An Inside Power-plant for the
Purpose of Saving Energy and CO2 Reduction
Shigeaki Obayashi
The First Energy Service Company, Limited
The Kyoto Protocol, an international and legally binding agreement
on gases emissions has entered into force on 16 February 2005. To
meet this protocol, Japan has to step up in a new phase for CO2 reduction.
On the other hand, the law of saving energy, which was established
by METI (Ministry of Economy, Trade and Industry), has been revised
several times in order to tighten up the original. So the private
sector has been requested more efforts for saving energy.
Recently, crude-oil price has risen more than twice as compared
with that of two years ago, and also has set the record of 70 US
dollars
per barrel last summer. Under these circumstances, it is seriously
required an introduction of more effective plant system or less fuel
consumption plant.
In this paper, we explain the recent engine for the power generation
in the use of an inside power plant, and aim to give some suggestions
for saving energy, reducing CO2 and also saving cost. Also we briefly
explain the ESCO (Energy Service COmpany) which is recently adopted
in many companies as a way of introducing plant system for saving
energy.
Energy Saving by Introduction of the Gas Turbine Cogeneration System
Hiroshi Nagata
Kanzaki Mill, Oji Paper Co., Ltd.
Located in the city of Amagasaki, Hyogo Prefecture, where the
Kanzaki river a tributary stream of the Yodo river, the source
of which
is Lake Biwa-flows into the Osaka bay, the Kanzaki mill is an urban-style
mill in the Kei-han-shin metropolitan area. The mill has 25 million
population in its background. The mill started the production of
coated paper in 1922. The coating technology has been handed down
to us through the mill’s long history. Since then, it has undergone
various changes, the mill is well known as a mill manufacturing
various processed paper by the communication paper.
Here, in Amagasaki, as same as in other industrial arrears in
Japan, we must positively make efforts to solve the problems in
order
to meet more severe environmental standards on air and water pollution,
legislated by Amagasaki city and Hyogo prefecture.
Since the mill introduced gas turbine cogeneration system instead
of conventional and gas boiler and steam turbine generating system
in September 2003, we introduce the way and result of energy saving
by taking this system as a case.
Energy Saving in the Bleaching Plant
- Steam Saving Examples by Raising the Temperature of Hot Water
-
Tomomi Inaba
Nippon Daishowa Paperboard Yoshinaga Co., Ltd.
Nippon Daishowa Paperboard Yoshinaga Co., Ltd. has been trying
to expand the use of recycled paper with taking advantage of a
good location near the Tokyo metropolitan area.
New No.5 incinerator has been operated from December 2002 for
the purpose of incinerating paper sludge and generating power for
mills
facilities. But a consumption of fuel oil has been continued at
a high level, then we have lost significant earnings as a result
of a sharp oil price increase in recent years, we have felt a strong
need for energy saving.
No.1 bleaching plant is located apart from the cooking plant and
the chemical recovery plant, so it can not use the heat from black
liquor. For the reason, it consumes the large amounts of steam.
This report describes steam saving examples by raising the temperature
of hot water with using the heat of absorbent in No.5 incinerator
desulfurization equipment.
Energy Saving with ID-Screen
Hirotada Tsukakoshi
Nayoro Mill, Oji Paperboard Co., Ltd.
We have pulper, screen, a process of refiner in raw materials
process producing wastepulp from wastepaper as facilities using
particularly big energy.
In paper manufacture industry of energy many consumption model, it is a point
to be connected directly with cost reduction to promote energy saving positively.
I introduce ID technology of Aikawa Iron Works Co., Ltd. into existing screen
this time and I remodel it into dilution white water injection model screen (ID
screen) and introduce the example that wrestled to power-saving
CO2 Reduction by Remodeling the Existing Boiler to the Gas Firing
Takao Koide
Power Plant Service Center, Mitsubishi Heavy Industries Limited
KYOTO protocol has taken effect since February 2005 and Japanese
government requests industries to reduce 8.6% of CO2 emission in
2010 compare to 1990 as the aim. Addition to that, fuel oil price
is getting higher recently, because of high crude oil price.
As a result, the company which has oil firing boiler has to study
the reduction of CO2 emission and fuel oil cost for boilers.
Therefore, MHI suggests the remodeling the oil firing boiler to
the gas firing for the reduction of CO2 emission and fuel oil cost
simultaneously.
In this thesis, general and example of gas firing modification
are introduced. And also, finance lease of sate light base for
gas supply instead of gas pipe line, which MHI will provide, is
introduced.
Energy Saving by Installation of Boiler Exhaust Gas Heat Recovery
System
Satoshi Takai
Nomachi Mill, Chuetsu Pulp & Paper Co., Ltd.
In late year, as the issues concerning Environment and Energy
are taken close-up globally, the measures to meet them became the
urgent
business. Then so-called Kyoto Protocol was taken effect as an
anti-global warming measure in February, 2005. Reduction of the
carbon dioxide discharge was fixed against Japan based on it. Japan
Paper Association fixed the following target as a voluntary action
plan.
1) Reduce the fossil energy consumption per ton of paper by 13% until 2010 compare
with the
1990 level
2) Reduce the carbon dioxide discharge per ton of paper by 10% until 2010 compare
with the
1990 level
On the basis of such a world trend, we in Nomachi Mill are wrestling with deducing
the environmental load, with promoting the energy saving and the effective use
of waste paper and wood resources. In Nomachi Mill, as a part of long term energy
saving, we installed Boiler Exhaust Gas Heat Recovery System in the effluent
gas chimney flue of the No.3 Recovery Boiler in July 2005 and decided to utilize
the waste heat for warming the feed water of the above mentioned boiler. I want
to introduce the example as follows.
A Reduction Approach to CO2 Emissions by Introducing a Large-scale
Recovery Boiler
Shigeru Wakamoto
Niigata Mill, Hokuetsu Paper Mills, Ltd.
The approach of measures for controlling global warming and energy
conservation has became important more and more by coming into
effect the Kyoto Protocol in February, 2005. Additionally, conserving
energy has been getting important as a measures of recent sudden
rise of crude petroleum. Hokuetsu Paper, Niigata Mill introduced
a large-scale recovery boiler in April, 2005 to replace the superannuated
boiler, decrease the air pollutant, etc. Therefore, the plan of
both air pollutant reduction and energy conservation were started
by considering the best operating combinations of the new boiler
and the existing boiler. In this report, the approaches of energy
conservation and the CO2 reduction are described after introducing
outline of the large-scale recovery boiler.
Water Jet Turning-Up System
Makoto Matsushita
KGK Engineering Corp., NUSM Division
Paper mills have been long after the turn-up efficiency improvement
and subsequent paper loss reduction. Our full automatic “ReelJet”
turn-up system (Paprima Industries Inc., Montreal, Canada) uses
2 units of ultra high pressure water-jet cutting head (1300-1500bars/20cc
per turn-up) which run fast (2m/sec) to their waiting position
each side of the line to get the sheet expanded to its full width
keeping a completely uniformed wrapping both ways from the center,
immediately after the tail has got caught by a new spool with the
help of an air-coanda effect of a specially designed gooseneck.
Thus, “Reel Jet” makes it possible to execute turn-ups failure
free in such a shorter time span as 2 seconds since the issue of
turn-up command via DCS until the two heads come back to their
park-positions. Also, its beautifully balanced and even wrapping
on a spool can release the reel part from vibration and noise related
problems.
Its sales has been expanding among big scale world famous paper
machines in Europe and North America, and they are quite satisfied
with its overwhelmingly nice performance to cut paper loss and
subsequently to improve productivity remarkably. Hereunder, we
are going to explain about its structure and performance.
Solutions for High Quality Tissue Creping
Yoshinori Sekiyama
Sales Engineering Dev., Maintech Co., Ltd.
The Yankee dryer is a critical part of the tissue making process
and its surface plays an important roll in achieving good sheet
quality. Therefore, it is imperative that the Yankee surface is
well protected. Maintech has developed “Ultra Lubrication Creping”
an innovative and unique method in which Yankee dryer is protected
by a lubrication coating layer composed of resin and disulfide
molybdenum. The resulting surface reduces the friction between
the dryer and doctor blade and extends the life of doctor blade
dramatically.
Also, felt filling due to pitch and/or stickies can lead to any
number of problems, including unstable coating layer, poor sheet
quality, lost production, unscheduled shutdowns, and increased
operating costs. Maintech has developed a series of deposit control
products “MainteClean” whose amphoteric polymer prevents the pitch
and/or stickies from accumulating on the felt and felt rolls. The
treated felt gives positive impacts not only on the felt condition
but also on the dryer coating.
This paper reviews the innovative methods of Yankee coating and
felt conditioning comparing with conventional methods. Case histories
illustrating gained benefits in tissue grade M/C are presented.
Low Consistency Refining Technology
LemaxX Spiral - Nature Applied
Kenichi Ito
Andritz k.k., Japan
Peter Antensteiner
Durametal Corporation
Andritz is a leading supplier of refining technology in the world.
Also Andritz supply wear materials for refining process. Durametal
Corporation, a subsidiary of Andritz, produces the refiner plates.
This company has over 8,000 patterns of refiner plates and several
new patterns developing in a week. Also Durametal plans to develop
a simulation program “MAGNUS”, it is simulate the “Nature of Refining”
theory. Using this program Durametal Corporation developed The
Logarithmic Spiral Design refiner plate LemaxX Spiral.
This report introduces the performance of LemaxX Spiral technology.
Wastewater Treatment in Japanese Pulp and Paper Mills Today
Environmental Technical - Committee of Japan Tappi
Environmental Protection Committee, Japan Paper Association
This survey of wastewater treatment in the Japanese pulp and paper
industry is based on operations of 102 mills in 2002. Data covered
98% of pulp production (except recycled pulp including deinked
pulp, DIP) and 89% of the production of paper and board products,
and was compared with the last survey’s in 1991.
As the Japanese economy had been sluggish in this 11 years, pulp
production in 2002 decreased by 9% and paper and board production
was confined to 10% increase. One third of the mills each produced
annually over 0.3million tonnes of market products. 72% of the
mills produced both pulp and paper products. 31% of the mills had
kraft pulping process. Half of the mills discharged effluents into
rivers and 41% into seas. Enclosed coastal seas (Tokyo Bay, Ise
Bay and Seto Inland Sea) received effluents from 30% of the mills.
Enhanced awareness of the environmental preservation in Japan
has further strengthened the effluent limitations. Discharge limits
of suspended solids (SS) and biological oxygen demand (BOD5) were
lowered by an average of 20% and chemical oxygen demand (CODMn)
by 10%.
As the results of sustained effort of the Japanese pulp and paper
industry, the average specific discharge of SS in 2002 has decreased
to 2.6 kg per ton of market products, BOD to 2.8 kg/t , COD to
7.4 kg/t, and the average specific consumption of water has been
lowered to 88 m3 /t , which corresponded to a reduction of 29%
on SS, 42% on BOD, 30% on COD and 16% on water consumption.
Though coagulation-sedimentation was still the mainstream of wastewater
treatment, the multistage processing including some biological
treatments has spread progressively. Many activated sludge plants
have shifted their aeration gas from air to oxygen, and then more
than 50% of BOD and COD loads in wastewater have been removed by
the activated sludge process.
The average operational staff of wastewater treatment was 4.7,
decreased to one third from 1991.
International Conference Report
― The 5th Biennial Johan Gullichsen Colloquium, Finland ―
Toshiharu Enomae
Graduate School of Agricultural and Life Sciences, The University
of Tokyo
On November 17th, 2005, the 5th Biennial Johan Gullichsen Colloquium
was held in Helsinki, Finland. This colloquium was initiated by
Professor (currently emeritus) Johan Gullichsen of Helsinki University
of Technology in order to encourage especially young engineers
and scientists. The 5th colloquium featured “Raw materials and
processes ― viewpoint of product” and covered a wide range of topics
including 5 categories and 8 aural presentations from all over
the world. The summary of those presentations are reported.
Report of Studying at University of Maine
Kenji Hirai
Research and Development Dept., Product Development Research Lab.
Nippon Paper Industries Co., Ltd.
The author had an opportunity to study at University of Maine
for one academic year of 2004. The author has belonged to Paper
Surface
Science Program (PSSP) in chemical engineering department of University
of Maine as a visiting scientist. In this report, mission and current
research activities of PSSP, the impression of the studying and
the life at University of Maine are reviewed.
Keywords: University of Maine, Paper Surface Science Program,
PSSP, Visiting scientist
Reduction of AOX by Prolonged ClO2 Bleaching under High Temperature
and Acidic pH Conditions
Kengo Magara, Tsutomu Ikeda, Tomoko Sugimoto and Shuji Hosoya
Department of Chemical Utilization, Forestry and Forest Products
Research Institute
Decreases in AOX during chlorine dioxide bleaching at high temperatures and
under acidic conditions were investigated. When the temperature in the chlorine
dioxide bleaching stage was raised from 70oC to 95oC, a certain decrease in
AOX was detected. AOX is formed by a chlorine substitution reaction with mainly
lignin and chlorine that was generated from a reduction of chlorine dioxide.
For the chlorination of lignin, it appears that raising the temperature facilitated
an oxidation reaction rather than a substitution reaction, so that the rapid
consumption of chlorine in the oxidation reaction suppressed the substitution
reaction.
Extension of the bleaching period from 15 min to 90 min also decreased AOX discharge.
In the first chlorine dioxide stage in bleaching, high temperature and acidic
pH were employed to hydrolyze hexeneuronic acid as well as remove lignin. In
this bleaching condition, some of the lignin was also subjected to hydrolysis.
However, the cause of a dehalogenation reaction that was required to decrease
AOX is difficult to understand. To determine the cause of dehalogenation, some
chlorinated compounds such as a chlorinated aromatic compound and a chlorinated
organic acid were heated at 95oC for 90 -120 min under acidic conditions. However,
no explanation could be found to account for the decrease in AOX. Therefore,
further investigation should be conducted to determine why the AOX reduction
was induced by prolonging the bleaching period.
Keywords: chlorine dioxide bleaching, AOX, high temperature, acidic pH, bleaching
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