Production of Autoclaved Aerated Concrete Blocks from 600 to 650 kg/M3 Density
Main Components (Raw Materials) and Quantity per Cubic Meter
- Water - 200 - 280 Ltrs
- Ordinary Portland cement (OPC 53 Grade) – 90-110KG
- Quick Lime - 40-60KG
- Gypsum - 5-10KG
- fillers (Fly ash/Fine Sand) – 450 – 550KG
- Aluminum powder – 400-500Gms
- Additives – Quantity depends on raw material properties
Water for concrete mixture shall of any suitable drinking water. It is preferable to water from surface sources, unsalted, soft or medium hardness. It is also preferred to provide the required amount of water heated to a temperature of 40-50 º C for best results.
- Portland Cement
Virtually all of Ordinary Portland cement (OPC 53 Grade) suitable for the production of aerated lightweight concrete. Cement should be Fresh, Lumps free. Preferred to use good standard brands.
- Quick Lime
Quick Lime powder required for the AAC production. It is a main binder. Higher purity gives better result..
Gypsum is commonly used as a mineral additive in production of autoclaved aerated concrete (AAC)
As part of concrete mix Fly ash / Fine Silica Sand can be used as filler.
Fly ash / Pond Ash is from Thermal Power Plants (Fly ash is Silica rich product, which is industrial waste obtained from thermal power plant). Also fine silica sand can be used as filler.
- Foaming Agent
Small quantity of Pure Aluminum Powder is used for Foaming of concrete.
Just like other concretes, Additives such as Activators / Accelerators are used to improve and stabilize the quality of final product.
Process of production -
- Measured quantity of water is poured in primary slurry mixer.
- Measured quantity of Fly ash is added in primary slurry mixer. Mixed well and checked the density of slurry. To obtain the desired density,need to add more water or Flyash.
- Pour desired quantity of prepared slurry in to main mixer.
- Desired quantity of Cement is mixed with fly ash slurry.
- Desired quantity of Lime and Gypsum are added in mixer. Mix for 1-2Min
- Additives are poured in mixer.
- Mixture is heated with the help of steam up to required temperature.
- Aluminum Powder premixed with small quantity of water is added in Mixer. Mix for 15-30Seconds.
- Prepared mixture is poured into the molds.
- After filling, mold moves towards pre curing area
- In filled mold, concrete slurry rises (just like Bread) and volume increases up to desired height in 15-20 Minutes.
- In 2-4 Hrs. raised concrete gets its initial strength and mold panels are removed for cutting process.
- Then this concrete “cake” is sliced in required sizes Horizontally and then Vertically with the help of cutting machines.
- After cutting the mold base trolley is pushed inside the Autoclave.
- In autoclave steaming process is done with pressurized steam. Typically 12KG pressure. Depending on raw material properties, This cycle takes approximately 12 hours.
- After completing steaming (autoclaving) process, hardened Blocks are removed and shifted to storage area. These are ready blocks. and can be shipped immediately.