In early 2012, AOI North America received approval to replace the two coal fired boilers in the Wilson processing facility. These boilers have been in use since the plant began operation in 1974. The age and design of these boilers have created mechanical issues that continually require substantial investments to operate and maintain. At the time these boilers were built, coal and No. 6 fuel oil were the fuels of choice for industries. However, since the early 1970’s, natural gas lines have been installed in almost every area of the United States. In addition to age, the other main contributing factor in the decision to replace the boiler was the environment. Moving to natural gas is a major step in AOI’s efforts to reduce our carbon footprint and preserve our environment. Switching to natural gas will greatly reduce the emissions issues as well as eliminate the cost of storage, removal, transport, and disposal of the coal ash.
The new boilers will have a very efficient burner control and management system as well as several related systems designed to re-use the heat and water from the operation. Fuel costs should reflect a minimum of 10% savings with the efficiencies of the new boiler system along with an estimated reduction in operational and maintenance costs of approximately 80%.
The decision was made to install three 900 HP Fire Tube natural gas boilers. After much consideration we decided to dismantle the Dirt Recovery Shed and move it to a more suitable on-site location. This allowed us to put the new boiler on that site and enlarge the Dirt Recovery Shed to accommodate all three processing lines so they could be recovered individually. The building had to be dismantled, relocated, re-erected and enlarged to accomplish this. There was indeed a lot to do in a short time frame between the end of the 2013 burley season, and the beginning of the 2014 FC season; a window of only about six months.
On March 4th, removal of the equipment from the Dirt Recovery Shed began. On April 5th, the floor and foundation was poured for the new Dirt Recovery Shed, and a week later, work began to re-erect the building on its new site.
The old building was only 1600 square feet and the new Shed was enlarged to 3600 square feet to allow for separation of dirt from all three processing lines for accurate accountability. The building was finished in May, and ready for the electrical and auger installation. As the new Dirt Recovery Shed was being built,
the previous site foundation was being demolished to make room for the New Boiler House. To make the project even more difficult, the selected boiler house site was in an area where there were many underground water lines, underground fire suppression lines, underground storm sewer lines and underground sanitary sewer lines, not to mention a railroad spur and overhead power lines. All of these had to be located, documented, and more importantly, worked around.
On April 15th, we began excavating the old Dirt Recovery Shed foundation, and began site preparation for the New Boiler House. All the work had to be done before the floor was graded and formed, and any concrete was poured. On May 9th, the foundation was finished and ready for building construction to begin.
By mid-May, the first piece of the new Boiler Building was put in place. The construction went very well, with rainy weather only causing a few slight delays. The building was finished by the end of June, complete with roll-up doors, air intake fans, exhaust stack openings framed, and all water and sewer lines tied in. Work had already begun on removing the railroad spur and the installation of storm-water sewer drains. On July 23rd, the final cement was poured on the roadway between the plant and Boiler House. Setting the transformers and power panels was completed in September, and power was turned on to the building.
In retrospect, the last few months have been almost like a well-orchestrated symphony of activity, with the removal of the old Dirt Recovery Shed, the preparation for the new Dirt Recovery Shed site, the re-installation of the Dirt Recovery Shed, the site preparation of the New Boiler House, the installation of the transport augers, the electrical installation, the erecting of the New Boiler House, the digging and installation of various utilities, paving of the roadway, and the installation of the new fuel tank… not to mention the constant, and seemingly never ending discussions of permits, connections, and equipment submittals and approvals. All of this happened at the same time that a lot of people were preparing the processing plant for one of the biggest volumes in recent history, with everything coming together as scheduled. Now, we are eagerly awaiting the new boiler equipment which will begin the 2nd chapter of this project. However, this will not be the final chapter. When these boilers are commissioned and put into use in July of 2015, AOI will begin to reap the benefits of a new and modern power plant with positive results to the environment.
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