Set among thickly bamboo-forested hills, interspersed by valleys with clear running streams and impressive waterfalls, the Guizhou Chitianhua Paper Industry’s tissue mill is one of the most environmentally important production facilities in the rapidly growing Taison Group. Andritz recently supplied the mill with two PrimeLineST tissue machines, including complete stock preparation to keep the growth on track.
Situated quite some distance away from any mass industrial developments or highly populated areas, the Guizhou Chitianhua tissue mill is near the town of Chishui in southwestern China. The Taison Group has a number of major board and tissue production facilities in China, and has a growth plan that will see it become one of the nation’s top five producers by 2020. The general manager at Guizhou Chitianhua, Wang Hongwei, says, “The Taison Group will reach a total capacity of 5 million metric tons in 2018; however, with our ongoing expansion plans throughout the group, we will reach 8 million metric tons a year by 2020, making us one of the largest producers of paper, board, and tissue in China.”
The group is not limited to domestic expansion; it also recently acquired Swedish company Nordic Paper Holdings, which includes four specialty paper mills in Scandinavia.
Tissue is of major importance to the group’s expansion plans, as China sees an unprecedented growth in demand. According to Wang Hongwei, consumption of tissue is growing at around 6 percent per year.
The Chitianhua mill was originally owned by the Chinese government, which was struggling to make it profitable producing printing and writing paper using bamboo as raw material. The mill was sold to the Taison Group in 2015, and was immediately converted into producing tissue using bamboo as the main fiber source.
“This is the perfect area for a mill producing tissue out of bamboo, as we have a virtually unlimited source of raw material,” says Wang Hongwei. “We are producing bamboo pulp here at a full capacity of 250,000 metric tpy, consuming some 1 million m2 of local fiber which comes from land we rent from the government. Bamboo is a fantastically sustainable source of fiber as basically the more you cut, the more it grows.”
Legend has it that in 1769, Li Litai, a migrant from Fujian province, brought four bamboo plants to the town of Chishui, and 100 years later there was total forest coverage. The prolific plant species now provides some 200,000 local inhabitants with a way to make a living, making the Chitianhua mill very popular in the area. In fact, the Chinese government has awarded a special certificate to the mill in recognition of social and environmental efforts it has made since tissue production began here.
IDENTICAL TWINS: TM 5 AND TM 6
When the Taison Group took over the mill, Andritz was chosen as supplier for two identical tissue machines, PrimeLineSTs with design speeds of 2,000 m/min and a width of 5.6 m each. “Andritz is clearly seen as the No. 1 supplier by the Taison Group,” says Wang Hongwei. “The management at the group wanted the very best and most modern machines, which is why Andritz was chosen. Another reason it was selected was for its vast experience in producing tissue out of bamboo pulp.
The mill uses about 70 percent bamboo pulp as raw material with the other 30 percent made from softwood market pulp. Along with the two PrimeLineST tissue machines, Andritz also supplied two complete stock preparation lines. Wang Junling, Andritz (China) Pulp and Paper Technology startup engineer, says, “Using bamboo as a raw material to produce tissue throws up a number of challenges regarding stock preparation, in particular, regarding refining. Bamboo pulp has shorter fibers and is therefore weaker than wood fiber. To make sure we meet the raw material requirements at the mill, TwinFlo-Strong refiners with higher motor power, lower flow, and matched refiner fillings were installed.”
The tissue machines were the first of their kind delivered in China to combine high performance PrimeDry Steel Yankees with steam-heated hoods. The yankees are made entirely of steel and have a diameter of 20 feet—among the largest in the world for tissue. Both yankee cylinders were manufactured at the Andritz steel yankee business center in Foshan, China, which offers customers state-of-the-art manufacturing, local field service, and quality management.
The maintenance of steam-heated hoods challenged the efficiency of tissue machines in the past. To solve this problem, Andritz delivered a new design: The PrimeDry Hood ST is equipped with double-width nozzle boxes for easy maintenance, where each nozzle has its own cleaning port. The hood offers optimized impingement pattern and an open area for efficient drying at minimum dust accumulation. Along with the stock preparation line and tissue machine, Andritz also supplied automation with its tailored system for tissue PrimeControl, including DCS and QCS, as well as all erection and commissioning services.
Contracts were signed for TM 5 and TM 6 in December 2015, and commissioning took place respectively in July and September 2017. TM 5 started up in August 2017, followed by TM 6 in October.
Hongwei Sheng, Chitianhua’s tissue production expert, has already had a lot of experience with Andritz machines at the mill, and was brought in specially to oversee the startups and successful continuing operation of the two tissue machines. Sheng says, “I was previously at our operations in Hengan, so I already had a lot of experience with starting up and operating PrimeLine machines, also with yankee cylinders. “What was new for me was the incorporation of the steam-heated hoods on TM 5 and TM 6 and, of course, the bigger sized yankee at 20 feet in diameter.”
Sheng reports that the startup of both machines went very well and according to plan, “This is the biggest tissue project in the Taison Group, and is a very important one for us—it had to go right! These machines are basically identical and we successfully started up TM 5 in August last year, quickly followed by the TM 6 in October.
“We are now producing 260 metric tpd of the highest quality tissue in the group, with both machines producing 130 metric tpd each,” adds Sheng. And what difference has the extra-large yankee made, added with the steam heated hoods? Sheng says, “As well as maximum output and high-quality products, energy consumption is a very important issue for us. Andritz suggested that with the combination of the steam heated hoods and the increased size of the yankee, we could get more capacity, longer drying time, and reduced energy costs. And yes, so far we really are noticing a clear difference in comparison to other lines in the group.”
Wang Junling says of the startup from the Andritz point of view: “This project was a challenging one, as the customer demanded a quick startup, so everyone had to work very hard to make the target. The PrimeLine technology was also new to a lot of the people at the mill, so there was a steep learning curve. “However, starting up the two machines at once proved to also have advantages. What we learned on the startup of TM 5 meant that we were able to start up TM 6 four days ahead of schedule!”
ONWARD AND UPWARD
General manager Wang Hongwei says that there is still a lot of further scope for expansion at the mill, “Our bamboo pulping operation is running at full capacity of 250,000 metric tpy and we are only using half of that pulp on TM 5 and TM 6; the rest of the pulp is sold onto the market. Our plan is to use all that pulp at this mill for our own products, making us even more of a cost leader and capturing even more market share. “Andritz, of course, will also be joining us in our success!”
To underline the Taison Group’s expansion plan, it has already ordered another four tissue lines from Andritz.