This is a powdery substance that non-professionals incorrectly call concrete. The mistake that is made is quite massive, in fact, the concrete itself is composed of cement, sand, gravel (or some other admixture), and water, after hardening of this mixture, which is pre-mixed until homogenized, the so-called concrete is obtained. It is used for masonry, pouring molds into the formwork, and more. бетонови тротоарни плочки
The cement substance itself is obtained by very fine grinding of a substance called cement clinker and gypsum. The grinding itself is done in special ball mills. All concrete mixtures and concrete pavements for the yard are created from cement and inert materials.
Cement was discovered by Joseph Aspdin and belongs to the group of so-called hydraulic binders, which means that when you mix them with water they form a mixture that resembles a paste. This paste has the property of being Cement Milk (cement and water) plastic and hardening.
As it hardens, it changes its strength properties and acquires greater strength. Cement is usually made of limestone and clay, but quite often various additives such as marls and shale are added.
The biggest costs in the production of concrete are made during its firing and grinding.
Because these events burn a very large amount of energy resources. Coal is most commonly used, but the effects of its flue gases are detrimental to the environment. Another source of energy is natural gas, which, like coal, pollutes the environment. There are many factories in Bulgaria for the production of our much-needed cement.
The largest of them are Plama, Pleven, Vulkan, Dimitrovgrad and Devnya Cement. Devnya Cement is the only enterprise in Bulgaria that produces cement by wet method. This method is much more environmentally friendly than the dry one, because it avoids the dusting of the finest fraction of concrete mills, which even the best filters cannot stop.
But the reason why the wet method is not applied by all factories for cement production in Bulgaria is that this method is significantly more expensive, requires more energy, and hence increases the price of the final product – cement.
The areas around the factories that produce cement are usually quite polluted, in Dimitrovgrad, for example around the Vulkan plant, the roofs of the houses are gray.
This is due to the dust that is released into the atmosphere and due to atmospheric precipitation it falls on the roofs and hardens. This does not have much effect on roofs, but for residents who constantly inhale this substance pSiment in paper bags is quite serious.
Nowadays, cement is a very necessary and constantly used substance. It is mostly used for the preparation of concrete. In horticultural practice, concrete is often used to build a garden stone path and various types of grass joints. The strength of concrete depends very much on the brand of cement used for their production.
But we really need to think about how to make our plants more efficient from an economic point of view, but let’s not forget the most important thing, namely that they are environmentally friendly, especially if they are quality cement paving slabs.
http://www.epfl.ch/
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http://www.open.ac.uk/
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http://www.maastrichtuniversity.nl/
http://www.colorado.edu/