Product Description
WHAT IS AAC?
The AAC production process includes raw material preparation, batching and mixing, pouring, precuring, cutting, autoclaving, and packing. With decades of experience in serving the AAC blocks production machinery industry, we can supply customers with quality AAC block production lines with capacity ranging from 80,000m3 to 40,000m3 per year.
Chart 1 the parameter of the processes | Processes | Parameter |
| Mixing period | 5-6 minutes |
| Pouring slurry temperature | 40-45ºC |
| Cake curing time | 2.5-3.0h |
| Cake curing temperature | 45~55ºC |
| Cake strength after curing | 0.15~0.18MPa |
| Autoclaved curing system Before-after autoclave | 0.5h |
| Vacuumize | 0.5h(0~-0.06MPa) |
| Listing pressure | 1.5h(-0.06~1.3MPa) |
| Constant pressure | 8h(1.3MPa) |
| Releasing pressure | 1.5h(1.3~0MPa) |
| total | 12h |
RAW MATERIALS
Siliceous materials : Sand / Fly ash / Tailings containing silicon / Ceramic waste
Calcareous material: Lime block + cement + gypsum
Others: Aluminum powder paste
THE ADVANTAGES OF AAC:
1. Low density : Can be 325kg /m3
2. Good thermal insulating properties
3. Cost few time to build, saving time
4. Easy to operate , saving labor cost
5. Good performance of preventing fire
6. Good sound-insulation properties
7. Durable , anti-seismic , recyclable
CUTTING SYSTEM
Special cutting design : All the steel wire columns are fixed on two main oblique beams of cutting machine and each pair of the columns is used to fix only one steel wire , so that the horizontal cutting machine can avoid the settlement cracks problem in thin block and panel cutting , and achieve the minimum horizontal cutting thickness of 50MM block out of a whole mould. The integral swing frame of the vertical cutting machine can ensure the side plate replacement , the cutting action can be synchronized with ferry replacement. With automatic detection system . the broken wire can be timely detected.
PACKING SYSTEM
Automatic packing system can realize the automatic rotation stacking and splicing of blocks and realize the packing function with pallet or non-pallet. The stacking specification can realize 1.2m×0.6m\ 1.2m×1m\ 1.2m×12m\ 1m×0.6m multiple stacking , and the height of the stacking can be 1.2m, 1.5m , 1.8m and 2.4m.
AAC FINAL PRODUCTS
1.Product classification Product classification is according to national standards GB/T 11968-2006 AAC block, also can be according to user's requirements to produce product with special specifications size. Chart 2 Specification & Index
| Name | AAC block |
| Weight | 300~600 Kg/m3(control led by formula) |
| After autoclave compressive strength | average value≥3.5MPa, Min. value<=2.8Mpa |
| Drying shrinkage value | Measured under condition of rapid method≤0.8mm/m;Measured under condition of standard method≤0.5mm/m |
| Frost-resistance | After the cycle of freezing and thawing for 15 times,weight loss≤ 5%,strength loss≤ 20% |
| Coefficient of thermal conductivity | ≤0.14~0.16W/m.k |
1.2 The block is classified by compressive strength and volume density. Strength level: A1.0, A2.0, A2.5, A3.5, A5.0, A7.5, A10.
Dry density level: B03, B04, B05, B06, B07, B08. 1.3 Block level The block is divided into high-class(A), first-class(B), qualified product (C) according to the size variation, appearance quality, dry density, compression strength & frost-resistance.
1.4 AAC Block indicator Chart 3 Size variation& appearance | Project | Indicator |
High-class
(A) | Qualified product
(B) |
Permissible variation of dimension
mm | Length | L | ±3 | ±4 |
| Width | B | ±1 | ±2 |
| Height | H | ±1 | ±2 |
| Missing angle | The min. size not more than /mm | 0 | 30 |
| The max. size not more than /mm | 0 | 70 |
| Missing angle no. larger than the above size, not more than | 0 | 2 |
| Crack length | The crack length through one edge and two surfaces not more than crack directional size sum on crack surface | 0 | 1/3 |
| The crack length of any surface can not be larger than crack directional size | 0 | 1/2 |
| The cracks larger than the above size, not more than | 0 | 30 |
| The depth of cracking, sticking, damage can not be more than/mm | 0 | 1030 |
| Plain bending | Not allowed |
| Surface porosity, lamination crack | Not allowed |
| Surface oil | Not allowed |
Chart 4 Cubic compression strength for block | Strength level | Cubic compression strength (MPa) |
| Average not less than | Single group min. not less than |
| A1.0 | 1.0 | 0.8 |
| A2.0 | 2.0 | 1.6 |
| A2.5 | 2.5 | 2.0 |
| A3.5 | 3.5 | 2.8 |
| A5.0 | 5 | 4.0 |
| A7.5 | 7.5 | 6.0 |
| A10.0 | 10 | 8.0 |
Chart 5 Dry density for block(kg/m3) | Dry density level | B03 | B04 | B05 | B06 | B07 | B08 |
| Dry density | High-class (A)≤ | 300 | 400 | 500 | 600 | 700 | 800 |
Qualified product
(B)≤ | 325 | 425 | 525 | 625 | 725 | 825 |
Chart 6 Strength level for block | Dry density level | B03 | B04 | B05 | B06 | B07 | B08 |
| Strength level | High-class (A)≤ | A1.0 | A2.0 | A3.5 | A5.0 | A7.5 | A10.0 |
Qualified product
(B)≤ | A2.5 | A3.5 | A5.0 | A7.5 |
No. | Index content | unit | Index value |
I | Name |
| AAC block |
Production scale(annual capacity) | m³ | 150,000 |
Specification(cake: 4.2×1.2×0.6) | m | China national standard(GB) |
II | Working system(three-shift continuous weekly production) |
| 300 days / year 22.5 hours / day 7.5 hours / shift |
III | Main raw material consumption |
|
|
1. sand | Ton / year | 65000 |
2.lime | Ton / year | 15800 |
3. gypsum | Ton / year | 2800 |
4.cement | Ton / year | 9300 |
IV | Total capacity (without ball mill power) | KW | ≈630 |
V | Annual power consumption | 10,000ＫＷ.h | ≈260 |
VI | Annual water consumption | Ton | ≈57800 |
VII | Annual gas consumption | Ton | ≈22500 |
VIII | Single-shift producing operators | people | 6 |
Single-shift auxiliary personnel (including forklift and boiler gas distribution ) | 10 |
IX | Total plant construction area | hectare | ≈30 |
Construction area | m2 | ≈7000 |
Storage covering | m2 | ≈6000 |
No. | Index content | unit | Index value |
I | Name |
| AAC block |
Production scale(annual capacity) | m³ | 200,000 |
Specification(cake: 4.8×1.2×0.6) | m | China national standard(GB) |
II | Working system(three-shift continuous weekly production) |
| 300 days / year 22.5 hours / day 7.5 hours / shift |
III | Main raw material consumption |
|
|
1. sand | Ton / year | 86600 |
2.lime | Ton / year | 21100 |
3. gypsum | Ton / year | 3800 |
4.cement | Ton / year | 12400 |
IV | Total capacity (without ball mill power) | KW | ≈800 |
V | Annual power consumption | 10,000ＫＷ.h | ≈320 |
VI | Annual water consumption | Ton | ≈76400 |
VII | Annual gas consumption | Ton | ≈30000 |
VIII | Single-shift producing operators | people | 6 |
Single-shift auxiliary personnel (including forklift and boiler gas distribution ) | 10 |
IX | Total plant construction area | acre | ≈7.5 |
Construction area | m2 | ≈7000 |
Storage covering | m2 | ≈8000 |
No. | Index content | unit | Index value |
I | Name |
| AAC block |
Production scale(annual capacity) | m³ | 250,000 |
Specification(cake: 5.0×1.2×0.6) | m | China national standard(GB) |
II | Working system(three-shift continuous weekly production) |
| 300 days / year 22.5 hours / day 7.5 hours / shift |
III | Main raw material consumption |
|
|
1. sand | Ton / year | 108300 |
2.lime | Ton / year | 26300 |
3. gypsum | Ton / year | 4700 |
4.cement | Ton / year | 15500 |
IV | Total capacity (without ball mill power) | KW | ≈800 |
V | Annual power consumption | 10,000KW.h | ≈390 |
VI | Annual water consumption | Ton | ≈94900 |
VII | Annual gas consumption | Ton | ≈37500 |
VIII | Single-shift producing operators | people | 6 |
Single-shift auxiliary personnel (including forklift and boiler gas distribution ) | 10 |
IX | Total plant construction area | hectare | ≈35 |
Construction area | m2 | ≈7500 |
Storage covering | m2 | ≈8500 |
No. | Index content | unit | Index value |
I | Name |
| AAC block |
Production scale(annual capacity) | m³ | 300,000 |
Specification(cake: 6.0×1.2×0.6) | m | China national standard(GB) |
II | Working system ( three-shift continuous weekly production ) |
| 300 days / year 22.5 hours / day 7.5 hours / shift |
III | Main raw material consumption |
|
|
1. sand | Ton / year | 173200 |
2.lime | Ton / year | 42100 |
3. gypsum | Ton / year | 7500 |
4.cement | Ton / year | 24800 |
IV | Total capacity (without ball mill power) | KW | ≈1000 |
V | Annual power consumption | 10,000KW.h | ≈500 |
VI | Annual water consumption | Ton | ≈150600 |
VII | Annual gas consumption | Ton | ≈60000 |
VIII | Single-shift producing operators | people | 6 |
Single-shift auxiliary personnel (including forklift and boiler gas distribution ) | 10 |
IX | Total plant construction area | hectare | ≈50 |
Construction area | m2 | ≈10000 |
Storage covering | m2 | ≈13500 |
No. | Index content | unit | Index value |
I | Name |
| AAC block |
Production scale(annual capacity) | m³ | 400,000 |
Specification(cake: 6.0×1.5×0.6) | m | China national standard(GB) |
II | Working system ( three-shift continuous weekly production ) |
| 300 days / year 22.5 hours / day 7.5 hours / shift |
III | Main raw material consumption |
|
|
1. sand | Ton / year | 129900 |
2.lime | Ton / year | 31600 |
3. gypsum | Ton / year | 5600 |
4.cement | Ton / year | 18600 |
IV | Total capacity (without ball mill power) | KW | ≈1000 |
V | Annual power consumption | 10,000KW.h | ≈460 |
VI | Annual water consumption | Ton | ≈113500 |
VII | Annual gas consumption | Ton | ≈45000 |
VIII | Single-shift producing operators | people | 6 |
Single-shift auxiliary personnel (including forklift and boiler gas distribution ) | 10 |
IX | Total plant construction area | hectare | ≈45 |
Construction area | m2 | ≈9200 |
Storage covering | m2 | ≈10000 |
Process period
Mixing period: 5-6 minutes
Pouring slurry temperature: 40-45℃
Cake curing time: 2.5-3.0h
Cake curing temperature: 45～55℃
Cake strength after curing: 0.15～0.18MPa
Autoclaved curing system
Before-after autoclave: 0.5h
Vacuumize: 0.5h(0～-0.06MPa)
Listing pressure: 1.5h(-0.06～1.3MPa)
Constant pressure: 8h(1.3MPa)
Releasing pressure:1.5h(1.3～0MPa)
total: 12h
Process engineering brief
(1)The lime and gypsum will be crashed and ball milled after entering the factory, batch production for this section working system. The raw materials is continuous crashed into grain which granularity is less than or equal to 25mm, and then be put in the storage respectively through 3-pass splitting by bucket elevator. Lime and gypsum-grain will be fed in proportion through speed belt scale and into ball mill for mixture levitation through the respective baiting splitting, When the fineness reached 3500 ~ 4000cm2 / g, the lime and gypsum-grain will be sent into cement silo through bucket elevator for storage.
(2) The sand is transported to stacking place by dump truck for use.
(3) Sand will be transported to the hopper by loader car, then after measuring be transported to wet ball miller for milling by the belt conveyor, milled to mortar and be transported to storage tank stand-by through beating pool.
(4)Mortar poured into slurry measurement through slurry pump, the cement transported into powder measurement through screw conveyor; The measured mortar, cement poured into pouring mixer according to ratio order for mixing, the amount of steam passed into mixer based on process requirements, slurry temperature in the mixer reached about 40 ~ 45 ℃, mixing time is about 3 ~ 4mins, open the lower valve of aluminum paste mixer, make it flow into pouring mixer for mixing, mixing time is not more than 40s, then the slurry poured into mold. The whole period is about 5 to 6mins.
(5) The poured mold car transfers to curing area for gas-forming & initial setting, temperature in curing room is about 40 to 45 ℃, curing for 150 to 180mins, the mold car is pull out of curing room when reached the cutting strength.
(6)Mould will be transported to the cutting area when the curing reach to cutting requirements, turning table separates the mould and turns the cake to 90°spaced on the cutting car. The car carried cake achieves six sides cutting through horizontal and vertical cutting process(length±3mm～width±1mm～±1mm).
(7) Put the cake on the semi-finished product turning table by crane after cutting, the cake turned to 90 ° by turning table to be peeled the bottom & top leather, then be turned again to original position, next be stacked on the steam curing car by the semi-finished product stacker, marshaled steam curing car be put into the autoclave for high temperature (200 ℃), high pressure (1.3 MPa), autoclave (about 12 hours). Sweep gas in the autoclave be sent to curing area by the pipe.
(8) Finished curing cake will be combined, divided, transfer and packaging after classified placing, separating and clamping treatment. Then sent the after-package cake to the storage yard by forklift. Finished product separated bottom plates will be transported to compound die area by curing car for mould car compounding. After cleaning and oil brushed, the curing car will be poured for re-use. Then back to the curing car and process the autoclave curing after stacking and grouping.
(9) The recycled waste in production can be made into waste slurry by waste mixer , the stored waste slurry can be reused with raw material.
1. Cement
Producing AAC block adopts lime-cement mixing calcium system, can use standard 425# cement, and is according to technical requirements GB 175 General Silicate Cement. Before entering factory with manufacture quality certification, The cement should be used in sequence. Cement technical requirements as blow:
(1) Free CaO content should be not more than 1.5%, CaO content is 60%.
(2) NaCl & KCl content should be not more than1%~1.5%.
(3) Specific surface area 2500~3500cm3/g.
(4) Volume stability is qualified.
(5) Setting time initial setting 1~3h final setting 3~6h.
2. Sand
It should be according to the standard JC/T 662 Sand for Silicate Building Products to select. Generally, the higher quartz content in the sand, the better AAC block quality.
Chart 2-1 Main technical index for sand
Name | SiO2% | K2O+Na2O% | Organic matter | Mica% | SO3% | Mud% | Moisture content% |
Grade |
High-class | ≥85 | ≤1 | Qualified | ≤0.5 | 1 | 3 | 8 |
Firs-class | ≥75 | ≤3 | 5 |
Qualified product | ≥65 | ≤5 | ≤1 | 2 | 8 |
Chart 2-2 Grain composition for sand
Name | Content,% |
Grade | High-class | First-class | Qualified product |
2.5～5.0(round hole) | 0 | 0 |
1.25～2.5(square hole) | 10 | 10 |
0.16～0.25(square hole) | 60 | 45 |
＜0.16(square hole) | 30 | 45 |
3. Quick lime
Lime is also one of the main raw material. Its function is coordinating with cement to provide effective calcium oxide, than makes it working with SiO2, Al2O3 from silica material under hydrothermal condition to generate hydrated calcium silicate. So it should be according to JC/T621 Quick Lime for Silicate Building Product standard. Effective calcium oxide content should be more than 65%, the best is more than 80%.
4. Aluminum paste(powder)
Aluminum paste is according to JC/T 407 Aluminum Paste for AAC standard. Aluminum powder should be according to the current national standard, the requirements of Aluminum Powder Part 2: Ball Mill Aluminum Powder GB/T 2085. 2.
5. Gypsum
Gypsum is a modifier during gas processing in the AAC. The regulating effect of gypsum mainly reflects in deferring the speed of quick lime digesting & slurry thickening. Gypsum should be according to the current national standard, the requirements of Natural Gypsum GB/T 5483. The main chemical compositions of gypsum are CaSO4,CaSO4·2H2O>70%.
6. Water
According to the standard, water ratio is advisable to 0.60.
Chart 2-3 water quality requirement
Content | pH | Cl- (mg/L) | SO42-(mg/L) | Na+ +K+(mg/L) | K+ (mg/L) |
Operating range | 6~9 | ＜600 | ＜1000 | ＜450 | ＜100 |
1.Product classification
Product classification is according to national standards GB/T 11968-2006 AAC block, also can be according to user’s requirements to produce product with special specifications size.
Chart 1 Specification & Index
●Name | AAC block |
●Weight | 300～600 Kg/m3(control led by formula) |
●After autoclave compressive strength | average value≥3.5MPa, Min. value≦2.8Mpa |
●Drying shrinkage value | Measured under condition of rapid method≤0.8mm/m；Measured under condition of standard method≤0.5mm/m |
●Frost-resistance | After the cycle of freezing and thawing for 15 times，weight loss≤ 5%，strength loss≤ 20% |
●Coefficient of thermal conductivity | ≤0.14～0.16W/m.k |
1.1 Specification
Block specification is shown in Chart 2.
Charts 2 Block specification (mm)
Length L | Width B | Height H |
600 | 100 120 125 | 200 240 250 300 |
150 180 200 |
240 250 300 |
Remark: It should be resolved through consultation by the two sides if need other specifications. |
1.2 The block is classified by compressive strength and volume density.
Strength level: A1.0, A2.0, A2.5, A3.5, A5.0, A7.5, A10.
Dry density level: B03, B04, B05, B06, B07, B08.
1.3 Block level
The block is divided into high-class(A), first-class(B), qualified product (C) according to the size variation, appearance quality, dry density, compression strength & frost-resistance.
1.4 AAC Block indicator
Chart 3 Size variation& appearance
Project | Indicator |
High-class | Qualified product |
(A) | (B) |
Permissible variation of dimension | Length | L | ±3 | ±4 |
mm | Width | B | ±1 | ±2 |
| Height | H | ±1 | ±2 |
Missing angle | The min. size not more than /mm | 0 | 30 |
The max. size not more than /mm | 0 | 70 |
Missing angle no. larger than the above size, not more than | 0 | 2 |
Crack length | The crack length through one edge and two surfaces not more than crack directional size sum on crack surface | 0 | 1月3日 |
The crack length of any surface can not be larger than crack directional size | 0 | 1月2日 |
The cracks larger than the above size, not more than | 0 | 30 |
The depth of cracking, sticking, damage can not be more than/mm | 0 | 1030 |
Plain bending | Not allowed |
Surface porosity, lamination crack | Not allowed |
Surface oil | Not allowed |
Chart 4 Cubic compression strength for block
Strength level | Cubic compression strength (MPa) |
Average not less than | Single group min. not less than |
A1.0 | 1 | 0.8 |
A2.0 | 2 | 1.6 |
A2.5 | 2.5 | 2 |
A3.5 | 3.5 | 2.8 |
A5.0 | 5 | 4 |
A7.5 | 7.5 | 6 |
A10.0 | 10 | 8 |
Chart 5 Dry density for block(kg/m3)
Dry density level | B03 | B04 | B05 | B06 | B07 | B08 |
Dry density | High-class (A)≤ | 300 | 400 | 500 | 600 | 700 | 800 |
Qualified product | 325 | 425 | 525 | 625 | 725 | 825 |
(B)≤ |
Chart 6 Strength level for block
Dry density level | B03 | B04 | B05 | B06 | B07 | B08 |
Strength level | High-class (A)≤ | A1.0 | A2.0 | A3.5 | A5.0 | A7.5 | A10.0 |
Qualified product | A2.5 | A3.5 | A5.0 | A7.5 |
(B)≤ |
Chart 7 Drying shrinkage, freeze-proof, heat conduction
Volume density level | B03 | B04 | B05 | B06 | B07 | B08 |
Drying | · | 0.5 |
shrinkage value | Standardized method |
| /(mm/m) ≤ |
| Rapid method /(mm/m) ≤ | 0.8 |
Frost-resistance | Quality loss/% ≤ | 5 |
Frost-resistance /Mpa ≥ | High-class(A) | 0.8 | 1.6 | 2.8 | 4 | 6 | 8 |
Qualified product | 2 | 2.8 | 4 | 6 |
(B) |
heat conductivity coefficient (dry state)/〔W/（m•k）〕 ≤ | 0.1 | 0.12 | 0.14 | 0.16 | 0.18 | 0.2 |
Block drying shrinkage value is measured by standardized method & rapid |
method, decided by standardized method if the measured results conflict. |
