Final Report SWIne USA

Transcription

1 Final Report SWIne USA October to September Conversion, Capture and Utilization: Methane from Swine Manure Farrow to Wean Facility Completed by the Iowa Department of Natural Resources Energy and Waste Management Bureau July 2002

2 Project Overview Background In 1998, the Department of Natural Resources formed an advisory committee to support the development of a Methane Energy Recovery Program. This committee of state and federal agencies, agricultural organizations, utilities and environmental groups recognizes the increasing importance of controlling odor, reducing the risk of pollution and offsetting fossil fuel consumption. The goal of the program is to demonstrate and promote methane recovery at livestock confinements and other appropriate operations in Iowa. To meet this goal, the Department developed a methane digester demonstration and documentation project through a request for proposal process. The Department received three proposals for consideration. Proposals were reviewed by members of the Methane Energy Recovery Program Technical Subcommittee. On September 23, 1998, the full Methane Energy Recovery Program Advisory Committee unanimously recommended that Livestock U.S.A. be selected to conduct a methane energy recovery project per the requirements of the request for proposals. Livestock U.S.A. was a management entity wholly owned by Crestland Cooperative. The focus and purpose of this company was to manage the swine production system called SWIne USA, LP (now known as Bell Farms). Identification of the Parties Participants in the project included SWIne USA and Crestland Cooperative of Creston, IA, John George of Agricultural Engineering Associates of Uniontown, KS, Mark Moser and Richard Mattocks of Resource Conservation Management, Inc. of Berkeley, CA, under contract to ICF, Inc, and the AgSTAR program. Project members providing funding, oversight and technical assistance included: Iowa Department of Natural Resources, Iowa Department of Economic Development, Iowa Department of Agriculture and Land Stewardship, Natural Resource Conservation Service, Iowa State University Extension, Iowa Pork Council, National Pork Producers Council and AgSTAR. Time of Performance SWIne USA entered into a contract with the Iowa Department of Natural Resources for the development of a methane recovery system on October 1,. The contract was for the period of October 1, to September 30,. Statement of Purpose The contract between the Iowa Department of Natural Resources and SWIne USA was entered into for the construction, operation, maintenance, monitoring, evaluation, and demonstration of a methane energy recovery system at the SWIne USA, LP operation located in Union County, IA. Methane energy recovery system refers to anaerobic digestion of manure, methane capture, and energy generation and use. A feasibility study conducted in 1998 by Mr. Mark Moser, AgSTAR Technical Advisor, indicated that SWIne USA would need to utilize a methane recovery system to reduce the environmental impacts from the proposed farrow-to-wean operation on their neighbors. Odor was viewed as a major concern due to the size of the confinement. At the time of the cooperative agreement between the Department and SWIne USA, the swine producer was seeking to invest in a complete mix anaerobic digester to biologically stabilize waste, reduce pathogens, lower solids content, and control odor as well as methane production. The cost of the system would be offset by using the captured methane gas to produce electricity, reducing the farm's energy costs.

3 Scope of Work As a contractor, SWIne USA served as the Department s agent for the installation, operation, maintenance, monitoring, and demonstration of equipment and materials designed to capture methane from manure, convert methane into usable forms of energy, and use the energy produced to offset the facility's demand for electricity and propane and/or for sale to utilities or other interested parties. The contractor was required to submit monthly progress reports describing accomplishments, including documentation of all matching funds expended during the period and details of any press coverage of the project. During the monitoring phase of the project, monthly reports were required to cover at a minimum:! A summary of methane production during the month,! A summary of electricity production and heat recovery during the month,! A summary of electricity and propane use during the month,! A summary of maintenance performed and associated cost during the month,! A detailed estimate of economic benefits derived from the system during the month,! An analysis of the nutrient content of the manure processed during the month,! A summary of technology transfer and educational activities conducted during the month,! A description of any other issues that may arise as a result of the project,! Detailed documentation of matching funds expended during the month. The monitoring phase of the project turned out to be one of the most difficult scope of work items to complete. While SWIne USA did provide the majority of the required operational monitoring data, reports were often late and required extra work by the Department to obtain and analyze. SWIne USA management indicated that the required reports were often late due to the lack of qualified staff to complete the technical paperwork associated with the collection of operational data. It became clear after only a few months of digester operation that the project partners underestimated the expertise and staff hours required to complete the data gathering function. The Department did receive sufficient data to draw basic economic feasibility and cost-effectiveness conclusions. Those findings are discussed under the section on operational data. As part of the technology transfer and information dissemination requirement in the contract, the contractor was required to hold two field days at the facility to showcase the installed methane recovery and generation systems. Project Timeline 10/1/98 Project activities initiated 6/30/99 Anaerobic digester, engine generator and all related equipment installed and operational. 09/21/99 First field day 10/30/99 Broken pipe on the digester 11/1/99 Pipe fixed, system operational 01/11/00 System shut down, engine/generator problem 01/22/00 Rebuilt engine, system functioning 03/25/00 Electric motor down, system shut down 04/03/00 Repairs made, system restarted 06/03/00 Broken coupler bolts between engine and generator, system down 06/07/00 Broken bolts replaced, system is operational 08/10/00 Second field day 07/30/02 Final report

4 The project timeline was delayed throughout the contract period. A number of regulatory and construction-design problems slowed the construction of the swine facility and methane recovery system. Eventually, financial problems that were unrelated to the swine operation caused the sale of SWIne USA to Bell Farms. Following the sale, several of the personnel that were responsible for operating the digester, collecting the operational data and completing the final report left the facility for other employment. Bell Farms has continued to maintain and operate the digester and methane recovery system. Budget Summary Personnel Contract Amount Contractor Match USDA/NRCS Funding Total Project Cost Fringe Travel Equipment Supplies Contractual $100, $329, $148, $577, Other Total Cost $100, $329, $148, $577, Project Activities System Design Mark Moser, an AgSTAR technical advisor, prepared a feasibility study for the SWIne USA facility in April of A portion of the study examined the waste stream needs of a 5,000 head sow farrow to wean facility. It was determined that the facility would need to invest in a waste treatment system. Based on compliance regulations, function and cost, it was determined that a complete mix digester design was the best choice. The digester installed at SWIne USA was designed by Mark Moser of RCM Digesters, Inc. as part of the AgSTAR program. System Details The sows at the facility live in buildings with a pull plug pit manure collection. Some pits are emptied every day, with individual pits emptied every 8 to 18 days. Manure flows by gravity in pull plug gutters to a collection-pumping tank. The manure is then pumped to a heated mixed anaerobic digester. The digester tank is constructed of concrete and covered with a sealed membrane of coated fabric to retain heat and collect biogas produced by the anaerobic treatment of manure. By converting volatile solids in the manure to methane, the biogas can be captured and used to generate electricity and the effluent is rendered virtually odorless. The methane gas is fed to an internal combustion engine driving an 80 kw generator. The electricity produced is used to offset the electricity needs of the facility. Heat from the engine is captured and used to preheat the digester. Treated effluent is then drained from the digester to two concrete storage basins until the waste is ready for land application per an approved manure management plan.

5 SWIne USA Design Construction Process The construction phase of this project had many obstacles. Because methane digesters and methane recovery and generation systems are relatively new to the agricultural sector, finding an experienced contractor is often difficult. Many digester design firms are not willing to compromise patent pending technology and share complete plans with farmers and construction firms, which can complicate construction bidding and work related processes. It has been the Department's experience that cost overruns and construction delays are common with digester projects, due to a lack of information sharing between designers, contractors and facility managers. At SWIne USA, the facility manager and the contractor made several construction and planning mistakes because they lacked a complete set of design plans and access to project timelines. The contractor often received construction tasks in a piecemeal fashion, one step at a time, without knowing the "big picture." This often resulted in construction equipment and labor being sent from the contractor's home office to the facility to complete a single service, rather than completing multiple tasks during one visit. Delivery of equipment, labor and materials is often more expensive in rural areas, with additional trips adding to the cost of the project. In addition, because

6 the facility manager did not have a set of timelines to follow for the construction process, the digester tank was filled for over a month without a cover, due to an oversight in ordering equipment. This created an odor problem for the facility with daily complaints from neighbors and was expensive because the facility had to pay for propane to keep the digester tank warm. If the facility manager had access to construction timelines, the cover may have been ordered in a more timely fashion. The construction experience at SWIne USA and information obtained from similar projects across the state support the need for on-site guidance from system designers during all phases of construction. The SWIne USA manager suggested the need for the development of a generic checklist and timetable for producers going through the installation process. This would give the producer an independent source of information that could be used to monitor the progress and make sure the project is on time. At SWIne USA, construction of the swine buildings was completed and operational in February of. The digester construction began in the winter and continued until June of, when manure was first added to the digester. Regulation and Permits While animal confinement operations with anaerobic digesters and methane recovery systems require many of the same state and county permits as any other confinement facilities operating in the state, facilities with digesters and methane recovery systems that apply for permits may face special challenges. State and local officials are often not familiar with digester and methane recovery technology. This could lead to construction delays and increased cost for those who are seeking to build systems. In the case of adding a system to an existing operation, some of the manure basins may be grandfathered into compliance, but the addition of any new digester and methane recovery equipment would require the old basins to meet the current code. During the permitting process for SWIne USA, the management of the facility was critical of the Department process for obtaining the necessary construction permits. Complaints included taking too long to issue a final permit, failing to communicate effectively with the contractor and construction firm on-site and requiring a construction process that was not cost-effective. The Department has begun working with stakeholders to streamline the permit process. The goal is to provide a complete package approach to agricultural producers seeking to install a digester and methane recovery system. The package would provide a clear outline of the steps necessary to obtain construction and operational permits, including relevant contact information at the state and local level. Electric Utility Interconnection SWIne USA negotiated an interconnection and generation agreement with Clarke Rural Electric Cooperative. This agreement allows SWIne USA to generate electricity using an engine generator that runs on biogas. The electricity is either consumed on-site or sent back into the local power grid, with the producer receiving a guaranteed price. The agreement between SWIne and Clarke Rural Electric outlines the per kwh value of the excess electricity generated from biogas at the facility, safety requirements and operational responsibilities. Demonstration and Dissemination Activities An educational field day was held at the site on September 21,. There were 130 registrants at the event and an additional 20 walk-ins. Participants were divided into four groups and shuttled between four informational stations. The presentations included the following: Storage and utilization of swine manure, Paul Miller, NRCS, Des Moines, IA

7 Methane recovery system design and function, Mark Moser, Resource Conservation Management, Inc., Berkeley, CA Electrical cogeneration and generator design function, John George, Agricultural Engineering Associates, Uniontown, KS Working together in electrical generation and utilization, and environmental benefits of methane recovery in swine production, Tom Kilabrew and Don Reasoner, Osceola, IA, and Alison Kovac, Iowa Department of Natural Resources, Des Moines, IA After lunch, Larry Crosser, General Manager, Crestland Cooperative spoke on the role of the cooperative in the changing pork industry. The station presenters formed a panel and answered questions from the audience. The field day proved to be successful and informative for the participants. The second educational field day was held on August 10,. David Downing and Lee Vannoy represented the Department during the visit. Gary Weeda, Manager of SWIne USA and his staff answered technical questions and people attending the open house were allowed to tour the facility. The digester and generator were operational, providing energy to the facility. Lee Vannoy commented on a number of changes at the facility since the last open house, including the reinforcement of the digester walls and changes in the generator exhaust. Project Economic Feasibility and Cost-Effectiveness System Design Cost Engineering and design work was estimated at $31,000. Cost of Construction The feasibility study estimated the total cost of the digester and methane recovery system, including engineering and design, would be approximately $336,000. However, the total construction cost for the digester and methane recovery system at SWIne USA was approximately $500,000, or $100 per sow. The difference between the estimated cost of construction and the actual cost incurred can be attributed to several factors. First, it is common for construction costs to run as much as 10 percent above preconstruction estimates. Both owners and general contractors often hire the firms they trust and are familiar with, not the lowest bid. Second, construction costs in rural areas vary greatly, particularly for material costs, such as lumber and concrete. Also, if contractors have to travel great distances to perform repeated tasks, costs for services escalate. This is particularly true for heavy equipment functions. Finally, a large factor in cost overruns for the SWIne USA facility was inefficient use of equipment and labor due to the lack of information and technology transfer between the contractor and the design team. Without having a design team member on-site during the construction phase of the project, contractors made several mistakes that cost time and money. The facility manager and contractors rarely had a set of complete plans to work from and were given construction assignments without being able to see the complete picture. These limitations hindered the contractor in providing construction advice and increased the overall cost of the project. Operational Data Operational Activities from September to September Biogas produced 99,569 Cubic feet x 100 metered Methane produced* 71,869 Cubic feet x 100 (estimated) Electricity produced 435,848 kwh metered

8 Engine heat recovered 2,849 Btu recovered (x10 6 ) Electricity purchased 713,120 kwh $0.066 kwh Propane purchased -0- gallons $0.56/gallon *Biogas is estimated to be 72% methane, based on average CO 2 reading of 28%. Monthly Summary of Operational Data (September September ) September October November December January February March Biogas produced (Cu. Ft.) Methane (est. 70%-75%) (Cu. Ft.) Electricity produced (kwh) Engine heat recovered (BTU x 10 6 ) Electricity purchased (kwh) Propane purchased (Gallons) 877, , , , , , , , , , , , , ,302 30,591 34,229 42,815 48,232 21,145 43,845 41, ,120 73,520 56,000 58,320 89,680 65,280 72, Biogas produced (Cu. Ft.) Methane (est. 70%-75%) (Cu. Ft.) Electricity produced (kwh) Engine heat recovered (BTU x 10 6 ) Electricity purchased (kwh) Propane purchased (Gallons) April 900,900 May 1,004,50 0 June July August September 727, , , , , , , , , ,208 41,712 45,078 31,696 30,734 13,385 10, ,760 44,560 55,600 71,280 na na Maintenance Performed The oil was changed in the cogeneration engine every 250 hours, with an average material cost of $75. The daily operation and maintenance time was figured at 1.5 hours per day with a cost of $18/hour. Actual maintenance tasks

9 On September 30,, an elbow slipped off a pipe in the digester and allowed manure to flow out of the digester and into a tile that drained into a county road ditch. A county road crew working on a culvert nearby was able to contain the manure in the ditch, preventing it from flowing into the Grand River. The contained manure was diluted with water and pumped back into a concrete storage tank. The pipe was fixed and steps taken to close the inlet to the tile line to prevent this type of leak in the future. On January 11,, the engine/generator was shut down due to an engine malfunction. The automatic shut off did not work in this situation, allowing the engine to overheat. The engine was down for eleven days and required reconstruction. The engine/generator was brought back on line on January 22,. On March 25,, an electric motor, needed to keep the system in series, went down and needed to be replaced. Due to errors in shipping, the motor took a week to receive. The engine was down for 8 days and was restarted on April 3,. On June 3,, the engine generator was shut down due to broken bolts in the coupler from the engine to the generator. Special bolts were needed and took several days to receive and fix. The engine was restarted on June 7,. Over the first year of operation, the digester functioned very well, while most of the downtime was due to engine-generator maintenance. Engine Efficiency Below is a graph of average engine fuel consumption per kilowatt-hour of energy produced for each month of operation. The engine efficiency is holding close to 14,000 Btu/kWh as shown below. Since March, there has been a slight trend towards higher fuel consumption. More data is needed to determine if this is a trend or just another aberration in the data. Swine USA - Engine Efficiency 20,000 18,000 16,000 14,000 BTU/Kwh 12,000 10,000 8,000 6,000 4,000 2,000 - Sep-99 Oct-99 Nov-99 Dec-99 Jan-00 Feb-00 Mar-00 Apr-00 May-00 Jun-00 Economic Benefits

10 Based on the economic data provided below, the average monthly return is $1,083. With the total cost of the digester and methane recovery system at $500,000, a simple payback is estimated to be 38 years. Savings and Expenditures from September to July Savings Electricity generated $27, Propane purchased $-0- Total $27, Expenditures Materials $3, Labor $10, Total $14, Net Annual Savings $12, Monthly Summary of Economic Benefits (September September ) Savings per month: Electricity (kwh x $0.066) Expenditures per month: September October November December January February March $2, $2, $2, $3, $1, $2, $2, Materials $ $ $ $ $ $ $ Labor $ $ $ $ $2, $ $ Total $1, $1, $1, $1, $2, $1, $1, Net (savingsexpenditure) Number of oil changes + $ $1, $1, $1, $ $1, $1, April May June July August September Savings per month: Electricity (kwh x $0.066) Expenditures per month: $2, $2, $2, $2, $ $ Materials $ $ $ $ na na Labor $ $ $ $ Total $1, $ $1, $1, Net (savingsexpenditure) +$1, $1, $ $859.68

11 Number of oil changes Odor Control While it is difficult to place a monetary value on odor control, it is clear in the case of SWIne USA and other concentrated animal confinement operations that the ability to reduce odor levels can be the difference between operating the facility or closing the doors. The feasibility study determined that a digester and methane recovery system would be a necessity to control odor if SWIne USA was to be constructed at the selected site. This was due to size of the facility, location of neighbors and the heated political climate regarding odor issues. At SWIne USA, manure odors were tested by Dr. Dwaine Bundy, using pit additive columns at Iowa State University. Manure odor levels were taken from digested and undigested manure samples. The test concluded that manure that had been digested properly had much lower hydrogen sulfide and odor threshold levels than manure that was undigested. Visitors to SWIne USA will notice lower odor levels when compared to most open lagoon systems found at other confinement operations. Lessons Learned Construction and operation managers need to have complete design plans before initial land grading and facility construction begins. This will ensure grading will be done to proper elevations and size. A designated point person on-site is needed to organize and oversee project, keep construction on schedule, keep funds allocated and track costs. If designer has proprietary information, the designer needs to be on site and in charge of construction, oversee the construction and work with the contractor. If the people with proprietary information cannot be on site or do not want to oversee the construction, the designer needs to supply complete design plans and information to the contractor and construction manager. One of the most important tasks involved in the installation of a methane recovery and generation system is obtaining an interconnection and generation agreement from the local utility. The generation agreement should be one of the first steps following the design process, before any construction begins, in order to avoid unnecessary delays in electrical generation start-up.

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