All considerations about the basics gidroalyumosilikatnyh materials and technology are valid for foam with some additions, caused by the peculiarities of physical and chemical processes for preparing these materials and performance requirements for them.
1. Due to the limited carrying capacity of the films obtained in the mass of foam bubbles can not add coarsely chopped fraction of burned rock with grain size 1 to 3 mm. All the materials included in the foamed silicate must be finely pulverized, their particles adhere to the walls of the foam bubbles and hydrated in such a position and harden, forming the finest partition microcells. It goes well with favorable moisture migration process occurring during drying due to fine-meshed structure of the material.
2. Mixed with foam and molded materials in a state of slurry a creamy consistency, and is particularly advantageous to use wet grinding binders burnt rock and slag ball mills with the introduction of these curing accelerators.
3. For higher mechanical strength is recommended to use the non-hydrated lime sipelku in the form of a hammer as a much more active form
4. Steamed foam has physical and mechanical properties, providing its use as thermal insulation, and the autoclave can be applied to the relevant structures with thermal insulation properties.
Frother type affects the water absorption, and hence on those properties which are connected with it -vodo- and frost. For the manufacture of foam from burned rocks is better to use kleekanifolnuyu emulsion or foaming agent HA, as the water absorption material to them is lower.
As curing accelerators used additives gypsum, sodium sulfate and water glass, with a very good effect combined additives.
The addition of sodium silicate It reduces the weight of decadence and the possibility of cracking due to incomplete hydration of lime that should be attributed to slowing the additive caustic lime hydration process. Weights supplemented with waterglass not provide effervescence and their products can be placed in an autoclave or chamber almost immediately after production, t. E. In the production do not need extra space for holding product to heat treatment.
The addition of an acidic granulated blast slag improves the mechanical strength, but at the same time is a weighting addition of the bulk density gets higher by 8-10%.
In tests of the waste heaps of burned rocks Ziminka mines Redakovo North and “Pioneer” four optimal composition of masses for the production of foam concrete (Table. 82, 83) have been chosen.
as kleekanifolnuyu foaming agent used, the emulsion is prepared by a conventional method, wherein, per 1 kg of the binder was taken 20 g of the emulsion, and 0.7 liters of water, which is 1 m3 foam: wood glue-1,2 kg, 0,6 kg rosin- ; sodium hydroxide solution, 1.2 l.
The emulsion is produced separately and foamed in penobetonomeshalke, which is then fed to the prepared mortar in a mortar with aluminum silicate mass.
Institute Kuzniishahtostroi in 19R8, the oyla produced a pilot batch of reinforced aerated concrete panels type JA floors 30 and foam partition plates size 100X400X mm using mine waste heaps of burned rocks North.
High durability and frost resistance of these plates gave reason to recommend .ispytannye concrete formulations for the manufacture of wall panels in the technological scheme (Fig. 78) described below.
Sand from burned rocks with particle size grains of 1-3 mm, produced at the crushing and grinding plant with a fractionation through a receiving hopper and conveyor belt bucket elevator is delivered to the drying compartment, equipped with Valium dryer type SM-45.Part of the dried sand is milled in a ball mill and CM 267 via an elevator system falls into three bins with dispensers located above penobetonomeshalkoy mixer and dry 500 L capacity. Two of them are busy with sand and ground nagashenoy lime, which is prepared in a separate crushing and grinding plant, immediately adjacent to the shop. The Booker lime and cement can be submitted, if necessary, produce foam, where the sand of burned rocks plays the role of an active filler. Foam mass is directed by air tube into the trolley with a cable, then the cable using the hoist moving along the monorail, is transported to the stand to place the fill shapes are on autoclave trolleys. Bloodthirsty foam concrete form coming into the autoclave in diameter
Fig. 78. Technological scheme of production of foamed silicate and autoclaved aerated concrete of burned rocks -reception apparatus; 2 -kovshovye elevators; 3 -sushilny drum; 4 ball joint mill; 5 -bunkera; 6 -dozatory; 7 -suhoy mixer; 8 -penobetonomeshalka; 9 -rukavnaya estrus; 10 Trolley with Kübel; -telfer and monorail; 12 -kyubel; 13 -avtoklav; 14 -vagonetka cools with products; 15 -kran-beam; 16 -molotkovaya crusher for lime