Cementir's Glocal Practice in white cement

Abdel Hamid Gadou, Sinai White Portland Cement
Alexey Igorevich Tomashevskiy, Aalborg Portland Russia
Michele Di Marino, Jesper Sand Damtoft, Erik Pram Nielsen, Bi Zhuo Qin, Cementir Group
Alexey Evgenievich Marusov, GC ArkhiKamen

ALITinform - International Analytical Review - No.1(54) - Dec. 2019

White Portland Cement plays a leading and unique role as an essential binder ingredient of high-quality mortars and concretes. Compared with grey Portland cement, higher degrees of chemical purity and the inherent stability in terms of quality due to a very selective use of raw ingredients to ensure constant colour performance, results in, among others, enhanced interaction with admixtures and a predictable and reliable performance. Given that whiteness is a key performance parameter for White cement, only raw materials with very low iron content are used in the manufacturing process of White cement. The formation of very slow reacting iron-containing clinker minerals is thereby also avoided, resulting in a much denser structure of the hydrated White cement, directly translating into higher strength and lower porosity of the concrete manufactured with White cement.

White cement is used for many applications where the whiteness is the main parameter of interest, such as dry-mix products, tiles, artificial stones, precast concrete elements, terrazzo concrete, etc. Further properties of Aalborg White® cements are engineered for facilitating efficient manufacturing processes at customers, and the enhanced performance of their products. Furthermore, it is regarded as a high end and value-adding product, and its use varies from application with aesthetic requirements to structural ones, for both renovation (decoration, repairs & maintenance work) and new build.

Aalborg White® cement gives further value-adding contributions to the society in terms of sustainability and safety improvement. Light or white coloured surfaces reflect the sunlight more efficiently than dark ones. White concrete median barrier’s reflectivity is almost 50 % higher than grey in wet weather. Furthermore, at night, white concrete median barriers enhances visibility compared to the grey concrete, which greatly improves the driving safety in the highway.

Leading White cement Producer in the World

Cementir Group is the world’s leading producer and exporter of White cement, with production facilities located on four continents and a production capacity of over 3 million tons in a global market share of 16 %. The Group markets its White cements in more than 70 countries worldwide under the global product brand Aalborg White®. Production plants are located in Denmark, Egypt, Malaysia, China and the United States.

Innovation and  “global  localization  (Glocal)”, are the two main strategic objectives of Cementir Group White cement business, breaking out of the traditional paradigm in cement industry development, and strategically positioning the sustainable path and trend of White cement business model with a long-term vision. “We want to unlock the full potential of working with customers by having a new strategic focus towards product and technology-based applications.  

By enhancing the visibility into the customer’s value chain, the Group aims at providing a differentiated and tailored value proposition which starts from theproduct  offering  at  such,  developing  into  value  added  services  to  co-development and  innovation  initiatives.  Cementir  values  this  mutual  and  close  relationships based  on  common  desire  to  find  the  most  sustainable,  cost-effective  solutions  to complex  challenges  and  mega-trends  in  construction  and  building  materials,”  Mr.Michele  Di  Marino,  Chief  Sales,  Marketing  &  Commercial Development Officer, states.

The Unique White cement Production Process

Chemical purity of raw material, raw mix grinding equipment and alternative fuel used in White cement manufacturing are essential factors affecting the whiteness of clinker. In  order to have chemical purities, high-grade raw materials are needed for white clinker production. Cheap and quarried raw materials are commonly used for grey clinker production, which usually contain substantial amounts of chromium, manganese and iron. For   example, limestone containing 0.3–1% Fe2O3 is typically used for grey cement production, whereas a maximum of 0.1% is used for White cement manufacture. Furthermore, conventional clay for grey cement raw mix containing typically 5–15% Fe2O3 is usually replaced with kaolin with Fe2O3 content below 0.5%. High-grade sand with low iron content is utilized to compensate for the low SiO2 in kaolin. Additionally, in the process of raw mix grinding, ceramic grinding equipment is often used to avoid the notable wear of chromium steel grinding equipment causing chromium contamination to the white clinker production. Equally important, alternative fuels like petcoke are used in Cementirs plant in Egypt to  replace e.g. coal that can typically be used for grey clinker production, in order to avoid iron  and other undesired elements in white clinker manufacturing.

Quenching of red-hot clinker is a unique process of producing white clinker. It is necessary to cool the clinker temperature  out of  kiln  from  1200  °C  to  below  600  °C  in a few seconds by quenching with air or cold water, to that  would  occur  in  the  presence  of  oxygen,  affecting  negatively the whiteness of the clinker. In addition, this process favours the reduction of Cr (VI) to Cr (III) or Cr (II) and consequently leaves white clinker free of soluble Cr (VI), is common in grey clinker.White clinker has higher C3S and C2S  content  compared  to  grey  cement  —  C3S  content  in  white  clinker  is  usually  more  than  3  %  higher  than  grey  clinker. This indicates that the early and late strength of White cement is generally higher than that of grey cement due to the total content amount of composition C3S+C2S  in  white  clinker  is  at  least  6  %  higher  than  the equivalent composition in grey clinker. As a result, White  cement  has  higher  mechanical  performance  than grey cement.

Global Standardized Production Process and Quality Control System

Sinai   White   Cement   plant   (SWC)   was   incorporated  in  1999  and  is  located  in  the  Sinai  Peninsula of Egypt. It sold its first bag of White cement to  the  market  in  November  2001.  In  2004,  Cementir  Group  carried  out  the  strategic  layout  of  the  plant,  resulting  in  a  second  White  cement  production  line  starting production in October 2008. As planned, SWC became  the  largest  White  Cement  plant  in  the  world  with 1,100,000 MT annual production capacity of high-quality White cement by the end of 2009.

Thanks to the strategic geographic plant location close  to  the  different  sea  ports,  Sinai  plant  owns  vast  experiences on Aalborg White® cement export to Europe including  Russia,  Middle  East,  Africa  and  Americas,  as  well  as  offering  customer  services  spanning  from  commercial support, logistics and technical support. The technical talents with multinational experience in SWC plant ensure proper adherence to state of art production technology  &  emerging  trends,  offering  the  flexible  product solutions to satisfy the ongoing changing needs of customers together with Cementir’s global R&D centre in Aalborg, Denmark. 

SWC's own quarry has a very pure limestone with very  low  iron  content,  which  enables  the  production  of  White  cement  with  high  whiteness.  Unlike  grey  cement, White cement has a very complex production process  spanning  from  the  selection  of  raw  materials,  washing  and  homogenization  phase  to  the  clinker  production,  and  each  production  step  is  monitored  by  a  comprehensive  and  well-proven  quality  control  system  to  ensure  the  finished  products  with  high  whiteness and high strength. The advanced technology and computerized controlling are vital elements in the quality  control  system  in  accordance  with  EN  197  to  make the White cement with stable and superior quality and win the trust of worldwide customers.In addition to the routine testing of the finished products,  further  auto-control  and  advanced  testing  is  carried  out,  such  as  cement  particle  size  distributions  analysis, cement chemical analyses, laboratory furnaces set  up  for  small  scale  burning  of  cement  clinker  for  burnability  testing,  clinker  reactivity,  the  distribution  of  minor  components  and  their  impact  on  cement  performance  and  colour. Laboratory  grinding  of  the  clinker to test the cement performance is also performed prior to full-scale production trials. SWC plant as part of the Cementir Group global White  cement  production  footprint  is  an  integral  part  of  the  Group  Quality  system,  with  standard  processes  and  internal  best  practice  sharing  within  the  different  plants in the Group. This guarantees high and consistent quality standards and assures a continuous improvement approach in the operations.

Cementir’s Sustainability in White cement Industry

Cementir  regards  sustainable  growth  as  both  a  responsibility and a requirement for continuing to work in the cement industry. Four pillars of sustainable concept are  identified  for  the  Group,  comprising  production  recycling,  innovative  product  technological  solutions,  talent  attraction  and  motivated  working  environment,  as well as community caring. In  Cementir’s  Sinai  plant,  all  production  equipment, including two kilns, meet the international environmental  and  safety  standards,  and  comply  to  the European energy and environmental requirements. Petcoke  has  been  used  for  thermal  energy  production  since  2016.  An  environmental  reporting  system  and  online  environmental  monitoring  system  were  implemented  with  SWC  participation,  allowing  the  central  authorities  to  supervise  plant  operation  and  control the emissions.SWC plant has always been respecting and taking care  of  the  local  community  and  residents  through  offering  job  opportunities  and  being  supportive  of  local  economy  development,  residents  living  quality  improvement,  village  security  and  local  education  facilities  &  funding  by  means  of  various  social  responsibility activities as a practice of the sustainable development concept of Cementir Group.

White cement Market Overview in Russia

In  the  Russian  market,  more  than  50  %  of  the  White  cement  is  applied  to  dry  mix  mortars  with  decorative purpose, and about 40 % for precast concrete applications, both for wet casting and semi-dry casting products. Russia has a sophisticated experience on glass fibre reinforced concrete (GFRC) based on White cement and is regarded as one of the leading countries in the use of GFRC elements as a lightweight concrete material for façade  decoration.  Ultra  High-Performance  Concrete  (UHPC),  as  an  emerging  and  robust  building  material,  is  becoming  increasingly  popular  in  Russia  serving  as  an  ideal  material  for  very  slim  decorative  panels  and  building  structure  elements  in  the  field  of  commercial  &  residential  building,  landscaping,  infrastructure  and  even military purpose.

Due to the aggressive climate conditions in Russia during winter, a superior concrete freeze/thaw resistant property  is  a  must  for  external  building  materials.  Concrete  based  on  Aalborg  White  cement  represents  such an ideal robust and durable building material to be used in such an aggressive environment.

Following  the  growing  trend  towards  higher  architectural  aesthetic  requirements  and  sustainable  green  building  development,  White  cement  demand  is  estimated  to  grow  by  2–3  times  in  the  next  10  years  in  the Russian market, mainly applied in the prefabricated façade  systems.  Lightweight,  high-strength,  easy-to-transport  prefabricated  panels  will  be  widely  favoured  by the market.

White cement footprint in Russia

GC  ArkhiKamen  is  one  of  the  pioneering  manufacturers in Russia to use Aalborg White® cement for the manufacture of architectural facade elements in 1996,  when  the  technology  of  vibration  compression  of  semi-dry  cement–sand  mixture  (better  known  abroad  as Cast Stone) first came to Russia. The key factors that influenced the popularity of Cast Stone products in Russia was  a  successful  combination  of  impressive  technical  and aesthetic characteristics of the finished product. The texture of the architectural elements of Cast Stone exactly repeats the texture of natural Sandstone, while having a high degree of uniformity.

Based on Aalborg White® cement, GC ArkhiKamen has developed a series of precast concrete elements like GFRC  (Glass  Fibre  Reinforced  Concrete)  and  some  wet  casting  concrete  components.  These  facade  decorative  elements  with  high  architectural  aesthetics  are  widely  favoured  by  architects  and  applied  in  many  iconic  buildings.

“To ensure high performance of concrete products in the aggressive weather conditions in Central Russia, with multiple transitions through 0 °C and high humidity, we tested many product samples from different White cement manufacturers and conducted long-term climatic tests of samples on their production base. As shown by many years of practices, Aalborg White® cement most accurately meets our requirements to the binder in terms of high whiteness, high  strength  and  excellent  machinability.  In  addition,  the  stability  of  these  indicators  in  the  supply,  stretched  over time, is of fundamental importance for us. Supplying façade  products  to  a  project  often  stretches  over  several  years, and the products delivered at any time are required to be the consistent in terms of visual indicators. The use of high-quality Aalborg White® cement significantly reduces the risks of product rejection and ensures an optimal cost performance,.“  Alexey  Evgenievich  Marusov,  General  Director of GC ArkhiKamen, explained Alexey continued: “High quality GFRC is a trend of  increasing  demand  for  the  original  decoration  of  facades with technological, fireproof and visibly expressive materials that allow to form a unique image of the building in a variety of stylistic techniques – from classicism to high-tech. ArchiCore® GFRC precast elements developed based on Aalborg White® cement possess the distinguished high strength, water-resistance, minimal shrinkage deformation after demoulding and the absence of fracture. Large-Format panels  of  GFRC  carrying  metal  frame  have  long  been  successfully  used  for  facades  in  the  United  States,  Japan,  European countries. In recent years, these technologies are of increasing interest in Russia.”

Cast Stone Application in the Ritz-Carlton Hotel in Moscow, Russia

The  Ritz-Carlton  hotel,  one  of  the  best  deluxe  hotels  and  the  first  Ritz-Carlton  chain  hotel  in  Eastern  Europe,  was  built  on  the  site  of  the  former  Intourist  Hotel. As a super 5 stars Hotel, the building of the new hotel organically fits into the historical environment of the centre.

The classical style of the precast ArchiStone® cast stone elements based on Aalborg White® cement on the first  six  floors  completed  the  strong  and  solid  image  of  the  building.  The  highly  refined  decorative  concrete  elements,  coffered  ceiling  balconies,  rusticated  corners  look amazing on the exterior of this international luxury hotel — The Ritz-Carlton.

GFRC Façade Application in Administrative Building in Moscow, Russia

The  architectural  design  of  this  building  was  made  by  a  team  of  the  5th  architectural  workshop  of  the  JSC  "Mosproject-2  n.a.  M.  V.  Posokhin"  under  the  leadership  of  Mikhail  Leonov  &  Chief-architect  Boris  Pashchenko. The gable extended more than 3 meters and is  supported  by  the  metal  carrier  system.  The  exterior  ArchiCore®  GFRC  facade  elements  based  on  Aalborg  White® cement presenting the modernism of the building were  manufactured  for  this  special  Administrative  Building in Michurinsky Avenue.