Briquettes on Fire

Treena Hein
October 15, 2010
Written by Treena Hein
Look out pellets – briquettes are stealing some of your limelight. As government and private industry explore renewable ways to produce heat and electricity, briquettes are being touted as having important advantages over pellets, such as greater feedstock flexibility and lower production costs. Briquettes have similar heat and density values to pellets and are made in two formats: smaller pucks in a range of diameters, and larger cylindrical or square firelogs.

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Briquettes are popular in Sweden, where they’re used industrially to feed district heating systems.
Photo: Briquetting Systems

 
As with biogas digesters, briquette making has had a long history in Europe, and that’s helping to speed its adoption in North America. Here and in Europe, both pellets and briquettes are being used in home heating, industrial boilers, and district heating and co-generation plants.

Promoters of briquettes point to their many benefits, such as not requiring materials as finely ground as those needed for pelletization. “Particulate size for briquettes can be larger than for pellets – up to 15 mm – thus requiring less pre-grinding energy,” says Wayne Winkler, president of Vancouver, British Columbia-based Briquetting Systems Inc., the Canadian distributor of Denmark-based CF Nielsen briquetting machines. “Manufacture requires significantly less power consumption, both from a grinding and a pressing view.”

Winkler says that pelletizing fines requires large power-consuming hammermills (typically with outputs of 100 hp/tonne) as well as expensive after-coolers, dust collection systems, and drum-type drying systems, which “are usually fired and have their own fire hazard issues. All this increases both the cost and time to make pellets in comparison to briquettes.” In addition, Winkler says that using dust fines to make pellets is to risk explosions, fires, and respiratory problems.

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Briquettes can be made of a variety of materials and come in various sizes.
Photo: Briquetting Systems

 
Compared to pellet making, briquette manufacturing also has lower repair and maintenance costs and faster start-up times. “Die replacement in briquetters is a fraction of the pellet die cost,” Winkler notes. “Roll press briquetting is the main technology that has been used for decades to compact high capacities of coal fines into briquetted coal shapes. Wood fuel puck production in most cases will not require expensive hammermilling in production.”

Briquettes can also be made from a wider variety of materials that can have much higher moisture contents – up to 15% – compared to those required to make pellets. “A wide array of feedstocks, some that are not pelletable, can be briquetted, including wood, agricultural residue, paper, and mixtures of feedstocks,” says Winkler. Another option for briquetting is torrefied wood, which is green wood that has been reduced to char through mild pyrolysis using high temperatures in a closed environment with little or no oxygen. “Torrefied wood can be ground with coal ball mill pulverizers, and it’s waterproof, so it can be stored outside,” says Winkler. “It also has a higher heat value than wood, but most torrefaction technology is still in the pilot stage.” Some pellet producers have also been considering and testing torrefaction.

Briquettes are at least as easy to handle as pellets in terms of loading and unloading shipping containers at ports. Winkler says drive-through tipping devices have been developed that allow briquettes to be quickly bulk-loaded into containers. They can also be loaded in super-large sacks.

James Brose, president of Kanviromental Corp., a briquetting machine manufacturer in Elmira, Ontario, notes, “It’s also important and very relevant to appreciate the fact that pellets have 15 times the surface area per similar weight than briquettes do. Moisture uptake not only kills the BTU values the pellets left their source with, but additionally increases content shipping weight.”

End-market uses
While residential pellet stoves have made inroads in Canada, briquettes are being used in home heating across many U.S. states. Indeed, the customers of Cleveland, Ohio-based RUF US Inc. (the North American distributor for Germany-based RUF briquetters) are producing briquettes mainly for residential heating. The rectangular (6 x 2.5 x 3-inch) briquettes can be used in any wood-burning appliance, says RUF US president Greg Tucholski, and are available to customers in many mid-U.S. states through retail outlets in bags or by bulk delivery at USD $250–350 per tonne. “Customers are using two to three tonnes a winter,” he observes. “Briquettes produce much less ash and provide a cleaner, more consistent and longer burn than wood. Customers like the convenience and cleanliness of the product and the fact that they last longer during the night than firewood.” Tucholski says the feedstock is mostly kiln-dried residuals from wood product manufacturers and sawmills. He’s sold about 50 machines so far and expects to sell 20 to 30 more in the next 12 months.

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Briquetting systems are modular and can be added to match output requirements. These presses are fed by overhead conveyors and discharge gates, and the discharge cooling lines also act as exit conveyors. The force of the press action moves the briquettes down the cooling line to a collection point. The cooling lines can have bends in them to configure to a single collection point in a warehouse, container, truck, or bagging line.
Photo: Briquetting Systems

 
In Mont Joli, Quebec, Bois BSL Énergie Inc. has been producing “SmartLogs” since 2006 for home heating, which the company claims produce almost 35% more heat than firewood. “Our sales have increased from 2006 to 2009, but are stable since then, having reached a maximum level in a saturated market,” says Jacynthe Rodrigue, Bois BSL energy division sales manager. The company lists Rona, Kent, Millwork Home Centres, and other stores in Quebec and Ontario – along with one U.S. distributor – as sales outlets.

Bois BSL uses an in-house CF Nielsen briquetter to process hardwood sawdust from its flooring manufacturing operation. CF Nielsen briquetters are also available in two other versions – containerized (semi-portable) and a large silo format with feedstock fed via air-handling or conveyor to an upper floor with sweep-auger feeding to presses on a lower floor. “Both these formats negate the need for a building,” Winkler notes.

Other companies, such as Brenlo Custom Wood Mouldings in Mississauga, Ontario, are marketing briquettes to greenhouse operators. Brenlo started making pucks using a CF Nielsen machine in August 2009. “We have multiple greenhouse customers, but with natural gas prices decreasing, it’s been a challenge on the return on investment side,” says Overton Smith, Brenlo’s head of research and development and commercial development. “We’re managing our prices based on customer demand.” Smith expects that cost return on the machine will be reached in about two more years, but is optimistic about demand. “We expect that natural gas prices will go up again,” he notes. “Our briquettes are very popular. They produce very high BTUs – over 8100 per pound – because they’re made from kiln-dried wood byproduct, and produce almost no ash.”

However, the natural gas price drop has meant the greenhouse market has completely dried up for Sauder Moulding & Millwork in Ferndale, Washington. Its CF Neilson briquetter is currently idle. “We sold a container about five months ago to a greenhouse,” says spokesperson Ryan Hammer, “but we’re now back to selling our (hemlock) sawdust directly to local farms.”

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Firelogs made at Bois BSL in Mont Joli, Quebec, are used mainly in home heating appliances.
Photo: Briquetting Systems
 
The Quatsino First Nation Economic Development Corporation (QFNEDC) in Coal Harbour on Vancouver Island, British Columbia, is planning to serve the greenhouse industry as well as feed boiler systems in commercial and industrial buildings. It will be making briquette pucks and some “niche market” firelogs with byproduct from its cedar shake operation, which uses hemlock, red cedar, red alder, and balsam fir. “We’re planning to start within six months, pending funding for the project,” says QFNEDC general manager David Schmidt. The project also involves consultants and other specialists. Quatsino decided on briquettes instead of pellets because they’re “cost effective and the market is better,” says Schmidt. “The competition in the pellet market is fierce and, without going overseas, hard to get into.” He adds that hemlock doesn’t make very good pellets.

Some wood product manufacturers are briquetting residuals to feed their own boilers. “There’s a misconception that briquettes cannot be broken up to fit in boilers designed for dust or pellets, but it can be done easily,” says Irvon Weber, Kanviromental’s chief technology officer. Winkler notes that CF Nielsen is developing a puck quartering system for boiler use. At West Fraser’s Westpine medium-density fibreboard plant in Quesnel, British Columbia, they “occasionally briquette sander dust when too much has built up,” says plant manager Dave Berg. “We burn the dust in our thermal oil system, but when there’s too much for us to handle, we briquette it and truck it to our Quesnel pulp mill for use in their boiler. It’s much easier to transport briquettes than dust.” Berg figures cost-return was reached about a year after getting the CF Nielsen briquetter two years ago, and adds that there’s been recent talk of purchasing briquetters at other West Fraser operations.

Power generation abroad
While the short-term export outlook to Europe for both pellets and briquettes has recently taken a hit, mostly due to the Euro’s plunge in value, several companies are actively shipping or making large-scale plans to ship densified fuel overseas for power generation.

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  Kanviromental’s briquetter, called the BioKrush, comes in one, five, and eight tonne/hour capacities.
Photos: Kanviromental

The long-term market potential is huge. A recent study by German energy consultant ecoprog and the Fraunhofer Umsicht research institute predicts that new wood-fired power plants in the United Kingdom and France will see biomass capacity in those countries grow 50% by 2013. New biomass power plants have also been built recently in Scandinavia, Germany, and Austria. Scandinavian countries will continue to have the biggest use of biomass, due to their relatively large timber resources in comparison to other European countries. A further 130 plants are being built all over Europe and the United Kingdom, which will bring the expected number of plants to 1050 and biomass generating capacity to 10,000 MW by 2013.

Carolina Pacific in Charleston, South Carolina, shipped its first load of briquettes to Sweden in March. President John Kern says they will ship another 50,000 tonnes this year and 100,000 to 250,000 tonnes next year. “Germany, Belgium, Netherlands, Denmark, and other Scandinavian countries are good markets,” he says. “They want to build plants and make long-term agreements.” England, however, is another story. Kern notes that the failure of that country’s energy subsidy regime has made it very difficult to predict prices. “Natural gas cost has gone down, and some power plants have switched to that from coal, which has gone up in price,” he notes. “They won’t sign long-term contracts with fixed prices (for biomass).”

Kern also observes that there’s only a small market for home heating in the eastern U.S. states because of the mild winters, and that coal is “still king” for power generation there. Carolina Pacific’s trademarked ROCette briquettes are made using a proprietary process that involves Di Più (Italy) and CF Nielsen equipment. “It’s an impact press, rather than a die, with continuous extrusion,” says Kern. ROCettes deliver over 8,000 BTU/pound, and are made from a combination of logged pine and residuals from local furniture and moulding operations.

Not everyone is shipping briquettes. RWE Innogy, the renewable energy arm of German-based energy giant RWE, plans to ship pellets to Europe from a €20-million plant they are building in Georgia, USA, in partnership with Sweden’s BMC Management AB. By 2011, the plant will produce 750,000 tonnes/year of pellets for use in European biomass power and co-generation coal plants. When asked why they chose pellets, RWE spokesperson Heinz Vinkenflügel said, “The experiences of co-firing biomass in European power stations are based on using pellets. Pellets are the most traded biomass in the world and … at present, there are not enough long-term experiences with briquettes to prove the … theoretical advantages."

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These small briquettes are made from a mixture of paper sludge and wood chips.
Photos: Kanviromental
 
Pacific Briquetters Inc. in Mission, British Columbia, (a subsidiary of Vancouver-based Carbon Friendly Solutions Inc.) would like to be producing briquettes for U.S. and European power plants, but has put plans for that on hold for now. Carbon Friendly Solutions CEO Mike Young says, “We had been in discussions with energy companies in the Scandinavian region to purchase briquettes in the €125/tonne range. However, with the sudden drop in the euro, there is almost a 30% decline in profit, making it no longer profitable. Basically, our cost to produce briquettes is approximately CAD $90/tonne FOB (free on board) our mill. Shipping costs overseas are in the CAD $50 to 60/tonne range, so you can see the margins were already going to be tight.” Young says they’d ideally like to sell and ship within North America, “but to the best of my knowledge, the market is not there yet.” In the meantime, Pacific Briquetters is going forward with developing its wood waste and recycling facility in Mission, and Young says they can easily move into briquette production as demand increases.  

Domestic power
For North American utilities to effectively use briquettes, Winkler advises them to investigate the best technical features of bio-fired European plants and tweak the design to suit local markets. “This could involve co-firing with biomass and natural gas, which has already been done in Sweden,” he says. “Demand for fuel briquettes is large, as there are more than 600 coal-fired plants in North America, many in the 600-MW range, which equates to approximately one million tons/year of coal per plant. If 5–10% of it is exchanged for biomass fuels, it equates to millions of tons of required biomass. Coal-fired power plants can use their own stationary grinders to grind briquettes.”

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CF Nielson briquetters are available in stand-alone containers, obviating the need for a new building or building extension.
Photo: Briquetting Systems

 
Brose says it’s a misconception that briquettes are too big to use in power plants. “The coal must be ground up anyway, so briquettes are fine,” he notes. Since drying is needed for briquetting however, Brose notes that combined heat and power systems that have been developed in Europe are a smart move. “Electricity is produced from the briquettes and the waste heat dries the biomass that goes into the briquettes, which eases costs significantly,” he notes.

Kanviromental’s BioKrush briquetter was developed using the staff’s long expertise in densifying scrap metal from the automotive industry and is designed for industrial settings where large throughput is required. “There are already small-throughput European machines available, so we’ve focused on what we call ‘central briquetting,’” says Brose. “This means one of our units would briquette feedstocks like sawdust and chips, purpose-grown crops, or paper waste leftover from recycling operations at (capacities of) one, five, and eight tonnes/hour.” The company has some machines in stock but plans to produce them on a made-to-order basis. Director of sales Gary Cruickshank says the company may choose to find partners to jump-start electricity production from briquettes, but that the company’s focus is briquetter manufacturing. “It’s a relatively new industry to Canada,” he notes, “but Ontario Power Generation and others are very interested.”

To supply a local co-fired coal plant as well as local boilers, Ernst Conservation Seeds in Meadville, Pennsylvania, expects to have a commercial briquetting operation (pucks and firelogs made from switchgrass) up and running by spring 2011. “It will include storage for the switchgrass, a dehydration system that will use waste from our feed mill, and a pellet mill to produce pellets for anything that doesn’t have an eight-inch auger,” says Ernst biomass manager Dan Arnett. Since purchasing a CF Nielsen briquetter in February 2008, the company has been running tests at a coal plant, a greenhouse, and a school with a biomass boiler.

As someone who has watched the densified fuel market closely for a long time – and is admittedly enthusiastic about briquettes – Winkler still remains guarded. Until Canada and the United States have a carbon tax and regulatory framework in place, he says, expansion of the densified biofuel market will remain difficult, whether that involves pellets or briquettes. “In terms of export, we’re at the mercy of low currency exchange rates, fluctuating shipping rates, as well as European utility buyers working together to set prices,” he concludes. “At the same time, we must fight the perception here in North America that fossil fuels are cheap, when in reality they are not. Even at the best of times, margins are narrow in biofuels, but we must not allow other countries to commandeer our future.”

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