TAPPI JOURNALVol. 57, No.6
June 2003 Abstracts
Kraft Cooking with SAQ Suitable for ECF Breaching
Kawasaki Kasei Chemicals Ltd.
SAQR has been used as a cooking additive in many KP mills. This process is known
as "Quinone Cooking". In this paper, some new applications of SAQR’s
functions are proposed when ECF bleaching process is introduced in pulp mills.
First, the effect of SAQR, which decreases bleaching load keeping pulp yield
and strength by lowering Kappa number, is explained. Also, SAQR’s advantage comparing
with dispersed AQ is mentioned, especially when SAQR is used combining with Polysulfide
cooking. Finally, KKC’s study plan about SAQR’s applications to recent modified
cooking processes is described.
ECF Bleaching of Softwood and Eucalyptus Pulps−a Comparative Study
Lennart Meuller, Jiri Basta, Lillemor Holtinger and Gerd Wane
Eka Chemicals AB, S-445 80 Bohus, Sweden
This paper deals with a comparison in ECF bleaching and effluent characterisation
of kraft pulps based on softwood and eucalyptus. The study is made for both conventional
and oxygen delignified pulps.
There are similarities in the bleaching of softwood and eucalyptus looking at
the bleaching parameters. In mill scale there are however normally differences
in the number of bleaching stages for conventional and oxygen delignified pulps
when bleaching to
90 %ISO brightness. Conventional pulps are mainly bleached in a five stages sequence
with peroxide reinforcement in the alkaline stages, D (EOP) D (EP) D. Oxygen
delignified pulps are mainly bleached in a four stages sequence, D (EOP) D D,
especially softwood pulps. A three or four stages sequence, D (EOP) D D or D
(EOP) D, is usually used when bleaching oxygen delignified eucalyptus pulps.
For brightness levels of 88 %ISO a three stages sequence can be used for both
oxygen delignified softwood and eucalyptus pulps.
In the ECF bleaching optimisation study we have used a five stages sequence for
all pulps. The same bleaching sequence was used in the effluent characterisation
study except for the oxygen delignified eucalyptus pulp where a three stages
sequence was used.
Combined effluents from all bleaching stages were characterised and exposed
treatment. Characterisation studies were carried out both prior to and after
the biological treatment.
The characterisation of the main COD components; lignin, carbohydrates, methanol,
low molecular acids and extractives prior to and after external treatment, corresponded
well with the calculation of the total organic composition. The results showed
that the organic composition varies for effluents from different pulps.
The COD composition of softwood and eucalyptus effluents were significantly different,
which explains why the effluents from the eucalyptus pulps were more biodegradable.
Keywords; Bleaching, ECF, softwood, eucalyptus, COD, AOX, Effluent characterization,
New Refiner & Disperser Providing a Principle of Conical Refiner-DoubleConifiner & ConiDisc-
Aikawa Iron Works Co., Ltd
The DoubleConi-Finer is the latest designed refiner having both characteristics,
double disc type refiner and conical type refiner, which is used for low consistency
refining. The ConiDisc is one of the high speed disc type dispersers, which is
used as a disperser for hot dispersion system and is also used as a high consistency
refiner. It provides two kinds of fillings, one is conical type, and the other
one is disc type which is fixed at outside of the conical type fillings. Those
refiners having unique design improve dramatically paper characteristics and
energy consumption. This paper reports the constructions and the benefits of
those new refiners.
Energy Saving RTS-TMP Pulping and its Pulp Quality
Masahiro Ohkubo , Tamio Fukuzawa and Chiaki Kawakami
Brad Cort and Marc Sabourin
RTS is a new Low Retention, High Temperature and High Speed TMP pulping method
developed by Andritz. While the pulp quality is kept the same as conventional
TMP, the energy is 15-17% less than the conventional TMP.
Extensive studies were conducted to evaluate the development of pine pulp properties
and energy requirements using two different thermomechanical refining processes
at a southern U.S. paper mill. The processes included both a low intensity (TMP)
and a high intensity (RTS? ) refining configuration. The pulps produced with
the RTS process had 15%-17% lower energy consumption compared to TMP pulps produced
at similar freeness and handsheet physical properties. Despite similar average
fiber length results between the two processes, the low intensity pulps had a
higher percent by weight of fiber retained on the Bauer McNett 14/28 fractions,
whereas the high intensity pulps had a higher percent by weight retained on the
middle fractions. Calendered newsprint produced from the high intensity pulp
had a lower roughness, which may be related to the lower fiber size distribution.
Light was thrown on this finding by porometry measurements of the newsprint,
which revealed a slightly lower pore size distribution from paper produced with
the higher intensity pulp. Standard ink printing tests, however, provided similar
results between newsprint paper produced from the TMP and RTS? processes.
Applying Automatic Chemical Control from Stock Prep to the Machine
Roland Berger and Lydia Christen Bley
Muetek Analytic GmbH
Spectris Co., LTD. BTG division
For many years, retention-aid dosage has been controlled by the white water
consistency in newsprint, fine paper and board applications. This control strategy
is well known and has proven efficient and beneficial. However, combining retention-aid
control and charge demand control with coagulant or fixative in the thick-stock
area provides additional benefits.An on-line charge analyzer, measuring the incoming
furnish charge level, allows controlled coagulant addition so that downstream
additives are applied more efficiently and economically. This control strategy
provides substantial cost savings to the mill. Costly functional additive consumption
is reduced and other chemical control loops, such as retention-aid addition,
This paper explains the impact of white-water consistency on paper machine outcomes
such as basis weight variation, steam consumption and wet-end stability. White-water
consistency, dewatering and charge demand control approaches are discussed, and
practical examples are used to describe how short circulation and chemical composition
of the pulp affects final product quality. Mill experiences with the on-line
units, and proposed gains and benefits of these measurements to papermakers will
Introduction of a New Type Filter for White Water
Ebara Corporation, Environmental Engineering Group
For the recycling of white water from papermaking, several kinds of techniques
have been developed and put into practical use, but mainly, sand filtration has
been adopted up to present for the reason that it provides good water quality
stably. However, with the conventional white water filters, problems occurred
in the maintenance and management of operation, such as clogging of filter layers,
slime troubles, etc. caused by mud ball formation. In order to solve these problems,
EBARA has developed a new type filter provided with a surface washing agitator
which allows, during backwashing, the sand particles in the filter layer to be
cleaned by strong rubbing against each other. An outline of this machine is introduced
Diagnosis of Microbial Problems on Paper Machines
Linda R. Robertson
Principal Consultant Paper Microbiology ONDEO Nalco Co., Ltd.
Senior Account Manager ONDEO Nalco Japan Co., Ltd.
Numerous microbes are capable of growth in paper machine systems. They form
visible deposits that result in sheet defects, holes or even breaks in the web.
Microbes are also responsible for performance loss and spoilage of pulp and expensive
functional chemicals. This spoilage can lead to strength loss in fibers, formation
of odors that result in rejected products, viscosity loss in starch and a variety
of other problems. Diagnosis of microbial problems in complicated by the fact
that simple aerobic plating techniques on tryptone glucose extract agar or PetrifilmsTM
with a 48-hour incubation period do not allow recovery of all of the microbes
causing the problems. Nor do the numbers of planktonic (free-swimming) cells
correlate to the severity of deposition on surfaces. This paper will discuss
the limitations of generally accepted plating techniques and propose more accurate
diagnostic methods for solving microbial problems.
Increasing Productivity by Investing in New Technology- On-line Concepts for
Different Paper Grades -
Sumitomo Heavy Industries Techno-Fort Co., Ltd.
Running references prove that on-line technology can improve productivity through
lower costs and investments. Operating and technical demands are higher, but
they can be handled with good cooperation and hard work. Every project is individual
in terms of its demands and potential.
This means that on-line and off-line technology have to be considered case by
case in accordance with project targets and local factors such as furnish. When
applicable, on-line technology is one of the most promising options for productivity
Mitsubishi MCCR / MJ Calender
Mitsubishi Heavy Industries, LTD., Hiroshima Research & Development Center
Mitsubishi Heavy Industries, LTD. (MHI) has developed a high performance controlled
multishoe crown roll to control the caliper cross profile and MJ calender applied
the technology from shoe press. Recently better surface for high quality printing
and bulky paper for saving pulp consumption are required. MCC roll and MJ calender
meets these requirement. This paper introduces outline of MCC roll and MJ calender
and shows data from the pilot trial and field.
A Study of Sheet Gloss
Latex Research Center, Nippon A&L INC.
Recent years, requirement for sheet gloss of coated paper is steadily developing
because it is one of influential factors deciding the final quality of coated
In this paper, the relation between sheet gloss and the effective factors such
as surface roughness or optical properties was studied. Coated paper samples
were prepared with different latex binder types or different pigment systems,
then several types of surface roughness or optical properties were measured in
order to understand which property is more influential to sheet gloss.
The concluding remarks gave the following understandings.
Firstly in surface roughness measurement, although both the average roughness
Ra and the average wave length of roughness frequency Sm gave good correlations
with sheet gloss, the later was more influential. In addition, it could be understood
that surface roughness was affected by a degree of kaolin orientation.
Secondly in optical property measurements, the ratio of incidental reflectance
to the total reflectance including diffusion gave a liner correlation to sheet
gloss, the higher ratio gave the better sheet gloss.
Improved Two-Drum Winder Technology
Voith Paper Jagenberg GmbH
Today many Paper Mills have to supply rolls at larger diameters to their customers.
Very often the existing two drum winders cannot cope with the quality demands
as larger roll diameters lead to increased roll weight and therefore higher nip
pressure between roll and drums.
Excessive nip pressure results in various roll defects. So paper mills are forced
to improve their winder technology. Ideally rebuilt packages for the existing
winders should make the winder matching with their future demands.
Voith Paper Jagenberg GmbH can offer tailored solutions for many applications
by supplying special roll covers which reduce the specific nip pressure.
The Stable Flow Measurement for Stock Flow by Capacitance Magnetic Flowmeter
Takashi Okada, Jun Nishimura and Seiji Tanabe
Yokogawa Electric Corporation
The stock feed flow from stuff box is very important factor to decide the quantity
and the quality of paper. Usually magnetic flowmeters are used to measure the
stock feed flow and the accuracy mainly depends on the uniform of the conductivity
and gas fed with stock from stuff box at the start up action. We developed the
capacitance type of magnetic flowmeter and tried this meter to the line in a
series of the wet electrode type of magnetic flowmeter. The capacitance magnetic
flowmeter measurements are very stable and the outputs of both flowmeters are
quite different. This paper shows the state-of-the-art technology on the stock
flow measurement and describes the advantage for the use of capacitance magnetic
Facility Diagnosis of Acoustic Signal−Acoustic Diagnosis Technology and Application
Automation Asset Management Department, Yamatake Industrial Systems Co., Ltd
IF-ASSET is abnormal signal segregation and detection technique that was developed
based on inverse filtered acoustic/vibration signals, and was proven effective
in monitoring rotary machines, compressors, piping and high pressures vessels.
Now we intend to utilize IF-ASSET to monitor several kinds of industrial machines.
Preparation and Evaluation of Mordants for Neutral
Rosin Size Emulsion from Lignin
Yasuyuki Matsushita and Seiichi Yasuda
Graduate school of Bioagricultual Science, Nagoya University
Mordants for neutral rosin size emulsion from lignin were prepared and their
abilities evaluated. To convert lignin into the mordant, an amino group was introduced
to lignin by Mannich reaction and the reaction with glycidyltrimethylammonium
chloride (GTA). In this study, Kraft lignin and phenolated sulfuric acid lignin
(P-SAL) were used. In an experimental system composed of the handsheets made
with LBKP, sizing agent and lignin derivatives, a Mannich reaction product prepared
from Kraft lignin failed to exhibit any mordant characteristic, whereas Mannich
reaction products (MP-SAL) prepared from P-SAL were highly effective as mordants.
MP-SAL with ethylamino group especially showed higher performance. The MP-SAL
with the higher pKa value of the introduced amino group also had higher performance.
In the rosin emulsion-alum system, MP-SAL and GP-SAL, which latter are reaction
products of P-SAL with GTA, enhanced the sizing effectiveness under acidic to
neutral pH range. The handsheets prepared with MP-SAL or GP-SAL besides alum
still showed the sizing effectiveness after chloroform extraction, although the
sizing effectiveness of the handsheets prepared only with alum disappeared after
chloroform extraction. Thus, these results suggest that the enhancement of sizing
effectiveness contributed to greater association between the size and the fiber
surfaces with the addition of MP-SAL or GP-SAL. A decrease in brightness was
observed when MP-SAL or GP-SAL was used as a mordant. According to the Kubelka-Munk
theory, the brightness of original pulp with 85% brightness was calculated to
decrease 16.9% and 4.3% by adding 0.2% MP-SAL and 0.2% GP-SAL, respectively,
but the brightness decrease of a pulp with 50% brightness by adding 0.2% MP-SAL
and 0.2% GP-SAL was only 1.9% and 0.6%, respectively. This suggested that the
lignin derivatives are as capable as a mordant in newspaper and mechanical papers,
which do not require a high level of brightness.
Keywords: lignin, sulfuric acid lignin, rosin size emulsion, mordant, Mannich
reaction, epoxy reagent
Study on the Dispersion Stability of the Two Components Slurry, Composing from
SAP and MFC (Part III)Study on the Composite Structure of SAP and Microfibrillated
Japan Absorbent Technology Institute
School of Agricultural and Life Sciences, The University of Tokyo
A dispersion liquid can be obtained exhibiting a high viscosity at a low concentration
by uniformly dispersing microfibrillated cellulose (MFC) or bacterial cellulose
(BC) in a mixed medium of water and hydrophilic organic solvent.
Particulate SAP as dispersed in this dispersion liquid, SAP particles can be
stably dispersed with a high concentration in the dispersion liquid by virtue
of the viscosity exhibited by MFC. In addition, possible coagulation and recoagulation
to be caused with SAP particles otherwise coming near to each other can be almost
entirely prevented by the SAP particles being dispersed in the dispersion liquid
by the action of the dispersion of MFC, so that a dispersion slurry of a long
and stable pot life can now be prepared.
The respective behaviors of SAP and MFC in such mixed medium have been reported
in Part I of "Study on the Composite Structure of SAP and Microfibrillated
Cellulose", "Swelling & Coagulation Behaviors of Acrylic Acid Base
SAP in Water & Water Miscible Organic Solvent Mixture" 1) and in Part
II "Study on the Dispersion Stability of the MFC or the BC in a Solvent
Mixture of Water and Organic Solvent" 2) in this Journal.
As reported previously, the authors believe that they have made clear the nearly
whole picture of the conditions for stably dispersing each component, SAP and
MFC, alone in a dispersion medium. When it comes to a two component slurry system
of SAP and MFC in coexistence, various unexpected phenomenon come to take place
caused by the concentrations and concentration ratio of SAP and MFC, their different
mixing mechanisms, changes with time, coating conditions, etc. In this report,
studies have been made on the process flow of SAP and MFC being added and mixed,
their dispersion limits, stability with time of their mixed slurry, stability
at their temperatures, etc. so that the following results have been obtained:
1) It is found that MFC has the following effects in the slurry of SAP and
MFC in coexistence:
.MFC even if at low concentrations prevents coagulation and re-coagulation of
SAP by virtue of its high viscosity;
.MFC being dispersed keeping a finely particulate shape prevents bonding in groups
of SAP particles to each other;
.While SAP tends normally to swell to 1.5 to 2.2 times larger than its original
form as it selectively absorbs water in a dispersion medium, it is prevented
by MFC in coexistence from swelling with MFC retaining water out of the dispersion
medium by virtue of its high hydrating property; and
.MFC prevents the selective water absorption of SAP so as to cause the dispersion
medium not to undergo changes in composition for a long period of time.
2) The optimization of the preparation conditions of subject slurry contemplated
in a commercial process:
.In a procedure of preparing a slurry, a dispersion liquid of MFC should be first
prepared and then SAP is to be added;
.SAP has been found to be wide in its stable dispersion region if it is such
as cross linked on the surface, of spherical shape, of small particle diameter
and is obtained by being reversed phase suspension polymerization;
.The limit concentration of SAP in coexistence with MFC is 20 to 40 %;
.The limit concentration of MFC in coexistence with SAP is 0.4 to 1.0 %;
.Possible change with time of the slurry with MFC in coexistence can be prevented
by properly selecting SAP and the water content of the dispersion medium and
keeping the concentration of around 15℃.
3) It has been found that the conditions of stably forming sheets can be established
by defining a range of conditions for stabilizing the slurry.
Keywords：SAP, MFC, SAP/MFC co-existence slurry, partial swelling of SAP, dispersion
condition, sheet formation condition