Technology

The technology of the production of the aerated concrete

The cellular concrete is comparatively new material: if the brick is more than 300 years old, the cellular concrete is not more than 100 years old. It is an artificial porous stone, which can swim in the water. It corresponds to all requirements of the normative documents applied to the construction materials in solidity, deformability, frost-resistance. Its heat-shielding qualities are 3-12 times higher than the brick has. A wall made of this material can "breathe" providing good microclimate in the room. But the cellular concrete unlike the timber having just the same qualities is notable for its fire and biological stability.

Non-autoclave aerated concrete as a type of the cellular concrete having all the merits of the latter has some advantages. The aerated concrete has high water resistance, atmosphere resistance and low water absorbing. The solidity of the non-autoclave aerated concrete increases during its whole service life.

There are many ways of the production of the aerated concrete, but all of them are divided into 2 main groups according to the technology of the production:

1. The technology of the production of the aerated concrete by mineralization of the foam.
2. The technology of the production of the aerated concrete by poring of the mortar (by air entraining method or aeration).

Please, pay attention to the compositions of the aerated concrete given below. These are real compositions for the production of the aerated concrete mixture in the conditions of a workshop of the LLC "Ecostroimaterialy".

The table of the raw components charges

and some physic-mechanical characteristics of the aerated concrete
(in re-calculation on 1m³)

Density of the aerated concrete in dry state, kg/m3	Consumption of raw components				Coef-ficient of thermal conductivity, Wt/m·K°	Com-pression resistance in 28 days of solidification,kgc/cm2	Frost-resistance, cycles	Water con- sumption, %
	Cement, kg	Sand, kg	Water, l	Frother, gram
250	220	-	200	600	0,055	3	unnorm.	7-9
400	350	20	250	600	0,1	12	25	6-8
500	390	60	250	500	0,12	16	25	6-8
800	400	320	320	400	0,18	35	35	5-7
900	460	370	300	400	0,22	45	35	5-7
1000	480	450	300	400	0,25	60	35	5-7

Note:

We produce non-autoclave aerated concrete according to the compositions given above. These compositions are also situated in the office of our foreman of the workshop for the production of the aerated concrete blocks. Our operators of the aerated concrete mixers, which produce aerated concrete on construction sites, also use these compositions.

Many producers of the equipment for the non-autoclave aerated concrete report about less than given in the table 1 consumption of the cement for 1m³ of the aerated concrete. Moreover the declared consumption can really take place! The trick is that the aerated concrete of just the same density but produced with less consumption of the cement will have proportionally lower solidity. Strictly speaking it is impossible to consider the equipment for the production of the aerated concrete form the point of view of the cement consumption. It can be compared with statement of the producer of the aerated concrete mixers that you can greatly economize on the cement while producing the concrete just on his mixer! In our opinion, given in the table correlation solidity-density is optimal. This is also proved by our five-year experience. Saving 100 kilos of the cement you can lose a profitable client. Of course, it's up to you to decide what is more important for you.

The minimum of the equipment necessary for the organization of the production of the aerated concrete by aeration of the mortar:

1. Turbulent aerated concrete mixer
2. Air compressor
3. Encasement