New Orleans Convention Center
Problem: Once a condenser starts to scale or foul, the economics of cleaning and energy loss must be considered.
Typical condenser approach temperatures on one of the four 450-ton chillers, fully loaded, would be about two to three degrees with fairly clean tubes. The casino has been able to monitor the condenser approach and, unfortunately, has had to shut down the chillers frequently to clean the tubes when the approach gets up to six or seven degrees.
Depending on the load, water temperatures and the mud or debris in the river, the frequency of the high approach temperatures would vary. In the summer months all four chillers are needed for comfort cooling on the boat, but summer is also when the river is the hottest and dirtiest. The casino would typically have to shut a chiller down about once a month to brush the tubes just to keep the chillers from tripping on high head pressure. The bottom rows of tubes were even completely plugged in some of the condenser tubes.
Results: The casino installed the Automatic Tube Brushing System on all four chillers in May, 2002. In June, a one-month follow-up showed that the ATB System had not only performed as promised, but had actually improved the chiller performance. At 75% load, one chiller was showing less than half a degree approach temperature. The other chillers were operating at less than two degrees approach.
At the end of July, all four chillers were running at full load. Usually, by this time the chiller operators would have already had to clean the condenser tubes manually because the approach temperatures would have been excessive. With the ATB System installed, approach temperatures on all four units were less than two degrees, which indicates very clean tubes.
In November, another follow-up showed that all four chillers were still operating at less than two degrees on the approach temperatures.After more than a year of operation, the Head of Operations at the casino claims to have received a payback in less than six months.