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Georgia Pacific Port Hudson Energy Project Zachary, LA - Georgia Pacific’s Port Hudson Paper Mill produces papers with some of America’s best-known brand names, including Angel Soft toilet tissue and Brawny paper towels, and the mill also makes hundreds of thousands of tons of quality papers for offset printing. But times have changed since the plant was built in 1968. Energy costs have increased dramatically, and environmental considerations have become key drivers in corporate decision-making. Paper mills consume a lot of energy and Port Hudson is no exception. Once one of Georgia Pacific’s most profitable mills, in recent years the Port Hudson operation battled increasing competition from low-cost manufacturers with modern, energy-efficient plants. Like many other energy-intensive operations, the plant did what it could to manage costs by negotiating favorable rates on long-term energy contracts.
As recently as 2005, the plant produced nearly 100,000 tons of solid waste annually, all of it ending up in landfills. Engineers estimated that 75% of that waste could be used as boiler fuel, reducing the plant’s “environmental footprint” as well as its energy costs. Petroleum coke was readily available from area refineries at reasonable cost and it, too, could be used as fuel. A multi-fuel co-generation system seemed to be an ideal solution, but could it be completed before the plant’s energy contract expired? The engineering was complex, and the new system would require time-consuming environmental permitting. As the labor market tightened in the wake of two major hurricanes and management considered the countless uncertainties that might delay construction, they knew one thing was certain: The expiration of the plant’s energy contract would drastically increase operating costs, jeopardizing the very existence of the plant. Success would require a rigorous, extremely detailed execution plan and seamless cooperation among seven contractors. A highly skilled instrumentation & electrical contractor was essential, one with constructability and cost-reduction capabilities, an expert project team, superior safety statistics and an excellent quality program, along with dependable project controls and proven construction capabilities. ISC stood out by every measure. Lump-sum agreements were awarded to ISC for installation of all electrical and instrumentation systems in the new co-generation plant, related fuel-storage and handling equipment, control systems, new power-distribution grid and pollution control systems – much of which had to be done while the mill continued to operate. The contracts provided for three work phases with a total delivered value of $11.69 million. The design called for a 65-megawatt Dresser steam turbine, a unit large enough to power a city of 50,000 households, for example, Biloxi, Mississippi. It would be driven by a tri-fuel boiler capable of producing one-million pounds of steam per hour. The plant’s own sludge and bark waste would supply much of the fuel, along with petroleum coke and, when necessary, natural gas.
ISC’s constructability reviews began to pay dividends during phase two as the foundations were completed and the steel superstructure began to take shape for the ten-story boiler structure. Project planners realized during their reviews that lighting would be required in shaded areas as the structure was built. Careful coordination with the structural-steel contractor allowed ISC to install permanent lighting early in these areas, eliminating the need for expensive diesel generators and shaving up to ten weeks from the project time line. Phase three was scheduled to coordinate with a “cold mill outage” during which ISC would continue installation of the new power systems. These cold mill outages are required every five years for inspections and preventative maintenance on systems that normally operate continuously and cannot be otherwise isolated – and the timing of this one imposed a critical deadline for ISC’s work. Bulk commodities like cable tray, cabling and control systems were installed during this phase in all seven areas of the new facility – the boiler structure, both electrical buildings, the emissions control precipitator, cooling tower, fuel-handling pit, limestone crusher and fuel-storage silos. The pace of work increased as ISC installed the 13.8KV switchgear lineups, more than a mile of 24-inch cable tray and nearly five miles of 13.8KV power cable. Structural and mechanical work continued as ISC mobilized in each area on a schedule carefully timed to expedite completion by minimizing interference with six other contractors. Altogether, the 160-foot, ten-level boiler structure accounted for roughly half of the entire project’s man-hours and materials. Much of the remaining work took place in electrical building one, an adjacent three-story structure that distributes power to the boiler and cooling tower via ISC-installed electrical distribution equipment. The ground floor in this building houses the covered transformer area and drive room where ISC installed two 13.8-to-2.4KV transformers and two 13.8KV-to-480V transformers, five Toshiba variable-frequency drives and a battery-powered uninterruptible power supply for safety shutdowns. Two 13.8KV Siemens switchgear lineups were installed by ISC on the first elevated level, along with two 2.4KV switchgear lineups, two 480V switchgear lineups and the turbine generator control cabinet. Five double-sided Eaton Cutler Hammer motor control centers were installed upstairs on level two, where ISC associates also installed six DeltaV® DCS cabinets and an un-manned computer station that allows the mill’s DCS system to control boiler operating parameters. The new facility would never have received the necessary environmental permits without sophisticated emissions controls to remove wood ash particulates and other pollutants from the boiler’s flue-gas stream. An electrostatic precipitator does the dirty work, and it’s almost as tall as the boiler structure, totaling 120 feet.
But there was much more to be done during phase three. ISC installed power cables and controls for three 2.4KV water-pump motors, three 2.4KV fan motors, and all power and instrumentation for the cooling tower’s chemical-injection systems. In the highly congested turbine-generator platform on an elevated deck above the condensing unit, ISC installed and wired the turbine’s complex instrumentation and control systems, as well as a 300-foot MP Husky cable bus to feed the generator’s output to the new 13.8KV “G-Bus” in electrical building number one. Six transformer / rectifier control panels, a Newendorfer rapper control panel, two Siemens 480V switchgear lineups, three single-sided Eaton Cutler Hammer 480V motor control centers and two DeltaV® DCS cabinets were installed in electrical building two, where power is distributed to the fuel-handling area and the emissions control precipitator. Over in the fuel-handling area ISC installed power and controls for the vibrating hoppers in the truck unloading pits and the automated conveyor systems that carry bulk fuel to the storage silos and on to the boiler furnace. ISC also installed the cables that power the crusher tower where limestone is pulverized for furnace pollution control, as well as its control system. Just eleven months after ISC’s mobilization in a muddy field littered with sheet pile, rebar and heavy equipment, the project was complete. ISC had successfully installed over a million feet of cable; 19,500 feet of cable tray; 94,000 feet of conduit; 11,000 feet of fiber-optic cable; 185 fused disconnects; 1,121 lighting fixtures; 255 welding and convenience receptacles, 70 horn/speaker units for the plant’s Gaitronics Communications System, and 40 electrical panels. ISC’s work had required 24,000 terminations and more than 1,500 instrument mountings, yet every detail had been completed on schedule and without a single electrical problem, lost-time accident or recordable incident of any kind. |
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Time was running out on the most recent of these contracts, and renewal was certain to be far more expensive because the plant’s energy supplier was facing its own problems with dramatically higher oil and gas prices. Fortunately, Georgia Pacific had some natural resources of its own.
With an estimated 18 months of work to do and less than a year to get it done, ISC initiated phase one as early as possible – several months prior to mobilization for structural work. Nearly 210 miles of copper cable were installed during this phase, creating a below-grade grounding grid tied to the pile caps and foundations. ISC worked closely with the civil contractor to coordinate backfilling as the base work was completed, compressing the schedule and minimizing the impact on site preparation.
Most of ISC’s work on this critical system took place on the roof where ISC associates battled the wind and rain to install power cables for the transformers and rectifier system that charge the six large plates which trap the ash before it can escape into the atmosphere. The plates themselves must be cleaned constantly, a process handled by 228 individually powered plate rappers.