Located 75km to the east of Istanbul, Nuh Çimento's 4.35Mt/yr cement plant is the largest in Turkey and is also larger than any single-site cement plant in Europe. It has three kilns, a dominant local position and strong exports to a wide range of locations overseas. It has recently turned to alternative fuels, using dried sewage sludge and refuse-derived fuels (RDF), and also has a waste-heat recovery system, installed by Sinoma of China. Global Cement Magazine recently visited the plant and interviewed plant manager Hayrettin Şener.
Global Cement: "Thank you for allowing our visit to Nuh Çimento today. Can you briefly describe your background in the cement industry?"
Hayrettin Şener: "I have been at Nuh Çimento for around three years. Before that I worked for Akçansa, in almost all of its plants. I started in Çanakkale in 1979 and then moved to the Büyükçekmece plant, when it was Ak Çimento, for 18 years."
"I returned to Çanakkale as plant manager in 1999 and then moved to Çimsa, which now has five plants in Turkey. I moved to Sabancı Holding as a project director and then in 2010 I came to Nuh Çimento."
Raw material
GC: "Could you give our readers an overview of the production process at Nuh?"
HŞ: "In our onsite quarry we mine marl and limestone together. In this area we actually take around 70-80% marl and 20-30% limestone. We take these proportions directly to the plant. Sometimes the calcium carbonate content of the marl is high, in which case we might remove some of the limestone. Conversely we might add a little more limestone if the marl is slightly deficient in calcium carbonate."
Production process
HŞ: "After mining, we have our raw material crushers, two 1500t/hr machines from the old Friedrich Krupp AG, and two 50,000t homogenisation/storage domes. To the mined mixture we add 1-2% iron ore and we may add 1-2% aluminium oxide."
"We have three Loesche raw mills that have a total combined capacity of 900t/hr. Once we have prepared the raw meal, we have three lines. Two of them are KHD Humboldt Wedag kilns and the third one is from FLSmidth."
"The capacity of the first KHD line is 2800t/day, the second line is 3200t/day and the FLSmidth line has a capacity of 7000t/day. In total we can produce around 13,000t/day, roughly around 4.35Mt/yr."
GC: "When did the three kilns come online?"
HŞ: "The first line was 1969, the second was 1971 and the third was 2005. They are operating at around their combined installed capacity at the moment due to good demand. However, recently we had a problemwith a crack on kiln three where it contacts the rollers."
"We have made some repairs to that and it is running at its installed capacity, which is 6500t/day. When conditions were good we had reached up to 7000t/day."
"We have no inventory at present, which is an indicator of the demand that is around us in this area. It's all sold and that means we have to keep producing."
GC: "It sounds like demand is so high that you couldn't shut the kiln for maintenance even if you wanted to. However, is there the risk of a major failure on kiln three?"
HŞ: "We have no inventory, as I said, so we need to operate all of the kilns at the moment. With regards to a failure, anything could happen anywhere in the plant, but we are monitoring that specific crack. We halted kiln three in January 2013 for general maintenance. Obviously we schedule to close the kilns in the winter time, when demand is at its lowest."
"We have four cement mills. The first two are 140t/hr Polysius mills and the third is a 140t/hr FLSmidth design. The fourth one, another FLSmidth mill, is, I think, the biggest ball mill in the world. It can mill 320t/hr."
"Afterwards we have four clinker silos of 250,000t total. We have packing plants by Haver & Boecker and they supply either bulk or bagged cement. We also have our own port. The berth can take vessels of up to 75,000t and it also has a facility to load big-bags for export. We have a road connection under the O4 Highway so that trucks can take material to that facility."
Alternative fuels
GC: "Can you outline the different fuels used at the Nuh Çimento plant?"
HŞ: "Certainly. We burn lignite and petcoke in the kilns as our main fuels. We only started with petcoke in September 2012 in the first and second line."
"Previously in our plant we dealt with alternative fuels by hand but this practice was restricted by new regulations in 2010. To cover this we installed a sewage sludge drying plant in 2009."
"We take the hot waste gases from kiln three and take it to the sludge plant to dry it, but it is only 20% solid material. We evaporate to obtain the solid material and burn it in kiln three. The processed sludge has a heat content of 2500 – 3000kCal/kg. The current capacity is 250t/day of sludge, so the dry solid material rate comes out at around 50t/day maximum. On average we get around 40t/day."
"We have installed a Di Matteo RDF plant / feeding system, which was new in late 2012. It currently provides RDF to line three only. It is fed with mixed refuse from an environmental company that has already removed the non-combustibles from the waste-stream. We started with 1t/hr and slowly increased this to 2t/hr, 3t/hr and reached a full capacity of 5t/hr. It can process 5t/hr when feed conditions are ideal."
GC: "What proportion of alternative fuels does the plant use at present?"
HŞ: "At the moment 3% of our fuel is dried sewage sludge. The RDF plant has a 5t/hr (100t/day) capacity, which is around 5% of consumption on average, a total rate of 8%."
"This currently goes just to kiln three, but once kiln three is stable we will extend to kilns one and two, with installation of a new feeding system. In future when we open up RDF to these kilns we expect to go to around 15% alternative fuels."
GC: "Would you expand the sludge and/or RDF facilities in future or seek to use other alternative fuels to increase the alternative fuel substitution rate?"
HŞ: "Well, in all of these cases it is relatively easy to install such handling and feeding systems. However, sourcing RDF is not so easy in Turkey at the moment."
"We need suppliers at the moment but in the future we will become increasingly confident with RDF and we will likely see the economic benefits as a good reason to go and look for more material. In the longer-term I cannot rule out any alternative fuel. I think that the top substitution rate for this plant in its current configuration would be ~25%."
GC: "What limits the alternative fuel substitution rate at present?"
HŞ: "Assuming that we could find enough material, we would be limited by various regulations regarding emissions and by our own requirements regarding our clinker and cement quality."
"Of course we would like to run the plant with all types of alternative fuels in an ideal situation, but we cannot do this at the expense of our high-quality clinker and cement. We have to take care. We are a cement production plant first-and-foremost, not a waste incinerator."
"The maximum waste consumption at the moment is at Akçansa's Büyükçekmece, which ran at around 20% alternative fuels in 2012, I think. We could get to a comparable position with some new developments."
Other systems
GC: "Are there any other supplementary environmental systems operating at the plant?"
HŞ: "In addition to alternative fuels, we have also invested in a waste heat recovery (WHR) plant, which was installed by the Chinese company Sinoma. This helps to increase our efficiency and is a very good way to save fuel costs over a relatively short period of time."
"Over the three lines we have seven boilers and one turbine generator. It will be up and running in early 2013. It produces 18MW, which is about 25% of our total electrical needs. It is the biggest WHR system in Turkey. We are ahead in terms of WHR in Turkey and this installation may allow us to absorb future regulations more easily than our competitors."
"Elsewhere we use some alternative raw materials. We include alumina from local plants and we use phosphogypsum, which is a tricky, sticky material. We pay for the transport of the phosphogypsum but not the material itself as it is also a by-product from local works."
"In other parts of the plant we have three gas-fuelled power plants. They produce 160MW between them and are split between supplying the plant and sending power to the local grid."
GC: "How do the changing environmental regulations in Turkey affect your production process?"
HŞ: "Regulations are increasing very fast. Strict regulations came to Turkey about 10 years ago, which created some problems for the older plants. At Nuh Çimento, we have online analysers on all of our stacks that are directly monitored by the government real-time. We have analysis on HF, HCl and total carbon. We also have controls on NOx, SOx and dust."
GC: "Are there any problems with mercury?"
HŞ: "Not here. However, in the future the government will drop the limits for NOx from 1200mg/m3 to 400mg/m3 in an incremental process. We plan to install further systems for that so that we can drop our NOx output in line with these requirements by 2015."
Markets and the future
GC: "How much of the plant's production is for the domestic market and how much is exported?"
HŞ: "Around 3.8Mt/yr of cement was sold to the local market in 2011 and perhaps 1Mt/yr went to export from the port, which was a combination of cement and clinker. Material for the local market is distributed with trucks. That goes to all over the local area, mainly to Istanbul and Izmit. In any given month around two thirds might go to Istanbul, but it is dependent on construction there and in other cities."
"As well as local projects there will be a bridge constructed over the narrowest point of the Marmara Sea, at a point close to Gebze. It will save a lot of driving time as the Marmara Sea is only 3km wide there. The project was announced in July 2011 but the authorities are deciding on the exact location. I think they will finish it by 2015 or 2016."
"That project itself will demand a lot of concrete, which will mean a lot of cement has to be supplied but, once built, the bridge will make it easier to move our cement to different markets. However, it might also help some others enter our market more easily."
"Only the export material goes through the port. The export goes to countries like Russia, Georgia, France, Belgium, Italy, Romania and even Brazil."
GC: "What sets of circumstances allowed you to export to Brazil and Italy? Our perception is that the Brazilian market has strong domestic supply and that Italy has overcapacity at present."
HŞ: "In 2011 we supplied clinker to Brazil for a special project that was being constructed. The client was looking for good clinker and our clinker is really good. With reference to Italy, it may have plants that have closed, but that is in part because they can get it cheaper from places like Nuh Çimento."
"As well as these, we also export to southern Russia at the moment ahead of the 2014 Winter Olympic Games in Sochi, which is on the Black Sea and so is easily reached from here. There is a lot of construction currently going on there and Russian plants are not always the closest ones to Russian projects."
GC: "Turning to the local market, how seasonal is the cement market in the Istanbul region?"
HŞ: "We sell most cement between April and the end of October. During that period we would sell around 300,000t/month to 350,000t/month but in winter it would be around 100,000t/month to 150,000t/month."
"At the end of 2012 we continued to sell well into November due to unusually warm weather, which was good news for us. In the previous season we saw good sales continue all the way until January 2012. In December 2011 we sold cement like it was summer."
GC: "Nuh Çimento's quarry is very close by. As it is used up, there is more and more space. Is line four a possibility in the future?"
HŞ: "Yes, line four is a possibility in the future. Indeed line three was built where the quarry used to be in an area that was made flat by removal of raw material. If line four happens it would be a kiln similar to kiln three and we would increase from around 13,000t/day to around 20,000t/day (~6.4Mt/yr). Such a line would primarily be for export purposes because we have the good combination of quality and price that is desired."
"If it is built, we could then look at putting one of the older lines, which are less efficient than the new lines, on to a part-time schedule. In the local market we have to compete on price. The cement is almost the same, wherever you make it. If we can make it cheaper with more modern production lines, we can become everybody's favourite."
GC: "How long do you think that the current quarry reserves could last?"
HŞ: "I can see the quarry serving at least 60-70 years more but perhaps it could last as long as 100 years. It depends, obviously, on the rate at which we produce cement in the future. The quarry's reserves certainly do not impinge on our decision on whether or not to construct a fourth line."
GC: "What is your prediction for the Turkish cement market in 20 year's time?"
HŞ: "When I was a young engineer in 1980s, capacity was around 25Mt/yr of cement. When people would install a new line, critics would shout out, "What are you going to do with all this capacity?" or something like that. 30 years later we have hit 65Mt/yr production and we still need all of it. In 10 years it could easily hit 90Mt/yr production, a level that is widely predicted."
"The Ministry of Environment and Urban Planning took the decision at the end of 2012 for the wholesale removal of older buildings in many Turkish cities. In six years they will bring down around five to six million apartments and build new ones. Many are in earthquake zones and we need to build stronger buildings in those areas and elsewhere. This is clearly good news for cement plants, especially in this area close to Istanbul."
"In addition to this major ongoing project, there are plans for the new Bosphorus Bridge III and for a tunnel underneath it in the next five years. New roads are always coming and I see no reason to slow down cement production at Nuh Çimento in the next 30 years."
GC: "Thank you for your time."