CN1197807C - Technique for producing non-extrusion clayless solid slag sintering brick - Google Patents

Abstract

A production method of extrusion-free clay-free solid waste slag sintered bricks, the main raw material of which is industrial solid waste slag including fly ash, tailings, phosphorus slag, waste sand, slag, red mud, sulfuric acid slag, sludge, and phosphoric acid Additives of two different systems based on water glass or water glass are prepared according to the proportion of silicon, aluminum, iron and calcium oxide contained in the main raw materials, and are obtained through mixing, pouring, curing, drying, sintering and other processes. The present invention does not use clay, cement, lime and other raw materials as binders, and adopts pouring and vibration molding methods for forming, so the comprehensive utilization rate of waste is improved, the usage of natural resources is reduced, and production investment, power consumption, coal consumption and Cost of production. Product performance can be compared with ordinary clay fired bricks. It is a very promising building wall material.

Description

A production method of extrusion-free and clay-free solid waste sintered brick

1. Technical field: building materials

2. Background technology:

As a typical representative of "Qin bricks and Han tiles", clay fired bricks have been used in my country for thousands of years and are still widely used today. The so-called clay brick is the most widely used building wall material, which is formed by clay as raw material and sintered at high temperature. The production and use of clay brick not only damages the environment, reduces cultivated land, but also wastes resources and energy. It is prohibited by the state and Outdated products with limited use. In order to replace clay bricks and make use of industrial waste, the technology of using industrial waste to manufacture new wall materials was developed in my country in the 1960s, and three representative technologies of sintering, autoclaving, and non-steaming and non-burning have been formed. . Among them, fly ash sintered bricks and coal gangue sintered bricks are representatives of sintering methods. The so-called fly ash sintered brick is a building wall material made of fly ash and clay as the main raw materials through the processes of raw material aging, batching, mixing, extrusion molding, drying and roasting. Sintered fly ash bricks have a history of more than 40 years in our country. At first, the plastic extrusion process was adopted, and the content of fly ash was generally about 25%. The hard plastic extrusion process is adopted to increase the fly ash content to 45%. In order to further increase the amount of fly ash, some units have adopted the method of pressing and molding to increase the amount of fly ash to more than 70%. Using a small amount of inorganic or organic binders without clay, increasing the amount of fly ash, and producing all-fly ash sintered bricks will be a way out for brick-making enterprises that use fly ash as raw material.

There are two traditional fly ash sintered brick molding processes: extrusion molding and semi-dry pressing molding. Since fly ash is a barren material with poor plasticity, the extrusion molding process requires the mixture to have good plasticity and make the green body have a certain strength, which requires measures to be taken from the plasticity and proportion of the extruder and clay . If the amount of fly ash added is too high, plastic extrusion is difficult, the quality of the green body is poor, and the wear and tear on the equipment is large; if forced extrusion is required to increase the amount of fly ash added, high power, high vacuum and external Adhesive solution, which will undoubtedly increase investment and increase costs. Practice has proved that when the amount of fly ash is 60%, the sintered brick produced by extrusion process has a high reject rate and the cost is higher than that of low-amount fly ash. The semi-dry pressing molding method must also use clay as a binder, but due to the different molding methods, the amount of fly ash can be increased, but the increase is limited. The reason is: fly ash is generally very fine, and the particle size Evenly mixed, when pressing and forming, the phenomenon of green body spalling is very common. In order to overcome this technical problem, an appropriate amount of coarse aggregate (such as furnace bottom slag, quartz sand, slag) must be added. Too little coarse aggregate will not play a role ; Too much aggregate reduces the proportion of fly ash and affects product performance. Therefore, it can be seen from the principle analysis that it is impossible to produce all-fly ash sintered bricks with traditional molding methods.

In recent years, many units and individuals have carried out developments in increasing the amount of fly ash and improving the formula of firing bricks, and have made progress one after another, and disclosed some patented technologies:

Chinese patent 1049148 (publication number) discloses a new formula of fly ash sintered brick, formula is: fly ash 30～80%, expansive soil 20～50%, coal gangue 10～30%, borax 1～5%; 1121920 (publication number) discloses a kind of clay-free fly ash sintered brick and its preparation method, formula is: fly ash 80～97%, calcareous bentonite 3～20%; The production process of ash sintered bricks uses fly ash, expanded perlite, bentonite, and clay as raw materials. 128705 (publication number) discloses a high-volume fly ash sintered brick and its production method, its formula is: fly ash 70～90%, soil 30～10%, basic sodium phosphate 0.5～1.5%, chloride Ammonium 0.1～0.8%; CN1325831A discloses a kind of production technology of fly ash sintered brick, its formula is fly ash 80～90%, clay 17～4%, flux 3～6%, wherein flux consists of alkali, Broken glass and hydromica are composed of 5/2/3; CN1091404A discloses a method for manufacturing colored glazed tiles and corrugated tiles with copper smelting slag, and its notable feature is to use high-speed iron waste slag that will be roasted first, and use phosphoric acid or phosphoric acid di Aluminum hydrogen is the binding agent; CN1358583A discloses a method for building materials with cullet as the main raw material, and its formulation features are: glass/auxiliary/fly ash/water glass=100/2～4/200～400 /20～40, the additives are complexes of borax, sodium carbonate, antimony, graphite, etc.

As far as sintered bricks are concerned, the production of sintered bricks with fly ash and coal gangue as the main raw materials is the most representative, but from the current technology, it is not difficult to find the following characteristics:

(1) Molding method: Whether it is traditional technology or open patented technology, there are only two green molding methods of sintered bricks: extrusion and pressing;

(2) Formulation: The traditional technology mainly uses clay as the binder; the clay-free type uses bentonite as the binder; in some formulations, fluxes such as borax and sodium phosphate are used.

Taking a broad view of the traditional technologies, no clay (including no bentonite), no extrusion molding, so that the mass ratio of fly ash in the brick is greater than 90% of the technology has not been reported.

3. Contents of the invention

1, the purpose of the present invention

Making sintered bricks from industrial waste is still one of the main technical routes for large-scale utilization of waste. Therefore, the object of the present invention is: to solve the problems that traditional waste slag sintered bricks must use clay, high-pressure molding, low fly ash content and high cost, to invent a method that can greatly improve the quality of fly ash without clay and extrusion. A brick-making technology that reduces the amount of industrial waste slag and reduces production investment and production costs. The invention will have positive significance for large-scale utilization of industrial waste residues, environmental protection and natural resource saving.

2. Technical content of the present invention

1) raw material of the present invention:

(1) Main raw materials: industrial waste, including fly ash, tailings, phosphorus slag, waste sand, slag, red mud, sulfuric acid slag, sludge, which can be used alone or mixed and matched with two or more use;

(2) Additives: It consists of two systems. System 1 is made of phosphoric acid or aluminum dihydrogen phosphate as the main material, and sodium silicate, sodium carbonate, sodium fluoride, borax, sodium fluorosilicate, cellulose, and waste glass are used together; System 2 uses water glass as the main material, combined with sodium silicate, sodium carbonate, caustic soda, sodium fluoride, borax, sodium fluorosilicate, cellulose, and waste glass;

(3) Mixing ratio of raw materials:

The mixing ratio range of main raw materials and additives is shown in the table below. Formula system main raw material Additive composition (mass ratio of the main raw material%) phosphoric acid water glass Sodium silicate Sodium carbonate caustic soda sodium fluoride Borax Sodium fluorosilicate Cellulose waste glass System 1(%) 100 1.5～9 0.2～5 0～2 0～3 0～3 0.3～3 0～5 0～3 0～5 System 2(%) 100 3～9 0～4 0～3 0～2 0.2～1.5 0～0.9 0.3～1.0 0～3 0～5

(4) Scope of application of the formula

The main raw material industrial waste slag used in the present invention includes fly ash, tailings, phosphorus slag, waste sand, slag, red mud, sulfuric acid slag, and sludge, which can be used alone or in combination of two or more . When the sum of the mass percentages of silicon oxide and aluminum oxide in the main raw material is greater than 75%, or the sum of silicon oxide and iron oxide is greater than 70%, the two additive systems in the table can be used; when the main raw material is silicon oxide, aluminum oxide, oxide Additive system 2 is used when the sum of iron mass percentages is less than 50% and calcium oxide is greater than 10%.

The phosphoric acid used in system 1 in the table can be used alone, or can be combined with aluminum dihydrogen phosphate in a weight ratio of 1/0.1-1 by mass.

2) Process:

(1) If the solid waste slag as the main raw material is in large pieces or large particles, it needs to be crushed first. If only one kind of waste slag is used alone, it needs to be ground. If more than one kind of waste residues are used in combination, the maximum size of the waste residue particles of the main raw material is required to be less than 3mm, and the maximum particle size of at least one of the waste residues is required to be less than 0.1mm. The different types and sizes of waste residues used need to be mixed evenly;

(2) Substances in the additives that can be dissolved in water, after metering and mixing, are dissolved in water equivalent to 8-35% of the dry mass of the main raw materials; additives that cannot be dissolved in water, such as waste glass, need to be ground to make the particles the largest less than 0.1mm, and then mixed evenly with the solid waste residue as the main raw material.

(3) Mix the treated main raw materials and the aqueous solution of additives evenly, and wet mix for more than 5 to 15 minutes;

(4) Pouring the uniformly stirred mixture into a mold with stable dimensions (steel mold, wood mold, plastic mold can be used), vibration molding; demoulding after natural curing for 3 to 24 hours;

(5) Place the green body on a movable flat plate and send it into the drying room. The temperature of the drying room is 40-200°C. The heat source can be steam, electricity, coal, or heavy oil; It is best to contain carbon dioxide with a volume percentage greater than 0.5%, and the temperature is not higher than 200°C; the drying room needs to be equipped with an induced draft fan for dehumidification; when the moisture content of the green body is less than 5%, the drying process ends;

(6) The dried green body is first put into a tunnel kiln or a wheel kiln for roasting after stacking. The highest temperature is 900-1150°C, and it is kept at the highest temperature for 1-5 hours, and then slowly cooled with the furnace to become a product; The residual heat from the cooling process is used for green body drying.

3. The advantages of this technology compared with the prior art

The significant difference between the present invention and traditional brick-making technology is:

1) The present invention does not use clay, lime, cement, shale, bentonite as binding agent at all;

2) The present invention adopts pouring and vibration forming, without extruder and press machine.

3) The properties of the sintered bricks prepared by the present invention vary due to the properties of the main raw materials used and the series of additives selected, but the main properties can all reach the quality index of MU10 ordinary clay bricks, wherein the compressive strength is greater than 10Mpa, and the flexural strength is greater than 10Mpa. The strength is greater than 2.7Mpa, the density is less than 1.4g/cm ³ , and the water absorption rate is less than 23%; the size is regular, the appearance is neat, and it is brick red

It is the difference in raw material formula and molding method that makes the present invention have great advantages compared with the traditional technology: it improves the comprehensive utilization rate of waste and reduces the use of natural resources; it significantly saves investment, especially reduces electricity consumption. consumption and coal consumption, reducing the cost.

Four, description of drawings: Fig. 1 is the technological process of figure of the present invention:

5. Embodiment

Embodiment 1: get 1000 mass parts of fly ash with calcium oxide mass percentage content less than 8%, 43 mass parts of additives, wherein the composition of additives is: phosphoric acid 15 mass parts, borax 5 mass parts, sodium silicate 20 mass parts, 3 parts by mass of cellulose, 350 parts by mass of water; the dry material is firstly mixed evenly, the additive is dissolved in water, wet mixed evenly and then poured into molding, demolded after 12 hours, dried at 100°C for 2 hours, and the green body is sent into the furnace Slowly raise the temperature for sintering, and keep it warm at 1050°C for 1 hour, then cool with the furnace, and release it after cooling down to below 80°C. The brick has a density of 1.3g/cm ³ , a compressive strength of 22Mpa, and a flexural strength of 5Mpa. It can be refired 5 times without deformation or crack.

Embodiment 2: get 1000 mass parts of fly ash with calcium oxide mass percentage content less than 8%, 91 mass parts of additives, wherein additives consist of: 35 mass parts of water glass, 9 mass parts of borax, 10 mass parts of sodium silicate, 3 parts by mass of cellulose, 4 parts by mass of sodium fluorosilicate, 30 parts by mass of glass powder, the glass powder in the additive is mixed with fly ash first, and the remaining materials are dissolved in 340 parts by mass of water; the dry material and the aqueous solution of the additive are mixed evenly before pouring Forming, demoulding after 5 hours, drying at 100°C for 2 hours, sending the green body into the furnace for slow heating and sintering, and keeping it at 1080°C for 1 hour, cooling with the furnace, and releasing the furnace after cooling down to below 80°C. The brick has a density of 1.4g/cm ³ , a compressive strength of 15Mpa, a flexural strength of 4Mpa, a brick red color, and a linear shrinkage rate of 3.0%.

Embodiment 3: Take 980 mass parts of water glass waste sand produced in the foundry, and grind until the maximum particle size is less than 1mm; 20 mass parts of phosphorus slag, grind until the maximum particle size is less than 0.1mm; become the main raw material after mixing evenly, additives 89 parts by mass, wherein the composition of the additives is: 80 parts by mass of phosphoric acid, 9 parts by mass of borax, and 340 parts by mass of water; the main ingredients are mixed uniformly first, the additives are dissolved in water, and the two types of materials are wet-mixed evenly and then poured into molding, and removed after 5 hours. Die, dry at 100°C for 2 hours, send the green body into the furnace for slow heating and sintering, and keep it at 1150°C for 1 hour, cool with the furnace, and release it after cooling down to below 80°C. The brick has a density of 0.9g/cm ³ , a compressive strength of 11Mpa, a flexural strength of 2.9Mpa, is white, and has almost zero linear shrinkage.

Embodiment 4: Take 1000 mass parts of undisturbed copper slag (particle size is less than 3mm), 400 mass parts of yellow phosphorus slag, grind to maximum particle size and be less than 0.1mm; Waste glass powder 70 mass parts, grind to maximum particle size and be less than 0.1mm mm; the three raw materials are mixed uniformly to become the main raw material, and the additive is 46 parts by mass, wherein the additive is composed of: 40 parts of water glass, 6 parts of sodium fluorosilicate, and 160 parts of water; the main material is mixed uniformly first, the additive is dissolved in water, and the additive The medium sodium fluorosilicate is first ground until the particle size is less than 0.05mm, and then dry-mixed with the main material; the main material and the additive are wet-mixed evenly, and then casted, demolded after 3 hours, dried at 100 ° C for 2 hours, and The green body is sent into the furnace for slow heating and sintering, and is kept at 1100°C for 1 hour, then cooled with the furnace, and released after the temperature is lower than 80°C. The density of this brick is 2.4g/cm3, the compressive strength is greater than 50Mpa, the flexural strength is 30Mpa, and the shrinkage rate is almost zero.

Claims (3)

1, a kind of production method of non-extrusion clayless solid slag sintering brick is characterized in that:

1) technical process: main raw material and additive are behind levigate, prescription, mixing, be cast in the mould, get base substrate through vibratory compaction, spontaneous curing, base substrate is sent into kiln and is dehydrated after the demoulding, in sintering oven, carry out sintering behind the sign indicating number base, and under top temperature, be incubated, obtain the finished product vitrified brick after the cooling at a slow speed subsequently;

2) raw material and prescription

(1) main raw material: industrial residue, comprise flyash, mine tailing, phosphorus slag, antiquated sand, slag red mud, sulfate slag, mud, they both can use separately, but also two or more mix and match uses;

(2) additive: be divided into based on the system 1 of phosphoric acid with based on the system 2 of water glass, be equipped with water glass, yellow soda ash, Sodium Fluoride, Sodium Silicofluoride, borax, Mierocrystalline cellulose, caustic soda, cullet again;

(3) quality proportioning: main raw material 100%, additive system 1 accounts for the mass percent of main raw material: phosphatase 11 .5～9, water glass 0.2～5, yellow soda ash 0～2, caustic soda 0～3, Sodium Fluoride 0～3, Sodium Silicofluoride 0～5, borax 0.3～3, Mierocrystalline cellulose 0～3, cullet 0～5; Additive system 2 accounts for the mass percent of main raw material: water glass 3～9, water glass 0～4, yellow soda ash 0～3, caustic soda 0～2, Sodium Fluoride 0.2～1.5, Sodium Silicofluoride 0.3～1.0, borax 0～0.9, Mierocrystalline cellulose 0～3, cullet 0～5, silicon oxide and aluminum oxide quality percentage ratio sum are greater than 75% in main raw material, and perhaps silicon oxide and ferriferous oxide mass percent sum adopted above-mentioned two kinds of additive systems greater than 70% o'clock; Silicon oxide, aluminum oxide, ferric oxide mass percent sum are less than 50% in main raw material, and the calcium oxide mass percent adopted additive system 2 greater than 10% o'clock;

3) technical qualification

(1) granularity of main raw material: if be bulk or macrobead, at first need fragmentation as the solid slag of main raw material, if having only a kind of waste residue to use separately, then require grinding, the particle maximum diameter is less than 0.5mm, natural grading; If two or more waste residue is used, the waste particle overall dimension that then requires main raw material is less than 3mm, and the particle overall dimension that requires at least a waste residue wherein is less than 0.1mm;

(2) water-fast material such as cullet need be levigate in the additive, and make particle overall dimension less than 0.1mm, and mix with main raw material; Water-soluble material water dissolution that is equivalent to main raw material dry state quality 8～35%;

(3) main raw material and additive and aqueous solution thereof are even, and the wet mixing time is 5～15 minutes;

(4) wet mixed feed cast and vibratory compaction, spontaneous curing 3～24 hours;

(5) the kiln temperature is 40～200 ℃, is dried to the green body quality water ratio less than 5%;

(6) maturing temperature is 900～1150 ℃, and is incubated 1～5 hour under top temperature.

2, the production method of non-extrusion clayless solid slag sintering brick according to claim 1 is characterized in that: additive system 1 used phosphoric acid can use separately, also can be 1/0.1～1 part by weight collocation with aluminium dihydrogen phosphate by mass ratio.

3, the production method of non-extrusion clayless solid slag sintering brick according to claim 1 is characterized in that: when dry, contain percent by volume in the dry gas greater than 0.5% carbon dioxide.