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SBS 2511 GAGRINDING AID
WE ACCEPT THE CHALLENGE
The cement industry is going through a period of change and the
challenges that cement producers face – reduction of energy
consumption and decrease of clinker factor – are becoming ever more
important. In addition, buoyant market growth is compelling production
facilities to increase their efficiency, pushing plant performance to the
technical limits. Within the Kyoto Protocol, cement producers are
committed to an active reduction of CO2 emissions. However, the
enhanced integration of Supplementary Cementitious Materials (SCM’s)
like slag, fly ash, pozzolan or limestone, has implications for product
quality and performance.
WE ACCEPT THE CHALLENGE
On the other hand, every supplier wants to deliver higher performance in
order to speed up the construction process by still guaranteeing
durability, flexibility and a high level of aesthetics. Building upon our
recognized leadership in the field of concrete technology, FAIRMATE
has accepted the challenge and is committed to supporting cement
producers in meeting their objectives, by delivering added value with
new cement additives. We help our customers to be more successful.
BENEFITS
Reduces grinding costs : The increased mill output with SBS 2511 GA
at same cement fineness and energy consumption provides savings
through lower grinding costs per ton of cement. Increases compressive strength and flexural strength of cement :
Increases as high as 25% are not uncommon however the average of
all tests for all ages is 10%. Increases the flowability of cement : The dry dispersive action of
SBS 2511 GA improves the cement flowability characteristics. Improves the efficiency of the grinding process. Increases the bulk density by upto 5%. Improved cement dry flowability. Reduced cement mill grinding temperature which helps in maintaining
the quality of cements.
USES
SBS 2511 GA is used as a grinding aid for Portland and other
hydraulic cements. The special characteristics of SBS 2511 GA
allows it to be effectively used in the cement plants that constantly
have problems with hard and hot clinkers.
DESCRIPTION
SBS 2511 GA is an aqueous solution of an amine acetate salt and is an effective
dispersant particularly developed for use as a grinding aid for Portland cement and
other hydraulic cements. SBS 2511 GA conforms to ASTM C 465. It helps in
improving the efficiency of the grinding process by reducing the surface energy
forces that causes agglomeration of the newly fractured cement particles. It is
effective in both open circuit and closed circuit cement mills. The improved
flowability of cements with SBS 2511 GA results in faster loading and unloading
times of bulk tankers. Also, it helps in increasing the bulk density of cement and
helps in providing increased storage capacities of silos and bulk tankers. However, it
is recommended to dilute with 5 parts of water or more to ensure greater
proportioning accuracy and better additive distribution. SBS 2511 GA helps in
increasing the mill output at same cement fineness. SBS 2511 GA is compatible
with all types of cement.
PROPERTIES
Specific Gravity : 1.100 - 1.120
pH : 8 - 10
Viscosity : Maximum 30 seconds using B4 cup
@ 30ºC
Foaming Tendency : None
Insolubles : 0.1 % max
DISPENSING
SBS 2511 GA can be added at the clinker feed conveyer belt or
directly into the cement mill's first compartment. A proper dosing
pump is required to ensure the correct dosage into the cement for
obtaining the optimum performance. Our technical supports are
available to provide assistance in the use of SBS 2511 GA with the
manual, automatic or computerized dispensing system.
Mechanisms during grinding in the cement mill :
The mechanisms in charge when improving the grindability of a clinker must be
explained from a physico-chemical point of view. In general, the surfaces of the
clinker particles are not in thermodynamic equilibrium due to the incomplete surface
bonds, which lead to a free surface charge. As in all systems, the paricles will try to
approach equilibrium by lowering the free energy. Which in turn is done by
aggregation and adhesion to surfaces. When the clinker is entering the cement mill
the particles are coarse and the energy considerations are not significant. As the
clinker is size reduced during grinding, the free energy of the surface increases and
the non equilibrium become significant. The aggregation and agglomeration will
therefore become increasingly significant and the efficiency of the mill is reduced.
This is shown in Figure 1b.
PRINCIPLE MECHANISMS AND DESIRABLE EFFECTS OF QUALITY IMPROVERS
By using grinding aids the organic additives are adsorbed to the surface of
the clinker/cement particles. This reduces the energy needed to break
down the particles and reduces the surface charge. The latter is thus
preventing the cohesion of cement particles. The organic additives also
change the electrostatic forces between the cement particles by reducing
the attraction forces (Van der waal) and increasing the repulsion forces.
The effect of using a grinding aid is shown in Figure 1a. the additives are
thus behaving as surfactants.
PRINCIPLE MECHANISMS AND DESIRABLE EFFECTS OF QUALITY IMPROVERS
Figure 1 Principle of grinding cement clinker with (a) and Without (b) SBS
2511 GA
PRINCIPLE MECHANISMS AND DESIRABLE EFFECTS OF QUALITY IMPROVERS
PACKING & DOSAGE
SBS 2511 GA is available in 250 kg containers.
The dosage depends on the type of cement used:.