Manufacturers in the pulp industry used to be the only companies that handled high volumes of biomass. But in 2022, that’s no longer the case. Sawmills, particularly softwood mills, have grown over the decades to produce literal tons of waste every hour. The same is true of other wood processors: shavings mills, pellet plants, engineered wood plants, RNG facilities, and biofuel plants handle many tons of biomass hourly. Yet, while the volumes have changed, the conveyors companies use to move the biomass have, on the whole, not. The lack of change has proven troublesome for manufacturers unwilling to invest in better-engineered bulk-handling systems because many conveyors on the market don’t serve the demands of companies that handle biomass in the 21st century. And better conveyors certainly exist—conveyors engineered for the rigorous demands of modern 24/7, high-volume work: BE&E’s SMART Conveyors™.
What’s demanded of today’s conveyors?
Today’s industrial marketplace has laid four demands on biomass conveyors:
- They must operate efficiently
- They must run reliably
- They must control dust
- They must satisfy NFPA safety requirements
These demands have existed to some degree for many years, of course. So, they aren’t new. But the priority attributed to them has grown. Manufacturers demand better reliability and better dust control, things our SMART Conveyors™ do well while many other conveyance systems, frankly, do not.
SMART Conveyor™ Efficiency
For instance, expectations for efficient operation have grown over the years, especially as electricity costs have risen and more people have laid value on reducing pollution—carbon emissions and otherwise. The change can be witnessed in the number of pneumatic conveyance systems installed two decades ago compared to now. Many ethanol plants were equipped with these systems in the early-to-mid 2000s when they were built. However, these systems came with massive electrical requirements: a 300 hp motor for one blower was not uncommon. (Pneumatic systems are inefficient because they mostly move air.) Since then, the trend has been to replace these pneumatic systems with mechanical ones, which demand less power.
Of the mechanical conveyors available on the market, our SMART Conveyors™ are among the most efficient, if not the most efficient. They achieve such efficiency because they use power to move material, not overcome internal friction, which is an issue in most drag systems.
Internal friction is low in SMART Conveyors™ because the chains don’t run on steel like other chain-drive conveyors. Instead, the chains run over UHMW (strait sections) and nylon (curves) wear liners in dedicated channels. The plastics provide a low-friction surface for the chains to slide on and then roll over as grooves form during wear. In M- and T- Series SMART Conveyors™, we replace the plastic wear liners in the curves with steel chain guides, which provide a long-lasting surface over which the chains can roll. These guides offer even greater efficiencies in terms of friction.
We further reduce friction in SMART Conveyors™ by maintaining a small gap between the conveyor paddles and the trough. In virtually all other drag conveyors, the paddles drag directly over the bottom pans and against the sidewalls. So even in systems that use UHMW paddles, there’s too much friction.
SMART Conveyor™ Reliability
Conveyor reliability is also increasingly important to manufacturers that handle biomass, perhaps more than efficiency in 2022. The reality in North America is that far fewer individuals are entering trade-based careers than in the past. It’s a trend that spans decades and isn’t likely to reverse soon. As a result, the pool of knowledgeable and experienced maintenance personnel has shrunk considerably. In some areas of the United States and Canada, companies are even incorporating this reality into their capital investment strategies. They’re looking for machinery that requires less service because there are few maintenance technicians on the market. And these companies certainly don’t want the maintenance personnel they do have going elsewhere due to fatigue or chronic stress. (If company A has out-of-control maintenance issues and company B does not—and the companies otherwise offer the same benefits—whom do you think a maintenance technician will opt to work for?)
Conveyor reliability has also risen in importance because so many of these systems have failed to perform well in high-volume biomass applications. While we could mention several infamous failures of pellet plants related to conveyor trouble, a better example may come from one of our customers. Our customer purchased conveyors from both our company and a competitor. Upon startup, the competitor’s conveyors immediately experienced issues. As of today, months later, the problems still haven’t been resolved. Due to the issues, the plant has experienced poor uptime and a loss of millions of dollars in revenue. (Our competitors built some mighty expensive machines!)
The lesson is constantly playing out across the biomass industry. As companies build more high-volume operations, more professionals learn the hard way that some conveyors don’t perform well with biomass, and some conveyor manufacturers don’t design their machines to the same standards as others. And these conveyors’ poor performance affects companies’ bottom lines.
Reliability is one of the challenges that inspired our owner to design the original SMART Conveyor™. He’d worked in the wood-processing industry for decades and knew he could build something better than the conveyors on the market.
His initial efforts have produced what is now the most reliable chain conveyor on the market, a status our owner and the engineering team he’s gathered have achieved through intentional design decisions. A few of the ways they’ve ensured SMART Conveyors™ perform reliably include:
- Adequate safety factors. We base the selection of a conveyor model for a specific application based on the volumetric requirements and the load on the chain—with safety factors to compensate for variations of which we may not be aware. If we see that the chains are near or past their rated load capacities, we choose a model with more robust chains. We will never sell a conveyor that’s undersized for the specifications our customers provide us.
- Fail points. Just as cars are designed with crumple points to protect the passengers, we designed our SMART Conveyors™ to fail in certain areas before the most important (and expensive) components get damaged. The first fail point is in the paddle finger. If something wedges underneath the finger and won’t release, the finger will break before more damage occurs to the system. The second fail point is the paddle as a whole: a larger obstruction will bend or break the paddle. Depending on the obstruction size and shape, the paddles may also roll, i.e., break where they connect to the chain. The chains and shafts are at risk only after the paddles and paddle frames have broken. (The paddle in the above photo demonstrates how these fail points work: the paddle broke, while the chains and shaft did not.)
SMART Conveyor™ Dust Control
Another area of growing concern is dust control. Two factors are driving this. The first is the labor market. As the economy has recovered from the COVID-19 pandemic, demand has rapidly outpaced the workforce. As a result, companies have struggled to find workers, especially for low-paying jobs like cleanup. Yet, controlling dust is necessary due to increasingly stringent standards for handling explosive and flammable materials—particularly biomass. These competing realities have thus driven companies to identify solutions to contain the dust better and avoid cleanup altogether.
The problem is that most conveyors used for handling biomass readily leak dust. It falls off belt conveyors on the return. It blows off open-top conveyors. It slips out holes that form in screw and drag conveyors.
Yet dust control is another area in which SMART Conveyors™ excel. They’re enclosed, so the wind can’t blow dust out of the trough. Also, unlike other manufacturers’ chain conveyors, we keep our paddles and chains off the floors and sidewalls, which reduces wear. As a result, the structural components of our conveyors last far longer than competitors’ systems. We virtually never have customers request replacements for top or bottom panels, though we suggest they have a few spares on hand for an emergency. Because of this, our conveyors don’t form leaks like other systems. (In the rare occasions where leaks have formed, the customer overloaded the conveyors.)
SMART Conveyor™ Safety
The final trait that increasingly concerns conveyor buyers is safety. We’ve already mentioned that the standards for dust control have tightened over the past few years. Standards in other areas have escalated, as well. The National Fire Protection Agency (NFPA®) not only requires conveyors handling explosive wood dust to contain it but also to:
- Be equipped with explosion suppression or relieve devices
- Be equipped with fire suppression devices (if personnel cannot fight the fire safely or effectively by hand)
- Be equipped with sensors to detect plugs or zero-speed situations
- Be able to withstand pressures under the suppression devices’ ratings without failing structurally
- Be able to divert material from the processing stream in the event of a fire or explosion
- Be designed with a direct-drive motor
There are other requirements, too, but suffice it to say, many conveyors on the market do not comply with these standards. Dust escapes too easily, the conveyors cannot divert material, or the conveyors don’t come with the required suppression devices.
Again, SMART Conveyors™ perform well in this regard. Besides containing dust, SMART Conveyors™ are available with or come standard with components to meet all the NFPA®’s requirements. They’re also inherently safer than others because they have no external pinch points. There are no pulleys to work around, either. And neither are there open chains underneath the machine.
We’ve highlighted four areas in which we’ve witnessed a growing priority in the wood-product industry, but we know, too, that every mill has its list of what’s important and not. We’re confident, though, that SMART Conveyors™ will tick most, if not all, the boxes on your list. If you’re looking at a conveyor project, contact us. We aim to understand what’s important to you so we can provide the best bulk-handling system possible.