The leading voice for the crushed stone, ready mixed concrete, sand and gravel, and cement industries' community.
PELA is a 10-month hybrid program with online and in-person educational sessions and networking opportunities.
Careers in the Aggregates, Concrete & Cement Industries
The Pennsylvania Aggregates and Concrete Association (PACA) is the industry’s unified voice, representing more than 200 member companies across the state.
Creating a unified and strong voice for our industry.
PACA monitors and analyzes local, state and federal regulations and advocates for a balanced approach by the regulators.
PACA builds a bridge between our members and our partners at PennDOT, and the Pennsylvania Turnpike Commission along with Pennsylvania’s construction industry to further the use of our materials to the benefit of the commonwealth.
One of the most effective tools in government relations for an industry is a robust advocacy/grassroots strategy.
In the last legislative session, we contributed over $275,000 to our political champions.
November 2025 at Hotel Hershey in Hershey, PA (PACA members only event).
PACA offers comprehensive concrete certification programs for ACI, NRMCA, and PennDOT in the central Pennsylvania area.
Membership has its privileges - most of PACA's events are open to PACA members only.
PACA conducts numerous education and training events during the year.
Choose concrete for your next parking lot project.
Streets built with concrete are built to last, consider concrete for your next project.
Concrete's strong, resilient and the choice for your next building or bridge.
PACA works with the National Ready Mixed Concrete Association (NRMCA) to convert your parking lot or building project to concrete without hurting your bottom line.
PACA drives a member-approved strategic plan to increase market share and engages specifiers and owners on the value of concrete in their projects.
This program provides free continuing education to the design and specifying communities. There are currently four courses available, ranging from 30 minutes to 60 minutes focused on the cement, aggregates and concrete industries. You'll receive a certificate of completion once you pass a quiz. The bookmarking feature allows you to leave the course and resume where you left off when you return.
Despite an increased use of supplementary cementitious materials (SCMs), demand for Portland cement continues to grow. In the past decade alone, Portland cement production increased from 75 to 95 million metric tons in the United States.Clinker coolers subsequently reduce temperatures to several hundred degrees. Clinker coolers:
Allow for internal heat recuperation: clinker to combustion air
Reduce clinker temperatures to facilitate clinker processing
Deliver cooling velocities that avoid adverse clinker phases and crystal size
After cooling, the clinker is ground and mixed with small amounts of gypsum and limestone. The resulting Portland cement is so fine that a single pound contains about 150 billion grains.
Heat retained during the cooling process is one measure of the efficiency of a unit. Ease of maintenance is another. Service life is also important.
Heating raw materials to such high temperatures is energy intensive. The cooling process is as well. To improve cooling efficiencies, cement plants either modify existing equipment or install new coolers. The quest for increased efficiency and reduced emissions drive decisions to invest in clinker cooler upgrades. Cooler upgrades benefit from the use of standardized parts.
Cement plants employ a variety of cooling technologies. This is due in part to the long lifecycle of cement plants. The two main types are grate coolers and rotation coolers.
A grate cooler infuses a horizontal clinker bed with cool air from below. This facilitates heat transfer from the clinker to the combustion air. Maximizing cooling velocity controls crystal size and reduces adverse clinker phases. The largest grate coolers handle more than 10,000 tons of clinker per day. Modern tech includes more sophisticated plates and enhanced forced aeration. To save energy, the trend is toward wider and fewer grates and the use of less cooling air.
Rotation coolers feature a cylinder tilted about four to seven degrees. A gear ring drive drives the cylinder. A support ring prevents it from sliding in the axial direction as clinker moves through the unit.
There are two key issues with rotation coolers. They have limited capacities, maxing out at 3,000 tons per day. Also, they are typically not compatible with modern precalciner tech.
Claudius Peters is a global supplier of clinker coolers, equipment modifications, and components. Its 800 clinker coolers deliver capacities of anywhere from 500 to 13,000 tons of material per day.
The firm develops modern, more efficient cooling technology. It draws on its half-century of experience to inform current research. Its newer ETA cooler gets deployed with new kiln lines as well as existing equipment. It includes an HE module – a static grate in the inlet zone. The company has already performed more than 90 ETA modifications.
Designers work to tailor designs to the core machine’s environment. Customized designs typically include updates to the:
support structure
fan ducting
hydraulic piping
chloride gas bypass duct to the new clinker cooler
Typical cooling units feature horizontally arranged lanes. Updated designs raise the clinker bed to make heat exchange more effective.
A moving floor allows for clinker bed heights of more than one meter during operation. This maximizes thermal efficiency while reducing cooling air requirements. It is important to maximize the aeration area by optimizing lane widths. Cast Mulden plates reduce pressure loss, and they reduce clogging. Robust designs limit red river and clinker spillage.
ETA lane units are installed on a support structure outside the existing cooler casing. They are then pulled inside to their final position on rollers.
Clinker cooler upgrades typically increase throughput and energy efficiency. In turn, the latter reduces emissions.
The Mokra cement plant opened in 1969. The plant’s existing grate cooler was inefficient, due in part to a clinker bed height of only two feet. Higher demand for cooling air reduced thermal efficiency and increased CO2 emissions. Existing equipment was also getting more expensive to maintain. Also, the parts were increasingly hard to come by.
In 2020, the principals signed a contract for one of Claudius Peters ' 5th generation ETA coolers. It will make the pyro line more energy-efficient and therefore more sustainable.
Star Cement is the largest cement producer in northeast India. Engineers wanted to increase clinker production. However, they were stymied by older grate coolers that limited throughput. Excessive clinker exit temperatures also exacerbated the production bottleneck.
Management sought a quick solution that could occur during a scheduled shutdown. A CB cooler with a Wave Grate was exactly what they needed to increase production. Reduced pressure drops across the Wave Grate cut power usage while increasing cooling airflows. Specifically, the upgrade reduced clinker temps by 50˚C. Capacity increased from 8,500 to 9,000 tons per day. The upgrade eliminated the production bottleneck.
The Pennsylvania Aggregates and Concrete Association (PACA) reports on industry innovation on this website. This includes the ongoing quest for carbon neutrality. The team at PACA welcomes your questions about your upcoming concrete project. Please contact us for assistance!
February 22, 2024
Proficient carbon calculations are increasingly important as “Buy Clean” legislation proliferates. New York and Colorado are among the states that now require carbon calcs for public projects. An estimated 40% of emissions are from the built environment. According to one estimate, the planet’s total building floor area will double by 2060. This makes the concrete industry a key player in the quest for net-zero emissions products and projects.
February 15, 2024
The Natural Resources Defense Council (NRDC) notes that cement production is “so carbon intensive that even though cement makes up less than 15% of concrete by weight, it accounts for 90% of concrete’s carbon footprint.” The use of fossil fuels to fire cement kilns is a key source of these carbon emissions.
February 08, 2024
In the quest for reduced greenhouse gas (GHG) emissions, everyone has a role to play. In the concrete industry, this includes everyone from manufacturers to contractors, and from trade associations to governments. Here is a review of some of the major initiatives impacting concrete’s sustainability.
February 01, 2024
Ordinary Portland cement (OPC) requires high-temperature calcination of limestone. It is possible to use various emissions-reducing pozzolans in concrete. Fly ash comes from coal-fired power plants. Ground granulated blast furnace slag (GGBFS) comes from steel mills. Another SCM is metakaolin derived from kaolin.
The program is delivered in one (1) module and it should take approximately 30 minutes to complete. You will receive a certificate of completion once you pass the quiz. The bookmarking feature will allow you to leave the course and resume where you left off when you return.