Pulp and Paper Industry Optimizing Chemical Recovery in Pulp Mills with online spectroscopy (NIR) Benefi ts of online monitoring in the pulping process 02 In a pulp mill, chemical recovery is a key process as it does not only allow the reuse of chemicals but also provides utilities (steam, power) throughout the pulping process. Optimizing this process can lead to signifi cant cost reductions and product quality improvements. This can be realized by monitoring in real-time the composition of the white and green liquors. Alkali determination in white and green liquors Traditionally titration (ABC Tests) has been the method of During Kraft pulping, the precise and continuous analysis choice for online/atline monitoring of pulping liquors to of white and green liquors from the recovery boiler to ensure pulp quality. Despite some evident benefits of the digester is of utmost importance to guarantee the wet chemistry to differentiate the three primary highest chemical recovery efficiency. The proper chemicals, faster, reagentless, and maintenance - free optimization of the liquors’ composition reduces chemical instrumentation is needed to meet the high demand. waste, lime usage, and maintenance, while increasing Near-Infrared spectroscopy (NIRS) guarantees process product quality and increasing company profits. control in real-time and seamless integration to all industrial environments. Wood Digester Pulp & Black Liquor Wh W i h t i e te Liquor Liquor Water Pulp Washers Caustic Lime Kiln Weak Plant Black Liquor Evaporators Green Liquor Sampling Points Strong Black Steam Additional liquor measurements Liquor Recovery Boiler Benefits of online NIRS in a pulp mill $ Greater and faster return on investment SAVE MONEY • Cost reductions (lime purchase, utilities, maintenance) by process optimization • No chemicals and reagents required, greatly reducing operational costs Improved product quality and manufacturing efficiency LITY CONTROL A • Increase the degree of reduction efficiency and causticizing efficiency U Q • Improves production rate (continuous and optimized feed to the digester) APPROVED Save analysis time, faster time to market • Multiple parameters are simultaneously determined every 30 seconds • Optimized operation, real-time monitoring leads to an increased throughput of product quality Metrohm Process NIRS for Alkali determination in liquors NIRS is well-established across many industries as a versatile, fast, and nondestructive analytical 03 technology. Pulping liquors can be successfully subjected to Near-Infrared (NIR) analysis despite their complex and harsh composition. Real-time optimization of the liquor quality enables Online NIRS can complement titration-based improved liquor reutilization, reduced equipment methodologies offering reagenteless automated maintenance, and increased recovery effi ciency and measurements with no need to carry samples to the causticizing effi ciency. In pulp mills, alkali determination laboratory and easy 24/7 operation. Results are directly is commonly made through ABC-tests either in the sent to the plant’s PLC or DCS every 30 seconds. laboratory (every hour) or online (every 30 min). Complementing laboratory titration Complementing online titration Back to process Back to process Sampling Point for Sampling Online Points Titration up to 1km up to 1km Laboratory Analysis Sample from Green liquor White liquor process sample sample To waste Offl ine Titration - Online NIR  Online Titration - Online NIR Metrohm NIR Process Analyzer can measure up to 9 Online titrators have a sample stream coming to the independent sampling points. The ideal online instrument. To implement Metrohm NIR Process implementation consists of 2 circulating loops Analyzer, a flow-through cell is placed on the sample connected to flow-through cells, one for each liquor stream. White and green liquors are flowed through type. Each sampling point can be a hundred of meters sequentially after cleaning intervals. An identification apart. The nondestructive character of NIRS allows the step is being implemented at this stage to allow liquor samples subjected to analysis to be sent back to type determination. This step is crucial for simplifying process. alkali determination at the correct process stages. Alkali determination by NIRS Quantification Parameters: Accuracy Online NIR solutions gradually have gained ground White Liquor Green Liquor against the dominant wet chemical analytical strategies (g/L; ±) (g/L; ±) in the pulp and paper industry. Currently, ABC-Tests are widely used to determine Alkali (active (AA), effective AA 0,5 0,6 (EA), and total titratable (TTA)) in white and green liquors, EA 0,4 0,3 from which sodium carbonate (Na CO ), sodium sulfide TTA 0,5 0,4 2 3 (Na S), causticizing efficiency (CE) and recovery efficiency 2 Na CO 0,6 0,5 2 3 (RE) are derived. Online monitoring with NIR can go a Na S 1 1 step beyond and provide fast, precise, and reliable results 2 allowing a real-time control of the chemical recovery process. NIRS solutions in papermaking Related documents Metrohm Process Analytics offers two NIRS lines: XDS • For more details about our solutions in the pulp and and PRO. The NIRS PRO can be confi gured for contact paper industry check our brochure: 8.000.5221 - measurements (for moisture in wood chips for instance), Paper and pulp industry – reliable online, inline, while the XDS can handle up to 9 independent measuring and atline analyzers for paper manufacturing. points. These analyzers come with a wide portfolio of fi ber optics and probes ready to handle any sample. Here • For more details about our process analyzers, are some additional parameters that our NIRS Process check out our brochure: 8.000.5175 - Industrial Analyzers can measure: Process Analyzers – Multi-purpose analysis systems for online, inline, and atline applications • Kappa number • Moisture • Lignin content • Resin • Contact your local Metrohm Process Analytics • Kraft pulp yield • Brightness organization for more details about alkali determination • Tal oil • Wood species with NIR: AW NIR NL10-2052-062019 - • Coatings • Hardwood/Softwood ratio Determination of Alkali in Kraft liquors by process • Component analysis (clay, TiO , fi llers, ash, etc.) 2 NIRS in Pulp and Paper industry www.metrohm.com witzerland G, CH-9100 Herisau S ohm A witzerland at Metr a, printed in Seir 12 err fi cations ea F Subject to modi Layout by Andr 8.000.5330EN – 2019-