By Annie Zhu, Features Editor, PPI magazine, RISI
BRUSSELS,
Oct. 31, 2008
(Viewpoint) -
The shortage of wood pulp supply in China, due to the nation’s limited forest resources, is well known. In order to tackle the problem, the government has encouraged local pulp and paper companies to plant trees and to build large scale pulp lines under forest-pulp-paper integration policies. In Huaihua city in Hunan province, in the southwest of China, the nation’s largest BSK pulp line has started commercial production at Hunan Tiger Forest & Paper’s greenfield mill, Hunan Juntai Pulp & Paper.
Supplied by Andritz, the pulp line has a design capacity of 400,000 tonnes/yr of bleached softwood kraft pulp, although it is also capable of manufacturing bleached hardwood kraft pulp.
After being granted a government license in December 2005, Hunan Juntai Pulp & Paper started construction of the mill in Feb 2007, after laying the foundation stone in June 2006, with an approved investment of RMB 4.35 billion ($640 million), of which RMB 3.15 billion ($461 million) was used in building the mill and the remaining RMB 1.2 billion ($146 million) has been slated for developing forest resources.
The pulp drying line’s market pulp was proved to meet market standards in May, followed by trial runs in Aug 2008.
“World conventional practice is to take 150 to 200 days to optimize systems to reach the design capacity, but we aim to use less than 90 days, and to reach the design capacity of 400,000 tonnes/yr by the end of October,” says vice chief engineer of Hunan Tiger Forest and Paper, Huaihua project vice commander, He Ganghui.
This high speed has also applied to the greenfield mill’s construction, which only took one year, while world conventional practice is more than 20 months, explains He Ganghui.
Wood supply
The mill was chosen for its location near local forest resources, and government policy encouragement. “Since the 1970s China has planned to build a big pulp mill where resources are relatively rich, and this has also reflected China’s ambition to develop industry in this area,” says He Ganghui.
Huaihua has 1.745 million ha of forest area, with 66.95% forest coverage, ranking top among all the cities in China according to He Ganghui.
“However, local farmers have long used the wood for fire and to cook meals, which is a waste. So we have been collecting the branches and small wood to feed the pulp line to improve resource usage, and also to tidy up the area,” adds He Ganghui.
|
| Woodyard |
Capacity |
350 m³ sob/h |
| Fiberline |
Capacity |
1242 adt/d SW, 1358 adt/d HW |
| Bleached pulp brightness |
up to 90% |
| Evaporation |
Capacity |
480 t H2O/h |
| Dry solids |
80% |
| Recovery boiler |
Capacity |
2200 t DS/d |
| Steam values |
480°C, 84 bar |
Currently, smaller sized wood supplies (commercial woodchip) sourced from local farmers accounts for 45% of the wood supply of the pulp line, while the remaining 55% comes from Hunan Tiger Forest & Paper’s own plantation in Hunan Shaoyang, south east of Guizhou, Yunnan, Sichuan and Guangxi provinces.
“In total, the mill needs 2.2 million m³ equivalent of roundwood per year,” says He Ganghui.
Starting to prepare raw material in October last year, the mill has stored 750,000 m³ of roundwood up to now, and also more than 100,000 m³ of commercial woodchip.
“This is enough for this year’s storage, and we need to purchase more for future production,” says He Ganghui. He expects that Hunan Tiger Forest & Paper will expand its plantation to 1.5 million mu (100,000 ha) over the years.
A 9.88 km long railway siding connecting to national lines is also being built near the site for pulp transportation.
The plant covers 1800 mu (120 ha), with 400 mu (27 ha) newly added for raw material storage needs.
Equipment and process
Andritz supplied the whole pulp line - the largest BSK pulp line in China - with key equipment. The country’s biggest pulp line is owned by APP China’s subsidiary Hainan Jinhai Pulp & Paper and has a BHK capacity of 1 million tonnes/yr.
Andritz’s scope of supply includes the systems for wood handling, cooking, washing, screening, oxygen delignification, bleaching, pulp drying, bale handling, and the chemical recovery island (evaporation, recovery boiler and white liquor plant).
“During the open bidding process, Andritz’s whole system supply scope proved to be the widest among all the competitors. We have thought about using different suppliers for different departments, however, Chinese mills have encountered difficulties in the past with this approach. Moreover, Andritz’s past experiences in supplying whole pulp lines, including in Uruguay and Brazil, prompted us to make the final decision, to ensure consistent technical support and coordination,” says He Ganghui.
Hunan Tiger Forest & Paper’s chairman, Wu Jialin, commented on production so far: “At present, production running is stable, and the quality is good, waste treatment has exceeded the most advanced technology, and now the whole project has achieved success,” says Wu.
For the woodyard, Andritz has delivered one of the biggest single debarking line in China. Horizontally fed HHQ-Chippers in the woodyard are designed to ensure high chip quality.
The use of the Turbofeed Chip Feeding system and DownFlow Lo-Solids cooking process makes the cooking plant extremely simple and easy to operate.
The washing for brown stock and bleaching is done with Drum Displacer washers in order to achieve high pulp cleaness and brightness with low chemical consumption. Two stage oxygen delignification gives maximum kappa reduction while preserving pulp strength.
Bleaching is done with oxygen, chlorine dioxide, peroxide and caustic in the sequence D0-EOP-D1-PO. Final pulp brightness is up to 90% ISO, according to Hannu Ramark, general manager, Pulp Mill Technologies.
The pulp drying plant system includes Twin Wire Former technology for high throughput and high dryness into the airborne sheet dryer.
The Andritz Twin Wire Former provides very gentle and efficient dewatering with good sheet formation and strength and highest throughput, says the supplier. A further advantage is rooted in the concept of the wet end which gives high flexibility in matters of feedstock as well as changes in the process and long wire life.
Andritz’s senior project manager, Pulp Drying Lines, Helmut Senft, is satisfied with the progress so far. “After a short time running with purchased pulp, the pulp drying line was running for the first time with pulp from the fiberline on July 14. Since August 3, the start of commercial operation, the pulp drying line has been running continuously with pulp from the fiberline and by September 8 we reached a capacity of 1044 ADMT/yr, which is more than 75% of the guaranteed production value. From all points of view we are very satisfied with the current operation of the pulp drying line and feel confident to run at guaranteed production very soon,” says Helmut Senft.
“The dryness of the market pulp is 90%, which is a very good value and saves energy in transportation, compared to China’s domestic suppliers, where pulp dryness stays at 85-90%,” says Andritz’s general manager, Pulp Drying and Bale Finishing, Martin Kroboth.
The line’s output has reached 80-88° brightness, the levels Chinese buyers favor. The firm is now selling two grades of BSK – one has 80-84° brightness and the other 84-88°.
Andritz has also delivered the complete recovery island, including evaporation plant, recovery boiler and white liquor plant. The recovery island is designed to produce the maximum amount of green energy with lowest possible steam and power consumption.
Other suppliers to the mill include ABB and Siemens Automation.
Environmental issues
He Ganghui believes that Andritz technologies enable the mill to meet high environmental requirements. Both air and water emissions are very low.
“We have spent RMB 60 million ($8.8 million) to 70 million ($10.3 million) on waste water treatment, and the mill’s COD emissions reached 50-80 mg/l at their best level, well below the government’s requirements for pulp mills at 200 mg/l,” says He Ganghui.
The government in China changed the discharge standard of water pollutants for the pulp and paper industry in June 2008, the sixth change since its launch 25 years ago. The COD emission requirement for pulp mills has been changed to 200 mg/l compared to the old standard at 350 mg/l, indicating the nation’s concerns over environmental issues, and its ambition in saving energy and reducing emissions in the pulp and paper industry.
|
| Pulp type |
Bleached kraft pulp |
| Furnish |
70% of time softwood (80% mason pine/20% fir) 30% of time hardwood (eucalyptus, alder, poplar) |
| Production |
1350 ADMT/d |
| Basis weight range |
1000 - 1200 g/m² |
| Design speed range (drive) |
80 - 250 m/min |
| Final pulp sheet dryness |
90 BD |
| Sheet width at cutter |
4200 mm |
| Bale weight |
approx. 333 or 250 kg |
Moreover, the mill is also extremely energy efficient by maximizing electricity production.
“The mill uses biomass, including black liquor recovery and tree bark, to generate more than 400 tonnes/h steam; the installed 70 MW/h steam turbine can produce more than 40 MW/h electricity, which is supplied to the national grid when in excess of internal use, thanks to Andritz’s high efficiency experience. It means that we don’t use external electricity, and don’t generate toxic emissions,” says He Ganghui.
He Ganghui adds that the mill has also installed waste water color improvement systems with an aim to improve the water treatment, to reassure the local community.
Water consumption of the mill is less than 30 m³/tonne, well below the nation’s average level at 100 m³/tonne.
Hunan Juntai Pulp & Paper has invested RMB 590 million ($86.4 million) in environmental protection measures for the mill, says Hunan Tiger Forest & Paper’s internal newspaper.
Less than 400 people work in the mill, the average age is 21 to 22 years, most have a university background, says He Ganghui.
“We need professionals to work on the advanced pulp lines and we have also attracted some key personnel from the APP Jinhai mill, to use their talents in technical and management areas,” says He Ganghui.
The future
Hunan Tiger Forest & Paper secured bank loans to fund an RMB 4.35 billion ($637 million) greenfield pulp mill from Hong Kong-based private-equity firm, Affinity Equity Partners, early last year.
Hunan Tiger’s wholly owned subsidiary Hunan Juntai Pulp & Paper operates the new pulp plant. But its ownership is expected to change soon. Hunan Tiger’s associate Yueyang Paper has decided to acquire 100% of Hunan Juntai for RMB 1.36 billion ($199 million).
Shareholders of Yueyang Paper, whose A shares are listed on the Shanghai stock exchange, have given the move the green light. The deal is still subject to approval by the Chinese government.
Hunan Tiger, a state-owned firm, holds 22.36% of Yueyang Paper, which has five machines at its mill in Yueyang city, Hunan province. These are capable of producing newsprint and other mechanical grades of paper and have a total capacity of 400,000 tonnes/yr.
Yueyang Paper is also building a greenfield mill in Yueyang city, which will house two printing paper machines. Start up is scheduled for the third quarter of 2009.
Andritz will provide a 550 tonne/day fiberline, which will process US sorted and mixed office paper collected in China into deinked pulp with a quality comparable to market pulp (with brightness of up to 82°). The pulp will be used to make various grades such as environmentally friendly copy paper and premium offset printing paper.
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