COOLING TOWER LIFE EXTENSIONSpringfield Plant

May 2014

1. Background/History

The cooling tower installation at the Springfield plant consists of four independent cells manufactured in 1996 by Baltimore Air Coil (figure 1). The tower has been in continuous service since its installation 18 years ago. Each cell was coated with a compound called “Baltibond” designed to inhibit the corrosion process and extend the life of the cell basins (sumps). The cooling tower installation rests on a support system of steel columns and girders at an elevation of approximately 3 feet above the roof surface to accommodate condenser water supply and return pipe runs. The engineering staff has performed regular, documented maintenance on the cooling tower such as fill and sump cleaning, belt replacements, etc., on an annual basis for at least the last 10 years. Cell 1B motor and fan components were overhauled in 2013 but no other overhaul maintenance has been documented. To date, neither recoating of any exterior surface of the cooling tower nor the supporting steel structure has been documented. The cooling tower itself is essential to the printing process because the condenser return water it supplies to the chillers is integral to producing process chilled water to the presses at the correct temperature. Without an operating cooling tower, printing any product would not be possible.

Figure 1

2. Current Condition

The Baltibond coating has continued to deteriorate and has peeled away from the metal surfaces particularly in the water sumps (figure 2) resulting in corrosion and water leaks in all four cells.

Figure 2

Continuous exposure to the elements, the chemically treated condenser water flowing over tower structures, and deterioration of the PVC fill material has exposed exterior shell components of each cell to a harsh environment and has resulted in moderate corrosion on the exterior shell (figures 3, 4, 5).

Figure 3 Figure 4

Figure 5

The cooling tower supporting steel structure is experiencing moderate to severe rust in addition to cooling tower cell deterioration. The condenser water used in the cooling towers contains various chemicals such as biocides to control the growth of bacteria like the type that causes Legionnaire’s Disease. These chemicals tend to accelerate the corrosion process when they come into contact with uncoated metal or coated metals when the coating has been compromised. Both the main girders are experiencing moderate to severe surface rust and exfoliation that needs to be remediated before it leads to structural failure (figure 6). Many of the transverse supporting girders are experiencing severe exfoliation rust which has led to structural failure of one with other structural failures soon to follow (figures 7, 8, 9). These transverse girders provide the supporting structure for the maintenance platforms that surround the entire cooling tower. The maintenance decks are essential equipment for the engineering staff to properly maintain the tower. Finally, the mechanical components in each cell such as the main fan shaft, main fan shaft bearings, fan and drive motor pulleys, and belts need to be removed and replaced (figure 10). These components are what failed in cell 1B during 2013. The main fan shaft bearings in cell 1B had corroded so severely that they disintegrated jamming the motor and snapping the drive belts. Inspection of the remaining cells revealed deterioration similar to cell 1B but not as advanced. Overhaul of each remaining cell was added to the maintenance plan for later in 2013 and 2014 but subsequently reclassified as a life-extending capital project for 2014.

Figure 6Figure 7

Main tower support Girder (1 of 2)

Severe exfoliation on transverse deck structure

Figure 8

Figure 9

Failed maintenance deck structural stiffener

Figure 10

Figure 11

Motor and fan pulleys

500 lb 40 Hp Motor

Typical corroded shaft

12 foot diameter fan

3. Proposed work scope

We have received a proposal from Columbia, MD based vendor Cooling Towers & Heat Exchangers, LLC, an authorized Baltimore Air Coil dealer, to perform the following life extending repairs to the existing cooling tower cells.

1. Main fan component replacements including motors, bearings, motor and fan pulleys, fan shaft, and drive belts for the three remaining cells. Price: $11,370 per cell.

2. Resurfacing of cell cold water sump basin, replacement of lower level of fill and fill supports, and remove all sediment and foreign material from the cell and remaining fill. Price: $12,092 per cell.

3. Hot water basin repairs and exterior surface touch-up. Price: $3,091 for all four cells.4. Repairs and resurfacing of the structural steel supporting the tower to be accomplished by a

third party vendor who specializes in structural steel preservation. Price: $26,710.5. Electrical conduit repairs. Price: $1,081.

Total cost of entire project less contingency is $124,730 (this price is good until 7/2/2014).

We also received a budgetary quote on complete replacement of each of the four cells. The vendor estimated the price of replacement at $1.0M to $1.2M not including structural steel repairs.

4. Outcome/benefits

The two primary benefits of proceeding with this project is that we can preempt cooling tower cell failure avoiding the cost of loss of use of the entire facility and extending the life of the cooling towers avoiding the cost of replacement. If the cooling tower fails during peak summer time heat, the presses will become unusable due to lack of cooling water. Proceeding with this project is expected to extend the life of the cooling tower by at least 10-12 years. Secondarily, our ability to operate production equipment that uses compressed air will be adversely affected because cooling tower water cools the air compressors. We do have city water backup for the air compressors, but the water flow from the city will only sustain two of the five compressors on site. Finally, the cooling tower is vital to air conditioning the plant, and without it, we will not be able to run chillers, and therefore air conditioning resulting in extremely high temperatures and humidity inside the plant.

5. Recommendation

Approve the capital request and proceed with the cooling tower life extension project with a targeted completion date in the late 3rd quarter or early 4th quarter 2014.