Gebr Pfeiffer Convention 2012

Over 150 delegates gathered on 21-22 June at the Gartenschau Convention Centre in Kaiserslautern, Germany, for the Gebr Pfeiffer Convention 2012. During the two-day conference, grinding experts Gebr Pfeiffer presented the latest trends in milling technology and offered state-of-the-art, energy-saving solutions.

After the welcome address from Otto Jung, retiring Executive Board member at Gebr Pfieffer, Executive Board Member Gerold Keune provided a fascinating overview of the company’s history. Established in 1864, the family-owned Gebr Pfeiffer has since remained at the forefront of grinding technology in the cement industry. From 2000, the company spread its wings internationally as it established an office in India, where it has gained a 54 per cent share in the vertical roller mill (VRM) market, according to Mr Keune. This expansion move was followed five years later by the creation of a base in the USA. Last year, it launched the MVR 6700 C-6, the world’s largest cement mill, responding to the ongoing trend for increasingly-larger mills in the cement industry.

Latest grinding trends

Dr Robert Schnatz, member of the company’s Executive Board, informed participants of the latest grinding trends in the cement industry. While in 2009-11 around 58 kiln lines were sold in the cement industry (excluding China) with capacities ranging from 1000-12,000tpd, around three-quarters of these lines were in the 3000-6000tpd capacity bracket. However, as producers look to improve their operational efficiency, they require higher-capacity grinding facilities. Although the worldwide recession impacted the market considerably with sales of grinding mills falling across the board, last year the market noticeably started to recover, particularly in the VRM segment, which is proving an increasingly popular choice. VRMs now make up around 75 per cent of mill systems sold, according to findings by a OneStone Research report commissioned by Gebr Pfeiffer.

Moreover, Dr Schnatz noted other trends, including towards more (semi-)turnkey contracts as remote cement grinding units are established, away from the clinker manufacturing plants. However, the way producers perform their grinding operations has also brought changes. “One raw mill feeds one kiln for all plant sizes and as a result, an excellent reliability/availability of the raw mill is needed,” he highlighted in his presentation. Furthermore, the use of moist additives in the pozzolanas and slag demands the extra step of drying during the grinding process.

Alternative milling solution

Klaus-Peter Lukas then went on to present the company’s MPS and in particular, its MVR mills with MultiDrive® as an alternative to milling solutions currently available on the market. He showcased the mill’s benefits, including its modular drive design, symmetric wear parts and space-saving twin support.
Mr Lukas also compared the one-mill solution offered to a two-mill configuration and highlighted a cost-saving of around 25 per cent as the former has a smaller footprint and building volume.

In addition, he continued to point out the higher availability of the single MVR when compared with the two MPS set-up. Its active redundancy – with up to six grinding rollers and six drive modules – enables operation to continue even if a roller or drive module is under maintenance. Moreover, a hydraulic system for operation and maintenance avoids the need for extra equipment to swing the rollers out of the mill.

MultiDrive® success

Andreas Halbleib and Rudy Blum of Holcim told attendees of the cement producer’s journey to solve its persistent issue of reducer failure, particularly with large gearboxes, on its VRMs. They gave testimony to the success of Gebr Pfeiffer’s MultiDrive® concept at the Val de Seine, France, cement plant, where Holcim first implemented the design. The cement producer has since gone on to include a single VRM and the MultiDrive® concept in its specifications for the company’s Barroso plant in Brazil, which houses the world’s largest vertical roller mill, the 450tph Pfeiffer MVR 6700 C-6. The mill is part of a wider EP project, awarded to main contractor Cemengal, who will be responsible for the total design and supply of all equipment except the VRM.

Furthermore, Cement Australia’s grinding station at Port Kembla’s sea terminal will also draw on Gebr Pfeiffer expertise as it will see a MVR 6000-C6 mill installed, rated at 208tph for OPC and 190tph for GGBFS. As with the Barroso order, the overall project will be carried out in co-operation with Cemengal, who were awarded the EPC contract for the entire Port Kembla unit.

Dr Caroline Woywadt subsequently highlighted the performance of MVR and MPS mills with and without MultiDrive® in several cement plants such as Lukavac in Bosnia-Herzegovina (after 11,000h of operation) and France (after 3000h of operation), in her presentation “20,000 hours operation experience with MVR mills and MultiDrive®.”

After lunch, guests were given a guided tour of the company’s headquarters in Kaiserslautern while in the evening a gala dinner provided an informal setting for discussion and relaxation. 

Theory put into practice

Friday morning brought a wide range of case studies, enabling delegates to gauge the versatility of the Pfeiffer range of grinding mills. Head of process engineering Dr York Reichardt provided information on the grinding of very moist and sticky raw material at Mordov Cement, Russia, where the grinding mill is required to comminute chalk-based raw material with a moisture content of 26 per cent. The system uses heat from the gas turbine, kiln gases and hot gas generator to dry the material in an energy-efficient way. Today, the MPS 5300 B mill at Mordov successfully runs up to 400tph of feed to the plant’s third kiln.
Wolfgang Stoiber of Lafarge presented the operating results of a large cement VRM at the company’s Kujawy plant in Poland.

Ruediger Sonnen highlighted HeidelbergCement’s experience of the new coal grinding plant at Lixhe, Belgium. Gebr Pfeiffer delivered the new MPS 225 BK and a SLS 1800 BK classifier to the plant in January 2011. Less than four months later, the equipment was successfully commissioned.  

Gebr Pfeiffer’s capabilities also extend to the gypsum and lime industries. For instance, Michael Hahn took delegates further afield, by detailing Cementos Progreso’s second lime hydration unit at its works in Guatemala.

Food for thought

Dr Robert Schnatz gave participants food for thought with his comparison of grinding systems for the cement industry. He focussed on the significant energy savings that could be made with VRMs, both in terms of raw material grinding and cement grinding, when compared with the conventional ball mill and high-pressure grinding rolls. Combined with high drying capabilities and low investment costs, he concluded that MVR and MPS VRMs proved an ideal choice for a wide range of cement industry grinding projects.

Article first published in International Cement Review, August 2012.