1) Polyester plant design and engineering is becoming more competitive as new companies enter the market, particularly in China, where domestic Chinese engineering capabilities are growing. 2) Traditional large engineering companies still dominate the largest plants at 800 tons/day or more, while new companies have increased their market share and can build plants up to 600 tons/day. 3) There is a trend toward simplifying polyester processes by reducing the number of steps to cut costs, with some new technologies achieving savings of up to 21% in conversion costs.

1. RAW MATERIALS
Polyester plant design and have a positive consequence for technol-
ogy owning engineering companies in
future. Different to the past, where large
engineering today and tomorrow production companies had the reliance
in their in-house engineering to erect
U.K. Thiele, Dr. Thiele Polyester Technology, Bruchköbel/Germany
polyester plants using home made, li-
Summarizing the consulting experiences ester lines, the capabilities to build censed or copied technology, it will be
of the recent years, the essence of im- "World Scale" and competitive continu- hardly probable in the future that an en-
portant polyester conferences like the ous polyester melt phase plants is pre- gineering department which erects a
yearly Polyester World Congress in sented in Table 1. new plant every now and then will take
Zurich/Switzerland and fairs like The reported numbers of plants and the risk and responsibility for such large ca-
ACHEMA and ITMA, the description of related melt phase capacities might be pacity and investment projects. Here
current status of polyester plant design different from source to source, but the again, the cooperation between poly-
and engineering business provides an message is clear. Besides, China is the ester producer and engineering might be
interesting picture. One proven fact is the leading country in polyester with a pro- the most successful model.
significant decline of new polyester proj- duction capacity of nearly 14 million
ects in Western Europe and America tons/year. The Chinese engineering ca- Process simplification and
and the sharp increase of projects espe- pability to build world scale melt phase optimization
cially in China and Eastern Europe (see plants also has to be considered. It should Besides the steadily increasing plant ca-
pages 40-46 of this issue). At the same also be mentioned that SSP technology pacity, one can recognize the clear trend
time the number of companies fighting for bottle polyester in China is on the way toward the reduction in process steps.
for market shares of polyester plant en- to becoming independent soon. At the The three step process of esterification,
gineering has surprisingly increased. end of 2004 Yizheng will start up its first pre-polycondensation and polyconden-
homemade solid state polycondensation sation as applied for many years by the
Polyester engineering on the move plant with a capacity of 275 tons/day DuPont/Chemtex technology, is becom-
As little as five years ago the market of based on a joint development with CTIEI. ing more and more common nowadays.
large continuous polyester plants, even Companies such as NOY Vallesina Engi-
in China, was completely dominated by Plant capacity development neering or CTA/SINOPEC are designing
the leading engineering companies like How conservatively capacity develop- their plants based on this process phi-
Chemtex using DuPont technology, Zim- ment was seen only 8 years ago is losophy.
mer AG, Inventa-Fischer, Kanebo and demonstrated in the comparison Fig. Significant further progress is made by
Hitachi whereupon large producer like The limitation of maximum plant capaci- Inventa-Fischer with their new two step
Nanya, Hyosung, Eastman (Voridian), ty differs significantly between PET resin process applying a tower reactor con-
Mitsubishi, Mitsui, Toray or Tuntex took for bottle applications and textile chips taining esterification and pre-polycon-
planning, design and erection of new on the one hand and direct conversion of densation as well in one housing as a
plants into their own hands. melt to textile fibers and filament yarns at first reactor, and polycondensation as a
Today, even with the smaller market the other hand. For chip production there second reactor. The compact design al-
shares of new investments in Europe and is, besides mechanical limits of vessel lows savings in conversion cost of up to
America the number of companies which sizes and vessel transport logistics, no 21 %, which means a reduction of total
are fighting for this market and which are real upper limit, and plant capacities of production costs by 3.5-4.0 %. Having
able to deliver world scale polyester up to 1500 tons/day and higher will be the small profit margins of the PET busi-
plants has increased remarkably. New- realistic in the near future. The best ex- ness in mind, this development might at-
comers and developers in Europe like ample for this development is the new Al- tract future investors. The patented
NOYVallesina Engineering, EPC-indus- tamira line of M&G which was originally "ESPREE" technology [4] has already
trial-engineering or AQUAFIL Engineer- designed for 750 tons/day, which has been introduced to industrial size and
ing and in China companies and design reached an output of 1000 tons/day and executed in four polyester projects with
institutes like Huitong Polyester [1], which is under further capacity optimiza- current largest capacity of 250 tons/day.
CTIEI/CTCEC [2] and CTA/SINOPEC [3] tion. This process route is becoming The scale up is on the way.
are increasing the competition potential more and more comparable to the huge Another new polyester process technol-
enormously. Especially the market in Chi- bulk production lines of polyolefines. ogy called NG3 proprietary to DuPont,
na changed drastically. When the above As opposed to this, the direct conversion which was introduced to the public dur-
mentioned leading traditional engineer- of polyester melt to textile fibers and fila- ing the 1990s, raised high expectations
ing companies covered about 80 % of the ment yarns might capacity wise be satu- regarding savings in investment costs
market share in China six years ago, this rated at about 600
share has shrunk currently to less than tons/day. The latter Table 1
40%, and this process is rapidly ongoing. process is limited Established engineering companies:
The latest bank loan policy of the Chi- in the residence Chemtex/DuPont + M&G: 800 tons/day, 3-stage-process: bottle grade,
nese government especially, where in- time of PET melt in operation at about 1000 tons/day in Altamira/
Mexico, further output increase is in preparation
stead of 10% now about 50% net equity which should, for
Chemtex/DuPont: More than 15 lines over 500 tons/day
is necessary for new projects, will force reasonable spin- Chemtex/DuPont (NG3) 2 lines 600 tons/day
Chinese investors to turn to domestic ning results, not Inventa-Fischer: 10 lines 500 - 600 tons/day including challenging
engineering companies which are able exceed 30-40 min- projects such as direct processing of BOPET
Zimmer AG: 3 lines 600 tons/day, 7 lines 300 - 500 tons/day
to strongly undercut the import prices. utes depending on
melt temperature. New companies in China:
Capability to build world scale plants The rapidly ongo- CTIEI/CTCIC: 20 lines 500-600 tons/day, 10 lines > 300 tons/day
CTA/SINOPEC: 1 line250 tons/day, 1 line 400 tons/day
Looking at the results of the recent years ing capacity Huitong Polyester: 1 line 250 tons/day, 1 line 300 tons/day
expressed in erected and running poly- growth might also
230 CHEMICAL FIBERS INTERNATIONAL Volume 54, September 2004

2. RAW MATERIALS
rayed to cut pro- vious passage there is new design for a
duction costs and two reactor compact melt phase poly-
to simplify technol- condensation of 200 tons/day already
ogy or distribution available on the market. Finally, one has
logistics. Because to puzzle the currently present best tech-
savings in trans- nologies together, and of course one
port and ware- must take the comparable high risk to
house costs are become the first user of direct preform-
becoming increas- ing technology
ingly important At this point the largest direct conversion
with declining mar- film project must be mentioned. Out of a
gins, there is still melt phase finisher of a capacity of 600
space for develop- tons/day polyester melt 400 tons/day
ment for those thereof will be directly converted to biax-
companies which ial oriented film in a thickness range of
are fully integrated 12-36 µm in four parallel lines of a ca-
Development of capacity: figure published in 1996 [4] and the with the raw mate- pacity of 100 tons/day each. The remain-
current situation
rials PTA and EG. ing 200 tons/day polyester melt are con-
and quality improvements. Here, the tra- Here, the physically closer coupling of verted to film granulate.This project is un-
ditional melt polycondensation under PTA and EG production with the conver- der construction in China.The melt phase
vacuum is completely replaced by the sion to polyester might provide further plant which provides the film polymer to
SSP which reduces the chemical part of cost saving potential. the BOPET lines including the melt dis-
the plant to a two reactor process. There tribution to the single film lines is de-
might be unexpected problems or hur- Direct conversion processes signed and executed by Inventa-Fischer.
dles during the first industrial start up of Having had the good luck to have start-
the new process as there is no official ed up a new process development near- Future prospects
statement on the status of the projects ly a decade ago as co-inventor, it is now In summary it can be said that polyester
currently available. satisfying to notice that this technology is plant design and related engineering busi-
Saving costs and cutting process steps on the way to its first roll out soon. Meant nesses are under increasing competition
on a somewhat smaller scale is also the is the direct performing or melt to pre- pressure whereas the serial erection of
background of the recently announced form process which today, is investigated standard type polyester plants in China at
combination of under water pelletizing and developed by Inventa-Fischer [7] sizes up to 600 tons/day is on the move to
and crystallization by Kreyenborg [6]. and Zimmer AG [8] in pilot scale condi- Chinese engineering companies. As a
Keeping sufficient heat in the pellets dur- tion. Both companies presented their ex- consequence, one could expect Chinese
ing the cooling period by heating up the perimental concept in pilot scale togeth- engineering activities outside of China af-
cooling medium to a range where the er with the melt to preform machinery to ter the Chinese market is saturated. To
polyester chips will remain at tempera- the interested public. Some details e.g. sustain and even grow in this business
tures between 160-110 °C provides a how to reduce the AA-content to the de- thus needs a straight-forward and long
quick crystallization in the presence of manded low AA-level for water packag- term research and development commit-
water. The resulting chips have a degree ing without spoiling the polymer by ment in order to serve customers with high
of crystallization in a range of 40 % ac- adding high amounts of AA-scavengers, quality and cost saving polyester produc-
cording to Kreyenborg, which is enough or how to manage the seasonable and tion and conversion technology. Besides
for a safe and lump formation free drying fashion driven flexibility of preform de- further substantial capacity increases,
step without crystallization. This technol- signs, are still under question. Yet like 35 there are process simplifications and fur-
ogy will especially interest those proces- years ago the step from extrusion spin- ther integration to raw material produc-
sors who aim for PET applications in ning to direct spinning, which was driven tion, direct conversion melt to preform or
packaging and engineering plastics. by enormous cost savings, the melt to melt to film, as well as intelligent plant op-
Another path to satisfy the growth of poly- preform process will become reality in timization and the revamp of important
ester production, besides the erecting of the near future. It would be recommend- fields to be distinguished from me too en-
new plants, is the substantial capacity able for those who are producing pre- gineering. Not forgetting the myriads of
boost of existing continuous lines. By un- forms now and who are still skeptical the existing discontinuous and low ca-
derstanding process kinetics, heat man- about the future development of their pacity continuous lines. To survive in the
agement and internal flow conditions in business to have a deeper look at con- market they will need to produce highly
detail, it is possible to increase the plant tinuous direct spinning- and fully-auto- specialized polyester products, which is
output of existing plants up to the double mated POY plants as they are newly in- another field of know-how developing en-
name plate capacity by replacing the bot- stalled at large textile yarn producer gineering companies.
tlenecks and redesigning important sin- around the world.
Literature
gle parts such as finisher internals, The direct preforming plant capacity [1] http://www.chinapolyester.com/
scraper condensers, process columns or might start at an output range of about [2] http://www.ctiei-overseas.com/index.html
heat transfer equipment. This field, for in- 100-200 tons/day which means at like- [3] http://www.cta.com.cn/en/intro.shtm
stance, is the special domain of EPC in- wise low melt phase capacity. The well [4] Schumann, H.-D. Thiele, U.K., Polyester Produc-
ing Plants, Verlag moderne industrie, 1996
dustrial engineering which offers expert- known correlation between plant capaci- [5] WO 03/042278
ise and process knowledge to fill this mar- ty and conversion cost where the largest von Endert, E., Chemical Fibers International,
ket niche. melt phase capacity secures the lowest 54 (2004) 164-166
[6] WO2004033174
Besides reduction of process steps or cost might raise the question of the [7] EP0727303
number of reactors or equipment parts, economy of scale for this new direct pre- [8] US5656221
the whole production chain has to be x- forming process.Yet as shown in the pre- Chemical Fibers International 54 (2004) 161
Volume 54, September 2004 CHEMICAL FIBERS INTERNATIONAL 231