CN115925330A - Iron tailing high-performance water permeable brick and preparation method thereof - Google Patents

Abstract

The invention provides an iron tailing high-performance water permeable brick and a preparation method thereof. The iron tailing high-performance water permeable brick comprises the following components in parts by weight: 78 to 88 parts of sand-modified iron tailings, 10 to 15 parts of cement, 2 to 8 parts of fly ash, 0.3 to 0.8 part of cement polymer reinforcing agent and 0.20 to 0.30 part of water-cement ratio, wherein the preparation method comprises the following steps: s1: designing the iron tailing pavement water permeable brick material: considering the economic transport distance of the iron tailing water permeable bricks, determining that the use environment is a hot-summer and cold-winter area, and designing the bottom layer and the surface layer materials of the high-performance iron tailing water permeable bricks according to the A-level water permeability requirement; s2: replacing aggregate with iron tailings and improving: the iron tailings are cleaned to prepare the sand after impurity removal. The iron tailing high-performance water permeable brick and the preparation method thereof provided by the invention have the advantages that the iron tailing replaces aggregate, the production cost is also greatly reduced, the market competitiveness is better compared with the traditional water permeable brick, and the industrial popularization can be realized.

Description

A high-performance permeable brick for iron tailings and its preparation method

technical field

The invention relates to the technical field of permeable bricks, in particular to a high-performance permeable brick for iron tailings and a preparation method thereof.

Background technique

Iron tailings is a kind of composite mineral raw material, which is the waste residue _left after the iron ore has been ground and selected iron concentrate _{. 3.} Fe ₂ O ₃ , CaO, MgO, etc., among which the content of silicon and aluminum is relatively high, and more than 80% of the minerals are non-metallic minerals. After being treated with inorganic binders, they are used as building materials to achieve energy saving and efficiency, no waste and no waste. hazards, environmental protection, land conservation, tailings dam safety, green mine construction, and promote the sustainable development of mining enterprises.

In the prior art:

Disclosed is an all-solid waste permeable brick and its preparation method and application (application publication number CN113582635A, application number 202110872612.X). The present invention relates to the technical field of permeable bricks, in particular to an all-solid waste permeable brick and its preparation method application. The permeable brick includes a bottom layer and a surface layer, and the raw materials in the bottom layer include: 15-22 parts of solid waste-based sulfoaluminate cementitious material, 70-80 parts of steel slag; water-cement ratio 0.33; water reducing agent 3 ～4.4 parts; surface layer raw materials include: 15-22 parts of solid waste-based sulfoaluminate gelling material, 8-10 parts of iron tailings, 0.33 water-binder ratio, 3-4.4 parts of water-reducing agent.

Its disadvantages are:

(1), "The preparation of solid waste-based sulfoaluminate cementitious materials is to grind and homogenize limestone tailings, desulfurized gypsum, steel slag and aluminum ash, and then calcinate them in a kiln at 1220°C to 1300°C. 30-60 minutes to obtain solid waste-based sulphoaluminate cement clinker, and the obtained solid waste-based sulphoaluminate cement clinker is ground with 3% to 10% of desulfurized gypsum to obtain solid waste-based sulphoaluminate Cementitious materials." The proportions of limestone tailings, desulfurized gypsum, steel slag and aluminum ash are not clear enough, and the process is more complicated, and the production cost of permeable brick raw materials is relatively high.

(2) In the prior art, there have been studies using steel slag and iron tailings as aggregates to prepare permeable bricks. The particle size of steel slag is 5.0mm-20.0mm, and the particle size of iron tailings is 2.5mm-10mm. The proportions of different levels are not clear, and the quality is not easy to guarantee, so it is not conducive to sustainable development.

A permeable brick formula and its preparation process (application number 202111484313.5, application publication number CN114149215 A), the invention includes aggregate, cement, water, water reducer, silica fume and thickener, the content of which accounts for the weight of the total formula The percentages are: 80% for aggregate, 15% for cement, 4% for water, 0.15% for water reducer, 0.75% for silica fume, and 1% for thickener. A preparation process for permeable bricks, comprising: aggregate pretreatment; mixing process: take aggregate and mix water, then add thickener, cement, water reducer and silica fume while stirring, and stir for 2 minutes; forming process: mix Put the mixed material into the mold, and press it on the press with a static pressure of 25 MPa for 1 minute; maintenance: after molding, remove the mold and soak in water for 10 days.

Its disadvantages are:

(1) The aggregate is made of construction waste or steel slag. Does the composition of construction waste and steel slag meet the technical index requirements of the aggregate?

(2) How to screen construction waste. The graded aggregate of construction waste is composed of fine aggregate with a particle size of 1.20-4.80mm and coarse aggregate with a particle size of 4.80-9.50mm. The composition of each particle size The ratio is not specified.

(3) The particle size range of steel slag is not clear, and the proportion of each particle size in the gradation is not clear.

(4) After forming, remove the mold and soak in water for 10 days. The curing method adopts water soaking curing, which is not realistic enough to implement in the actual production line; the curing time is 10 days, whether it can guarantee to achieve the expected strength.

(5) The compressive strength and water permeability coefficient of permeable bricks are not clear, and the technical indicators are not clear.

A method for preparing high-strength sintered permeable bricks using copper tailings (application number 202110925598.5, application publication number CN 113683393 A), including in order to realize the effective utilization of copper tailings, making it the main component of permeable bricks, turning waste into treasure, The environmental pollution can be greatly reduced, and at the same time, significant economic and social benefits can be achieved. The present invention proposes a method for preparing high-strength sintered permeable bricks using copper tailings sand. The method includes the following steps: S1, lake sediment pretreatment, S2 , slime pretreatment; S3, preparation of permeable brick aggregate; S4, binder preparation; S5, stale; S6, compression molding; S7, sintering molding. The invention realizes efficient utilization of copper tailings, lake bottom mud and coal slime, and achieves the goals of environmental protection, energy saving and resource utilization. The high-strength sintered permeable brick prepared by the invention has the characteristics of high strength and high water permeability. The invention solidifies the heavy metals in the lake bottom mud, effectively reducing the heavy metal pollution of the original lake bottom mud.

Its disadvantage is

(1), "Lake bottom mud pretreatment, the lake bottom mud is left to stand for dehydration, so that its water content is 30-50%, then dried, sieved, and the products under the sieve are ball milled and homogenized after being baked to obtain In the lake sediment after pretreatment, the output of the lake sediment is low, "the lake sediment is left standing for 7 days, stirred once a day, and press-filtered to make the water content 35-45%; the baking The temperature is 105°C and dried for 2 hours; the ball mill is ground in a ball mill for 5-15 minutes, and the ball milling rate is 25.4r/min." The complexity of the process leads to an increase in cost, which makes the market competitiveness of industrialization promotion not strong;

(2), "The screening particle size and mass ratio of the permeable brick aggregate in step S3 are respectively: 10% to 30% for 1.18 to 4.75mm, 40% to 60% for 0.60 to 1.18mm, and 40% to 60% for 0.15 to 0.60mm 20% to 40%" has a wide range of particle size proportions, and it is not easy to guarantee the quality;

(3) In the expression "in step S6, the pressing pressure is 15-35 MPa", the pressure range is relatively large, and it is difficult to ensure the stability of the strength of the permeable brick.

(4), "In step S7, the sintering is: 0°C rises to 60°C at 0.5°C/min, 60°C rises to 300°C at 2°C/min, keeps warm for 60min, 300°C rises to 900°C at 3°C/min , hold for 60 minutes, 900°C rises to 950-1000°C at 0.5-1°C/min, hold for 30-150 minutes, and then cool down with the furnace." The complicated process will also increase the cost, and the market competitiveness is not strong.

Therefore, it is necessary to provide a new iron tailings high-performance permeable brick and its preparation method to solve the above technical problems.

Contents of the invention

The technical problem solved by the present invention is to provide a kind of iron tailings instead of aggregate and greatly reduce the production cost. Compared with traditional permeable bricks, it has better market competitiveness and can realize the high performance of iron tailings for industrialization promotion. Permeable brick and its preparation method.

In order to solve the above technical problems, the high-performance iron tailings permeable brick provided by the present invention includes the following components in parts by weight: 78-88 parts of iron tailings improved by sand and stone, 10-15 parts of cement, and 2-8 parts of fly ash , 0.3-0.8 parts of cement polymer reinforcing agent, and 0.20-0.30 parts of water-binder ratio.

Preferably, the following components are included in parts by weight: 83 parts of iron tailings modified by sand and gravel, 11 parts of cement, 5.45 parts of fly ash, 0.55 parts of cement polymer reinforcing agent, and 0.28 parts of water-binder ratio.

The present invention also provides a method for preparing iron tailings high-performance permeable bricks, which includes the following steps:

S1: Material design of iron tailings pavement permeable bricks: Considering the economic transportation distance of permeable bricks, determine the use environment is hot summer and cold winter regions, prepare high-strength and high-performance permeable bricks according to A-level permeable requirements, and design permeable brick bottom and surface materials;

S2: Replacement and improvement of iron tailings aggregates: Iron tailings are cleaned and sand-made by removing impurities, and then sieved to evaluate the particle size of iron tailings. According to the constructed permeable brick aggregate gradation improvement function model, machine-made sand, The broken stone is improved; the improvement of the aggregate gradation of the permeable brick is improved by the break function, and the break function is as follows:

y=Ax ^B , where, 4.75≤x≤9.5;

y=0.43x+1, wherein, 1.18<x<4.75;

y=0.53x+1, wherein, 0.30<x≤1.18;

y=Clnx+D, wherein, 0.075≤x≤0.30;

In the formula: x represents the aggregate particle size, y represents the sieving pass rate (%), and A, B, C, and D are regression coefficients.

S3: Mixing of permeable brick bottom material: First, add iron tailings modified aggregate, cement, cement polymer enhancer, and fly ash into the concrete mixer, stir for 35-60 seconds to mix well, and then add the mix ratio Mix half of the water for 45-60 seconds. When the mixture reaches a uniform wet state, add the remaining half of the water and stir for 3-4 minutes to obtain the iron tailings permeable brick mixed base material;

S4: Mixing of permeable brick fabric: first add granite machine-made sand or quartz sand, cement, and cement polymer reinforcing agent into the concrete mixer, stir for 30-45 seconds to mix well, and then add half of the water in the mix ratio Stir for 45-50 seconds, when the mixture reaches a uniform wet state, add the remaining half of the water and stir for 2-3 minutes to get the iron tailings permeable brick mixed fabric;

S5: Vibration pressure forming: the prepared permeable brick mixed bottom material and fabric are transported to the bottom material bin and the fabric bin respectively through an inclined belt conveyor. First, the iron tailings permeable brick mixed bottom material is put into the mold for vibration and pressure Forming, then pressurize the fabric to the surface layer of the formed brick, set the static pressure at 18MPa±2MPa for pressurized molding to prepare permeable bricks;

S6: Maintenance: After the iron tailings permeable brick surface process is completed, use a spatula to smooth the surface, and send it to the maintenance workshop for standard maintenance and outdoor manual maintenance through the track. After the maintenance period is 28 days, it will leave the factory after passing the inspection.

Preferably, in said S1, the bottom layer and surface layer materials of the permeable bricks are designed according to the use environment in hot summer and cold winter regions, water permeability grade A, average flexural strength not less than 4.0Mpa, average split tensile strength The design shall not be less than 4.0Mpa, the length of the grinding pit shall not be greater than 35mm, and the anti-skid BPN value shall not be less than 60; the bottom material of the permeable brick shall be reinforced by iron tailings, machine-made sandstone, fly ash, cement, and cement polymer Agent composition, the particle size of machine-made sand and gravel improved iron tailings is 0.075mm ~ 9.5mm, machine-made sand and gravel improved iron tailings in the mixture: cement: fly ash: cement polymer reinforcing agent = 83:14:2.45:0.55 , the water-binder ratio is 0.28, and the amount of superplasticizer is 2% ± 0.2% of the total weight of cement and cement polymer reinforcing agent; the permeable brick surface layer is composed of granite stone machine-made sand, cement, and cement polymer reinforcing agent. Granite machine-made sand has a particle size of 1.18mm to 2.36mm. Granite machine-made sand in the mixture: cement: cement polymer enhancer = 95:4.35:0.65, water-binder ratio is 0.24; cement uses ordinary Portland cement, Its strength is not lower than 42.5; the grade of fly ash is not lower than grade II.

Preferably, in said S2, the iron tailings are used to replace aggregates and improve. First, the iron tailings are removed, cleaned, and screened through a water panning and screening machine, so that the stone powder and iron tailings are separated, and are evaluated by screening tests. The fineness modulus of iron tailings sand is 1.5. According to the aggregate gradation design of permeable bricks, machine-made sand and crushed stones are used for discontinuous grading to improve iron tailings. The particle size of 0.075mm-4.75mm improved mixture accounts for the proportion of the total aggregate. It is 10% to 15%, and the improved function model of the aggregate gradation of permeable bricks is improved by discontinuous function.

Preferably, the mixing of the base material of the permeable brick in S3 and the mixing of the surface of the permeable brick in S4 adopt separate and parallel mixing systems, and the mixing time of the base material is 30s to 60s earlier than that of the surface material.

Preferably, in the S5, the static pressure is set to 18 MPa for vibration molding, the vibration molding time is controlled between 20S and 25S, and the fabric color is colored and sprayed according to actual needs.

Preferably, in said S6, the maintenance includes standard maintenance and natural maintenance in the maintenance workshop, and the permeable brick vibratory pressure forming embryo body is sent to the maintenance workshop with a temperature of 20°C ± 2°C and a humidity of not less than 95% for 24 hours. Palletize iron tailings permeable bricks, continue manual maintenance in an outdoor environment, water twice a day, until the specified age of 28 days is maintained, and leave the factory after passing the inspection.

Compared with related technologies, the iron tailings high-performance permeable brick and its preparation method provided by the present invention have the following beneficial effects:

1. Iron tailings high-performance permeable brick material is a new type of cement product, which is formed by vibration and pressing, and belongs to the type of non-sintered brick. Iron tailings high-performance permeable bricks are used in public places such as sidewalks, non-motor vehicle lanes, roads with small road loads, parking lots, squares, etc. in the construction of "sponge towns". Permeable leveling layer, 100mm-150mm permeable base, 150mm-200mm permeable subbase, in order to better improve the collection and utilization of permeable water, DN50 PVC seepage pipes are installed in the permeable base, which can effectively divert permeable water into municipal drainage System; the iron tailings high-performance permeable brick has a rough surface and has very good anti-skid properties, which can improve the safety of driving and pedestrians; the permeable brick has a large internal gap, which can alleviate the urban heat island effect and absorb road traffic noise ;

2. The use of iron tailings and fly ash as the basic materials of permeable bricks plays a very good role in promoting "green mine construction", solid waste utilization, and sponge town construction, and can solve the problem of massive accumulation of iron tailings in mines and power plants Environmental protection, safety, operation management and other issues brought by fly ash;

3. The iron tailings are directly used as aggregates in the production line to produce permeable bricks. The aggregate gradation composition cannot meet the requirements of grade A of the permeable grade. According to the aggregate requirements designed for the bottom material of the permeable bricks, machine-made sandstone is used to improve the iron tails. Mine, so that the improved iron tailings mixed aggregate meets the aggregate design grading requirements, greatly improving the permeability of permeable bricks;

4. Iron tailings sand fineness modulus = 1.5, which belongs to ultra-fine sand, and because the iron tailings and fly ash mixed with iron tailings permeable bricks are relatively high, in order to improve the brick forming quality, vibration and static pressure phase are adopted Combined with high-pressure extrusion technology for secondary molding, it realizes the integrated production of iron tailings permeable bricks. It does not require roasting and does not produce any environmental pollution. It can consume iron tailings and fly ash in large quantities and realize the utilization of solid waste resources;

5. The production of iron tailings permeable bricks can be built on the spot around the iron tailings pond, which can reduce the transportation of iron tailings. The raw materials do not need to be sintered, and there is no sintering link in the production process. Iron tailings can also replace aggregates. Compared with traditional permeable bricks, it has better market competitiveness and can realize industrialization promotion by reducing production costs.

Detailed ways

The present invention will be further described below in combination with embodiments.

The invention provides high-performance permeable bricks for iron tailings, which include the following components in parts by weight: 78-88 parts of iron tailings modified by sand and stone, 10-15 parts of cement, 2-8 parts of fly ash, and cement polymer reinforcing agent 0.3-0.8 parts, water-binder ratio 0.20-0.30 parts.

The composition includes the following components by weight: 83 parts of iron tailings modified by sand and gravel, 11 parts of cement, 5.45 parts of fly ash, 0.55 parts of cement polymer reinforcing agent, and 0.28 parts of water-binder ratio.

The present invention also provides a method for preparing iron tailings high-performance permeable bricks comprising the following steps:

S1: Material design of iron tailings pavement permeable bricks: Considering the economic transportation distance of permeable bricks, determine the use environment is hot summer and cold winter regions, prepare high-strength and high-performance permeable bricks according to A-level permeable requirements, and design permeable brick bottom and surface materials;

S2: Substitution of iron tailings for aggregates and improvement: Iron tailings are cleaned and sand-made by removing impurities, and then sieved to evaluate the particle size of iron tailings. According to the aggregate gradation design of permeable bricks, machine-made sand and crushed stone are used to carry out the process. Improved, the function model of the improved iron tailings mixed bone adopts the discontinuous function to improve the particle size range from 0.075mm to 9.5mm;

S3: Mixing of permeable brick bottom material: First, add iron tailings modified aggregate, cement, cement polymer enhancer, and fly ash into the concrete mixer, stir for 35-60 seconds to mix well, and then add the mix ratio Mix half of the water for 45-60 seconds. When the mixture reaches a uniform wet state, add the remaining half of the water and stir for 3-4 minutes to obtain the iron tailings permeable brick mixed base material;

S4: Mixing of permeable brick fabric: first add granite machine-made sand or quartz sand, cement, and cement polymer reinforcing agent into the concrete mixer, stir for 30-45 seconds to mix well, and then add half of the water in the mix ratio Stir for 45-50 seconds, when the mixture reaches a uniform wet state, add the remaining half of the water and stir for 2-3 minutes to get the iron tailings permeable brick mixed fabric;

S5: Vibration pressure forming: the prepared permeable brick mixed bottom material and fabric are transported to the bottom material bin and the fabric bin respectively through an inclined belt conveyor. First, the iron tailings permeable brick mixed bottom material is put into the mold for vibration and pressure Forming, then pressurize the fabric to the surface layer of the formed brick, set the static pressure at 18MPa±2MPa for pressurized molding to prepare permeable bricks;

S6: Maintenance: After the iron tailings permeable brick surface process is completed, use a spatula to smooth the surface, and send it to the maintenance workshop for standard maintenance and outdoor manual maintenance through the track. After the maintenance period is 28 days, it will leave the factory after passing the inspection.

In the above S1, the bottom layer and surface layer materials of permeable bricks are designed according to the use environment in hot summer and cold winter areas, water permeability grade A, average flexural strength of not less than 4.0Mpa, and average split tensile strength of not less than 4.0Mpa, the length of the grinding pit is not more than 35mm, and the anti-skid BPN value is not less than 60. The design is required; the bottom material of the permeable brick is composed of iron tailings, machine-made sandstone, fly ash, cement, and cement polymer enhancer. The particle size of machine-made sand and gravel improved iron tailings is 0.075mm to 9.5mm. In the mixture, machine-made sand and gravel improved iron tailings: cement: fly ash: cement polymer enhancer = 83:14:2.45:0.55, water glue The ratio is 0.28, and the amount of water reducer added is 2% ± 0.2% of the total weight of cement and cement polymer reinforcing agent; the permeable brick surface layer is composed of granite stone machine-made sand, cement, and cement polymer reinforcing agent, and the granite stone machine-made The particle size of the sand is 1.18mm ~ 2.36mm, the granite stone machine-made sand in the mixture: cement: cement polymer reinforcing agent = 95:4.35:0.65, the water-binder ratio is 0.24; the cement uses ordinary portland cement, and its strength is not Lower than 42.5; the fly ash grade is not lower than Grade II.

In the above S2, the iron tailings are used to replace aggregates and improve. First, the iron tailings are removed, cleaned, and sieved through a water panning and screening machine to separate the stone powder from the iron tailings sand. The iron tailings sand is evaluated by a screening test. Fineness modulus = 1.5, according to the aggregate gradation design of permeable bricks, machine-made sand and crushed stone are used for discontinuous gradation to improve iron tailings, and the particle size of the improved mixture of 0.075mm to 4.75mm accounts for 10% of the total aggregate ~15%.

The mixing of the permeable brick base material in S3 and the permeable brick surface material in S4 adopts a separate parallel mixing system, and the mixing time of the base material is 30s to 60s earlier than that of the surface material.

In S5, the static pressure is set to 18MPa for vibration molding, the vibration molding time is controlled between 20S and 25S, and the fabric color is colored and sprayed according to actual needs.

Preferably, in said S6, the maintenance includes standard maintenance and natural maintenance in the maintenance workshop, and the permeable brick vibratory pressure forming embryo body is sent to the maintenance workshop with a temperature of 20°C ± 2°C and a humidity of not less than 95% for 24 hours. Palletize iron tailings permeable bricks, continue manual maintenance in an outdoor environment, water twice a day, until the specified age of 28 days is maintained, and leave the factory after passing the inspection.

In other embodiments, sand and gravel improved iron tailings in the bottom mixture: cement: fly ash: cement polymer reinforcing agent = 83:11:5.45:0.55, and the cement water-binder ratio is 0.28. In practice, iron tailings The fractal dimension fluctuates and varies, so the amount of each material varies within a certain range, of which: the amount of modified iron tailings mixed aggregate is 78% to 88%, the amount of cement is 10% to 15%, and the amount of fly ash is 2% to 8%. %, cement polymer reinforcing agent 0.3%-0.8%, water-binder ratio 0.20-0.30.

In the iron tailings sand replacement aggregate and improvement method in S2 in other embodiments, the sand and gravel aggregate used for improvement is not limited to machine-made sand and gravel. The sand and gravel in "Construction Pebbles and Crushed Stones" can be used to improve iron tailings and be used as aggregates for permeable bricks.

In other embodiments, the maintenance in S6 can adopt various maintenance methods, as long as the maintenance methods can meet the maintenance requirements.

Compared with related technologies, the iron tailings high-performance permeable brick and its preparation method provided by the present invention have the following beneficial effects:

1. Iron tailings high-performance permeable brick material is a new type of cement product, which is formed by vibration and pressing, and belongs to the type of non-sintered brick. Iron tailings high-performance permeable bricks are used in public places such as sidewalks, non-motor vehicle lanes, roads with small road loads, parking lots, squares, etc. in the construction of "sponge towns". Permeable leveling layer, 100mm-150mm permeable base, 150mm-200mm permeable subbase, in order to better improve the collection and utilization of permeable water, DN50 PVC seepage pipes are installed in the permeable base, which can effectively divert permeable water into municipal drainage System; the iron tailings high-performance permeable brick has a rough surface and has very good anti-skid properties, which can improve the safety of driving and pedestrians; the permeable brick has a large internal gap, which can alleviate the urban heat island effect and absorb road traffic noise ;

2. The use of iron tailings and fly ash as the basic materials of permeable bricks plays a very good role in promoting "green mine construction", solid waste utilization, and sponge town construction, and can solve the problem of massive accumulation of iron tailings in mines and power plants Environmental protection, safety, operation management and other issues brought by fly ash;

3. The iron tailings are directly used as aggregates in the production line to produce permeable bricks. The aggregate gradation composition cannot meet the requirements of grade A of the permeable grade. According to the aggregate requirements designed for the bottom material of the permeable bricks, machine-made sandstone is used to improve the iron tails. Mine, so that the improved iron tailings mixed aggregate meets the aggregate design grading requirements, greatly improving the permeability of permeable bricks;

4. Iron tailings sand fineness modulus = 1.5, which belongs to ultra-fine sand, and because the iron tailings and fly ash mixed with iron tailings permeable bricks are relatively high, in order to improve the brick forming quality, vibration and static pressure phase are adopted Combined with high-pressure extrusion technology for secondary molding, it realizes the integrated production of iron tailings permeable bricks. It does not require roasting and does not produce any environmental pollution. It can consume iron tailings and fly ash in large quantities and realize the utilization of solid waste resources;

5. The production of iron tailings permeable bricks can be built on the spot around the iron tailings pond, which can reduce the transportation of iron tailings. The raw materials do not need to be sintered, and there is no sintering link in the production process. Iron tailings can also replace aggregates. Compared with traditional permeable bricks, it has better market competitiveness and can realize industrialization promotion by reducing production costs.

The above descriptions are only examples of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the content of the description of the present invention, or directly or indirectly used in other related technical fields, shall be The same reasoning is included in the patent protection scope of the present invention.

Claims (8)

1. The high-performance water permeable brick of the iron tailings is characterized by comprising the following components in parts by weight: 78 to 88 portions of sand-stone modified iron tailings, 10 to 15 portions of cement, 2 to 8 portions of fly ash, 0.3 to 0.8 portion of cement polymer reinforcing agent and 0.20 to 0.30 portion of water-cement ratio.

2. The iron tailing high-performance water permeable brick according to claim 1, characterized by comprising the following components in parts by weight: 83 parts of sandstone modified iron tailings, 11 parts of cement, 5.45 parts of fly ash, 0.55 part of cement polymer reinforcing agent and 0.28 part of water-cement ratio.

3. The preparation method of the iron tailing high-performance water permeable brick is characterized by comprising the following steps:

s1: designing the iron tailing pavement water permeable brick material: considering the economic transport distance of the water permeable bricks, determining the use environment to be a hot-summer and cold-winter area, and preparing the high-strength and high-performance water permeable bricks according to the A-level water permeability requirement to design the materials of the bottom layer and the surface layer of the water permeable bricks;

s2: replacing aggregate with iron tailings and improving: removing impurities from iron tailings, cleaning, making sand, screening and evaluating the particle fineness degree of the iron tailings, and improving by adopting machine-made sand and broken stones according to a constructed permeable brick aggregate grading improvement function model;

s3: mixing the brick bottom materials which permeate water: firstly adding the iron tailing modified aggregate, the cement polymer reinforcing agent and the fly ash into a concrete mixer, stirring for 35-60 s to mix and stir uniformly, adding half of the water consumption in the mixing ratio, stirring for 45-60 s, adding the remaining half of the water consumption when the mixture reaches a uniform and moist state, and stirring for 3-4 min to obtain an iron tailing water permeable brick mixed base material;

s4: mixing the permeable brick surface materials: firstly, adding granite machine-made sand or quartz sand, cement and a cement polymer reinforcing agent into a concrete mixer, stirring for 30-45 s to mix uniformly, adding half of water consumption in the mixing ratio, stirring for 45-50 s, adding the remaining half of water consumption when the mixture reaches a uniform and moist state, and stirring for 2-3 min to obtain the iron tailing water permeable brick mixed fabric;

s5: vibration and pressure molding: transporting the prepared permeable brick mixed bottom material and the prepared fabric to a bottom material bin and a surface material bin respectively through an inclined belt conveyor, putting the iron tailing permeable brick mixed bottom material into a mold for vibration pressure forming, then pressurizing the fabric to a formed brick surface layer, and setting the static pressure to be 18MPa +/-2 MPa for pressure forming to prepare the permeable brick;

s6: and (5) maintenance: and (3) after finishing the process of the iron tailing water permeable brick surface layer, smoothing the surface by using a trowel, conveying the iron tailing water permeable brick surface layer into a maintenance workshop through a track for standard maintenance and outdoor manual maintenance, and after the maintenance age is 28d, delivering the iron tailing water permeable brick surface layer out of the factory after the iron tailing water permeable brick surface layer is inspected to be qualified.

4. The preparation method of the iron tailing high-performance water permeable brick according to claim 3, wherein in the step S1, the design of the materials of the bottom layer and the surface layer of the water permeable brick is carried out according to the technical index requirements that the use environment is a hot-summer and cold-winter area, the water permeability grade A is, the average value of the breaking strength is not lower than 4.0Mpa, the average value of the splitting tensile strength is not lower than 4.0Mpa, the length of a grinding pit is not more than 35mm, and the antiskid BPN value is not less than 60; the permeable brick bottom material consists of iron tailings, machine-made sandstone, fly ash, cement and a cement polymer reinforcing agent, wherein the particle size of the machine-made sandstone modified iron tailings is 0.075 mm-9.5 mm, the ratio of cement to fly ash to cement polymer reinforcing agent = 14; the permeable brick facing material consists of granite machine-made sand, cement and a cement polymer reinforcing agent, wherein the particle size of the granite machine-made sand is 1.18-2.36 mm, the granite machine-made sand in the mixture comprises cement and the cement polymer reinforcing agent = 4.35; the cement is ordinary portland cement, and the strength of the cement is not lower than 42.5; the grade of the fly ash is not lower than grade II.

5. The preparation method of the iron tailing high-performance water permeable brick according to claim 3, wherein in the step S2, the iron tailing replaces the aggregate and is modified, the iron tailing is firstly subjected to impurity removal, cleaning and screening through a water elutriation screening machine, stone powder and iron tailing sand are separated, the fineness modulus of the iron tailing sand is evaluated to be =1.5 through a screening test, machine-made sand and broken stones are adopted to modify the iron tailing in an intermittent grading mode according to the aggregate grading design of the water permeable brick, the proportion of the particle size of the modified mixture of 0.075mm to 4.75mm to the total aggregate is 10% -15%, and the aggregate grading modification function model of the water permeable brick is as follows:

y＝Ax ^B wherein x is more than or equal to 4.75 and less than or equal to 9.5;

y =0.43x+1, wherein x is more than 1.18 and less than 4.75;

y =0.53x +1, wherein x is more than 0.30 and less than or equal to 1.18;

y = Clnx + D, wherein x is not less than 0.075 and not more than 0.30;

in the formula: x represents the aggregate particle diameter, y represents the sieving pass rate, and A, B, C, and D are regression coefficients.

6. The preparation method of the iron tailing high-performance water permeable brick according to claim 3, wherein the mixing of the bottom materials of the water permeable brick in the step S3 and the mixing of the surface materials of the water permeable brick in the step S4 are performed by adopting separate and parallel stirring systems, and the mixing and stirring time of the bottom materials is 30-60S earlier than that of the surface materials.

7. The preparation method of the iron tailing high-performance water permeable brick according to claim 3, wherein in the step S5, vibration and compression molding is carried out, the set static pressure is 18MPa, the vibration and compression molding time is controlled to be 20S-25S, and the color of the fabric is colored and sprayed according to actual needs.

8. The method for preparing the iron tailing high-performance water permeable brick according to claim 3, wherein in the step S6, the maintenance comprises standard maintenance and natural maintenance in a maintenance workshop, the water permeable brick is stacked after being fed into the maintenance workshop with the temperature of 20 ℃ plus or minus 2 ℃ and the humidity of not less than 95% through a rail for maintenance for 24 hours, the artificial maintenance is continued in an outdoor environment, the water is watered for 2 times every day until the maintenance is carried out for 28 days at a specified age, and the iron tailing high-performance water permeable brick is delivered after being inspected.