Several changes and additions were made to increase the production capacity from 80,000 to 105,000 tonnes/year. These included reconfiguring the yard to facili- tate material handling, adding a chipper, upgrading and adding pelletizers, adding a new cooling system, and upgrading the computer operating system. The change from using bark as the main fibre source to using a variety of materials involved a bit of learning on the material handling side, says O’Connor. At first, they tried chipping or grinding the logs into large storage piles as the wood arrived at the mill. Now, the logs are stored whole, segregated by species. This reduces the must be blended with whitewood to reduce the ash content. “We use different reci- pes or blends of materials, depending on the required production results,” explains O’Connor. But the available supply of ma- terials doesn’t dictate what they produce. “We buy in accordance to our production; whatever the pellet market wants is what we’ll buy for raw material.” RECIPES FOR SUCCESS Enligna expanded its production in the fall of 2009, with the help of a $2.5-million loan through Nova Scotia Business Inc. chance of spontaneous combustion fires starting in chip piles and helps minimize moisture accumulation due to snow, ice, and rain. And keeping the species, and the deadwood, segregated helps in the manu- facturing process by allowing better knowl- edge of the fibre’s moisture content. “You can make pellets out of anything, you’ve just got to know what you’re making them out of,” says O’Connor. Logs are chipped about a day ahead of the fibre’s use and according to the type of pellets being made. To keep up with pro- duction, the company recently purchased a CBI Magnum Force 6400 horizontal grinder with chipper rotor, along with a Liebherr 904 material handler to feed the machine. The chipper rotor has had major benefits, says Andy Wright, vice-president operations, who oversees the day-to-day functioning of the facility. It produces quarter-inch (about 6-mm) pieces that are cut across the grain, facilitating the drying process, as well as the fibre’s pulverization further down the line. Bark from the three Valon Kone 550 ring debarkers at the pulp chipping op- eration arrives by conveyor from across the road, and two Volvo L90D front-end load- ers move that and the chipped fibre to two infeed bins. One bin is fed with bark to fuel the 70-million-BTU GTS Energy bio- mass furnace and high-pressure boiler for drying the pellet material. The other is fed bucket-loads of the various fibre types in specific proportions to make industrial or premium pellets. Here, the loader op- erators play a key role in maintaining the proper blend to produce consistent pellets, says Wright. Fibre fed into the pellet production line first passes through a Jeffrey 66WB green hog, which reduces the particle size. The material is then conveyed to an M-E-C triple-pass dryer, where the moisture content is reduced from 35–65% to 6–8%. From there, it passes through an Oliver destoner, which removes heavy knots and rocks, be- fore going to 500-hp Andritz Sprout-Mata- dor hammermills to be pulverized. Because the raw fibre consists of bark, and because of harvesting conditions in the forest, de- stoning is especially critical, as the crew found out early on. Stones that get into the hammermills can cause sparks during the hammering process, creating a serious fire hazard. “We didn’t install the destoner ini- tially, and we had trouble with sparks in the hammermills due to the stones. We quickly realized that we needed a destoning process and that we had to be more particular in raw material procurement,“ says Wright. 18 CanadianBIOMASS MARCH/APRIL 2010
Canadian Biomass March/April 2010: Page 18
