Texas-based Lone Star Aggregates transforms their Florence operation with a CDE plant
Lessons in Water Management...
In 2018, Austin-based Asphalt Inc., LLC expanded its operations in Texas to further strengthen its foothold in the region. With three distinct divisions – Lone Star Aggregates, Asphalt Inc., and Lone Star Paving – the vertically integrated company offers a full asphalt paving service throughout Central Texas, from aggregates quarrying to the production of hot mix asphalt that supplies its own paving crews.
Its aggregates division, Lone Star Aggregates, has two quarries, one in Florence and the other in New Braunfels, commissioned to supply its asphalt plants with the highest quality sand and aggregates in Texas.
The Lone Star Aggregates quarry in Florence is home to a deposit of heavy clay-bound limestone. Given the company’s core values underpin a commitment to producing superior products, it required a fitting solution to extract high-quality washed and graded aggregates from the available feedstock, as Director Thomas Playfair explains.
“Our challenge here at this site is the formation that we are in. Our core value is to make a superior product and to be able to do that you have to have a superior aggregate.”
To meet the expectations of its customers it was essential for Lone Star Aggregates to overhaul its processes. It sought to address inefficiencies and limitations stemming from its existing settling pond water management system and to do so enlisted the support of wet processing experts CDE to help upgrade its equipment and operation.
The Importance of Water Management
CDE Business Development Manager Tom Wick says overcoming challenges with water management and limited water availability on site is central to optimizing plant utilization and extracting maximum value from available resources.
“One thing you need in the aggregate business is clean water,” he says. “Lone Star Aggregates was trying to recycle their water in a settling pond system, and it wasn't enough. Settling ponds incur substantial maintenance costs and, depending on the setup of the site, significant investment in equipment and manhours to ensure a consistent supply of clean water is fed back into the plant.”
Settling ponds require constant maintenance. During the normal operation of a plant they accumulate sludge, silt, and other solids that must settle and separate from the water before its removal. Once settled, these solids restrict the water storage capacity of the pond, requiring dipping with a long reach excavator and the inevitable double handling of materials.
Following a comprehensive site audit, CDE developed a custom water recycling solution tailored to the site-specific needs at the Florence quarry.
Wick says, “Lone Star doesn't have much water on this site so they need to recycle every drop of water they can.
“We knew the combination of an effective water management system with cyclone technology would eliminate the loss of fines, retain every last valuable grain of sand, and deliver improved operational efficiency.”
CDE proposed a custom solution that could be integrated with the existing plant at Florence quarry, an important factor in the design process for Lone Star Aggregates.
“The design process here was real simple. CDE came out, took samples of our material, looked at the existing equipment we had on site and made a real seamless transition on putting the stuff in,” Playfair explains.
The washing plant utilizes a combination of CDE modular technologies, including the dual pass AggMaxTM 251 modular logwasher setup for scrubbing and sizing.
Remaining sand is screened from the AggMax and directed to the sump where it is then transferred to CDE’s EvoWashTM. The EvoWash classification and dewatering system sizes, washes and dewaters the material. More efficient than traditional washing methods, such as sand screws and bucket wheels, the EvoWash captures plus #200 sand.
Playfair says, “The EvoWash has made a very, very clean sand for us; really takes out the clay and also we’re able to catch 200s and put it back into our sand to keep it out of our ponds.”
Central to the system and to addressing the availability of clean water on site is CDE’s A900 AquaCycleTM thickener which allows for up to 90% of the process water to be recycled and recirculated back into the system, offering near-total independence from fresh water supplies.
It means Lone Star Aggregates’ CDE wash plant requires only a small top-up water supply compared to traditional systems and in turn drives down heavy maintenance and handling costs and raises its bottom line through operational savings.
CDE wet processing technology has been instrumental in delivering transformational change for Lone Star Aggregate at its Florence quarry.
The solution has resulted in significant improvements in operational efficiency and minimized the costs linked to inefficient processing practices.
The sand and aggregate plant is producing 400 tons per hour of B, D, and F rock for hot mix asphalt that is supplying the local market and Lone Star Aggregates’ sister company Lone Star Paving.
“We have helped them to produce the highest quality materials for their asphalt hot mix that you can produce,” says Wick.
Manufactured, delivered, installed, and commissioned with dedicated project management, the wash plant is capturing fines that were previously lost to settling ponds for improved yield.
Unrivaled water management has also reduced the need for manpower and maintenance of settling ponds.
Working in Partnership
Playfair says CDE’s direct-to-market relationship with its customers is hugely beneficial.
“By working with CDE you’re able to work with the manufacturer…and by doing that, when you’re doing your construction, things move a lot faster.
Wick adds, “We have our Regional Service Engineers’ boots on the ground coming by to make sure then plant is running efficiently.”
When CDE opened its North America headquarters in Cleburne, TX in 2018 it earmarked significant investment in its CustomCare division which provides customers with industry-leading aftersales support.
The availability of replacement parts is a significant factor in the purchase decisions of its customers. To maximize the efficiency and uptime of its customers plants, CDE’s North America operations includes fully stocked and managed stores of high-wear and consumable plant components that are readily available for immediate dispatch.
Wick says it’s in CDE’s interests to see its customers fully leverage the capabilities of its wet processing solutions.
“CDE operates a customer for life model, this means we continue the customer journey after the plant is installed and commissioned. Expert engineers based locally continue to be available for our customers.”
He concludes, “By investing in CDE wet processing technology Lone Star Aggregates has made considerable steps forward in strengthening its foothold in the region. The Florence quarry plant is supplying clean, consistently graded sand and aggregates to its local asphalt plants to meet growing demand. It has boosted product yield, generating increased revenue, and remedied costly operational inefficiencies to accelerate return on investment.”
Commenting, Playfair says, “I'd highly recommend CDE. You just give them your problems and they give you solutions.”
For more information about CDE wet processing solutions, visit cdeusa.com.