Transforming efficiency and safety through a lower furnace rebuild
Oct 22, 2024
By integrating Valmet’s technical expertise, our focus on sustainability, and the contractor’s precision, we achieved substantial improvements in efficiency, safety, and performance, and cut our boiler wash time nearly in half.” - Mason Rowat, Area Supervisor – Recovery & Steam Plant Operations at HARMAC
Summary
Mauricio Harger, General Director for CMPC in Brazil
Location
HARMAC, a Northern Bleach Softwood Kraft pulp mill in Nanaimo, BC, Canada.
Customer challenge
The mill faced significant challenges with its aging boiler system. The older boiler system, paired with outdated air systems, led to operational inefficiencies and safety concerns. An audit revealed the need to modernize the lower furnace from a sloped floor to a decanting style, update the primary, secondary, and tertiary air systems, and install a new tertiary air fan. These upgrades were crucial for drastically improving boiler performance and addressing issues like insufficient primary air velocities.
Solution
Air System Replacement: Upgraded primary, secondary, and tertiary air systems for better air distribution and combustion efficiency.
Boiler Performance: Replaced outdated rodders and smelt system to maintain optimal operation.
Smelt Flow Improvement: Installed new spouts to enhance smelt flow and added agitators to improve chemical recovery.
Real-time Monitoring: Introduced a bed camera for continuous monitoring to maintain ideal combustion conditions.
Advanced Smelt Technology: Integrated spout plug technology and shatter jets to improve smelt shattering, reduce explosion risk, minimize noise, and decrease deposit buildup.
Comprehensive Support: Valmet provided remote and on-site support, covering planning, execution, and post-installation services for smooth equipment installation.
Results
Improved Operations: The lower furnace rebuild significantly enhanced mill operations.
Enhanced Combustion Efficiency: New air systems and furnace design optimized combustion and ensured consistent spout flows.
Reduced Maintenance: Fewer maintenance needs due to improved system reliability.
Shorter Water Washing Time: Introduced a bed camera for continuous monitoring to maintain ideal combustion conditions.
High Emission Reduction Efficiency: Achieved 95% reduction efficiency with:
SO₂ levels: Below 5 ppm
CO levels: Below 300 ppm
Particulates exiting economizer: Below 9 grams
Surpassed Sustainability Targets: Met internal goals and aligned with HARMAC’s sustainability objectives.
Fewer Boiler Cleanings: Efficiency improvements led to less frequent cleanings, highlighting the system’s effectiveness.
Discover why Valmet, with over 225 years of industrial expertise, is the trusted OEM partner for comprehensive services and innovative solutions. Explore our site and download the OEM guidebook today!
