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:.