BACKGROUND: We are proud of PPC's expertise in the environmental field. We have been in business since 1967 and have installed over 400 electrostatic precipitators in a wide variety of industrial applications. Our projects have been as large as $10,000,000 and we have bonded contracts of that size. Our electrostatic precipitators have found their way into a wide variety of major companies whose businesses are in the cement, foundry, petroleum, mining, steel, glass furnace, and wood industries. We have also done projects for all levels of the government.

Unlike its competitors, PPC not only designs and engineers its electrostatic precipitators, but also fabricates them on its own facilities and then installs them with its own field staff and employees, where possible.

PPC's products are unique in that they are designed and engineered to minimize field erection costs and time through the use of the modular production manufacturing techniques developed by PPC. For example, PPC's units have the surfaces insulated and lagged at the factory with the result that only flashing weld seams need to be insulated at the erection site. Another PPC modular technique is to pre-wire as much of the low voltage on the unit's roof which in turn eliminates costly and time consuming field wiring and conduit.

PPC's management feels that the practice of its competitors of subcontracting the fabrication, insulation and field assembly of the electrostatic precipitator is a poor one. The subcontracting process does not permit the firm to maintain the vital control over every step of the fabrication, insulation and installation process which is so critical if a quality product is to be delivered to the customer at a fair price.

MODULAR SHELL DESIGN: Anything that can be done to reduce the installation time and insulation time on the jobsite, translates into savings in both time and money. In the past twenty five years, PPC has been able to steadily reduce the time required to install an electrostatic precipitator. Most of the early units were smaller sized units which more readily are adaptable to the modularization concept. In recent years, we have been able to apply the concept to electrostatic precipitators of ever increasing size. We now have units processing in excess of 500,000 acfm.

In 1975, PPC built the first electrostatic precipitator for the pulp and paper industry for Westvaco in Wycliffe, KY. This unit is still in operation. Recently, we have built electrostatic precipitators in the pulp and paper industry for power boilers in Kapuskasing, Ontario, Smooth Rock Falls, Ontario, Prince George, B.C. and Skookumchuck, BC
PPC is currently applying modular technology to a black liquor recovery boiler for Canadian Forest Products at one of their Prince George mills. The design is well underway and fabrication is underway with installation to follow in the summer of 2002.

The shell of an electrostatic precipitator represents a substantial portion of the cost of a unit. The electrostatic precipitator shell is nothing more than a gas tight box with the active elements hung from the roof of the box. If the shell can be delivered to the jobsite in substantially larger pieces, with the insulation and lagging installed, then the time to construct this portion of the unit can be dramatically reduced. This reduction in erection time is doubly important since a crane is being tied up along with a number of field personnel. Since the shipping envelope throughout most of North America is 12' wide x 11.5' high x 48' long, the shell must be cut into pieces this size or smaller. Smaller pieces mean more field time and more crane time - so every effort is made to keep the pieces as large as possible. By careful design, the shell pieces maximize the shipping envelope and minimize the assembly time - thereby minimizing the field cost. We have even found appropriate locations for field lifting lugs and other rigging essential in reducing installation time. The seams in the shell can be insulated and flashed after the crane is released, thereby reducing crane cost.

The insulation which is so important to recovery boiler electrostatic precipitators, is factory applied to the maximum extent possible. Most shell pieces can be completely insulated except for a small seam at the field weld joints. This area is insulated often times on the ground prior to lifting the components into place on the unit. Complicated insulation areas are done in the shop rather than from scaffolding - resulting in a much better job than could otherwise be obtained - at greatly reduced cost to the customer.

The application of 8" of insulation in multiple layers with thermal breaks for the shapes that hold the lagging in place are also much easier to install in a shop rather than from scaffolding on a unit already in place. A much better fit is possible in the shop as well.

Hopper heaters, motion sensors, etc. are all more economically installed in the shop, with much better fit of the insulation and lagging.

The modular technology can also be applied to the installation of the access (but not the fabrication). PPC installed insulation filled support members on their power and other wood fired units to make the installation of the access a simpler process. These access support points are pre-painted, and even have support clips where necessary to speed up the installation process. Once the basic shell is assembled onsite, the inlet and outlet nozzles are assembled at grade then installed in one piece on smaller units and in only two-three pieces on larger units. While the nozzles are at grade, the seams required by the shipping constraints are insulated and flashing installed. Once the nozzles are installed, the entire shell with nozzles are squared and seal welded from the inside. The average time required to reach this stage on a 200,000 pph boiler is about a week with a four man crew, not including the crane operator.

At this stage the assembly seams can be insulated and the collecting plates and discharge electrodes can be installed. The collecting plates are arranged in bundles of 3 or 4 for recovery boiler units and 5,6 or 7 for power boiler units. By installing the plates in bundles instead of individually, the process is significantly faster. The electrodes are temporality attached to the collecting plates and installed with them - to further decrease the erection time. Once the collecting electrodes are in place and the upper discharge electrode support racks are installed, the unit is ready to have the roof sections installed.

ROOF SECTIONS: The roof sections have been factory insulated with up to 10" of 8# density mineral wool, and covered with a 1/4" thick treadplate walking surface. Units without roof enclosures have the treadplate sloped to shed rainwater. In the factory, PPC installed the transformer / rectifier units, insulators, collecting plate rappers, discharge electrode rappers, manways, key interlocks, buss bars, buss ducts, etc. After the installation of all of these items, the roof sections are primed and finish painted and loaded on the trucks. PPC manufactures three configuration roof sections: (1) An open roof without any cover for most climates, (2) "carport" style covers for warm moist climates or for clients that just want a little more protection for the equipment, and (3) totally enclosed - weather enclosures for colder climates. These enclosures are all factory installed, painted, and shipped with the lagging installed.

ELECTRICAL: Probably the most cost effective thing we do and the item for which we get the least credit, is the factory installed roof electrical wiring and conduit. PPC installs the power feeds, for the purge air blowers, the power feeds for the discharge and collecting electrode rappers, the wire and conduit to each rapper and, on smaller units, a roof mounted power distribution enclosure. PPC also provides and installs a roof mounted electrical equipment enclosure for PLC control by the customer - all of this electrical work is part of our standard package and saves the customer enormous costs for the field electrical work. To assist the customer, PPC provides a very detailed electrical drawing package. This package is so complete - it is ready for distribution to the contractors as soon as it is received.

The final mechanical steps are to installed the inlet ductwork and ash system. In the case of the recovery boilers, the scraper drags are shipped right on the floor section of the electrostatic precipitator - in place - ready to mount the drive units. The drag conveyors and rotary airlocks are mounted after the electrostatic precipitator is complete.

Touchup painting and miscellaneous housekeeping items complete the job

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