With the ever-increasing emphasis on ecology, cost effectiveness and quality workmanship, the building trade has had to review how it does things. In recent times the building trade has gone through many changes with regards to materials and practices used.
There is no doubt that the building trade has now become more environmentally aware in recent years. After all, we only have one planet and we need to look after it – not abuse it. It is good to see that many are reviewing which materials they use in order to be more green or environmentally friendly. This can be good news for those who want a top quality material at a low price.
Cement clinker is a by-product of the cement manufacturing process and is recycled into a low cost building material called cement kiln dust or CKD. A lot of this material is sold off cheaply as it doesn’t have much use – however, there are many people out there making use of this versatile material and getting some great results!
In recent times the building trade has gone through many changes with regards to materials and practices used.
Over the years a number of new products have come on to the market and in particular one material: Portland cement.
Portland cement, as we know it today, was invented in 1824 by Joseph Aspdin, who named it after stone quarried on the Isle of Portland, Dorset. This strong cement was produced by burning finely ground chalk with finely divided clay in a kiln at a temperature of about 1400 C – 1500 C.
The clinker is then cooled and ground to a fine powder with a small addition of gypsum (used to control setting properties) in order to produce Ordinary Portland Cement (O.P.C.). O. P. C is the basis for most concrete mixtures.
In recent times the building trade has gone through many changes with regards to materials and practices used. The cement industry is no different, new technologies have been introduced and many old practices have been altered or replaced.
One of these new products is Cempacks, a mixture of clinker and aggregate that can be used as a building material in its own right or blended with ordinary Portland cement to produce a high quality concrete.
Cempacks is produced by a process known as heat curing, where water is added to the raw materials at ambient temperature. The wet mix is then heated rapidly in a kiln (to temperatures in excess of 1500 degrees Celsius) to a semi-liquid state. This process enables chemical reactions to take place between the raw materials and the water to form new compounds including C3S (tricalcium silicate), C2S (dicalcium silicate), C3A (tricalcium aluminate) and C4AF (tetracalcium aluminoferrite). The end result of this process is a material called clinker, which essentially consists of interlocking crystals of the four main compounds listed above.
When clinker is ground it produces Portland cement, which when mixed with sand, aggregate and water forms concrete
In recent times the building trade has gone through many changes with regards to materials and practices used. Clinkers are formed by the heat processing of cement elements in a kiln. Limestone, clay, bauxite, and iron ore sand in specific proportions are heated in a rotating kiln at 2,770 Fahrenheit (1,400 Celsius) until they begin to form a clinker, which are round balls ranging from 0.2 inches to 2.0 inches (5-50 mm) across. The type of kiln now used is the rotary kiln, accounting for 90 percent of all cement clinker production worldwide (Hahn, et al.).
The most common use for Portland cement is in the production of concrete. Concrete is a composite material consisting of aggregate (gravel and sand), cement, and water. As a construction material, concrete can be cast in almost any shape desired, and once hardened, can become a structural (load bearing) element. Portland cement may be grey or white. Portland cement blends are often available as inter-ground mixtures from cement producers, but similar formulations are often also mixed from the ground components at the concrete mixing plant.
Portland cement blends are often available as inter-ground mixtures from cement producers,
Over the years there has been many new products and processes put in place to help with building, these have included such materials as PVA glue, plasterboard and lightweight aggregate blocks.
But of course not all new products are a success and many have disappeared into history never to be heard of again.
For example, have you heard of cement clinker? I thought not! But what is it? It is a type of granulated blast furnace slag which are dried and ground down into a fine power.
It was used for all sorts of things including making cements and other building materials such as concrete. Cement clinker was first produced in the United Kingdom in the early 19th Century.
Its production is currently around 30 million tonnes per year, with more than half produced in China.
In fact, the world’s largest exporter of cement clinkers is Germany. And where do you think it gets its supply from? Why, the Ruhr Area of course! The Ruhr Area is famous for its production; it produces around 58 percent of its total output.
Cement clinker is a semi-finished good, which needs to be ground in a mill before it can be used together with other materials to make concrete. As a result of changes in prices of the raw materials and energy as well as further development of the cement market, there is presently a trend towards the increased use of alternative fuels, raw materials and additives in cement production.
Cement clinker is a semi-manufactured material. It results from the controlled heating of a specific raw material combination of calcium, silica, alumina and iron in exact proportions. This combination includes at least 4% calcium oxide (CaO) and up to 6% iron oxide (Fe2O3). However, the main components are CaO, SiO2 and Al2O3. The raw materials are ground to a fine powder and then it is burned to form cement clinker. The cement clinker produced is finely ground to produce Portland cement.
Cement Clinker Market: Drivers and Challenges
Due to the ongoing urbanization trend and infrastructure developments, the demand for cement has increased significantly across the globe. Cement is a key ingredient in concrete, which is used extensively in construction activities such as highways and bridges, residential buildings, industrial structures and other infrastructure facilities.