
The longest off interval is estimated to be 90 hours during a long weekend (Civic Day, Labour Day or Thanksgiving). It is expected that pumping can be resumed successfully after a 3 day idle period without flushing the pipeline.
4.2 Pipe selection
Two pipe materials are commonly used in manure transportation: PVC and HDPE. For the same pressure, HDPE needs a thicker pipe wall. For example, for a pressure rating of 160 psi, PVC needs DR26 and HDPE needs DR13.5. The inside diameter of 12‖ PVC (11.71‖) is similar to that of 14‖ HDPE (11.80‖). HDPE is more robust and is thermally welded to create a
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seamless pipeline. PVC has jointed sections that are solvent welded. PVC would have been significantly more expensive, therefore HDPE was chosen for this study. Cleanouts are needed every 1,000 feet and at the both sides of barrier crossings.
Static pressure of the pipeline The elevation of the start point is 230 ft higher than the end point. When the pipeline is full of manure under a zero flow conditions the internal pressure at the end point of the hypothetical route is approximately 100 psi. Friction loss The friction loss was estimated on the basis of Agricultural Waste Management Field Handbook (USAD, 1996) and A Guide to Pumping Manure Slurries in Centralized Biogas Digester Systems (Roos, 2013). The head loss caused by joints/fittings and directional changes was estimated to be 10% of the friction loss. This fraction of the friction loss is approximately equivalent to the pressure gain due to the elevation difference. Considering a flow rate of 1460 gallons/minute and a velocity of 1.5 meters/second (4.92 ft/s), the pipe diameter is chosen to be 14‖ for the HDPE pipe. The flow rate of 1460 gallons/minute is the average flow rate required. The velocity of 1.5 metres/second is the minimum velocity to keep the solids in suspension. The pressure rating of the pipe was chosen to be 165 psi to allow two booster pumps to serve the system needs.
4.3 Pump selection
Figure 4-1 shows the pipe resistance curve for the selected pump. The curve was drawn based on 14‖ HDPE pipe with a length of 11.7 miles which is one-third of the total length of 35 miles. A total of three pumps are required: one would be located at the surge tank at the start point; and the other two would be located at the one-third points to boost the pressure (from friction loss). The working point is 2,150 gallons per minute (2,580 US gallons/minute), 130 psi (300 ft.). The efficiency at the work point is 68% and the power needed is 290 HP.
Electrically driven pumps are not feasible. Manitoba Hydro expressed concerns about the large motor loads causing an unbalance of the phases on the power supply grid. In addition, the service connection costs for a relatively short term use are very expensive and compromises the economics. Diesel power was therefore chosen. The fuel consumption rate of this size engine is approximately 63 litres/hour.
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Steel tank manure storage Three surge tanks, each with a capacity of two million gallons, would be installed at the outlet end of the pipeline. In addition one surge tank was considered necessary at the inlet end to ensure consistent flow into the pipeline. The tanks include a concrete floor and internal agitation system.
5.0 Societal Issues
To establish a pipeline of this scale would require the co-operation of many individuals and organizations. Significant opposition to a project such as this should be expected. It was assumed that the pipeline would be located on public land and that privately owned land should be avoided. The support of municipal governments on whose property the pipeline must cross would be paramount. The budget presented in this study does not include any costs to purchase land or
Figure 4-1 Pump Characteristics Curve & Pipe Resistance Curve
14
pay for access rights-of-way on any lands the pipeline may cross. Such costs could be substantial, and even a few uncooperative landowners could pose significant barriers to the project. Routing the pipeline on public lands as much as possible is recommended. A public consultation program is recommended to gain public support and to minimize the impact of opponents who are normally a small minority initially but very vocal. A well-organized public consultation program includes: developing a social profile; one-on-one consultations; developing and distributing a responsive publications; holding an open houses; and holding workshops. Without a well-executed Public Consultation program, public opposition can swell and defeat the project. A budget estimate for this program is $225,000. A formal public hearing will be a part of an Environmental License application and a public consultation is an important and advantageous pre-requisite to this hearing.
6.0 Corporate and Administrative Issues
A non-profit corporation should be established to act as an administrator and legal owner of the pipeline. This corporation would be responsible for all matters related to moving manure from lagoons to crop land via the pipeline. Using a corporation to administer the pipeline limits any potential legal and financial liabilities arising from the pipeline to the corporation, and cannot be extended to its members or users. Since the corporation is not intended to be a profit-oriented enterprise, the corporation would be established as a corporation without share capital (no party owns any part of the corporation). A board would be appointed to govern the operations of the corporation. Establishing a co-operative is also possible, wherein each member would be an equal owner of the corporation. In either scenario, the corporation will need to hire a general manager to manage the pipeline. The general manager would work full-time throughout the year. We also expect that the corporation will need a skilled maintenance technician, who would be responsible for making sure the pipeline is in good working order. This technician would work full-time for six months centred around the application season and part-time for the other six months. A bookkeeper will be required to organize all financial transactions and would submit monthly financial statements to the Board of Directors for review and to use as a basis for decision-making. We expect the bookkeeper would also work full-time for six months centred around the application season and part-time for the other six months. During the application season, the corporation will need to hire an unskilled labourer to assist the maintenance technician. We expect this labourer would work full-time during the application season. The corporation will also need to contract the services of a professional accountant (a Certified General Accountant, for example) to compile the year-end financial statements, perform a financial statement review or audit (depending on if the members or an external stakeholder requires one of these), and file a Non-Profit Organization Information Return with the Canada Revenue Agency. Non-profits don’t pay income tax, but are required to file this
15
return. A conservative estimate of accounting fees would be $1,000 per year (more if a full audit is required). The cost of insurance for the pipeline would be significant, due to the possibility of manure leakage and the resultant soil and groundwater contamination. Municipalities may require comprehensive general liability insurance coverage for upwards of $2,000,000 to provide relief for spills on land not owned by the pipeline corporation. The premium for this level of coverage could be in excess of $150,000 per year. The corporation will need to budget for normal operating costs such as office rent, office supplies, travel, etc. These costs have been included in the Annual Budget provided. Hog farmers applying their manure on the fields of neighbouring landowners are responsible for completing a manure management plan. With the proposed pipeline, since the manure from many hog farms becomes blended, the pipeline corporation would likely need to assume responsibility to file a manure management plan for all the manure transported through the pipeline. This will involve extensive work co-ordinating the detailed information required to apply the manure on the fields of many receiving landowners with the manure from multiple hog operations. This work could be subcontracted to a specialist. The annual cost is estimated to be $100,000.
16
7.0 Cost
7.1 Capital Costs
Expense $ Administrative Costs: Environmental Act Proposal $250,000 Public Consultation Program $225,000 Construction Overhead and Administration* $2,612,000 Construction Quality Requirements and Testing $18,000 Construction Execution Requirements and Surveying $41,000 Engineering Fee Engineering fee $1,250,000
Route Preparation: Tree removal $24,000 Pipeline: Pipe 14‖ HDPE 35 miles $9,628,000 Pipe Installation Labour $20,379,000 Cleanouts 200 units $1,054,000 Cleanout Installation Labour $320,000 Valves 5 units $32,000 Valve Installation Labour $16,000 Cross waterway (labour inclusive) 3 sites $141,000 Cross PTH & PR (labour inclusive) 4 sites $94,000 Cross railway (labour inclusive) 1 site $24,000 Pumps 3 Pumps, including associated infrastructure 3 units $300,000 Storage Holding Storage, 1 Steel Manure Tank $658,000 Receiving Storage, 3 Steel Manure Tanks $1,974,000 Land for Manure Storages $127,000 Contingency $3,792,000 $42,959,000
Notes: * Overhead and Administration includes overhead, administration site supervision, rentals and temporary facilities The above estimate includes the cost of the land where the manure storages and pumps are to be located. Associated development costs include subdivision, approaches and granular surfacing.
17
7.2 Annual Cash Budget
Expense $
Mortgage – 25 Year Amortization $2,946,000 Mortgage – 10 Year Amortization $5,346,000 Manure Management Planning $100,000 Fuel $221,000 Repair and Maintenance $280,000 Cash Reserve $280,000 Salaries, Wages, and Benefits:
General Manager $ 100,000 Maintenance Technician $ 75,000 Bookkeeper
$ 38,000
General Labourer
$16,000 WCB/CPP/EI
$46,000
Expense Reimbursement
$5,000 Insurance Premium
$150,000
Office Rental
$12,000 Automotive Expenses
$10,000
Office & Administrative Expenses
$10,000 $1,343,000
Total Annual Cash Expenses – 25-Year Mortgage
$4,289,000 (7 cents/gallon) Total Annual Cash Expenses – 10-Year Mortgage $6,689,000 (11 cents/gallon)
Total Annual Cash Expenses – After Mortgage Payout $1,343,000 (2 cents/gallon)
Assumptions
*Mortgage: $42,000,000 at 5% interest (prime plus 2%) *Repair and maintenance were estimated as 2% of the material costs of the tankers, pumps and pipeline (approximately $12 million) *The cash reserve is an amount set aside to initially pay off the start-up costs (costs not included in the mortgage); thereafter this would build up a capital reserve to address major repairs, upgrades, modifications. *Application season runs from August to October
*General Manager works full-time throughout the year *Maintenance Technician and Bookkeeper work full-time from June-November, part-time
from December to May *General Labourer works full-time from August to October *Automotive expenses include loan/lease payments, gas, maintenance, and insurance *Office & administrative expenses include phone, internet, postage, office maintenance, accounting & legal fees, computers, office supplies, and bank charges
18
7.3 Financing
The total capital cost estimate is approximately $42,959,000. The budget presented here allows for a $42 million mortgage, therefore an initial cash injection to cover miscellaneous start-up costs including professional services will be required. These start-up costs need to be raised from interested parties, presumably the hog farms supplying manure and the landowners receiving the manure. A 25 year mortgage amortization was chosen as the maximum term as it was considered that lending institutions would consider this a high risk investment and consequently be reluctant to extend the term. A 10 year term is also presented as this is considered a worst case scenario. In reality, some level of government guarantee may be necessary to secure financing.
7.4 Other costs
This study has estimated the costs to establish a pipeline consisting of: a surge tank at the start; the pipeline, including pumps; and three surge tanks at the end. Additional costs, however, will be incurred to transfer manure from the hog barn manure storages to the start point surge tank. This would likely be undertaken by existing manure application companies and paid for directly by the individual farmer generating the manure and a budget estimate for this cost is 0.5 to 1.5 cents per gallon. Finally, the manure must be pumped from the three storage tanks at the pipeline end point and injected into the adjacent farmlands. Typical costs for this service ranges from one to three cents per gallon, depending on pumping distance. This work will be subcontracted to custom applicators and paid for by the pipeline corporation.
8.0 Summary A budget estimate was prepared to transport manure approximately 35 miles. Based on the assumptions outlined in this report, the cost to own and operate the proposed pipeline will vary from 7 to 11 cents per gallon for mortgage terms of 25 and 10 years, respectively. This cost drops to 2 cents per gallon following payment of the mortgage. The above costs only consider the cost to transport the manure from the inlet surge tanks to the outlet tanks. An additional 1.5 to 4.5 cents per gallon, however, would be required to pump manure from hog farms into the pipeline; and from the pipeline to the receiving fields. The use of a pipeline to transport manure a distance of 35 miles appears to be technically feasible, notwithstanding a manure pipeline of this scale appears to be unprecedented. The literature review conducted for this study reveals significant differences in the reported fluid dynamics of hog manure in a large diameter pipeline. Further studies are recommended as a part of the detailed design of such a pipeline to verify performance parameters such as friction loss and solids sedimentation. Public concerns regarding potential spills are likely to be significant. This could result in difficulty receiving an Environmental License. An extensive environmental assessment will be required and it is recommended that a comprehensive public consultation program be implemented to address public concerns and gain public acceptance.
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References
Bjerkholt JT, Cumby TR, Scotford IM 2005. Pipeline Design Procedures for Cattle and Pig
Slurries using a Large -scale Pipeline Apparatus, Biosystems Engineering 91 (2), 201–217
Dick, S. and Loewen, C. 2013. Understanding and Applying Real World Experiences Associated
with Separated Hog Solids Management to Manitoba. http://www.manure.mb.ca/projects/pdfs/Final%20Report%20(website)%202012-06%20Agra-Gold%20Consulting%20Separated%20hog%20solids%20management.pdf
Engineering Tool Box, http://www.engineeringtoolbox.com/pe-pipe-pressure-loss-d_619.html MWSB, 2013. Standard Construction Specifications, The Manitoba Water Services Board,
January 2013. NRCS-MN, 2009. Natural Resources Conservation Service, Conservation Practice Standard Waste Transfer No. Code 634. http://efotg.sc.egov.usda.gov/references/public/MN/634mn.pdf Patni, N. K., 1980. Pipeline Transportation of Liquid Manure, Livestock Waste: A Renewable
Resource Proceedings 4th International Symposium on Livestock Wastes 1980, Published by American Society of Agricultural Engineers, pp. 387-391.
Reelcraft 2012. Tech Bulletin Pressure Drop / Flow Rate Charts and Graphs.
http://www.reelcraft.com/pdfs/tech_bulletins/TB0001.pdf Roos, C. J., 2013. A Guide to Pumping Manure Slurries in Centralized Biogas Digester Systems.
Washington State University Extension Energy Program. Oct. 2013 revision. USDA, 1999. Agricultural Waste Management Field Handbook, U.S. Department of Agriculture,
Soil Conservation Service, July, 1999 revision, Chapter 11. ftp://ftp.wcc.nrcs.usda.gov/wntsc/AWM/handbook/ch11.pdf
Van Devender, Karl, 2004. Liquid Solids Management,
http://www.uaex.edu/publications/pdf/FSA-1041.pdf
Altitude
(feet)
Distance
(miles)
Start
Physical
Features
Crossings
Altitude
(feet)
Distance
(miles)
Physical
Features
Crossings
Altitude
(feet)
Distance
(miles)
End
Physical
Features
Crossings
0+30.5
MTS Cable
PTH
Watercourse
MB Hydro Gas
774
774
774
0+24
0+24.5
0+25
0+25.5
0+26
0+26.5
0+27
0+27.5
0+28
0+28.5
0+29
0+29.5
0+30
MTS Cable
MB Hydro Gas
Gas Pipeline
Railway
PR
781
778
778
774
774
774
0+31
0+31.5
0+32
0+32.5
0+33
0+33.5
0+34
0+34.5
0+35
0+13.5
0+14
0+14.5
0+15
804
797
MTS Cable
MB Hydro Gas
MTS Cable
Watercourse
MB Hydro Gas
797
794
794
791
787
787
784
784
781
MTS Cable
MTS Cable
MB Hydro Gas
MTS Cable
MTS Cable
MTS Cable
0+15.5
0+16
0+16.5
0+17
0+17.5
0+18
0+18.5
0+19
0+19.5
0+20
0+20.5
0+21
0+21.5
0+23.5
0+24
MTS Cable
MTS Cable
PR
MTS Optic Fibre
Watercourse
MTS Cable
MTS Cable
MTS Cable
MTS Cable
MTS Optic Fibre
MTS Cable
892
876
869
860
850
853
0+12
0+12.5
0+13
0+22
0+22.5
0+23
971
974
968
968
951
945
942
928
922
928
853
814
932
932
925
925
925
912
906
902
899
MB Hydro Gas
MB Hydro Gas
MTS Cable
MB Hydro Gas
1017
1020
1024
1004
1001
997
991
988
984
984
978
978
968
971
1020
981
997
1001
1001
1001
1001
1001
1004
1007
1010
0+10
0+10.5
0+11
0+11.5
0+12
807
MB Hydro Gas
MB Hydro Gas
0+0
0+0.5
0+1
0+1.5
0+2
0+2.5
0+3
0+3.5
0+4
0+4.5
0+5
0+5.5
0+6
0+6.5
0+7
0+7.5
0+8
0+8.5
0+9
0+9.5
MTS Cable
MB Hydro Gas
MTS Cable
MB Hydro Gas
MTS Cable
MB Hydro Gas
PTH
APPENDIX B
Panti (1980) study results
Section 1 pipe with joints and fittings
Section 2 straight pipe
Section 3 straight pipe and long bend
Appendix B Patni (1980) Study Results
APPENDIX C
C-1 Crossing PTH and PR
C-2 Crossing Railway
C-3 Crossing Waterway
