It would be a phenomenal undertaking: To comply with EPA and state emission standards, Roanoke Cement Company faced a major overhaul - yet the company could not afford to slack off production. Every pound of their normal output of more than a million tons of cement per year was crucial to the steady customers who count on the consistent quality of Roanoke products.
"This is the only plant in Virginia," says William Wall, Roanoke plant manager. "We have been sold out for the past five years, and we keep production at a maximum. One hour of downtime costs us right at $8,000."
In the middle of the major equipment overhaul, Roanoke also undertook a complete lubricants overhaul, made possible by Shell technical experts from Westhollow. Keeping the cement operation running at full steam during the entire overhaul process was a remarkable exploit; to understand how remarkable, you have to know a bit about cement making.
Dig, Grind and Cook
Those are the three basic steps in the recipe, and it sounds simple until you look at the quantities: 300 tons an hour.
Digging takes place at Roanoke's quarry, 3000 acres of rolling hills just across the road from the plant. After limestone and shale from the hillsides have been quarried and crushed, they are blended in correct proportions and sent to one of two raw mills for grinding. Walk into the building with these four-story behemoths, and you can feel the scream of metal rollers and splintering rock in every cell of your body - even with ear protection.
The ground-up raw mix is next cooked in four small kilns dating from the fifties and one large kiln commissioned in 1975. All of them are inclined rotating cylinders, coal-fired to temperatures close to 3000°F. Here impurities burn off and the raw mix sinters into "clinker," marble-sized chunks of lava-like material. After cooling, the clinker is ground to fine powder in an enormous ball mill, and the finished cement powder is ready to be packaged into tank trucks, rail cars and sacks.
The Roanoke Challenge
The problems that Roanoke had with energy consumption and waste gas emissions centered on the kilns, which operated inefficiently by current standards. The four oldest kilns were simply too small. The large kiln, which is two-thirds the length of a football field, could handle as much as the total of the other four, but not enough to meet Roanoke's total demand.
"We now have one of the strictest air permits in the country today," says Wall. "We wanted to bring the plant up to meet the same air standards you expect in a residential community, and we had to make some dramatic changes to do it."
The solution to both emissions and energy costs was a $40-million redesign of the plant. Without interrupting production, the capacity of the large kiln would be doubled and the four old kilns phased out.
Doubling the capacity of the big kiln would entail faster rotation, a strain on bearings and lubricants and a potential threat to continuous operation. And the kiln's old "traveling-grate" pre-heater would have to be replaced with a modern calcining tower. (See diagram.) Roanoke erected this 325-foot building directly above the large 3,000-degree kiln without ever stopping kiln operation, a new definition of "hot work."
Roanoke is one of only two cement plants in the US using a six-stage calcining tower, and it is very efficient. With the new tower in place, raw mix is ready for the kiln in 20 seconds instead of the 20 minutes the old pre-heater required. Both energy consumption and emissions are dramatically lower. And when the old kilns are shut down for good, energy requirements will drop to roughly half of what they were originally.
It's a remarkable achievement.
"We were here 12-14 hours a day during construction, and the plant manager worked 16-18 hours a day," says Jim Kern, one of three maintenance supervisors for Roanoke. "From December 1 of 1995 to June 15 of 1996, I had 11 days off." The changeover to Shell products took place right in the middle of all this.
New Lubes in a Hurry: a 35,000-gallon opportunity
"We offered the business to three different companies by asking for a lube survey," says Wall. "The only one that responded was PMI [Petroleum Marketers, Inc.] and Shell, and that bought my business. That and the customer service that they give us on a continuing basis."
The PMI territory manager on the Roanoke account is Winston Spaulding.
"I've been with PMI about eight years," says Winston, "and Roanoke Cement was one of the first accounts I targeted. Mobil had been in there since the 1940s. I got my foot in the door with Shell TELLUS(r) 68, replacing drums of a Mobil product with a 1000-gallon tank. They had to hoist the Mobil product in drums up four or five levels in this one area, which was difficult and dangerous. We put in a bulk tank, piped the oil up 60 or 80 feet, and ran reels to the equipment. The next product we sold was OMALA(r) for the gear reducers in their crushers."
By the time the new plant was built, PMI and Shell had captured about 10,000 gallons per year of Roanoke's lubricant business, while Mobil retained another 10,000 gallons in the main part of the plant. Now there was an opportunity to get all the business for both the old and new plants, because William Wall wanted to consolidate with one supplier. And he needed lubricants that could withstand the more severe operating conditions of the new plant.
The "Instant" Lube Survey
"Winston gave me a call just before the National Sales Meeting in February," says Shell Area Manager Don Schmid. "He told me we had a tremendous opportunity at Roanoke Cement, not only to add to our existing business, but also to acquire Mobil's existing business. We knew time was of the essence, so we reacted right away. Three of us from Shell joined Winston and Ruben Terry at the plant, and we spent two and a half days gathering information."
Back at Westhollow, the Shell team turned to Orion to finish the task of updating Roanoke's old survey information, checking equipment specifications, cross-referencing products, consolidating lubricants and printing survey results. One week after the Shell team arrived at the plant, the new lube survey was complete for all of Roanoke's equipment, old and new, 1000 separate pieces.
"The rest is history," says Don. "We were awarded the business, more than 30,000 gallons annually."
"We got nothing but great support from Shell," says Winston Spaulding. "It was very fast turnaround. It was incredible."
"It wasn't all that difficult," says Harry Erbe, a member of the lube survey team. "The people at Roanoke were very helpful, and Orion makes choosing the correct lubes easy. Now whenever Roanoke changes something, they let us know, and we make the changes in Orion and give it back to them."
What does Roanoke think of the Orion survey?
"The conduct of the survey was very professional," says Wall. "Shell supplied enough people so it didn't require me to put a lot of my people on the job. We've had other surveys where it seemed like we were doing all the work.
"With the survey, we've been able to get down to one supplier, so we don't have all these different types of oil spread all around the plant. "Shell gave us a lot of new suggestions that allowed us to use a less expensive oil, to go to a petroleum-based product instead of a synthetic. We were able to consolidate. All in all, PMI and Shell have helped reduce our overall costs."
And More...
Today, PMI supplies close to 35,000 gallons a year of industrial lubricants to Roanoke Cement, of which about one-third are synthetic. "They're running hard all the time," says Winston, "and they have places that are hard to get to. They don't want to change the oil but once a year, and synthetics are worth every penny."
Wall would say that about all the Shell products his plant is now using: "We are a 24-hour operation, 365 days a year, so we rely very heavily on the lubrication products we get," he says. "We've seen a very drastic decrease in gear and bearing wear from what we've had in the past as a result of the change-over to Shell products. We do gear analysis every year, where we tear the equipment down and look at the gears and take pictures of them. And we're also seeing a whole lot better wear on the hydraulic cylinders in the raw mills. Some of this is due to the bulk storage we've gotten from PMI - we don't have people carrying 5-gallon cans around where the oil can get contaminated.
"It's imperative that we keep running. That's why we're so particular on the lubrication we do," Wall concludes. "We feel that with the quality of lubricants that Shell provides and the service that PMI gives us, that's where we need to be."
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