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A-RECOVERY+ CHEMICAL RECOVERY SOLUTION A-Recovery+ Chemical TABLE of CONTENTS Recovery Solution: New Opportunities in Kraft Mills

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A-RECOVERY+ CHEMICAL RECOVERY SOLUTION A-Recovery+ Chemical TABLE of CONTENTS Recovery Solution: New Opportunities in Kraft Mills SEE THE CHEMICAL CYCLE IN A NEW LIGHT A-RECOVERY+ CHEMICAL RECOVERY SOLUTION A-Recovery+ chemical TABLE OF CONTENTS recovery solution: new opportunities in kraft mills A-RECOVERY+ CHEMICAL SULFURIC ACID With the goal of operating chemical recovery systems in a way that is as effi- RECOVERY SOLUTION PRODUCTION cient and and environmentally sound as possible, while minimizing capital and The next generation solution Production of concentrated operating expenses, A-Recovery+ chemical recovery solutions from ANDRITZ for the chemical recovery commercial-grade sulfuric cycle of pulp mills. acid in the mill can lead to offer new opportunities for kraft mills. significant savings. Over the years, chemical recovery loops have been “closed” to reduce emissions METHANOL LIGNIN RECOVERY and effluents – and to increase recov- PURIFICATION Production of high- ery efficiency. These closures some- Raw methanol is purified to a quality lignin on site can times resulted in an overabundance of merchantable bio-methanol. debottleneck a recovery certain chemicals in the chemical cycle boiler and reduce the cost and sometimes created side streams or of purchased fossil fuels or waste streams that were either disposed generate additional revenue of or ignored. by selling bioproducts. BENEFITS OF A-RECOVERY+ SOLUTIONS • Environmental and economic savings • Further closure of chemical recovery loops • Management and control of sodium/sulfur (Na/S) balance • Generation of key chemicals avoids purchasing costs • Additional opportunities for revenue generation • Removes obstacles to fossil-free operation 2 3 SEEING CHEMICAL RECOVERY IN A NEW LIGHT ANDRITZ has taken a fresh look at chemical recovery and developed technical solutions called “A-Recovery+”. This shines a new light by further closing the chemical cycle and converting side streams. It is a tailored solution to optimize the Na/S balance in a mill and generate economic value from the side streams in a kraft pulp mill by: 1 Purifying raw methanol to commercial-quality bio-methanol 2 Producing commercial-quality sulfuric acid on site from concentrated non- condensable gases 3 Recovering high-quality lignin from black liquor Current state of chemical recovery 3 2 1 A-Recovery+ chemical recovery solution – additional chemical cycles for cost optimization and added revenues 4 5 1 PURIFYING RAW METHANOL TO 2 PRODUCING COMMERCIAL QUALITY SULFURIC COMMERCIAL-QUALITY BIO-METHANOL BIO-METHANOL PLANT IN SWEDEN ACID ON SITE FROM CONCENTRATED Raw methanol in the kraft process is often NON-CONDENSABLE GASES used as an alternative fuel (combusted in ANDRITZ recently received an order from Södra, Softwood mills often have a sulfur surplus due to addi- the recovery boiler for example). Methanol Sweden, to supply a bio-methanol purification tional sulfur inputs such as a tall oil plant. This requires is usually the last fossil-based chemical in a plant for the Mönsterås pulp mill. When com- the landfilling or dumping of large amounts of recovery kraft mill, prohibiting the establishment of a pleted, the plant will produce 5,000 tons of boiler fly ash to control the sulfidity of the white liquor. completely fossil-free mill. bio-methanol from renewable raw materials per year. The bio-methanol will be in compliance In addition to the potential environmental impact and The A-Recovery+ chemical recovery solution with IMPCA methanol quality reference specifi- costs associated with ash dumping, there is also a for methanol purification uses a patented, cations for merchantable methanol. loss of valuable sodium, which must be replaced in the mineral oil-based extraction process. Puri- cooking process by purchasing NaOH. A technically fied methanol can be used as a low-NOx The current target of the EU is to have 10% of the and economically attractive alternative is the integra- fuel for combustion in the recovery boiler or transport fuel coming from renewable sources, tion of an A-Recovery+ sulfuric acid plant to produce lime kiln, or as a support fuel in the sulfuric such as biofuels, by 2020. Södra has announced concentrated commercial-quality H2SO4 on site from acid plant. Commercial-grade bio-metha- its own strategy to be totally fossil-free by 2030. concentrated non-condensable gases (CNCG). This nol can also be sold for revenue or used in commercial-grade production is critical, especially for ClO2 generation if performed on site. demanding applications such as ClO2 generation. WSA - Wet gas sulfuric acid A-Recovery+ uses the wet-gas sulfuric acid (WSA) process There are over 150 references for the WSA technol- developed by Haldor Topsoe, which employs catalytic ogy operating worldwide on a variety of sulfurous gas conversion and condensation. The sulfuric acid produced streams as well as spent acid. is commercial-grade since the liquefaction of H2SO4 is executed at 100% condensation. All sulfuric acid that a mill Hardwood mills can also benefit greatly from the inter- requires can be produced on site if the CNCG is co-com- nal production of H2SO4. The benefit comes from the busted with elemental sulfur in the WSA plant. The sul- re-arrangement of make-up chemicals. For example, fur amount in CNCG can be adjusted to result in a bet- make-up NaOH to chemical cycle can be replaced with ter balance by extracting more sulfur from black liquor inexpensive Na2SO4 when the amount of sulfur input is with an ANDRITZ liquor heat-treatment (LHT) system. decreased by the internal production of sulfuric acid. 3 RECOVERING HIGH-QUALITY LIGNIN FROM BLACK LIQUOR When the quality of lignin recovered from black liquor is sufficiently high, it can be used either to replace fossil fuels in the lime kiln or to generate additional revenue by selling it externally as a raw material for advanced bioproducts. The challenge in making lignin recovery technology cost-competitive has been to reduce the cost associ- ated with removing excess sulfur that is introduced in the chemical recovery cycle with the addition of sulfuric acid used in the process. This challenge can now be resolved by integration of a WSA plant and lignin recovery. The A-Recovery+ lignin recovery process entails precipitat- ing lignin from the black liquor with carbon dioxide, filtering the precipitated lignin, subjecting it to acid washing, and then drying it. Sulfuric acid is used for the acid washing. Bio-methanol purification plant A-lignin technology 6 7 NEXT-GENERATION CHEMICAL RECOVERY FROM ANDRITZ Chemical recovery is an essential part of pulp production and ANDRITZ is a dependable technology and service partner for chemical recovery. A key competence is our ability to innovate. Our specialists are skilled in helping you install, upgrade, and renew the essential components of your chemical recovery system to improve performance and reliability with value-added enhancements. We are passionate about engineering success for our customers by innovating solutions that not only recover chemicals and generate power efficiently, but do this in a safe, reliable, and environmentally sound way – at the lowest cost of ownership. If this is the kind of success you desire for your mill, we can help you engineer it. FINLAND JAPAN ANDRITZ Oy ANDRITZ K.K. p: +358 204 50 555 p: +81 3 3536 9700 BRAZIL AUSTRIA ANDRITZ Brazil Ltda. ANDRITZ AG p: +55 41 2103 7601 p: +43 316 6902 0 UNITED STATES OF AMERICA CHINA ANDRITZ Inc. ANDRITZ (China) Ltd. p: +1 770 640 2500 p: +86 757 8202 9222 ANDRITZ.COM All data, information, statements, photographs and graphic illustrations in this leaflet are without any obligation and raise no liabilities to or form part of any sales contracts of ANDRITZ AG or any affiliates for equipment and/or systems referred to herein. © ANDRITZ AG 2018. All rights reserved. No part of this copyrighted work may be reproduced, modified or distributed in any form or by any means, or stored in any database or retrieval system, without the prior written permission of ANDRITZ AG or its affiliates. Any such unauthorized use for any purpose is a violation of the relevant copyright laws. ANDRITZ AG, Stattegger Strasse 18, 8045 Graz, Austria. Due to legal considerations, we must inform you that ANDRITZ AG processes your data for the purposes of informing you about the ANDRITZ GROUP and its activities. Find out more details about our data privacy declaration and your rights under the data protection legislation on our website: andritz.com/privacy. A-Recovery+ brochure / 10.2018 EN .
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