AAC block making machine line
AAC is a kind of light cellular silicate product. The main material is based on Silicon materials ( sand, fly ash, gangue contains silicon)and Calcium(cement and lime), mixed with the foaming agent (Aluminium powder), after batching, mixing, pouring,pre-curing, cutting, steam (autoclaved), and another process, finally, get this lightweight concrete products.
Introduction of AAC block production line
1. Storing and supplying of raw materials of AAC blocks: All raw materials are carried into the factory by trucks, such as Fly ash, sand or lime, which are gathered in specified raw materials fields waiting for use. Sacks of cement and bulk cement are stored in the cement warehouse. Chemicals and aluminium powder are separately kept in chemical warehouses and aluminium warehouses. When used, these raw materials are carried into the workshop respectively.
2. Processing of raw materials: Fly ash, sand or limestone is sent into ball mills by vibration feeders and belt conveyors. Then fine powders of fly ash, sand or lime are pumped into a slurry tank. Quick lime is sent by vibrating feeder and belt conveyor into jaw crushers to crush. Crushed lime is sent into the lime silo by bucket elevator and then is transported into ball mills by screw conveyor. Fined materials are sent into a proportion bin by screw conveyor and bucket elevator.
3. Aerated block ingredients, stirring and casting: Flyash (or sand or stone powder )and waste slurry are measured in a measuring tank. After the measuring and mould are in their place, slurry stirring begins. The slurry temperature should reach about 40°c.
Transformation des matières premières
1. The cement is bulk cement, which is pneumatically transported to the cement storage bin by a bulk cement truck. The cement storage capacity considered in this design is 90t.
2. After the lime and gypsum are crushed by the jaw crusher by calculation, the elevator enters the storage bin, is fed by electromagnetic vibration, enters the mill, and the finely mixed ash is transported by the elevator to the ash storage bin for backup.
3. The sand is transported into the slurry storage tank through ball milling and water wet milling into a slurry storage tank, and after the slurry specific gravity required for production is reached, it is pumped to a stirring pouring machine through a slurry pump.
4. Aerated block’s procuring and cutting
(1)Ingredients pouring: After the materials are ready, measure them separately, mix and stir with a stirring pouring machine, add the metered and stirred aluminium powder suspension, stir for 30-45 seconds, and then pour into the mould.
(2)Cutting section: After pouring and foaming, the green body is statically stopped to a certain hardness (about 1.2-2h), that is, cutting is performed, and the green body is lifted to a steaming cart by a marshalling spreader, and then marled into a kettle
(3)Autoclave: After cutting the green bodies, they can be marshalled to a certain number by driving and then enter the autoclave for autoclaving.
Advantages of AAC block production line
1. Lightweight
The aerated concrete dry bulk density is generally 400-800kg/m3, equivalent to clay brick 1/3, normal concrete 1/5, lower than normal light-weight aggregate concrete and hollow brick, hollow clay brick. so, using aerated concrete as wall material can lighten the building’s weight, and then reduce the size of the building’s foundation, girder pillar etc. Structure, save building material and project cost, and improve the building shock resistance.
2. Good heat preservation performance
The aerated concrete inside has an abundance of tiny air holes, so it has good heat preservation performance, its coefficient of heat conductivity generally is 0.09-0.02W/(m.k), only 1/4-1/5 for clay brick, normal concrete 1/51/10. Usually,20cm thick aerated concrete wall heat preservation performance corresponds to 49cm normal clay brick wall, thus not only saving heating and cooling energy but also improving the building plane greatly using the coefficient.
3. Processability
The aerated concrete doesn’t use coarse aggregate, has good processability, can be sawed, dug, drilled and pinned, and also can be covered by suitable binding material, which gives favourable conditions to building operations.
4. Wide raw material source, high production efficiency, low energy consumption
The aerated concrete can be produced by sand, ore slag, fly ash, tailing ore, coal gange quick lime, cement etc. According to local actual conditions to determine variety and process, and can use industrial waste residue greatly. Aerated concrete has high production efficiency, a medium-scale AAC plant, annual per capita labour efficiency can reach 600m3, and some high degree automation can reach 900-1000m3, higher than clay brick (180m3) and concrete brick (500-800m3).
Its production energy consumption is low, and unit product energy consumption is only 50% for the same volume of clay brick. Although the industrial production history of aerated concrete in China is only 40 years, its classification already developed non-weight bearing block, weight-bearing block, heating preservation block, wall and roof boarding, widely used in industrial and civil building, has become a new type of rich vitality building material.
Raw material proportion:
| Nom | Unité | Proportion |
| Cendres volantes | % | 65-70 |
| Ciment | % | 6-15 |
| Citron vert | % | 18-25 |
| Gypse | % | 3-5 |
| Pâte de poudre d'aluminium (600 kg/m³) | 1/10000 | 8 |
| Taux d'eau et de matière | 0.60-0.65 | |
| Température de durcissement | °C | 36-40 |
| Name | Unité | Proportion |
| Sable | % | 55-65 |
| Ciment | % | 10-20 |
| Citron vert | % | 20-30 |
| Gypse | % | 2-3 |
| Pâte de poudre d'aluminium (600 kg/m³) | 1/10000 | 8 |
| Taux d'eau et de matière | 0.65-0.75 | |
| Système de moulage | °C | 35-38 |
| Aluminium mixing time | S | 30-40 |
