NEWS

(07/12/2021 / sbr)

Andritz: Major pulp production technologies and key process equipment for the world’s largest DP pulp mill

International technology group Andritz is supplying major energy-efficient and environmentally friendly pulp production technologies and key process equipment for Bracell’s Project “Star” in the city of Lençóis Paulista, São Paulo state, Brazil.

The mill features two flexible, environmentally friendly hardwood fiberlines for a capacity of 2.6 – 2.8 million tons/year of bleached kraft pulp or 1.5 million tons/year of dissolving pulp, which is used as raw material for the production of viscose. Andritz was awarded this contract in July 2019, and start-up is scheduled for August 2021.

Bracell, one of the largest global producers of dissolving pulp and special pulp, is finalizing its Project Star work to expand the company's operations in Lençóis Paulista, in the interior of São Paulo state. The plant will start operating in mid-August 2021, with a production capacity of up to three million tons per year. The project is outstanding due to its sustainable DNA, featuring advanced technology, operating entirely free of fossil fuel, and using renewable raw materials to create biodegradable products.

According to Pedro Stefanini, General Director of Bracell SP, the technologies applied in Project Star aim to make production in the mill even more sustainable. “The project is much more than a pulp mill. It is the future of the bioindustry. Here we will have the largest and cleanest recovery boiler in the world, equipped with state-of-the-art technologies that are not yet used on an industrial scale in the region,” says Pedro Stefanini.

Andritz is providing – on EPCC (Engineering, Procurement, Construction and Civil Construction) basis – four of the six most important process islands in the pulp mill:

  • A complete Wood Processing Plant using Andritz’s proven technologies and including four chipping lines, two stacker-reclaimers, eight chip screening units, biomass handling with two BioCrushers, and biomass storage. Each chipping line for eucalyptus processing includes Andritz’s unique, horizontally fed HHQ-Chipper (EXL model), ensuring high capacity and optimum chip quality. Woodyard operation is enhanced with state-of-the-art Metris – Andritz digital solutions, featuring artificial intelligence and digital sensors. The plant includes ChipperEKG, stone detection, the ScanChip chip analyzer, and a FlowScanner, which measures the density and moisture content of the chips to optimize the fiberline process and minimize wood consumption.
  • A Herb Recovery Boiler with high steam parameters of 101 bar(a) and 515°C to maximize power generation. This is, according to Andritz, the largest recovery boiler in the world, with the capacity to burn total solids of 13,000 tons per day, and it is being equipped with state-of-the-art technologies not yet used in the region so far on an industrial scale. The state-of-the-art boiler will not only make the mill self-sufficient in energy supply but will additionally produce around 180 megawatts of green energy that will be fed to the Brazilian grid to supply roughly three million people with clean energy. The Herb Recovery Boiler features energy-efficient flue gas cooling and feed water preheating technologies to maximize steam production for power generation. It is designed for extended operating periods without requiring wash water.
  • Two environmentally friendly hardwood Fiberlines, for capacities of 2.6 to 2.8 million t/y of kraft pulp or 1.5 million t/y of dissolving pulp, that process certified eucalyptus trees ensure low effluent emissions and also include a chip feed system, LoSolids continuous cooking system with Pre-Hydrolysis Vessel (PHV), screen room and bleach plant as well as Andritz’s DD-Washer technology, ensuring low operating costs, low emissions, extremely high washing efficiency, and excellent fiber quality. The cooking plant for the fiberline is state of the art in the continuous cooking process for production of dissolving pulp.
  • Two innovative EvoDry Pulp Drying Systems for the most energy-efficient pulp drying based on the high-capacity Twin Wire Former technology, with airborne dryers, cutter-layboy and baling lines. The approach flow with cleaner systems ensures homogeneous pulp feed to the subsequent process stage for both types of pulps – dissolving and kraft. The pulp dewatering machine comprises a headbox with dilution control, a Twin Wire Former, and a press section with one combi-press and two shoe presses. The Andritz technology for pulp drying is very well proven all over the world. The Andritz cutter-layboy provides the pulp bales to be further processed in the high-capacity baling lines, where the final pulp bale units are produced.
  • Andritz is also supplying a Non-Condensable Gas (NCG) treatment system that enables safe and environmentally friendly treatment of all types of diluted or concentrated malodorous gases, thus meeting the strictest environmental and social requirements. The gases are collected and eliminated by waste gas incinerator with quenching as well as flue gas scrubbers. The NCG incineration system is based on the “A-Recovery+” concept developed by Andritz, focusing on the use of side streams in the recovery cycle.

Photo: Andritz