3rd Global Slag Conference and Exhibition 2007
19-20 November, Istanbul, Turkey
Reviewed by Dr Nino Mancino, conference convenor
Istanbul – where East literally meets West – was the venue for the third Global Slag Conference and Exhibition 2007. Over 150 delegates from 34 countries met at the Swissôtel The Bosphorus – a truly multinational gathering of slag experts in an appropriately impressive setting. The conference was well supported by the Turkish Cement Manufacturers Association (TÇMA), which is celebrating its 50th anniversary in 2007. In fact there was a distinctly Turkish flavour to the event, with almost 40 delegates from the host country in attendance.
A total of 13 papers were presented on a variety of topics, ranging from the Turkish slag and cement markets, a focus on special slag cements and innovations in slag chemistry and handling technology, all delivered in keeping with the stated aim of the symposium – adding value to slag.
Bus tour of Istanbul
A bus tour of Istanbul took place on the morning of Sunday 18 November, and was a perfect way of meeting some of the delegates in a relaxed setting. The three-hour tour comprised of a trip to the absolute must-sees of Istanbul; the Blue Mosque and the Hagia Sophia. The former is a quite spectacular building, composed of several interconnecting domes and a total of seven exquisite minarets, a record for a mosque anywhere in Turkey. Outside of the Blue Mosque lies the Hippodrome, what was once the ancient setting for chariot rides. The Hippodrome contained several ancient obelisks (one dedicated to Roman Emperor Constantine, the man whose name graced the city in its former guise, Constantinople). The other highlight was a short tower of bronze, made from the melted-down weapons of the Persians defeated by the Greeks in the 5th century BC!
Next on the list was the Hagia Sophia, which was firstly a Christian church, and then converted into an Islamic mosque after the Ottoman forces conquered the city in the 15th century. Today the Hagia Sophia is a museum, and fortunately, most of the artwork from all of its previous existences is preserved. As a result, Christian iconography stands shoulder-to-shoulder with Islamic calligraphy in one building. Unique indeed.
Day One
On the opening morning there was a sense of interest and eager anticipation. Delegates arrived from 8.30am onwards, making their way into the impressive auditorium for the opening welcome, provided by conference chairman Dr Robert McCaffrey.
The first paper was given by Metin Usta, project manager for Erenco Eregli Engineering, Management and Consulting Services. The title of Mr Usta’s talk was ‘A short history of blast furnace slag in Turkey’, which gave an overview of the production of granulated blast furnace slag (GBFS) at the Erdemir, Isdemir and Kardemir iron and steel plants, including technical details and schematics. Mr Usta also provided forecast production volumes of GBFS in Turkey; in 2008 total slag production is expected to be 1.93Mt/y, and is forecast to reach 2.34Mt/y by 2012.
The second paper was delivered by Sang-tae Cha and Sang-yoon Oh, both of Korean firm Ecomaister Co Ltd and co-authored by Hadi Sadrpour, President of Iran Gostaresh Technology Management Institute. Ecomaister has pioneered the technique of slag atomising technology (SAT) to generate spheres of steel slag – called Precious Slag Ball, (PS Ball) – that are uniform in size and possess high strength. PS Balls are employed in a wide variety of applications, including as abrasive materials, roofing granules, filtration media, and as aggregate filling materials for construction. Ecomaister’s innovative work provides a perfect example of ‘adding value to slag’, a substance that has for too long been typecast as waste, when in fact it is a highly valuable material in its own right.
The next event to take place in the conference hall was a new innovation called ‘meet the delegates’. This session enabled the delegates to stand with microphone in hand and state their name, company, what they do, and their reason for being at the conference, including who they would like to speak to. The introduction of this format proved highly popular, allowing much more efficient networking during the many coffee breaks. A total of three ‘meet the delegate’ sessions were carried out over the two days of presentations, giving all the delegates a chance to participate.
Next to take centre stage was Barry Woodbine of Aumund Group, who gave a slick presentation on the range of bulk materials handling and conveying equipment offered by Aumund. The need to manage the storage and transportation of bulk materials is vital – after all, what is point of trying to find an application for slag if those who produce it cannot store and move it properly? Of particular interest in Mr Woodbine’s talk was a description of the Samson Surface Feeder. The Samson Surface Feeder is designed in such a way that materials are deposited from road trucks into the feeder in a controlled way, with little or no dust. This design feature offers a clear environmental advantage.
Our next speaker was from Poland – Miroslaw Karbowniczek of the AGH University of Science and Technology. Mr Karbowniczek’s research is based on the non-metallic phases of converter slags. He and his team have performed some interesting lab-scale investigations, examining the thermodynamics of the slag reduction process in a mini electric-arc furnace in order to probe the content of key minerals that develop during heating, including CaO, SiO2 and Fe 2O3. The goal is to use these slags as substitutes for Portland cement clinker, and as soil fertilisation media. Initial results are promising, but as Mr Karbowniczek admitted, pilot- and industrial-scale investigations are needed in order to fully assess its potential.
Changing continents, the next presenter was Mr SungMo Seo from POSCO in Korea. Mr Seo gave a confident talk on the stabilisation of basic oxygen furnace (BOF) slag in order to reduce the formation of free lime (CaO) that, via its expansion, restricts its use in various functions. POSCO’s stabilisation strategy is based on slag atomising technology (apparently a popular method in Korea in view of paper two!). Mr Seo and his colleagues have experimented with different pressures and cooling rates to determine the effect on the mineralogy and size of the slag spheroids produced from SAT. Eventually they settled on a method whereby no free lime is detected in the slags, as judged by X-ray diffraction (XRD) and electron microscopy. Intriguingly, Mr Seo and his team were also able to generate slag fibres, which are glassy in appearance and between 10-30µm in diameter. This was achieved by using a high rate of cooling gas, such that the quenching time was greater than the time taken for the formation of spheres. When asked about the utility of these fibres as insulation materials, Mr Seo admitted that this could indeed be a possibility.
Following on from this was Dr Timo Parviainen of Finnish company Outokumpu Stainless Tornio Works. The company produces approximately 380,000t/y of steel slags that are used in Finland as road construction aggregate. According to Dr Parviainen, this means the sparing of precious quantities of natural gravel and sand that would otherwise be mined. Dr Parviainen communicated the results of rigorous testing of these light mineral slag aggregates (LMA), including the results of leaching tests. Finland has very strict leaching limits, and for the slags to be used in this way they must meet demanding criteria, the most critical being the liberation of fluorine into the water supply. Results indicate that use of LMA in test roads has not affected the chemistry of ground water, at least no more than compared to natural gravel-based reference standards. Furthermore, roads constructed using LMA are insulated from frost much better than with normal aggregates. The bearing capacity of roads constructed with LMA is also higher than with commonly used aggregates.
The final paper on the first day was presented by Leksminingsih Dra from the Ministry of Public Works in Indonesia on ‘The performance of asphalt mix containing filler slag for heavy trafficked roads.’ Ms Dra’s team set-up a series of four aggregate mixtures – 100% asphalt, plus asphalt with filler slags with the following percentages; 5%, 7.5% and 10% by weight. On these samples the research team performed a series of tests to assess their feasibility as road aggregates, including elasticity modulus, Marshall parameters, falling weight deflection and pavement condition surveys (PCS). Overall, the results showed a positive correlation between slag content and road stability for roads defined as ‘heavy traffic roads.’
Gala Dinner and Global Slag Awards 2007
The Gala Dinner was, put simply, a memorable event! Almost 100 people attended the gala dinner, which consisted of a cruise down the Bosphorus on the ship Swissôtel Istanbul II. Delegates were greeted with a welcome wine and cocktail reception on deck. Making our way to the inner sanctum of the boat we were treated to a sumptuous, buffet-style array of Turkish and Mediterranean fare. One word – delicious.
After dinner, the Global Slag Awards for 2007 were presented. First prize in the category of Global Slag Production Innovation of the Year went to Ecomaister, chiefly for the invention and application of PS Ball technology. Sang-tae Cha collected the award on behalf of the Korean company, and was clearly delighted, as were his colleagues.
The next award was Global Slag Usage Innovation of the Year. The Global Slag editorial board had no hesitation in awarding this year’s trophy to Donal O’Riain of Ecocem. Ecocem has led the way in developing slag cements that are environmentally more benign that conventional Portland cements. Ecocem was noted for its tenacious marketing campaign and its sustained efforts to change the norms and specifications relating to slag cement use in the EU and beyond.
The third prize was awarded to Barry Woodbine on behalf of Aumund for the Global Slag Equipment Innovation Award 2007. Aumund has managed to create an outstanding reputation for the handling and conveying of bulk materials, including slag, and are worthy winners.
The fourth and final prize was awarded to Paul Ratcliff of Holcim for Global Slag Personality of the Year, in recognition for the huge amount he has done in terms of promoting the use of slag in the cement industry. Award-presenter Dr McCaffrey described Mr Ratcliff as modest and self-effacing, who would be the first to deny that he deserved such an award. In his short but pithy acceptance speech, Mr Ratcliff implored the audience to think of a different, less controversial name for slag!
Most people would think that after all that drama, the evening would end there. Not so. Last, but by no means least, and in keeping with the finest traditions of the host country, we were treated to a belly-dancing performance that left several delegates’ proverbial jaws on the floor. Needless to say, cameras previously hidden from view appeared magically to record the performance.
Day Two
Delegates arrived at 9am sharp to start the second and final day of presentations. Kicking off was Ünal Öner, Assistant General Manager (Technical) of Adana Cement Company, itself part of the Oyak group of cement companies. Mr Öner gave us an overview of cement and slag cement capacity in Turkey. CEM III slag cement production is based around two main sites – Bolu Cimento and Adana Cimento, in the north and south of Turkey respectively. Sales forecast for CEM III cement from both these sites is expected to reach 3Mt in 2009, and will be mainly exported to foreign markets.
The next presenter, with a talk entitled ‘Turkish Cement Sector and TÇMA’, was delivered by Mrs Çaglan Becan. A member of the Turkish Cement Manufacturers Association since the 1970s, Mrs Becan gave a very good synopsis of the state of the Turkish cement sector, and a brief history of the TÇMA and its activities. The TÇMA is the formal representative of Turkish cement producers and, as was alluded to earlier, was founded in 1957. It acts as a link between industry, the Turkish Government and the public. As well as being actively involved in promotional work, the TÇMA also analyses technology and quality problems, and performs R&D activities.
According to Mrs Becan, growth in the Turkish construction sector reached 19.4% in 2006, with the cement industry playing a key role. Turkey has 60 cement plants, and employs modern, up-to-date technology in all its facilities, in keeping with EU norms. In 2006, clinker and cement production capacity was 42.6Mt and 70.7Mt respectively. According to Mrs Becan, Turkey was the largest exporter of cement in Europe by sales volume in 2006, reflecting the high esteem in which the Turkish cement is held. However, the sale of slag cements (in particular CEM III) has dropped from a high of almost 7% of total cement sales in 1997, stabilising to just below 2% in 2006. Also mentioned was the fact that it is widely anticipated that Turkey will gain admission into the EU within the next decade, meaning that the Turkish cement industry will then be subject to the EU CO2 Emissions Trading Scheme.
Also representing the TÇMA as Head of the Concrete Department was the next speaker, Mr Bahad?r Erdo?an on the subject of the sulphate resistance of CEM III slag cements. Concrete durability is inhibited by the attack of sulphate ions from surrounding water sources, resulting in expansion, cracking and loss of concrete strength. Mr Erdo?an described R&D work carried out by the TÇMA at the Adana Cimento plant, which uses GGBFS in the concrete mixture and compared its resistance to attack by sulphate ions relative to ordinary Portland cement and special Sulphate Resistant Cement. Overall their research showed that the incorporation of GGBFS in the cement mixture caused an increase in concrete strength due to a decrease in concrete permeability. This work has important implications for the promotion of slag cements, not only in terms of possessing a smaller carbon footprint, but also as being technically superior to concrete prepared from ordinary Portland cement.
For the eleventh presentation, Dr York Reichardt of Germany’s Gebr Pfeiffer AG gave an authoritative demonstration on the slightly different– but no less important – theme of slag grinding. After a brief history of Gebr. Pfeiffer since its inception in 1864, Dr Reichardt introduced some case studies from around the world on the use of its MPS range of vertical roller mills, noting that in each of these cases the production and grinding performance has exceeded the requirements made by the client cement producer. These include optimised production rates and power consumption. Dr Reichardt made the very important point that grinding is only as effective as the quality of the conveying system used to transport the material into the mill, since vertical roller mills need a constant feed of material for optimum performance.
The penultimate presentation was delivered by Francesco Pezzotti of US-firm Bulk Materials International, who highlighted three case studies in which the benefits associated with replacing traditional cement raw materials with steel slags was assessed. In all three examples the effect was to drastically reduce emissions of CO2 and drive down the cost of the final cement. Mr Pezzotti admitted that the driving force for this is financial, since the US has no carbon trading scheme in place unlike, for example, in Europe.
The thirteenth (and not unlucky) talk was quite simply the perfect way to end the programme of presentations. Gary Hunt and Martin Popham of Celtic Cement Technology Ltd produced a moving and inspirational tour de force, showcasing the considerable work that they and their colleagues have done to produce slag-based cements. Mr Hunt started by presenting technical information relating to the rigorous analytical testing regimen developed to ensure product quality. After a thought-provoking video that reminded everyone of the dangers of global warming, Martin Popham then gave a brilliant demonstration of how Celtic Cement’s technology is eco-friendly, the highlight being the revelation that the power source used to produce their special slag cements is derived from plant matter. Celtic Cement’s approach and commitment to sustainability is laudable. They are congratulated on the brave steps they have already taken to cause a paradigm shift in the industry’s perception of slag cement.
The conference chairman then began an interesting 30min panel discussion on a variety of themes, including the future of slag cement and the commercial importance of the re-branding of slag. Several speakers stood to voice their opinion. Overall, the view expressed is that the future of slag as a valuable by-product is healthy, and it is anticipated that exciting developments are only around the corner.
Farewell Cocktail Party
The farewell party took place in the charming Swiss Chalet. A healthy number of delegates took part, partaking of the never-ending selection of canapés and drinks on offer. Dr Robert McCaffrey thanked all of those who helped to make the event such a success, not least conference organiser Saija Nakari, who did a sterling job in bringing everything together. All that was left was for the announcements of Best Presentation and Best Exhibition Awards, both of which were chosen by the delegates. The latter award was given to Ecomaister. It certainly was an exhibition stand with a difference, with the Korean company brining samples of its PS Ball material in neatly packed ampules. The Best Presentation award went to Martin Popham and Gary Hunt of Cenin Cement for their excellent presentation, followed by Çaglan Becan in second place and Sang-tae Cha in third position.
Field Trip
The field trip for the 3rd Global Slag Conference 2007 involved a visit to the Bolu Cimento plant, followed by a trip to the Erdermir Iron and Steel plant in Eregli, both in the north of the country. Arriving at Bolu Cimento after a long and eventful journey the delegates were treated to a very generous four-course lunch, followed by an informative visit to the plant and quality control laboratories.
The next leg of our journey took us to the Erdermir Iron and Steel plant at Ere?li. We arrived just as a large number of workers were ending their shift, prompting odd looks from those who were surprised to see a tourist bus enter a steel plant at 5.30pm! Our hosts at Erdemir were extremely welcoming, providing us with special protective equipment on our journey around the plant. We saw the main blast furnace area, including the spectacular site of molten iron cascading at a furious rate into collection pits. The delegates also had the opportunity to see the hot and cold pressing areas.
Summary – Turkish delight!
The 3rd Global Slag Conference 2007 was undoubtedly a huge success. The feedback we received via the questionnaires and informally in conversation were extremely positive. The editorial board are determined to make the 4th Global Slag Conference 2008 in Strasbourg an even greater success. From Istanbul we bid you a fond farewell, and we look forward to seeing you all (plus many new delegates) in Strasbourg in 2008!
