With the acceleration of economic construction, especially the development of the power industry, a large amount of fly ash will be generated. In order to make full use of waste resources, protect land and the environment, it is particularly important to comprehensively develop and use fly ash. After a long-term demonstration study and adjustment and perfection in practical application, the "high-volume fly ash non-fired brick technology" has been successfully developed. This technology can use a large amount of fly ash, the amount of which reaches more than 80% (including aggregate), and opens a new way for a large number of fly ash digestion and utilization.
High content fly ash non-fired bricks are produced by using fly ash as the main raw material, adding a small amount of cement, additives and water, rolling, aging, stirring with a roller, forming under pressure, and dipping and curing. The quality of its products has been tested by the national quality inspection station, and it has reached the first-class requirements of GB5101 sintered ordinary clay bricks. After many years of inspection, the product's durability has not been found to reduce strength, swell, corner, and chalk.
I. Raw materials
The main raw materials for the production of autotrophic waste slag bricks are industrial waste slags such as fly ash, coal gangue, slag, steel slag and various waste bricks, stone powder, river sand, various tailings, etc., the amount of which reaches 80% (including aggregate ) Above, from various power plants, coal mines, thermal power plants, steel plants, stone plants. Other auxiliary materials are lime, cement, gypsum, additives, etc.
2. Forming mechanism
Fly ash, coal gangue, slag and other industrial waste residues contain relatively high silica, alumina, and iron oxide. After the raw materials are mixed and rolled, they are fully hydrated to form silicon and aluminum glass bodies.This glass body is oxidized after hydration. Calcium combines and produces a chemical reaction, called "volcanic ash reaction". The chemical equation is as follows:
Hydrate Active Substance
The hydrated silicon (alumino) calcium calcium silicate in the chemical reaction is a colloidal glass body.This colloidal glass body is not stable, but under the action of additives, it will gradually solidify with the continuous reaction over time, forming a high-strength network. The structure, combined with the reasonable allocation and maintenance of raw materials, has formed the strength of autotrophic bricks.
3. Production process
The production process of autotrophic waste bricks is very simple, and the process is as follows:
Loading machine → roller mixer → belt conveyor → brick press → brick blank → maintenance → finished product → delivery
Under normal circumstances, 500 kg of raw materials are mixed into a 0.5m3 roller for 6-8 minutes. The raw materials are sent to the storage hopper and flow into the feeder. The brick press presses the bricks at a speed of 1800-2000 blocks per hour, and is manually picked up. On the flat car, transported to the brick storage factory,
There are no gaps between the bricks, the stack height is 15 layers, the natural curing is 10-15 days, and the finished product can be delivered.
4. Technical indicators
After testing by the "Institute of Engineering Materials and Products of the Chinese Academy of Building Sciences", the self-cultivated waste slag brick has excellent performance, its mechanical properties can reach 100 # -200 #, and its appearance quality is first-class.
Flexural strength 26Kg-40Kg / cm2
Water absorption 12.2% -13%
Freeze-thaw: After 15 repeated freeze-thaw cycles, the strength is enhanced and the appearance quality is unchanged.
V. Ancillary equipment and production capacity
A complete set of production equipment includes brick presses, rollers, and feeders. The total power required is 42.07 kilowatts, and the power required for normal operation is 34 kilowatts. It has 9 production workers, a total area of 1600-3000m2, and a plant area of 100. -200m2, brick machine produces 1800-2000 bricks per hour, with an annual output capacity of 5-8 million bricks.
Cost and Benefit Analysis
The prices of materials are different in different regions, and the costs are different. Taking a coal mine as an example, the industrial waste slag is gangue slag after power generation from coal gangue. The following four parts are used to calculate the cost of raw materials, electricity costs, worker wages, and equipment depreciation:
Fly ash: 5-20 yuan / ton (including freight on board) Natural curing brick: Fly ash each brick accounts for 2.5 kg aggregate size (3-5 mm) accounts for 2.5 kg
Normal temperature steaming and high pressure steaming depend on the actual proportion of raw materials.
Cement: 220-300 yuan / ton (including freight) Cement accounts for 3-4 per brick. That is 8-10% of the total raw materials.
Electricity fee: 0.7-1 cents / block
Additives: 0.1 points / block
Equipment depreciation: 0.2 cents / block
After accounting, a company's fly ash production of self-cultivating waste slag bricks cost 8.5-9 cents / block for the above four parts, the test performance of the bricks reached level 10 and above, the local clay brick sales price is 15 cents / block, and the annual output is 2400- Calculated for 26 million bricks, the net profit of each brick is more than 6 cents, and the annual profit is more than 1.5 million, and the investment can be recovered in the same year.In addition, self-supporting waste bricks are used as waste residues, and can enjoy a series of national preferential policies, and can be exempt from income tax .
Seven. Characteristics of self-supporting waste bricks
1. Utilize the main raw materials of various industrial waste residues with an content of more than 80% (including aggregates), turn waste into treasure, and turn harm into profit.
2. The self-cultivation waste slag project has extremely competitive advantages. At present, the country strictly limits the production of clay bricks. The bricks do not use clay as raw materials to protect good fields and cultivated land.
3. No need for roasting, no kiln and steam curing kettle, environmental protection and energy saving. (Steam curing at room temperature is better than natural curing)
4. Mechanized production, the production process is simple, easy to master, and can be used in various places.
5. Because it is pressed and formed by a brick machine in the mold cavity, the appearance of the brick is very regular, and its various technical indicators are better than clay sintered bricks, steam-cured slag, and lime sand bricks.
6. In addition to the standard two or four bricks, using the "autotrophic waste slag bricks" technology can also produce eighty-five porous bricks, ninety-five porous bricks, hollow blocks and other building material products.
7. At present, of all the technologies for the production of building materials using industrial waste residues, the self-supporting waste residue brick project has the least investment and quick results.
Xinzhong Machinery is a joint-stock enterprise focusing on production machinery, integrating scientific research, production and sales. The company area is located in Zhengzhou Mazhai Economic Development Zone, covering an area of 60,000 square meters, with more than 35,000 square meters of standard workshops, more than 180 main processing equipment, and more than 1,000 online employees. Mainly produces ore powder ball press , hydraulic ball press , briquette ball press , dry powder ball press , desulfurized gypsum ball press , fire-free brick machine , road tile machine , sand making machine , ball mill , Raymond mill , Impact crusher and other products. Welcome new and old customers to visit and guide.