The modular movement
Portable and stationary washing plants have new competition in modular units from European-based companies. How will the modular model ultimately fit into the U.S. market?
High-visibility safety vests made their way from Europe into the American mainstream. So did portable crushing and screening equipment on tracks.
Now, another European development is pressing into the U.S. aggregates industry: modular washing systems.
“The industry ebbs and flows in terms of what’s popular when,” says Mark Krause, general manager of McLanahan Corp.’s Aggregate Processing Division. “Washing and processing and sand recovery are the hot stuff right now. Some of the classic, portable machines are popular as well, but the trending thing is the whole modular concept.”
The modular washing concept isn’t limited to one European-based company. CDE Global and Terex Washing Systems have both brought plants to the United States, promoting their equipment with showcase events. The companies have made some traction, and they’ve gotten the attention of their U.S. counterparts.
“I think the Europeans with their modular concept are going to sell some plants in the U.S.,” says Jeff Wendte, product manager of washing and classifying for KPI-JCI and Astec Mobile Screens. “The [modular plants] are going to be fixed at a site for five to six months, whereas most portable plants being used here are moving two to three times per season.”
The modular model European-based companies are promoting is still relatively new to the U.S. Do modular plants have a chance to be entrenched in the U.S. industry’s fabric, or will the more traditional portable and stationary models maintain their places?
“The questions long term are does the trend become the norm, or does the trend come and fade,” Krause says.
Healthy debate
Iain Walker, global sales director at Terex Washing Systems, is optimistic about the potential for modular washing systems in the U.S. To him, a modular system offers some advantages that traditional portable and stationary systems do not.
“In the U.S. there’s a lot of tradition with screw classifiers and bucket washers,” says Walker, whose company brought the AggreSand, a system that combines aggregate washing and screening with sand processing, to the U.S. in 2013. “Bringing them an integrated and logical washer is already an attractive point. The next step, and I suppose the thing to really overcome, would be the traditional approach, which is static machines.”
The traditional stationary plants have a number of key components that are independent from each other, Walker says.
“You have the hopper, conveyor and a separate sand-washing unit,” he says. “These are all separate machines, and people are used to that format.”
Those various components take up space, Walker adds, positioning modular plants as an option for producers who have limited space and no place to put a stationary washing plant. In addition, he says modular plants are capable of competing with portable models on serviceability.
“There are a lot of benefits to [modular plants],” Walker says. “The challenge quite often is people consider them in light of mobile machines. By taking what they’re familiar with and compressing it into a new package, they may think there is some compromise. The assumption might be that it’s going to be difficult to service; that the access isn’t going to be good; that it’s going to be too lightweight.
“Realistically, the only way to overcome that is to show them the equipment.”
Setup time and teardown isn’t an overnight task. Walker typically tells producers that AggreSand plants can be moved to a new jobsite in fewer than four days. Their lack of tracks or wheels does slow portability, but portability wasn’t the leading factor in the plants’ design, he says.
“We didn’t set out to create a fully mobile system,” Walker says. “It is readily portable. It easily sets up and breaks down for low loaders or for shipping transport.”
According to Wendte, portable washing plants still have the edge on modular ones in terms of transport time.
“Some of the more highly portable plants, including the conveyors, can be broken down in the morning and on the road that afternoon,” he says. “These modular plants, which are built in modules to fit in containers, may have six to eight pieces that need to be offloaded from a truck, set in place on a pad and bolted together through the use of a crane.”
Although a modular plant’s setup differs from a portable plant’s, Krause sees a number of positives in the modular design.
“It’s totally engineered so it comes together as a complete plant,” he says. “We’re seeing a lot more demand for that in everything we do. It has a good price point because you’re looking at low-cost global manufacturing. It goes in six containers, it shows up on your site and a dealer can stock it. You don’t have to pay for special engineering if you don’t need it.”
A modular washing plant has its downsides, Krause adds, arguing that they produce less and are more difficult to maintain than a stationary setup.
“The biggest constraint I see is the smaller conveyors,” he says. “You’re talking about short conveyors.”
Still, Krause says the model has piqued McLanahan’s interest enough that it plans to bring its own modular washing plant to market.
“Are we going to do it exactly the same way as others? No,” Krause says. “This has not strategically been McLanahan’s core business. We will continue to focus on our core because that’s our bread and butter, but there’s enough volume in the other side of it.”
Other trends, issues
Modular systems aren’t the only trendy development in the aggregates washing world. Wendte says some producers are asking for larger, higher-capacity portable plants that require a custom build.
“Over the last five years or so we’ve had several requests for 800 tph portable wash plants,” he says. “The problem is the equipment is physically so large that it’s difficult for it to become portable.”
A portable plant’s limit is probably about 800 tph, according to Wendte. Once a plant enters the 1,000-tph range, he says a more traditional stationary setup is preferable.
“If you’re running 800 tph through a plant, there’s a lot of wear that occurs because of the nature of portable plants,” he says. “They’re very compact, so some of those wear areas – liners, for example – can be very difficult to get at. You can make it easier to access those areas on a stationary plant where you’re using a lot of gravity.”
Building a portable plant that approaches 800 tph in capacity requires creativity on the part of designers and manufacturers, Wendte adds.
“We’ve had to think outside the box and have been incorporating cyclones, for instance, and dewatering screens in portable plants that were not very popular in the U.S. market five years ago,” he says.
Some producers approach their next plant purchase from another vantage point, according to Krause.
“It isn’t as much about the tonnage as give me as many tons as I can in this lower cost, lower commitment piece of equipment,” he says.
According to Wendte, portable clarification equipment is growing in use, as well.
“What I classify as portable clarification equipment is thickeners,” Wendte says. “There are a couple of companies who will offer small thickeners. The problem with that is they are fairly limited in the amount of water they can handle. It’s kind of a double-edged sword because you can get it all portable but you’ll be low in capacity.”
Water availability is a growing issue for a number of U.S. producers, as well. A lack of available water forces manufacturers to get creative for producers in certain locations.
“The first step is they start looking at things like thickener tanks, where you settle out the solids and reclaim the majority of your water a lot quicker than a settling pond,” Krause says. “This is more of a natural system.”
Filter presses are another component producers turn to when water availability is an issue.
“These take out most of the solids and recycle the most amount of water that you possibly can,” Krause says. “That means you need a minimal amount of fresh water or outside water to continue your operation. Right now, the states are limiting what [producers] can do with water.”
Michael Honea, process manager at Haver & Boecker Canada, agrees water availability is an issue for some producers.
“The biggest trend we’re seeing is the need to reduce water use due to drought and restrictions, especially in the southwestern United States,” Honea says. “Those changes cause producers to seek out the most efficient machines they can so they stay within regulations and are as profitable as possible.”