The producer chose the Sloan location primarily for two reasons: Much of the future growth was forecast south of Las Vegas and in Henderson to the east. Also, a nearby Aggregate Industries facility supplies aggregate, while another aggregate pit is planned in the area.
Cemex chose a Con-E-Co wet-dry batch plant. “We had many Con-E-Co plants operating at the time, so we were familiar with the equipment, reliability, and speed it provided us,” Land says. Also, for maintenance, existing parts could be used in the new batch plant.NEED FOR SPEED
Because of space constraints, Cemex was forced to remove its portable plant from City Center a year sooner than planned. “The City Center project alone could demand 1000 yards per hour, with equal or greater demand in the outlying areas,” says Land. “So the Sloan plan allowed us to continue to service City Center after that plant was gone, and also the remaining volumes, without any impact to our customers. That was huge.”
The plant has a 15-yard wet mixer drum, combined with a dry-batch alley and automated material handling system. Cemex has produced 400 yards/hour at the plant on a trial basis and has sustained 350 yards/hour. “We've yet to be called on to do 400,” Last says.
Aggregate was a major issue for the new plant, as it comes in various types and sizes. “There is a huge disparity in aggregates,” Last says. “In the same pit you can get different qualities of aggregate and different qualities from one pit to another. It's amazingly different. Aggregate versatility and its handling was critical for us.”
The plant's Noble Bin Fill system has the ability to batch seven different types of aggregate at any given time, with two direct feed belts for primary materials and five auxiliary aggregate feeds through an additional belt. Aggregate ranges from 3/8 inches to 1.5 inches.
Because Cemex was already acquainted with Con-E-Co batch plants and their Command Alkon controls, the learning curve for employees was “minimal,” explains Last.
“There was more of a learning curve with the material handling system because we had no experience with it,” he adds. With assistance from Dave Humphrey Enterprises Inc., which consulted on the project, “the operators quickly picked it up and had it up and running with no problems. It's working very well for us.”
An unanticipated issue was the height of the plant as it relates to nearby Henderson Executive Airport. The Federal Aviation Administration deemed a cement silo was too high. “I had to drop the plant 10 feet,” says Last. “We had to redesign. It affected our cementitious material capacity, but it didn't impact the plant's output.”
Manufacturing concrete in the middle of the Mojave Desert brings its own set of challenges, and all revolve around the temperature. With summer temperatures reaching 120º F, “we use lots of ice and chilled water,” says Last.
Ironically, the desert gets surprisingly cold in the winter. There are only about six weeks a year—three in the spring and three in the fall—when cold or hot water is not added to the concrete. The plant is equipped with a Pearson p-15-15W direct fire hot water system.
Last wouldn't say if Cemex has realized a return on its investment. The final price tag was “a little bit over budget, but that was more of a property issue than an equipment issue,” he explains.
“The economic crisis hit Las Vegas harder than anywhere else in the country, and inconveniently, just as Sloan was brought online in September 2007. It obviously created a very difficult financial environment for us and for everybody in the market.”TURNING THE CORNER
While commercial and residential development languishes, concrete is still being used for area infrastructure projects such as solar and wind turbine plants. Federal highway money also has helped local construction.
Flying into McCarran International Airport from the south, visitors can see huge residential projects that were halted in their tracks. The outlines where homes, sidewalks, and streets were etched into the earth are visible.
“We are seeing more building in those locations,” Last explains. “Obviously, it's not coming back as fast as we'd like, but it is showing a slow recovery. It appears the market has leveled off, and the Sloan plant does position us to lead that recovery, so we're excited about that.”