The flue gases generated in the com-bustion chamber go through a set of ductwork to a Rentech-designed boiler that heats the water up and runs the steam through superheated coils. The combus-tion chamber is designed to use upwards of 8,000 tons of biomass an hour. “It’s a 50,000 lb/hr boiler running be-tween 750 and 800 psi of super-heated steam,” Saulnier says. Some of the excess heat from the flue gases passes through an economizer that pre-heats the water going into the boiler. two-stage turbine, which turns at 1,800 rpm for a Hyundai-designed generator producing 3.1 megawatts of electricity. “The turbine can ramp up in about 30 seconds,” Saulnier says. “Because we’re burning a wood-fired boiler we’ve actu-ally stretched it to about 200 seconds be-fore it goes up to full speed.” The boiler plant and the combustion system was a packaged system created by KMW Energy based out of London, Ont. KMW Energy was the primary equip-ment supplier for the project, supplying OPERATIONS “The increased lumber production was important for two reasons: to keep the sawmill competitive and to fuel the company’s latest investment...” “The purpose of the economizer is so you don’t need as much energy to heat the water back up,” Saulnier says. “It’s common in boiler plants. It’s a way for us to utilize as much of the heat as possible before losing it out the stack.” When the flue gases leave the econ-omizer they then go through a cyclone separator that removes any final particu-lates that may be in the air before going out the stack. By the time the steam hits the stack it’s around 300 F and clean. After moving through the superheated coils, the steam travels to the plant’s Siemens the boiler, turbine, generator and much of the auxiliary equipment. Acadian Construction out of Moncton, N.B. were the general contractors on the project and assisted in the building of the 17,000 sq. ft. building housing the plant and oversaw the project’s construction. The company also co-ordinated the elec-trical, mechanical and other sub-trades on the project. The mechanical engi-neering company hired for the project was Crandall Engineering, while Black & McDonald and Maritime Pressure Works shared the mechanical installation duties. The plant’s day-to-day activities are over-seen by a 3rd Class power engineer panel operator and a 4th Class power engineer outside operator. “The panel operator runs everything from the control room and makes any necessary adjustments required to safely operate the plant, while the outside oper-ator walks the floor, taking readings, per-forming preventative maintenance, and making field adjustments when necessary while corresponding with the panel op-erator,” Saulnier says. “It’s a second-class power plant and we’re fortunate enough to have a first-class chief engineer retired from Nova Scotia Power. Even though it’s a small power plant we tried to set the control room up the same as you would see in a larger power plant.” A LONG-TERM SOLUTION With a 20-year contract to produce elec-tricity for Nova Scotia Power, Hefler Quality Lumber has created a productive use for its sawmill residuals and a second-ary income stream to help the company stay competitive well into the future. “With all the challenges of having a sawmill in a very competitive market-place, sawmills need to start thinking outside the box to find other ways to gen-erate revenue in order to survive, which in turn creates long-term employment,” Saulnier says. “In our case, our solution was to produce 3.1 megawatts of power for Nova Scotians.” • UNCONGESTED SHORT-SEA-SHIPPING BULK DEEPWATER UNLIMITED STEVEDORING YEAR-ROUND-FACILITY INFRASTRUCTURE FLEXIBILITY BARGE ROLL-ON-ROLL-OFF INTERMODAL WAREHOUSING COMPETITIVE COMMUNITY EASTERN-CANADA FLEXIBILITY TRANS-SHIPMENT BELLEDUNE UNCONGESTED SHORT-SEA-SHIPPING BULK DEEPWATER www. port of belledune .ca CBM_MarApr16_Belledune_CSA.indd 1 Canadian BIOMASS 2016-03-08 9:08 AM 21
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