Pulp and Paper Technical Association of Canada Bleaching Committee

INTRODUCTIONS AND BUSINESS

• 80 members and guests present
  
• Cal Lum welcomed members on behalf of AlPac. We will be leaving the hotel 7am on Wednesday, returning by 3pm
  
• joint meeting with TAPPI - Per Klykken thanked the Pulp and Paper Technical Association of Canada Bleaching Committee for allowing their members to join us in our meetings
  
• sad note - the passing of Howard Rapson - see handout. June 13 memorial service. A memorial fund for P&P students has been set up in his name. Stuart Scott is formulating a letter of condolence to the family on behalf of the Bleaching Committee.
  
• Glen Black talked about Pulp and Paper Technical Association of Canada business:
  
  • 1,568 Technical Section delegates at annual meeting from a total of 14,959 attendees (vs. 1624 of 15,154 in 1996)
    
  • International Symposium on Chemistry of Wood in June/97 - there will be 96 formal presentations and >100 poster sessions
    
  • board of Pulp and Paper Technical Association of Canada discussed moving annual meeting to Vancouver - still not a proper mix of space for presenters, suppliers, conference - ExFor will be in Montreal for foreseeable future, but Vancouver situation will be monitored
    
  • 15 people in Montreal office, 2 new people - Oliver Tardiff, Denise Lemoche
    
  • Advertising campaign on TV coming to a channel near you
    
  • Pulp and Paper Technical Association of Canada have a WEB page at "www.paptac.ca"

1.0 ENVIRONMENTAL IMPACTS

Projects - Jeff Tolan

• met jointly with TAPPI Minimum Effluent committee

1.1 Pulp effluent regulations in Central Europe - Dan Davies

1.2 Environment Committee Liaison Report - Murray Walters

• Larry Tench - Stora Sweden has used ultra filtration to recycle half the caustic and all organics from an open brown stock stage in order to reduce COD so their customer can receive the "White Swan" eco label
  

1.3 Mill Experience in COD reduction - Sekar - Espanola, ON

• upgrading HW line (30 years old), high cod, so replacing brownstock washers, high efficiency washers in post O2 and bleach plant
  
• 60-70 tpd COD, expect to reduce to 45-55 tpd
  
• concerns about losses of black liquor which could cause problems downstream
  

1.4 WCB proposed chemical guidelines - Gerry Pageau

• Worker's Compensation Board will be replacing the 1979 regulations with new legislation for BC proposed for chemical and biological substances for 750 chemicals in every stack and vent - sounds similar to legislation in effect in USA - Title 5 regulations
  
• propose we get together through Paprican and share the information we know about our vents
  
• no mention in the Environmental Committee minutes - Dennis will pass info on to them
  

1.5 TAPPI Minimum Effluent Committee - Bob Packwood

• sodium sulphur balance worksheet- Larry Tench
  
• role of inorganics in preventing mill closure - Jack Fleck
  
  • barium sulphate scale with radioactive co-precipitate material
    

• review of status of bleach effluent minimization - Peter Gleadow
  
• calcium oxalate scale definition and control
  
• TAPPI Minimum Effluent Symposium - October 23-24, 1997 in San Francisco
  
  • 8 sessions + mill tour of LP Samoa
    

Proposed projects

• Paprican presentation on their closure activities - Jean Bouchard will coordinate
  
• review of ISO 14000 guidelines - of mills represented, eleven said they are pursuing certification, three are not, none expected to reduce their operating costs
  

1.6 Update on EPA Cluster Rules - Tom Kemeny

• politics seems to override the technical aspects
  
• will come out in many phases, first of 9 categories is bleached papergrade kraft
  
• promulgation Sep/97, compliance in 2000 (although no mandated date yet)
  
• EPA is not allowed to force a technology, eg. ClO2, OD, we believe 100% substitution will be adequate
  
• TCDD, TCDF and chlorinated phenolics measurements are in the bleach effluent, not in the final treated effluent - must measure both chlorination and extraction flows for every bleach plant in the mill - no combining of effluents
  
• AOX = .448 or .162 (with and without OD)
  
• COD = 45.6 or 30.4 (with and without OD) - monthly averages
  
• BOD/TSS - may not be changes
  
• BMP - best management practices - to eliminate preventable spills of black liquor, soap and turpentine - site specific
  
• incentives for compliance have become one of the major stumbling blocks causing delays
  
• air - based on maximum achievable technology - do not look as onerous as initially expected
  
  

• Tech '97 Bleaching course Sep 14-19, 1997, Norm Liebergott is the course leader, 19 speakers, lots of inquiries but no registration forms out and no advertising yet - Glen Black to take back our concerns to Pulp and Paper Technical Association of Canada, proposed to modify course to include bleaching protocol, acronyms, etc. - see Appendix for syllabus
  
• next meeting focus - Pulp Quality changes due to new bleaching technology
  
• TAPPI bleaching course was well received
  
  

3.1 Dennis Owen - not here

3.2 Doug Reid - Pulp and Paper Technical Association of Canada Oxygen Delignification Survey - copies available from authour

• determine equipment installed, operating parameters and results
  
• 10 response out of a possible 11, sent out Feb/96
  
• most are single stage, medium consistency
  
• reasons:
  
  • environment
    
  • reduce bleaching costs
    
  • mill modernization
    
  • increase production
    
  • original mill design
    

• objectives: constant outlet kappa, optimum pulp strength, constant % delignification
  
• temperature 88 to 96 C for most mills
  
• pressure 600 - 900 kPa for most mills
  
• retention time mostly 60 minutes
  
• alkali charge per kappa drop seemed to be in two different groups
  
• oxygen and MgSO4 charge fairly spread out
  
• % delignification 26% - 60% within o2 system
  
• net bleaching cost decrease 8% to 30%, average 20%
  
• lowest kappa number without strength changes 10 - 20, average 15
  
• pulp yield - 6 could not say, 2 mills saw no change, 2 mills saw increased yield if they cooked to a higher kappa number then used o2 delignification to bring down to a normal kappa, they saw 2.5%
  
• increased solids to recovery about 3.5%
  
  

3.3 Gerry Pageau - Variability in the Fibreline - see Appendix

• 17 mills, 21 bleach plants, some with digester and O2 delig info
  
• three consecutive days of the best operation in thirty previous days
  
• coefficient of variability = standard deviation / average (normalized percentage)
  
• compared 10 major parameters for all 21 bleach plants and found the COV
  
• compared one major variable to the rest to determine which are affecting others, e.g. digester rate changes affects digester level, bleach plant rate, but not final brightness
  
• front end variability seems to affect final variability, e.g. bleach rate changes results in high variability in final brightness
  
• analysis will continue, and any bleach committee member may have a copy of the spreadsheet
  

New projects

• kappa analyzer - not to evaluate brand x vs. brand y, but whether it is a useful process control tool - Don McCabe
  
• Tappi is looking into the impact of sequences on fibre quality
  
  

• recently published a glossary with the "alphabet" according to Pulp and Paper Technical Association of Canada Bleaching Committee
  
• currently involved in translating protocol and glossary into French
  
• educating members on use of protocol - Dan Davies' presentation at the annual meeting is an example - he will also present the protocol at the bleaching course in September, possibly also at the Tappi conference in San Francisco
  
• guideline for authors has protocol on last page
  
• planning on having the protocol put into the Pulp and Paper Technical Association of Canada Engineering Data sheets - Protocol Subcommittee will keep data sheets (and possibly test procedures relating to bleaching) current - request that members at large provide input on what they want to see in the Engineering Data Sheets
  
• a few minor differences between Tappi and Pulp and Paper Technical Association of Canada alphabet, but should not create confusion
  
• the protocols are different, but there seems to be room for discussion - will discuss with Tappi at San Francisco
  
  

• sessions were well attended, but attendance was down from previous two years, will push hard for better spots next year (not Friday morning)
  
• suppliers helped provide tokens of appreciation for speakers and session chairs
  
• The Future! Looking forward to the 1998 Annual Meeting
  
  • pulp quality
    
  • bleach plant optimization - survey highlighted the gross variation in bleach plant chemical usage variation - looking for mill success stories
    
  • some other smaller ideas on the back burner
    

• subcommittee is there to help organize, but need help of the entire Bleaching Committee to get good quality papers
  
• deadline for abstracts is fast approaching - JULY 25, 1997!!!
  
  

• Primary Objectives:
  
  • to explore ways the Bleaching Committee can take advantage of the Internet as a communications tool
    
  • to inform members of information, web sites, user groups, etc. on the subject of pulp bleaching
    

• over thirty members have E-mail addresses
  
• considering "cyber equivalent" of Bleaching Committee Problems and Opportunities session
  
• subcommittee will develop a list of relevant web sites
  
  

7.1 Bleaching Sequences vs. Pulp Strength - Norm Liebergott

• three people are reviewing numerous papers and will present findings at fall meeting
  

7.2 Safe Handling of Methanol

• to be presented at fall meeting
  

7.3 Safe Handling of Oxygen and Ozone -Jack Ayton

7.4 Safe Handling of Sulphuric Acid -Steve Paolone

• dramatic increase in usage, but also increase in the quality requirements
  
• largest used industrial chemical in the world
  
• primary usage in fertilizers, petrochemical, chemical and P&P industry
  
• manufactured from SO2 gas generated from burning sulphur or roasting zinc sulphide
  
• mainly sold as 93% concentration, because 93% has a very low freezing point (-30C), increasing rapidly as concentration increases
  
• specific gravity 1.8354, 15.3 lbs / USG
  
• hygroscopic, very strong affinity for moisture, so it is a very good dessicant
  
• reacts VIOLENTLY with water, especially when water added to acid - always ADD ACID TO WATER
  
• non flammable, but may generate hydrogen gas in the presence of hydrogen, so critical to check atmosphere in confined spaces, piping, etc.
  
• low corrosion at 93%, but very high corrosion rate at 84%, up to 10 times as corrosive - important to keep moisture out of rail cars or will create a weak layer of acid that can destroy the lining in the rail car
  
• pad air should have a dew point of -40C
  
• mild steel okay for temperatures < 30C, should have containment area or spill control plan, padded storage tank with dry air will reduce tank corrosion
  
• limit acid velocity to < 3ft/sec in pipes < 2" in order to limit erosion corrosion (erodes passive layer in pipe)
  
• Cominco has gone to stainless for acid loading and unloading because those pipes are generally open to atmosphere after use - have found much lower corrosion rates
  
• Hazards: eyes, skin, inhalation
  
• First Aid Treatment - WATER
  
• OSHA exposure limit 1 mg / m3 as mist in 8 hour period - WHO has determined that mist is carcinogenic
  
• Plant safety Issues
  
  • SCBA if entering atmosphere where mist may be present
    
  • ultrasonic thickness testing
    
  • flange wraps, especially overhead lines
    

• Trucks tanks are SS, not lined, rail cars are lined mild steel
  
• spill response - contain by diking, then react with lime or soda ash
  

New Projects:

• Alternatives to the use of SO2 as an antichlor - concern stems from safety of having SO2 on site - Ross Anderson to lead this project
  
• Acidification of Brownstock prior to Do bleaching - Ralph Lunn to lead this project