JAPAN TAPPI JOURNALVol. 57, No.11
November 2003 Abstracts
Advanced Ex-Press Sheet Management for Improved Quality and Paper Machine Performance
Hideomi Uchikawa
Voith Paper Automation Japan Ltd.
Raymond P. Shead
Voith Paper Automation
The paper machine can be considered as a series of manufacturing units, each
performing a discrete function as the sheet passes through it.
The principal units are the head box, forming section, press section,
dryers and calender stack. Despite the contribution that each of
these units makes to production and quality, very little is either
measured or controlled between the forming section and ex-press,
especially when one considers that the majority of the sheet's
characteristics are born in this part of the process. For example,
nearly half the water within the sheet is mechanically removed
between these two points, with virtually no process visibility
available to optimize this part of manufacture. In addition there
are no measurements to help describe the condition of the forming
fabrics, press felts and transport belts involved in the de-watering
process. Yet most modern paper machines will change the press felts
every fifteen to thirty days as their age and efficiency reduces
productivity and quality. There is a clear requirement and justification
to do two things; first to examine the sheet at the ex press position
and secondly to use the information to improve quality of the sheet
and run-ability of the machine through its pressing operations.
Release Agent for Press Rolls
Hiraku Sawada
Maintech Co., Ltd., Sales Engineering Dev.
Deposition of pitch or fine fiber on the press rolls causes defects in the
sheet, sheet breaks and fiber rising. Especially for high speed
PMs (more than 1,200 mpm),
sheet release from the rolls is not only limiting their speed
but also giving strong impact to paper quality.
Cationic polymer has been generally used to keep the roll surface clean, however,
those program are not able to reduce draw and fiber rising effectively.
Our technology, a continuous application of chemical additives (Wax based
emulsion, On PressTM) directly onto press rolls treats surface
and establishes a protective coating that prevents deposit buildup.
In addition to preventing deposition and linting on the press rolls, this
new technology enables mills to increase PM speed and/or improve
paper quality.
In this report, basic mechanism of the roll release is explained and case
histories to various grades paper M/C are presented.
Keyword: press roll, web release, open draw, tension, pitch,
stickies, deposit, fiber rising, linting in press room
Lubricating Control & Save Lavor of Paper Machin
Kazuhiko Tanaka
Kowa Corporation, Tokyo Branch Oil Equipment Department Sales Group
There are bearings requiring to be lubricated in many points of the Paper-Making
Machine system and various way of lubricating has been thought
out and come to as present since Sairin built the model of current
paper machine in Later Han dynasty.
As main ways of lubricating, there are manually-filling lubrication,
dropping lubrication, soaking lubrication, ring lubrication, gravitation
lubricating, splashing lubrication, jet lubrication, circulating
lubrication, and grease lubrication, etc using lubricant such as
mineral lubricating oil, fat lubricating oil, mixed lubricating
oil, and grease, etc.
In this article, I would like to mention the problems and solution
concerning the circulating lubrication control using the mineral
lubricating oil, which is often used in the Paper-Making Machine.
And I hope it will be of any help to release you from the bothering
matters on daily lubricating control.
Increasing Profitability Through Filtration, Separation and Purification
Technology
- Pall Total Cleanliness Approach to Pulp and Paper Production Process -
Kazuyasu Izawa
Nihon Pall Ltd.
Contamination has been long recognized as the main source of failure to systems
including pulp and paper making machines. Many researches has been
conducted and concluded that the contamination control is the most
effective means of preventing system malfunction. Unfortunately,
the potential benefits are not being fully realized as often a
'fix' is implemented without considering other factors in the process.
This paper explains the practice of Total Cleanliness Control (TCC) which
involves a systematic and complete approach to the subject of fluid
system cleanliness. The implementation of this practice by component
producers, system builders and operators alike will enable them
to realize the benefits and the subsequent contribution to the
profitability of the company.
The Least Whole Life Costs of Progressive Cavity Pumps in the Coating Kitchen
Jeremy Jones
Business Manager, North East Asia, Mono Pumps, Ltd.
Manchester, U.K.
The principles of designing a progressive cavity pump that will give the lowest
total cost of ownership, the "Least Whole Life Cost",
are described and discussed. A balance between initial capital
cost and subsequent operating costs will result in the most economical
solution.
The factors influencing the maintenance and operating costs over the typically 20-year life of the pump include power consumption and component wear. The mechanisms of wear and the conclusions drawn from 10 years of a scientific research program are summarised.
The Mono Pump that offers the lowest Least Whole Life Cost is described, and actual site experience is quoted to illustrate the successful application of the theory.
PAM-type ply bond strength agent "Himoloc MJ-450"
Tomonori Nakamura
Paper Chemical Group, Shonan Research Center, HYMO Co., Ltd.
High ply bond strength is required in combination board. Some kinds of starches
are used as ply bond strength agents in spraying their suspension
to the combined plies. Starch suspension, without cooking, is sprayed,
and the particles of starch are gelatinized in the drying process,
large ply bond is occurred. But there are some problems such as
putrefaction in using starches. Recently, synthesized ply bond
strength agents have been used, for example poly acrylic amide
type (PAM). Our company developed cationic dispersion PAM as retention
aids and drainage aids for the first time in the world. Furthermore,
we have developed anionic dispersion PAM, "Himoloc MJ-450",
as ply bond strength agent. "MJ-450" has great performance
in small dosage because of its large particle size. The particle
size of "MJ-450" is much the same as it of starches,
and larger than it of the existing PAM. In this issue, we discuss
the differences in the fixing mechanism of particles onto the ply
between starches, existing PAM, and "MJ-450".
Compact Wet End Systems are Proven State of the Art−Experience of Sixteen Installations−
Paul Olof Meinander
POM Technology Oy Ab
Ten years ago most papermakers were convinced that a system needs to be voluminous
and heavy for controllability and stability. In order to improve
grade changing dynamics, the author of this paper began developing
a compact papermachine wet end. The results have proven that compactness
is beneficial even more broadly. Quoting Voith 1"the trend
is now the opposite - the systematic collecting and direct feeding
of the individual water flows back into the system". In its
gas-less form this is actually covered by a POM Technology patent.2
Dewatering Machine for Paper and Pulp- Rotary Press Filter -
Kouji Matsumoto
Process Engineering Development Section Machinery & Equipment Division
Rotary Press Filter is a rotational pressurized dewatering machine that has
a unique dewatering mechanism. It was developed by CRIQ, the industrial
research center in Quebec, Canada and manufactured and distributed
by Fournier Industries Inc. Tomoe Engineering Co., Ltd. started
its production under their license this year (2002).
Feature of Rotary Press are :1) High-dewaterability 2) A simple
structure 3) A tight-sealed structure that prevent odor emission
4) A small foot print 5) Less enegy cost 6) Easy and minimal maintenance
works It meets needs of today and future.
We have already installed 14 units (including sewerage application)
in Japan and installed 3 units in 2 paper making plants for their
wastewater sludge treatment. Further, we are conducting dewatering
tests on respective applications with our test machine and have
been obtaining good results. We will introduce the Rotary Press
Filter for pulp & paper industry.
"
Covercarb" (Hydrocarb CC)-A New Coating GCC for Enhanced Optical Properties-
Guillermo Bluvol
Dipl. Ing. Chem, Regional Technical Service Manager, Paper Coating Division
Almost unknown 25 years ago, ground calcium carbonate is today the most used
coating pigment world-wide in several applications.
Significant technical and economical benefits like high brightness, lower
binder demand, excellent coater runnability and improved off-set
printability are well known to the Industry.
In a number of applications however, conventional GCC pigments have the limitation
of lower hiding power and reduced opacity. Therefore it is common
practice to add opacifying pigments to the coating color for reaching
the required opacity.
The theories of light scattering on small particle can be used to explain
this phenomenon. Pigments with the high brightness, broad particle
size distribution and fine particle size of the GCC's presently
used are not optimal for opacity.
We have focused on particle size and particle size distribution to design
a GCC pigment for improved opacity. We realised that a narrow particle
size distribution (steep curve) would optimise opacity but at the
same time many of the advantages of the present pigments would
be reduced. There would be significant negative influence on coater
runnability, binder demand and solids content of the coatings using
the "ideal opacifying GCC".
Therefore a compromise was decided upon by which, as much as possible, the
present advantages of GCC would be retained in the new pigment,
while particle size distribution and average particle size would
be shifted towards that of the ideal opacifying pigment.
The manufacture of this pigment is possible by use of a modified grinding
technology.
The presentation describes the new coating pigment and gives a number of examples
where conventional GCC pigments were substituted by the new type.
The Development of Environmental Consciousness with Regard to
the Use of Dyes and Pharmaceuticals in the Paper Pulp Industry
Kunio Sugaya
Nippon Kayaku Colours. SC Marketing Development Group
Although environmental problems have been a major concern for a number of
years, it is only comparatively recently that many companies have
deemed it a matter of course to make an appropriate response to
environmental problems.
Since its foundation in 1916, Nippon Kayaku has enthusiastically
promoted such causes throughout its 80-year history, using as its
basic philosophy the following dual concepts. The company believes
in creating products that will benefit mankind and contribute to
an improvement in global living standards, paying particular attention
to the effect on health. Secondly, the company promises to respect
the environment and to guarantee the quality as well as the safety
of its products.
The paper industry was particularly prompt in dealing with environmental
issues. There has been a considerable expansion in the use of fluorescent
whiteners as well as colorful dyestuffs in general. Nippon Kayaku
has been able to supply such dyestuffs to meet the expectations
of the paper industry and has introduced a new recyclable series
of dyestuffs with excellent decoloration properties. Additionally,
a new series of liquid fluorescent whiteners requiring only water
as their solvent has been put on the market. It is also necessary
to speak of the positive effect that removing the luminosity from
bleached paper by means of fluorescence-removing agents has on
the environment.
2001 Statistics on Industrial Residuals and their Utilization
by Pulp & Paper Mills in Japan
Environmental Technology Committee, JAPAN TAPPI
Industrial Wastes Committee, Japan Paper Association
Environmental Protection Committee, Japan Paper Association
With co-operation 111 paper mills, the 2001 Statistics on Industrial Residuals
Generation and their Utilization was summarized as follows: comparing
to 2000,1) the total amount was 2,620×103 BDT and decrease by 5.3%
as much more waste paper was recycled but paper production decreased.
The total quantity utilized residuals was 1,314×103BDT, about
86% of which was composed of the three predominant ones: paper & pulp
sludge (575×103BDT), boiler ashes (330×103BDT) and fly-ashes(223×103BDT).
The large parts of these were reused as raw materials in the domestic
cement industry.
Mechanical Pulping of Cedar (Cryptmeria japonica )
Isao Onodera, Yasuyuki Kamijo and Takanori Miyanishi
Pulp & Paper Research Laboratory, Nippon Paper Industries Co., Ltd.
Cedar (Cryptmeria japonica ) is the most abundant softwood species
in Japan and has been used for construction materials, furniture,
barrels, shoes and so forth. However it was regarded unsuitable
for mechanical pulping as it contains relatively large amount
of lignin and extractives compared with other softwood species
such as spruce, hemlock and radiata pine. We tried several thermomechanical
processes by the laboratory refiner, changing chemical pretreament
and refining temperature. It was found that Cedar CTMP (chemithermomechanical
pulp) had the high light scattering coefficient and brightness,
and was suitable to produce printing grade papers.
Keyword: Cedar, Cryptmeria japonica, Mechanical pulp, Thermomechanical pulp, Chemithermomechanical pulp, Light scattering coefficient, Brightness
The Evaluation of Paper Sludge (PS) for Zeolite synthesis(Part 2)−Daily Change of Chemical Composition of PS and the Aptitude for Zeolite Synthesis−
Takao Ando, Masato Saito, Shigeo Muramatsu and Kimio Hiyoshi
Fuji industrial research institute of Shizuoka prefecture
Junsuke Haruna, Naoto Matsue and Teruo Henmi
Department of agriculture, Ehime Univ.
We have been investigating zeolite synthesis from paper sludge (PS) ashes.
This technique is essential from the viewpoint of recycling of
wasting materials.
In our previous study, the PS ashes from 20 paper mills in Fuji area of Shizuoka
Pref. were examined on suitability for starting materials in the
zeolite synthesis, and they were classified into 4 types of compositional
ranges in terms of talc-kaolinite-calcite composition; that is,
ranges (A) and (B) were suitable for the zeolite synthesis and
ranges (C) and (D) were not suitable.
In this study, we selected representative 4 mills that had discharged PS corresponding
to the above 4 types of compositional ranges, and the chemical
and mineralogical compositions of PS from these 4 mills were analyzed
for 5 days. As a result, the following conclusions were obtained.
The PS samples from the mills that had initially discharged PS belonged in
the ranges (A) and (B) did not change into the ranges (C) and (D)
for the period of 5 days. The samples belonged in (A) and (B) showed
again being suitable for the zeolite synthesis.
PS discharged from a paper mill that makes products including a lot of kaolinite
is suitable for the zeolite synthesis. However, PS containing too
much calcite is not suitable.
Keywords: zeolite, paper sludge, calcite, talc, kaolinite
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