Operation Report: Santher aims to lead

Brazilian group Santa Therezina (Santher) is starting up what supplier Metso calls “the most advanced tissue machine in South America”. Elisangela Melo reports

Brazil has been growing fast. It is the 10th economy in the world. Initiatives from the private sector and efforts by the government have encouraged foreign investors to choose Brazil as a prime investment option, as well as providing incentives for investment from within the country’s borders.

The country’s climate is ideal for eucalyptus and pine plantations, that grow much faster than in northern hemisphere countries. This has helped boost Brazilian pulp production, which has averaged growth of 7.6%/yr, with paper not far behind, at 5.7%. According to Bracelpa - the Brazilian pulp and paper association, in 2008 the country made 12.8 million tons of pulp and 9.15 million tons of paper and board, of which 850,000 tons was tissue paper.

Growth at Santher - Fábrica de Papel Santa Therezinha - has closely followed the market. The company was founded in 1938. The annual volume of paper produced in its four units is approximately 200,000 tons, including toilet paper, facial tissue, napkins, female absorbents, towels, special papers and AfH. Its main brands are Personal, Snob, Santepel, Kiss and Sym.

LATEST TECHNOLOGY

To maintain market share, the company recently started up a new tissue machine with Metso’s latest technology, Advantage DCT 100. According to Francisco Barel Jr, Santher’s Supply Chain Director, this investment will not only allow it to increase production volume, serving better the current demand for its existing scope of products, but also to launch new high quality products thanks to the latest technology.

At the beginning, the new production will go mainly to the local market, but exports to neighbouring countries are also foreseen.

Santher decided on Metso equipment in April 2008. The decision was taken, Barel said, because of “productivity, technology, efficiency, and important savings. The technology offered by Metso was the added value that led us to choose the DCT Advantage equipment.

“Metso and Santher understood that, as both companies are leaders in the segment, it represented a natural and strong partnership. Santher has started this phase of investments betting that an effective, reliable and ethical partnership can reinforce its leadership in the markets already achieved, as well as leading it to reach new markets.”

According to Metso, the Advantage DCT 100 concept presents many technical differences in comparison to the standard models of tissue machines. They include: the sturdy framing of the forming section is either of solid stainless steel or clad with stainless steel up to the Yankee area. All components and framing are designed to ensure accurate and minimum vibrations at high speed. In this way, wire and felt rolls are large in diameter and thus give a trouble free operation. The machine is designed to minimize the dust and mist problems normally associated with highspeed tissue manufacturing. Unique, patented, dust systems are applied at critical points. Shields are designed to contain the mist inside the machine framings.

“It is important to note that while the new DCT platform is standardized compared to previous designs, it is still based on proven Metso technology and experience. At the same time as we were creating the overall DCT platform, we were also developing many of the new components that make it so successful. All models are equipped with the OptiFlo II TIS headbox, Advantage Air Cap dryer hood and Metso Yankee Dryer, Soft Reel and the Wet Dust removal system,” the company says. The Santher’s tissue machine will have a trim width of 2.7 m, an operating speed of 1800 m/min and a daily production of up to 112 tons of high-quality facial, bathroom tissue and towel grades based on virgin pulp.

Metso’s scope of delivery comprised a complete Advantage DCT 100+ tissue machine equipped with na OptiFlo II TIS headbox, a 16-foot Yankee cylinder, an AirCap Yankee hood and stock preparation equipment including OptiFiner conical refiner, OptiSlush pulping equipment and OptiScreen cleaning and screening technology. Metso Automation supplied a metsoDNA DCS system, drive controls and Paper IQ quality controls. The delivery also included services for installation and start-up of the machine. Metso operates with manufacturing excellence centers for the advanced technology parts of the machine that are considered essential for the high efficiency of operation. For this reason, some parts of the machine, such as Yankee cylinder, headbox, suction roll and air cap were imported from Metso Sweden, Finland and Italy. All of the other parts as well as the pre-assembly have been carried out by Metso Brazil: machine frames, walkways, stretchers, guides, bearing housings, rails, air system ducts, rolls, doctors, showers, separators, etc... The project was tackled on two fronts: machine manufacture was Metso’s responsibility; the civil project - where the new machine will be installed in Bragança Paulista city – was handled by Santher. Technical Features Headbox: The OptiFlo II Headbox produces an outstanding formation particularly important for low basis weight facial tissue: Same formation at higher consistency, up to 20% reduction of flow compared to earlier technology, thus giving significant energy savings. In the slice chamber, turbulence and layering vanes are used. These vanes are tailor made from composite material. The free jet length can be adjusted as short as 160 mm to achieve a very uniform sheet. The rigid design of solid stainless steel ensures stability and no deflection at high pressures required to run at high speeds. The Headbox slice lip opening is adjustable on the run with screw jacks from the side of the Headbox. This adjustment can be made with a remotely controlled motor as well. Yankee cylinder: The large (16 ft) Yankee allows more drying on the cylinder than a smaller Yankee, so that less gas and electricity are needed in the hood. Ample drying capacity also allows the mill to reduce nip load and increase bulk when making premium quality tissue. Apart from high drying capacity and lower drying cost, a large Yankee also has longer intervals between grinding. The Yankee shell is made of a special cast iron alloy, Class 60, which combines hardness (long life time) with high heat transfer (lower energy consumption). The U-shaped grooves give by far the best heat transfer and uniformity compared to other designs in the market. The design used at Santher incorporates new condensate headers with pick-up on both sides. This gives a more uniform heat transfer, better coating control and less deformation of the shell coming from uneven temperatures. Yankee hood: The high temperature hood (up to 510°C) is of a new design with a curved, automatically washable outside to minimize dust accumulation. The new patented solution not only reduces fire risk but also greatly improves the working environment. All Advantage AirCap internals are made from stainless steel for the first 30 graus of wrap followed by Corten in the remaining part. The AirCap is especially designed to avoid distortion influenced by the high temperatures by allowing a sliding arrangement for the blow boxes.

The wet-end section is divided into two sections where profiling is made in the lower half only to ensure full drying capacity in the other half. The hood has dampers for accurate and narrow moisture profiling. The Advantage AirCap can be equipped with an automatic moisture control based on the feedback from the QCS system.

Sheet stabilizers & tail threading: The machine is equipped with all necessary safety equipment such as entrance prevention into moving areas and ingoing nips, etc, in accordance with prevailing international and European CE marking regulations.

The sheet is supported by friction-free sheet stabilizers that generate no dust, which are essential for running at high speed.

A dust collecting enclosure covers the dry end of the machine. Inside the enclosure, a patented wet dust removal system uses water for collecting and removing the dust. This eliminates risk of fires in the dust system; it increases uptime by reducing the chance of plugging; and it also allows for a water hose to be used for cleaning the dry-end area.

The tail is automatically threaded to the reel with air tubes.

Reel-up: The reel is of a pneumatic design with low-friction bearings and nip load control via a closed loop to allow stable operation high speed with accurate control of the winding parameters and possibility to run large diameter parent rolls.

The primary arms are equipped with hydraulic relief cylinders to control the linear load, while the primary arms clamp the reel spool. This gives better runnability and allows use of the paper produced in the primary arms, so there is overall less winding loss.

The reel section is equipped with a weighing station before the roll release and with overhead storage and automatic loading of new reel spools.

DCS system: metsoDNA is the automation platform of the new Santher PM12. Almost the whole machine, from stock preparation to reel, will be controlled and operated by the operating stations of a unique system. In addition to controlling the process signals in the DCS, metsoDNA also combines the functions of the drive controls and of the quality control system.

Drive controls: The dDrive controls, fully integrated to Santher’s machine automation system, represent a new tool for the pulp and paper market. Earlier systems did not have integrated controls. Instead, there were two products, the drive control and the DCS, connected through communication links, what made the solution complex and inefficient. The systems integration improves control and safety.

Control Quality System: The quality control system PaperIQ Select was launched in 2008 and represents a milestone in the evolution of this kind of system, according to Metso. In addition to the standard controls, it brings an intelligent scanning system that analyzes and prioritizes the adjustment of web properties. Santher expects it will be a useful toll for its machine operators.

CUSTOMER:SUPPLIER RELATIONS

According to Barel, the integration has been very positive. “Customer and supplier have been sharing experiences and achievements; they are well connected, focused and working closer - what make them to feel that it will not be the only project together!”

Rui Stefanini Jr, Metso’s Senior Manager - TBL, said that the relationship is very good. It has helped that from the start Santher set up a technical team with autonomy, flexibility and knowhow about all process areas. As a result, the time spent on decision-taking was minimized. All project details were discussed with a single group encompassing all the necessary areas of expertise. From Metso’s side, it was also important to define in each Metso unit that is participating of the project, a technical person responsible for both technical and commercial aspects in order to create fast and effective communication.

“Santher’s expectations are really big. Santher believes that it is not only acquiring a new paper machine, but also starting up a new phase in its winning history, where the leader’s power must be linked to an attitude of excellence and quality in all aspects, whateveter processes, products, attitude and commitment. It means, to be bigger must be always linked to be better. We had started a phase in that we must do more, better and faster,” concluded Francisco Barel.