Büyükçekmece: Turkey’s alternative fuel pioneer

The Büyükçekmece cement plant is located at the southern end of the Büyükçekmece lake on the Marmara Sea, 50km to the west of Istanbul, Turkey. The 5900t/day facility dates back to 1967 and is operated by Akçansa, which itself is owned by Germany's HeidelbergCement and the Turkish Sabançi Group. Global Cement Magazine recently visited the plant and spoke to Okay Kilinç, the Büyükçekmece plant manager. The interview covers his background in the cement industry, the history, current production process and alternative fuel regime of the plant and how he sees the Turkish market developing in the future.

Global Cement: "Thank you for allowing our visit to the plant today. Can you describe your background in the cement industry?"

Okay Kilinç: "Thank you. I started at the Büyükçekmece cement plant as a production engineer in 2002. In 2004 I went to Germany as a trainee engineer in various plants as part of the HeidelbergCement training programme."

"After six months I came back to Turkey and the Büyükçekmece plant and within a year I was promoted to production supervisor. Four months later the production supervisor at our Çanakkale plant resigned and I was offered the position there, which I accepted."

"At the same time Çanakkale's second line project was underway, so I oversaw the conclusion of that successful project. After one year I came back to Büyükçekmece as a production manager in September 2009. Four months later I was promoted to the position of plant manager at Büyükçekmece."

Raw material

GC: "The plant is positioned at the south end of the Büyükçekmece lake. The quarry is at the north end of the lake. Presumably you are able to float the raw material down from the quarry by barge?"

OK: "This would be the best solution but unfortunately it is not possible. We need to carry the material 17km by truck on public roads because the Büyükçekmece lake is a source of drinking water for Istanbul. This means that we are not allowed to transport material on the lake."

"The decision to turn Büyükçekmece into a reservoir was not good for operations. Our quarry used to be closer to the plant but we were kicked off to another location that, unfortunately, was further away."

GC: "Would you say that the plant's current location is compromised by the need to transport raw material by truck?"

OK: "Transporting the raw material by truck is costly, time-consuming and it is far from ideal from an environmental perspective. However, we will maintain our current position because it is not economical to consider moving the plant in the foreseeable future. We have a dominant position in the local market on the European side of Turkey and Greater Istanbul and that is very valuable to Akçansa."

Production process

Once the limestone arrives at the cement plant site it is crushed using a 600t/hr Hazemag impact-type crusher. Gypsum, pozzolan and iron ore are crushed using a KHD hammer-type crusher and some limestone is also crushed in an identical machine. Schist is crushed using an FLSmidth 300t/hr hammer crusher.

The plant has a 38,000t storage dome, from which premix material is fed to three raw mills. Line 1 has a 90t/hr KHD ball mill. Line 2 has a Gebr. Pfeiffer MPS4500 vertical roller mill and there is a 115t/hr FLSmith ball mill for Line 3. Also there is another Gebr. Pfeiffer MPS 2900 vertical roller mill, which is used for additive material. Following preparation the meal makes its way to the three kilns (see table below).

Table 1: Kilns at Büyükçekmece

OK: "In 1967 the first kiln, a 1300t/day KHD line, was commissioned. In 1969 it was joined by an identical line, although this has since been upgraded. The third line was commissioned in 1974. It is an FLSmidth satellite-cooler design that produces 1700t/day and is the only satellite-cooler kiln in Turkey. It's rare, so we will have to charge you for a ticket to see that!"

GC: "How was line two altered?"

OK: "Originally lines one and two were identical but in 1989 we made a series of changes to the line. After some experimentation we settled on a solution from VoestAlpine Austria, which created a separate line calciner, allowing the kiln to reach up to 2800t/day. Today our total capacity is roughly 5900t/day."

"Recently, in 2012 we upgraded line three with the installation of a new baghouse by the Italian company Boldrocchi SpA. This improved our dust emissions and Boldrocchi will install another baghouse on line one later in 2013."

Alternative fuels

GC: "Can you describe the use of alternative fuels at the Büyükçekmece cement plant?"

OK: "Of course. We are the pioneer of alternative fuel use for cement in Turkey. We have the licence number 0001! We started burning alternative fuels in 2005, starting with whole tyres, as a result of our link to HeidelbergCement. HeidelbergCement has a vast experience of alternative fuel use around the world. It has used them for around 20 years."

"However, the early days here with alternative fuels were very interesting for us and probably for your readers, because only after we self-built a whole-tyre feeding system in-house, did we start to look for tyres in the market. In Turkey we had five million vehicles and yet we could not find one used tyre for sale!"

"In the end we actually started negotiations with the local Bridgestone producer and we bought second-quality new tyres from them at double the price of the petcoke that we had been seeking to substitute! This sounds very stupid but we needed to test the system and the kiln's reaction so that we could prove that the concept would work in Turkey with used tyres. It wasn't funny at the time but it's funny to me now!"

GC: "What is the situation now?"

OK: "In 2012 we reached around 15% alternative fuels in the plant and we consumed 12,000t/yr of tyres. In addition we have started to burn industrial plastic, which is similar to RDF but from industrial sources. We installed a 5t/hr plastic shredder from Vecoplan for this purpose in 2008."

"Mid-way through 2010 we started to use dried sewage sludge, which comes from a biological-treatment plant around 25km away. We had another sewage sludge source start at Ambarli, 17km away, at the start of 2013."

"Recently we found a source of RDF from the company Recydia. They have a new waste-recycling plant on the Anatolian side close to the town of Sile. The plant is very new. RDF use is an emerging market in Turkey but during 2013 with the help of Recydia, (as well as more sewage sludge, tyres and plastic) we aim to reach an alternative fuel substitution rate of 25%. In January 2013 it was around 23%."

"In conclusion we have had a steep learning curve but we still have a leading position in alternative fuel use in Turkey. We have made a good investment here."

GC: "Which kilns run which fuels?"

OK: "All three kilns run alternative fuels. Kilns one and two run all of the different types of alternative fuels and kiln three runs everything except RDF and industrial plastics. In the future the additional volume of RDF will be fed to kiln three as well as one and two. We are adding a new feeding point for this to the kiln two calciner. We are modifying the current system and investing in a Euro3m transport system from a Vecoplan-licensed Turkish contractor."

"RDF is very difficult to transport because it is very fluffy and light. Vecoplan's 'VecoBelt' closed conveying system has an air cushion under the belt. This means that you reduce friction and

mechanical resistance, require fewer rollers and thus cut down on maintenance costs. It is a very good solution for moving this tricky material. Only a few cement plants in the world currently have this type of installation so we are at the forefront in this regard."

GC: "What is the plant's alternative fuel target?"

OK: "For the next step, we want to reach up to 40% alternative fuels, because after 40%, under Turkish regulations, we head into a different classification of facility. After 40% you legally count as an 'incinerator' and that would require a change in our licence, even though our primary industrial goal is the production of cement. So the first step is to reach 40% in the next five or so years."

Table 2: Proportions of different fuels used at Büyükçekmece in January 2013

Back to the process

After the clinker has been produced and cooled it reaches two clinker storage facilities, one of 55,000t and one of 35,000t. From there it is processed in one of the plant's four FLSmidth cement mills, which run at 50-100t/hr. These are summarised in the table overleaf.

Post grinding the material goes to the plant's packaging and distribution facilities, of which there are five. Two are from when the plant was first built and three subsequent additions have come courtesy of international and local players. They are summarised in the lower table.

Table 3: The Akçansa Büyükçekmece cement plant has four cement mills, all of which were supplied by Denmark's FLSmidth.

Distribution, markets and the future

GC: "What is the production regime at the plant at the moment?"

OK: "At the moment we are operating at maximum capacity on all three kilns 24/7. There is high demand."

GC: "Can you summarise the products made, distribution methods used and the markets targeted by the plant?"

OK: "In terms of products, 85% of our production is OPC. At the moment it is also around 85% bulk sales due to the amount of concrete that is made by our customers. We actually have some of the packing systems idle at the moment because our customers want bulk in preference to bagged cement."

"In terms of markets, Büyükçekmece does not export cement. We only supply the local market and that is by truck only. In terms of local destinations, around 80% heads east to the Istanbul/Marmara region and 20% heads towards towns closer to our EU borders."

"Akçansa exports cement to other countries from Çanakkale because we have our own jetty there. It's easier and cheaper to export from there because it was designed that way."

Table 4: The Akçansa Büyükçekmece cement plant has five packing and distribution units from a number of local and international suppliers.

GC: "Istanbul is growing very rapidly and demanding a lot of cement. Can you see any change to that situation in the foreseeable future?"

OK: "I don't think there will be a change in the situation. Turkish people like to build and expand and Istanbul's growth shows no signs of slowing down. We have a lot of serial landlords that rent properties to many people, especially young people, which we have a lot of in Turkey. The population is also very mobile and the desire to come to Istanbul is always very strong. So from a population standpoint we see no slowing of demand for construction."

"We also have numerous projects in central Istanbul to replace old buildings that were damaged by earthquakes in the late 1990s and early 2000s. With all of that in mind I don't foresee a need to sell Büyükçekmece's cement to the export market at the moment. Perhaps from Çanakkale we will be able to send more cement to our export markets, but that remains to be seen."

GC: "Thank you for your time."