Qatari Trade Promotion Services Suppliers and Manufacturers

Fly ash is a finely divided residue made from the combustion of pulverized coal that can be used to increase concrete durability and workability, while reducing permeability. As fly ash contains aluminous and siliceous components, it may form cement when mixed with water if the calcium content of the fly ash is high enough. Similarly, mixing fly ash with lime and water can create a substance similar to Portland cement. Fly ash can be separated into two main types, known as: Class F Class F fly ash contains particles covered in a type of melted glass allowing it to reduce the risk of concrete expansion and increase resistance to sulfates and alkali-aggregate reactions. Class C Class C fly ash contains a higher percentage of calcium oxide, making it more effective in strengthening structural concrete. Applications & Benefits of Fly Ash: Fly ash is used in commercial and industrial sectors for improving the durability and workability of concrete mixes. Fly ash is also used as filler in paints, adhesives, and metal and plastic composites. It's commonly used as structural fill for road construction and fly ash can be used to make bricks, ceramic tiles, plaster, Portland cement, and ready-mix cement.

Microsilica (silica fume) is a by-product of silicon metal or ferrosilicon industries, is an amorphous silicon dioxide SiO2. This product reacts chemically with the calcium hydroxide in the cement paste which yields a calcium silicate hydrate gel that significantly enhances strength and durability. The super fine microsilica fills the voids between cement particles creating a very dense, less permeable concrete. Physical characteristics: Color: gray or gray white powder Bulk density: 320-700 kg/m3 Chemical composition: Items SiO2 Al2O3 Fe2O3 MgO CaO Na2O Moisture Content 75-98% 1.0-0.2% 0.9-0.3% 0.7-0.1% 0.3-0.1% 1.3-0.2% Fineness: the fineness of the silica fume is less than 1 1/4m, and the average particle size is 0.1 0.3 1/4m, and the specific surface area is 20 - 28 m2/g. The fineness and specific surface area are about 80-100 times of cement and 50-70 times of fly ash. Maxtech Micro Silica supplies will be as per QCS 2014 (ASTM C1240): SiO2: >/= 92% LOI:

GGBFS Ground granulated blast furnace slag (GGBFS) The ground granulated blast furnace slag (GGBFS) is a by-product of iron manufacturing which when added to concrete improves its properties such as workability, strength and durability. This material is obtained by the heating of iron ore, limestone and coke at a temperature about 1500 degree Celsius. The process is carried out in a blast furnace. The formation of GGBFS is not direct. The by-product of iron manufacturing is a molten slag and molten iron. The molten slag consists of alumina and silica, also with the certain amount of oxides. This slag is later granulated by cooling it. For this, it is allowed to pass through a high-pressure water jet. This result in quenching of the particles which results in granules of size lesser than 5mm in diameter. The main constituents of blast furnace slag are CaO, SiO2, Al2O3 and MgO. These are the minerals that are found in most of the cementitious substances. The particles are further dried and ground in a rotating ball mill to form a fine powder, known as ground granulated blast furnace slag cement. Now different methods can be employed to perform the main process called as the quenching. Applications & Benefits of GGBFS: In concrete: The incorporation of ground granulated blast furnace slag in concrete manufacture gains many advantages which are mentioned below: GGBFS in concrete increases the strength and durability of the concrete structure. It reduces voids in concrete hence reducing permeability GGBFS gives a workable mix. It possesses good pumpable and compaction characteristics The structure made of GGBFS constituents help in increasing sulphate attack resistance. The penetration of chloride can be decreased. The heat of hydration is less compared to conventional mix hydration. The alkali-silica reaction is resisted highly. These make the concrete more chemically stable. Gives good surface finish and improves aesthetics. The color is more even and light. Lower chances of efflorescence. The maintenance and repair cost of structures are reduced thus increasing the life cycle of concrete structures. Unlike cement, GGBFS does not produce carbon dioxide, sulphur dioxide or nitrogen oxides. White Cement: White Portland Cement is of high quality, whiteness and strength, it essentially has the same properties and characteristics as gray cement, except for color. It is widely used in numerous applications such as precast concrete, cast-in-place concrete, terrazzo, median barriers, curbs, tile grout, paint, masonry units, swimming pools, glass fibre reinforced surface bonding mortars.

Microsilica (silica fume) is a by-product from silicon metal or ferrosilicon industries, is an amorphous silicon dioxide SiO2. This product reacts chemically with the calcium hydroxide in the cement paste which yields a calcium silicate hydrate gel that significantly enhances strength and durability. The super fine microsilica fills the voids between cement particles creating a very dense, less permeable concrete. White Cement advantages: Sustainability: Solar Reflectance Index (SRI): Floors finished with white or pastel color concrete will have a much higher SRI than floors with gray concrete, therefore they will reflect light better, and generate energy savings for the lifetime of the floors. Reduction of Heat Island effect: By constructing buildings with white concrete roofs or light-colored roof tiles, the Heat Island Effect is reduced from surfaces generating less heat and improved reflectivity. Architectural Concrete: White Portland Cement is ideal for decorative concrete and Architectural Concrete applications, Masonry and Cementitious Building Products. A key advantage of using white cement for these applications is that it provides a base color that can be tinted to custom colors to meet any color spectrum demand.