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Arkansas Company Automates Dry Kilns
Anthony Timberlands uses Lignomat control system to improve lumber quality
By Tim Cox
Date Posted: 7/2/2004
Anthony Timberlands Inc. received positive feedback from its customers when it updated its drying operations with Lignomat kiln control systems.
Anthony Timberlands is a family-owned company that has been in business almost 100 years. It is led by chairman John Ed Anthony, president Steve Anthony and executive vice president Rick Green. The company has substantial hardwood and softwood forest land holdings centered in south Arkansas.
Mike McQueen, vice president for hardwood operations, supervises hardwood production and sales at the company’s mill in Beirne, which is about 85 miles southwest of Little Rock and 60 miles northeast of Texarkana, Tex.
In addition the hardwood mill in Beirne, the company has two pine sawmills in Arkansas — in Malvern, which is about 48 miles northeast of Beirne, and Bearden, which is about 55 miles southeast. The pine mills, which cut more than 240 million board feet annually combined, produce 5/4 radius decking, dimension lumber and export grade Southern yellow pine. Most of the company’s pine production is sold to large treaters, distribution centers and ‘big box’ home improvement stores.
Anthony Timberlands also is in the treated lumber business; it has a facility in Hope, located about 30 miles southwest of Beirne, that treated 70 million board feet last year.
The company’s hardwood mill produces mainly 4/4 lumber — red oak and white oak and a small volume of ash. The sawmill’s 125 employees are projected to produce close to 50 million board feet this year. The mill’s production is sold kiln-dried except for pallet cants. The company’s principal market is the flooring industry with other markets in moulding, cabinets, Surface Four Sided lumber, furniture and pallets.
Incoming logs are either sawn immediately or put underwater to prevent them from drying, stain and other defects. The Beirne sawmill takes logs to an 8-inch top and a 35-inch butt. There are two log processing lines in the mill. A Filer & Stowell 7-foot band mill is used for primary breakdown of big grade logs and rough, crooked logs. It is equipped with a USNR carriage and USNR optimization technology. Resawing is accomplished on a Salem horizontal resaw.
The other production line cuts the average size logs and relies on a Salem quad band mill. Maxi-Mill supplied the overhead carriage, scanning optimization and controls for the quad system. This breakdown line has a shifting saw section USNR Schurman gang saw equipped with USNR optimization.
The company is in the midst of installing a Hi-Tech optimized edger that will replace two conventional edgers. In the past year it also installed a Hi-Tech optimized trimmer, three 300 hp boilers that are fired by wood waste, and a Hemco automated sorting system that is now being updated with Hi-Tech controls.
Anthony Timberlands also is the process of building new dry kilns that will give it combined capacity of 1.4 million board feet. In addition, it has pre-drier capacity of 1.75 million board feet.
The company has been adding or replacing dry kilns with Unitemp Dry Kilns since 1997, and with the addition of the three new dry kilns supplied by Unitemp Dry Kilns, it will have 14 in all. The company also plans in the future to tear down four masonry track kilns fired by natural gas and replace them with more Unitemp kilns.
In addition, within the past year Anthony Timberlands began updating its dry kilns with Lignomat kiln control systems, and the Lignomat systems are being installed on its new kilns. Anthony Timberlands began using its first Lignomat kiln control system in January.
When asked about the company’s experience with Lignomat controls, Mike first turned the conversation to Jackie Overton, the long-time kiln operator for Anthony Timberlands. “We have had a very good kiln operator,” said Mike. Jackie was among the first people in the forest products industry to receive training to be designated a master kiln operator. He used conventional methods to monitor and control the company’s dry kilns for years.
The Lignomat kiln control system provides a number of important benefits to Anthony Timberlands. Perhaps most important for Jackie, the system is automated. “It has made his job much easier now,” said Mike.
Lignomat supplies probes, measuring devices and computer software to monitor and control drying operations. The Lignomat kiln control system features wireless communication technology, so there is no need to ‘hard wire’ anything inside the kiln, Mike noted. The software program and other technology allows the company to set parameters for the drying operations, and the Lignomat kiln control system monitors kiln temperature, humidity, and lumber moisture content, automatically controlling kiln functions according to the inputted parameters.
The primary reason that Anthony Timberlands went to Lignomat controls was to improve lumber quality, said Mike. The objectives have been achieved. “Every one (of our customers) has noticed a difference in the quality,” said Mike.
The Lignomat kiln control system also has benefited the company by reducing drying time although that was not a goal. The drying process has been speeded up by 15%, Mike estimated, which also has reduced energy costs.
For example, the company usually increases the kiln temperature when lumber moisture is reduced to preset levels. A charge of lumber may reach that point late at night, however; with a kiln that is manually monitored and operated, a half-day or more would be lost before the kiln operator adjusted the temperature the following morning. “The computer is on 24-7,” observed Mike. As drying progresses and reaches the point where temperature or venting is changed, those processes are controlled automatically. The system controls separate schedules for warm-up, equalization and conditioning.
Green oak lumber coming off the saw has moisture as high as 70%, Mike noted. The lumber goes in a pre-dryer for about 35 days, which takes it down to about 30% moisture.
The training process provided by Lignomat was “fairly extensive,” said Mike. “They were here to install and train…they did not leave until we were 100 percent satisfied and comfortable with it,” which was “a little bit unusual” compared to some other suppliers, he noted. Some suppliers will allocate a certain number of days or budget amount to get new equipment up and running and are “itching and running” to get to the next installation, Mike observed.
One of the best features of the Lignomat kiln control system, said Mike, is that it records a history of the kiln cycle, and the data is available in both text and graphs. “If anything goes wrong in the kiln cycle, it records what happens in the kiln every five minutes.” For example, the system will record if a fan stopped reversing, on what day, at what time, allowing the company to make adjustments in the kiln operation to compensate for it.
Another benefit of the Lignomat system is that it can be accessed remotely by company personnel or Lignomat representatives. For example, Lignomat representatives can access the system from their offices to provide troubleshooting assistance. Also, if the kiln operator wants to check the status of kilns before going to bed, he can dial into the system from a laptop computer at home to check on them.
The Lignomat kiln control system uses one independent microprocessor-based controller for each kiln. Wireless technology allows for completely digital design, meaning low sensitivity to electrical noise. The system features complete diagnostics in order to protect the value of the lumber. It allows separate schedule schemes to address different situations during drying, equalizing and conditioning, and different schedules can be linked to create exactly the type of schedule the kiln operator wants to run. Kiln cycle data is recorded and can be displayed with an unlimited number of variables in both text and graphs.
The Lignomat kiln control system considers the complete drying environment. For example, the system communicates with variable speed drives to change fan speed, depending on the moisture content of the lumber. Fan speed can also be reduced, depending on rate structures or demand load considerations. This capability can reduce energy consumption and demand charges. The Lignomat kiln control system also optimizes steam. It will distribute steam according to a predetermined prioritization schedule. The software program considers steam pressure and allocates available steam.
Unitemp Dry Kilns, based in Arkansas, has been engineering, designing, manufacturing, building and servicing dry kilns since 1943. The company supplies dry kilns, pre-dryers and specialty drying systems for both hardwoods and softwoods. Kilns range in capacity from 20,000 board feet to 165,000 board feet. Unitemp puts a strong focus on flexibility to let customers choose between different types of structures and heat sources to fit their requirements and budget.
“They do a great job,” said Mike, and service is “Johnny on the spot.”
“The kilns are quality workmanship,” he added. “We’re obviously satisfied with them or we wouldn’t keep buying them.”
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