Electrolytic manganese residue-red mud concrete material, preparation method and application thereof

Abstract

The present application belongs to the technical field of concrete materials, and particularly relates to an electrolytic manganese residue-red mud concrete material, a preparation method and application thereof. The raw material components of the electrolytic manganese residue-red mud concrete material include electrolytic manganese residue-red mud modified micro powder, an adjusting agent, fine aggregate and coarse aggregate. The raw material components of the electrolytic manganese residue-red mud modified micro powder include electrolytic manganese residue, red mud, quicklime, ammonia nitrogen curing agent and heavy metal ion stabilizer. The sulfate radical in the electrolytic manganese residue and the alkali in the red mud can be combined with the adjusting agent to generate alkali-complex salt excitation, accelerate the hydration rate and reaction degree of the material, improve the strength of the cementitious material, and generate hydration products of ettringite and zeolite-like, which can block the pores of the concrete to improve the compactness. In combination with the fine aggregate and coarse aggregate, the bending tensile strength and wear resistance of the concrete are improved. In addition, the harmless treatment of the electrolytic manganese residue and the red mud is realized through the modification treatment, and the pollution of the concrete material to the environment is reduced.

Description

Technical Field

[0001] This invention belongs to the field of concrete materials technology, and specifically relates to an electrolytic manganese slag-red mud concrete material, its preparation method, and its application. Background Technology

[0002] Electrolytic manganese slag is a type of industrial waste obtained by leaching manganese ore with sulfuric acid solution after fine grinding. Electrolytic manganese slag is acidic, contains sulfates and other chemical substances, and contains certain amounts of hexavalent chromium, mercury, vanadium, and other heavy metals, which limits its application in building materials. Furthermore, the harmful substances ammonia nitrogen and manganese in electrolytic manganese slag exist in the form of soluble sulfates. As an aggregate for concrete, electrolytic manganese slag exhibits instability factors such as excessively low strength and excessive volume change rate.

[0003] Red mud is a highly alkaline industrial solid waste generated during the production of alumina from gibbsite. It has a high alkali content, and when stored and treated, alkali and metal ions will overflow, polluting the environment. Moreover, the huge amount of red mud discharged and the disposal methods of the stockpiles put enormous pressure on land resources and the natural environment.

[0004] Electrolytic manganese slag and red mud, as two types of industrial waste, pose significant environmental risks if directly stockpiled and discharged due to their diverse components. Currently, the comprehensive utilization of electrolytic manganese slag and red mud faces several technical challenges. For example, red mud has a high alkali content; during stockpiling, alkali and metal ions can leach out, polluting surface water. Furthermore, red mud particles are fine and highly viscous when wet, hindering construction. Electrolytic manganese slag contains manganese ions and ammonia nitrogen; long-term stockpiling is detrimental to the environment. When used as aggregate, electrolytic manganese slag exhibits poor mechanical properties and stability, posing a risk of environmental pollution when used as filler. Additionally, when applied to concrete, the various components in the electrolytic manganese slag make direct application difficult, requiring treatment to overcome its adverse effects on concrete performance. Moreover, directly incorporating electrolytic manganese slag and red mud into concrete can lead to decreased concrete strength, poor volume stability, and the resulting concrete poses a risk of environmental pollution.

[0005] Therefore, there is an urgent need to provide a concrete material that can absorb and utilize large quantities of electrolytic manganese slag and red mud, and has good flexural strength and wear resistance. This material can achieve harmless treatment and good resource reuse of electrolytic manganese slag and red mud without increasing the cost of concrete construction. Summary of the Invention

[0006] This invention aims to solve one or more technical problems existing in the prior art, and at least provide a beneficial option or create conditions. This invention provides an electrolytic manganese slag-red mud concrete material, which has good flexural strength and wear resistance. Without increasing concrete construction costs, it can utilize large quantities of manganese slag and red mud, achieving harmless treatment and effective resource reuse of electrolytic manganese slag and red mud.

[0007] The inventive concept of this invention is as follows: This invention utilizes the slightly alkaline properties of red mud. On one hand, it can neutralize the acid in electrolytic manganese slag and facilitate the removal of ammonia nitrogen and precipitated manganese ions, reducing the risk of environmental pollution. On the other hand, the alkali in the red mud reacts with the sulfate ions in the electrolytic manganese slag, triggering an alkali-double salt reaction with a modifier. This accelerates the hydration rate and reaction degree of the materials, improving the strength of the cementitious materials. The resulting hydrated alum and zeolite-like hydration products can also seal the pores of the concrete, increasing its density. Furthermore, combined with fine and coarse aggregates, it improves the flexural strength and wear resistance of the concrete. In addition, this invention modifies the electrolytic manganese slag and red mud using quicklime, ammonia nitrogen curing agents, and heavy metal ion stabilizers, achieving the harmless treatment of these materials and reducing the environmental pollution caused by concrete materials during use.

[0008] Therefore, a first aspect of the present invention provides an electrolytic manganese slag-red mud concrete material.

[0009] Specifically, the raw material components of the electrolytic manganese slag and red mud concrete material include electrolytic manganese slag-red mud modified micro powder, modifier, fine aggregate, and coarse aggregate;

[0010] The raw material components of the modified electrolytic manganese slag-red mud powder include electrolytic manganese slag, red mud, quicklime, ammonia nitrogen curing agent, and heavy metal ion stabilizer.

[0011] Specifically, the concrete refers to an engineering composite material in which aggregates such as sand and stone are bound together into a whole by cementing materials. These cementing materials, under physical and chemical action, can transform from a paste into a solid, stone-like substance and can bind other materials to form a composite solid with a certain mechanical strength.

[0012] Specifically, the residual heat and alkalinity of red mud are utilized, and quicklime is added to provide a calcium source, accelerating the deammoniation and desulfurization treatment of electrolytic manganese slag; ammonia nitrogen solidifying agents and heavy metal ion stabilizers are used to stabilize heavy metal ions and ammonia nitrogen in the manganese slag, reducing hazards; and the OH groups in the red mud are utilized to further enhance the desulfurization process. - It reacts with manganese ions in electrolytic manganese slag to form a precipitate, and reacts with ammonia nitrogen (NH3-N) in electrolytic manganese slag to form ammonia gas, thereby removing manganese ions and ammonia nitrogen from electrolytic manganese slag, thus modifying electrolytic manganese slag and red mud, and ultimately achieving the harmless treatment of electrolytic manganese slag and red mud.

[0013] Preferably, by weight, the raw material components of the electrolytic manganese slag-red mud concrete material include 7-11 parts of modified electrolytic manganese slag-red mud powder, 9-13 parts of modifier, 13-27 parts of fine aggregate, and 35-60 parts of coarse aggregate.

[0014] More preferably, by weight, the raw material components of the electrolytic manganese slag-red mud concrete material include 8-10 parts of modified electrolytic manganese slag-red mud micro powder, 10-12 parts of modifier, 15-25 parts of fine aggregate, and 40-55 parts of coarse aggregate.

[0015] Preferably, the raw material components of the electrolytic manganese slag-red mud concrete material further include a water-reducing agent and at least one of the following in water:

[0016] More preferably, the raw material components of the electrolytic manganese slag-red mud concrete material also include water-reducing agent and water.

[0017] Preferably, by weight, the raw material components of the electrolytic manganese slag-red mud concrete material include 7-11 parts of modified electrolytic manganese slag-red mud powder, 9-13 parts of modifier, 13-27 parts of fine aggregate, 35-60 parts of coarse aggregate, 0.9-2.2 parts of water-reducing agent, and 5.5-10 parts of water.

[0018] More preferably, by weight, the raw material components of the electrolytic manganese slag and red mud concrete material include 8-10 parts of modified micro powder of electrolytic manganese slag-red mud, 10-12 parts of modifier, 15-25 parts of fine aggregate, 40-55 parts of coarse aggregate, 1-2 parts of water-reducing agent, and 6-9 parts of water.

[0019] Preferably, the modifier includes at least one of steel slag, fly ash, blast furnace slag, waste incinerator slag, and non-ferrous metallurgical slag.

[0020] Preferably, the fine aggregate is selected from at least one of stone powder and river sand.

[0021] Preferably, the fine aggregate has a particle size of less than 4.75 mm.

[0022] Preferably, the coarse aggregate is selected from at least one of rock particles, pebbles, mine tailings, and industrial waste.

[0023] More preferably, the coarse aggregate is rock particles.

[0024] Specifically, the coarse aggregate is prepared from rocks, pebbles, mine tailings or industrial waste through processes such as soil removal, mechanical crushing, shaping, screening and powder control.

[0025] Preferably, the mass content of mud lumps in the coarse aggregate is less than or equal to 1%, and more preferably, the mass content of mud lumps is less than or equal to 0.2%.

[0026] Preferably, the coarse aggregate has a particle size greater than 4.75 mm.

[0027] Preferably, the coarse aggregate is a mixture of three particle sizes: greater than or equal to 5 mm and less than or equal to 10 mm, greater than 10 mm and less than 20 mm, and greater than or equal to 20 mm and less than or equal to 31.5 mm.

[0028] Preferably, the mass content of needle-shaped and flaky particles in the coarse aggregate is less than or equal to 9%; more preferably, the mass content of needle-shaped and flaky particles in the coarse aggregate is less than or equal to 8%.

[0029] Preferably, the water-reducing agent is a polycarboxylate superplasticizer.

[0030] Preferably, the water-reducing agent has a mass fraction of 0.8-1.2%; more preferably, the water-reducing agent has a mass fraction of 0.9-1.1%; and even more preferably, the water-reducing agent has a mass fraction of 1%.

[0031] Preferably, the water-reducing agent has a water reduction rate of greater than 25%.

[0032] Preferably, the electrolytic manganese slag comprises, by mass percentage, 8.0-11% CaO, 30-38% SiO2, 4.5-7% Al2O3, 16-24% Fe2O3, 7.0-9% MnO, and 17-25% SO3.

[0033] More preferably, the electrolytic manganese slag comprises, by mass percentage, 8.5-10% CaO, 33-35% SiO2, 5-6.5% Al2O3, 18-22% Fe2O3, 7.5-8% MnO, and 19-23% SO3.

[0034] Preferably, the red mud is selected from red mud obtained from iron ore beneficiation in Guangxi; the mass fraction of calcium, aluminum and silicon components in the red mud is greater than 35%.

[0035] Preferably, the red mud is Bayer process red mud.

[0036] Preferably, the red mud comprises, by mass percentage, 16-23% alumina, 14-23% calcium oxide, 10-18% silicon dioxide, 30-40% iron oxide, and 4-12% sodium oxide.

[0037] More preferably, by mass percentage, the red mud comprises 17-22% alumina, 14-21% calcium oxide, 10-16% silicon dioxide, 30-38% iron oxide, and 4-11% sodium oxide.

[0038] Preferably, by weight percentage, the raw material composition of the modified micro-powder of electrolytic manganese slag-red mud includes 30-47% electrolytic manganese slag, 35-55% red mud, 6.5-10% quicklime, 4.0-6.5% ammonia nitrogen curing agent, and 1.6-2.4% heavy metal ion stabilizer.

[0039] More preferably, by weight percentage, the raw material composition of the modified electrolytic manganese slag-red mud powder includes 33-43% electrolytic manganese slag, 40-50% red mud, 7-9% quicklime, 4.5-6% ammonia nitrogen curing agent, and 1.8-2.2% heavy metal ion stabilizer.

[0040] Preferably, the raw material components of the electrolytic manganese slag-red mud modified micro powder further include at least one of a dispersant and a grinding aid.

[0041] More preferably, the raw material components of the electrolytic manganese slag-red mud modified micro powder also include dispersants and grinding aids.

[0042] Preferably, by mass percentage, the raw material composition of the modified electrolytic manganese slag-red mud powder includes 30-47% electrolytic manganese slag, 35-55% red mud, 6.5-10% quicklime, 4.0-6.5% ammonia nitrogen curing agent, 1.6-2.4% heavy metal ion stabilizer, 1.6-2.4% dispersant, and 0.8-1.2% grinding aid.

[0043] More preferably, by mass percentage, the raw material composition of the modified electrolytic manganese slag-red mud powder includes 33-43% electrolytic manganese slag, 40-50% red mud, 7-9% quicklime, 4.5-6% ammonia nitrogen curing agent, 1.8-2.2% heavy metal ion stabilizer, 1.8-2.2% dispersant, and 0.9-1.1% grinding aid.

[0044] More preferably, by mass percentage, the raw material composition of the modified electrolytic manganese slag-red mud powder includes 36% electrolytic manganese slag, 46% red mud, 8% quicklime, 5% ammonia nitrogen curing agent, 2% heavy metal ion stabilizer, 2% dispersant, and 1% grinding aid.

[0045] Preferably, the heavy metal ion stabilizer includes at least one of aluminum hydroxide, iron hydroxide, polyaluminum sulfate, layered double hydroxides (LDHs), calcined layered double hydroxides (CLDHs), organic chelating agents, disodium hydrogen phosphate, superphosphate, and lignin-based triaminotriethylamine salts.

[0046] Preferably, the organic chelating agent is a dithiocarbamate (DTC) type organic chelating agent.

[0047] Preferably, the ammonia nitrogen curing agent includes at least one of Na3PO4, NaH2PO4, MgSO4 or their hydrates, superphosphate, phosphogypsum leachate, phosphogypsum, and MgO.

[0048] Preferably, the hydrates of Na3PO4, NaH2PO4, and MgSO4 are Na3PO4·12H2O, NaH2PO4·12H2O, and MgSO4·7H2O, respectively.

[0049] Preferably, the MgSO4·7H2O comprises low-grade MgSO4·7H2O.

[0050] Preferably, the MgO can be replaced with low-grade MgO.

[0051] Preferably, the dispersant comprises at least one of sodium tripolyphosphate, sodium hexametaphosphate, sodium pyrophosphate, triethylhexylphosphate, sodium dodecyl sulfate, methylpentanol, cellulose derivatives, polyacrylamide, carboxylates, polycarboxylates, and sulfonates.

[0052] Preferably, the grinding aid comprises at least one of triethanolamine, fly ash, industrial salt, triisopropanolamine, ethylene glycol, propylene glycol, glycerol, sodium fatty acid, calcium chloride, sodium chloride, sodium acetate, aluminum sulfate, calcium formate, calcium lignosulfonate, and sodium lignosulfonate.

[0053] A second aspect of the present invention provides a method for preparing the electrolytic manganese slag-red mud concrete material described in the first aspect of the present invention.

[0054] Specifically, the preparation method of the electrolytic manganese slag-red mud concrete material includes the following steps:

[0055] The raw material components are mixed and reacted to obtain the electrolytic manganese slag-red mud concrete material.

[0056] Preferably, the preparation method of the electrolytic manganese slag-red mud concrete material includes the following steps:

[0057] First, the modified micro powder of electrolytic manganese slag-red mud, the modifier, the fine aggregate, the water-reducing agent and water are mixed evenly. Then, the coarse aggregate is added and stirred to obtain the electrolytic manganese slag-red mud concrete material.

[0058] Preferably, the stirring time is 2-6 minutes; more preferably, the stirring time is 3-5 minutes.

[0059] Preferably, the preparation method of the modified electrolytic manganese slag-red mud micropowder includes the following steps:

[0060] The raw material components of the modified electrolytic manganese slag-red mud powder are mixed to obtain the modified electrolytic manganese slag-red mud powder.

[0061] More preferably, the preparation method of the modified electrolytic manganese slag-red mud powder includes the following steps:

[0062] First, electrolytic manganese slag, red mud, quicklime, ammonia nitrogen curing agent, heavy metal ion stabilizer, and dispersant are mixed and reacted. Then, grinding aid is added, and the mixture is ball-milled to obtain the modified micro powder of electrolytic manganese slag-red mud.

[0063] Preferably, the mixing is carried out by using a mixer to mix the ingredients evenly.

[0064] Preferably, the stirring time is 8-12 minutes; more preferably, the stirring time is 10 minutes.

[0065] Preferably, the reaction time is 7-13 hours; more preferably, the reaction time is 8-12 hours.

[0066] Preferably, the reaction further includes a drying and crushing process.

[0067] Preferably, after crushing, a grinding aid is added for ball milling.

[0068] Preferably, a planetary ball mill is used for the ball milling.

[0069] Preferably, the ball milling speed is 180-450 r / min, and the ball milling time is 35-65 min.

[0070] More preferably, the ball milling speed is 200-400 r / min, and the ball milling time is 40-60 min.

[0071] Preferably, the ball milling includes forward ball milling and reverse ball milling.

[0072] Preferably, the forward ball milling time is 18-33 minutes, and the reverse ball milling time is 18-33 minutes.

[0073] More preferably, the forward ball milling time is 20-30 minutes, and the reverse ball milling time is 20-30 minutes.

[0074] A third aspect of the present invention provides an application of the electrolytic manganese slag-red mud concrete material described in the first aspect of the present invention in the field of construction.

[0075] Preferably, the construction field includes road construction.

[0076] Compared with the prior art, the beneficial effects of the technical solution provided by the present invention are as follows:

[0077] (1) This invention utilizes the slightly alkaline properties of red mud to neutralize the acid in electrolytic manganese slag and facilitate the removal of ammonia nitrogen and precipitation of manganese ions from the manganese slag, thereby reducing the risk of environmental pollution. On the other hand, the alkali in red mud and the sulfate in electrolytic manganese slag can react with active materials such as slag and fly ash to induce alkali-double salt activation, thereby accelerating the hydration rate and reaction degree of the materials and improving the strength of the cementitious materials. The hydration products of ettringite and zeolite generated by the modified micro powder, modifier, and active materials of electrolytic manganese slag-red mud can also seal the pores of concrete, improve the density, and, combined with fine and coarse aggregates, improve the flexural strength and wear resistance of concrete.

[0078] (2) This invention utilizes the alkalinity of red mud, adding quicklime to provide a calcium source, accelerating the deammoniation and desulfurization treatment of electrolytic manganese slag, and using ammonia nitrogen solidifying agents and heavy metal ion stabilizers to stabilize heavy metal ions and ammonia nitrogen in electrolytic manganese slag, reducing hazards; and through the OH- of red mud... - It reacts with manganese ions in electrolytic manganese slag to form a precipitate, and reacts with ammonia nitrogen (NH3-N) in electrolytic manganese slag to generate ammonia gas, thereby removing manganese ions and ammonia nitrogen from electrolytic manganese slag and achieving the harmless treatment of manganese slag and red mud.

[0079] (3) Without increasing the cost of concrete construction, the present invention can consume and utilize a large amount of electrolytic manganese slag and red mud, realize the harmless treatment and good resource reuse of electrolytic manganese slag and red mud, and has good economic benefits. Detailed Implementation

[0080] To enable those skilled in the art to more clearly understand the technical solutions described in this invention, the following embodiments are provided for illustration. It should be noted that the following embodiments do not constitute a limitation on the scope of protection claimed by this invention.

[0081] Unless otherwise specified, the raw materials, reagents or devices used in the following examples are available from conventional commercial sources or can be obtained by existing known methods.

[0082] The specifications of the raw materials used in the embodiments of the present invention are as follows:

[0083] (1) The electrolytic manganese slag is all water-washed slag stored in the Guangxi manganese slag warehouse. 80% of ammonia nitrogen and manganese have been recovered. The moisture content is 20-30%, and the particle size is concentrated in the range of 2.5-6.5μm. The leachate is acidic with a pH value of 4.5. In terms of mass percentage, the electrolytic manganese slag includes CaO 10%, SiO2 35%, Al2O3 6%, Fe2O3 22%, MnO 8%, and SO3 19%.

[0084] (2) The red mud, by mass percentage, includes 12.54% SiO2, 23.24% Al2O3, 36.62% Fe2O3, 8.54% CaO, 6.86% Na2O, 2.21% TiO2, and the remainder is loss on ignition.

[0085] (3) Quicklime is a high-calcium ash, which, by mass percentage, includes 89.6% CaO, 5.75% MgO, and 24.65% SiO.

[0086] (4) After the modifier is mixed with the modified micro powder of electrolytic manganese slag-red mud, the content of CaO is maintained at 15-20%, Al2O3 at 15-25%, SiO2 at 20-45%, and Fe2O3 at 5-15%.

[0087] (5) Fine aggregate is stone powder and / or river sand with a particle size of less than 4.75 mm.

[0088] (6) The water-reducing agent is a polycarboxylate high-efficiency water-reducing agent with a mass fraction of 1%.

[0089] (7) The coarse aggregate is a three-grade crushed stone mixture with a particle size of 5 mm or less than or equal to 10 mm, a particle size of 10 mm or less than 20 mm, and a particle size of 20 mm or less than or equal to 31.5 mm. The mass percentages of the three-grade crushed stone are 30%, 40%, and 30%, respectively.

[0090] Example 1

[0091] An electrolytic manganese slag-red mud concrete material, by weight, comprises 10 parts of modified electrolytic manganese slag-red mud powder, 12 parts of steel slag modifier, 20 parts of fine aggregate river sand, 50 parts of coarse aggregate, 8 parts of water, and 1 part of polycarboxylate superplasticizer.

[0092] By mass percentage, the raw material components of the modified micro powder of electrolytic manganese slag-red mud include 36% electrolytic manganese slag, 46% red mud, 8% quicklime, 5% ammonia nitrogen curing agent superphosphate, 2% heavy metal ion stabilizer ferric hydroxide, 2% dispersant sodium pyrophosphate, and 1% grinding aid triethanolamine.

[0093] A method for preparing electrolytic manganese slag-red mud concrete material includes the following steps:

[0094] (1) Add electrolytic manganese slag, red mud, quicklime, superphosphate, ferric hydroxide and sodium pyrophosphate to the mixer by mass percentage and mix thoroughly for 10 min; let the wet-mixed mixture stand for 8 h to allow it to react fully and obtain a wet mixture.

[0095] (2) Place the wet mixture obtained in step (1) into a blower dryer, dry it to constant weight, crush the dry material with a crusher, pass it through a 10mm square hole sieve, and collect the fine particulate material.

[0096] (3) Add the grinding aid triethanolamine to the fine particulate material obtained in step (2) and ball mill it for 40 minutes (20 minutes in the forward direction and 20 minutes in the reverse direction) to obtain finely ground and uniformly mixed micro powder, namely electrolytic manganese slag-red mud modified micro powder.

[0097] (4) According to the mass fraction, the electrolytic manganese slag-red mud modified micro powder obtained in step (3) is mixed evenly with steel slag, fine aggregate river sand, polycarboxylate superplasticizer and water, and then coarse aggregate is added and stirred for 3 minutes to obtain electrolytic manganese slag-red mud concrete material.

[0098] Example 2

[0099] An electrolytic manganese slag-red mud concrete material, by weight, comprises 8 parts of modified electrolytic manganese slag-red mud powder, 10 parts of slag modifier, 25 parts of fine aggregate stone powder, 55 parts of coarse aggregate, 6 parts of water, and 2 parts of polycarboxylate superplasticizer.

[0100] By mass percentage, the raw material components of the modified micro powder of electrolytic manganese slag-red mud include 36% electrolytic manganese slag, 46% red mud, 8% quicklime, 5% ammonia nitrogen curing agent phosphogypsum, 2% heavy metal ion stabilizer polyaluminum sulfate, 2% dispersant triethylhexyl phosphate, and 1% grinding aid ethylene glycol.

[0101] A method for preparing electrolytic manganese slag-red mud concrete material includes the following steps:

[0102] (1) Add electrolytic manganese slag, red mud, quicklime, phosphogypsum, polyaluminum sulfate and triethylhexylphosphoric acid to a mixer by mass percentage and mix thoroughly for 10 min. Let the wet-mixed material stand for 8 h to allow it to react fully and obtain a wet mixture.

[0103] (2) Place the wet mixture obtained in step (1) into a blower dryer, dry it to constant weight, crush the dry material with a crusher, pass it through a 10mm square hole sieve, and collect the fine particulate material.

[0104] (3) Add grinding aid ethylene glycol to the fine particulate material obtained in step (2) and ball mill for 40 min (20 min forward ball milling and 20 min reverse ball milling) to obtain finely ground and uniformly mixed micro powder, namely electrolytic manganese slag-red mud modified micro powder.

[0105] (4) According to the mass fraction, the modified micro powder of electrolytic manganese slag-red mud obtained in step (3) is mixed evenly with slag, fine aggregate stone powder, polycarboxylate superplasticizer and water, and then coarse aggregate is added and stirred for 4 minutes to obtain electrolytic manganese slag-red mud concrete material.

[0106] Example 3

[0107] An electrolytic manganese slag-red mud concrete material, by weight, comprises 10 parts of modified electrolytic manganese slag-red mud powder, 12 parts of fly ash as a modifier, 20 parts of fine aggregate stone powder, 40 parts of coarse aggregate, 9 parts of water, and 2 parts of polycarboxylate superplasticizer.

[0108] By mass percentage, the raw material components of the modified micro powder of electrolytic manganese slag-red mud include 36% electrolytic manganese slag, 46% red mud, 8% quicklime, 5% ammonia nitrogen curing agent MgO, 2% heavy metal ion stabilizer disodium hydrogen phosphate, 2% dispersant polyacrylamide, and 1% grinding aid sodium acetate.

[0109] A method for preparing electrolytic manganese slag-red mud concrete material includes the following steps:

[0110] (1) Add electrolytic manganese slag, red mud, quicklime, MgO, disodium hydrogen phosphate and polyacrylamide to the mixer according to the mass percentage, and mix thoroughly for 10 min; let the wet-mixed mixture stand for 10 h to allow it to react fully and obtain a wet mixture.

[0111] (2) Place the wet mixture obtained in step (1) into a blower dryer, dry it to constant weight, crush the dry material with a crusher, pass it through a 10mm square hole sieve, and collect the fine particulate material.

[0112] (3) Add grinding aid sodium acetate to the fine particulate material obtained in step (2) and ball mill for 40 min (20 min forward ball milling and 20 min reverse ball milling) to obtain finely ground and uniformly mixed micro powder, namely electrolytic manganese slag-red mud modified micro powder.

[0113] (4) According to the mass fraction, the modified micro powder of electrolytic manganese slag-red mud obtained in step (3) is mixed evenly with fly ash, fine aggregate stone powder, polycarboxylate superplasticizer and water, and then coarse aggregate is added and stirred for 3 minutes to obtain electrolytic manganese slag-red mud concrete material.

[0114] Example 4

[0115] An electrolytic manganese slag-red mud concrete material, by weight, comprises 8 parts of modified electrolytic manganese slag-red mud powder, 12 parts of blast furnace slag modifier, 20 parts of fine aggregate river sand, 55 parts of coarse aggregate, 8 parts of water, and 1 part of polycarboxylate superplasticizer.

[0116] By mass percentage, the raw material components of the modified micro powder of electrolytic manganese slag-red mud include 36% electrolytic manganese slag, 46% red mud, 8% quicklime, 5% ammonia nitrogen curing agent Na3PO4·12H2O, 2% heavy metal ion stabilizer aluminum hydroxide, 2% dispersant sodium tripolyphosphate, and 1% grinding aid triethanolamine.

[0117] A method for preparing electrolytic manganese slag-red mud concrete material includes the following steps:

[0118] (1) Add electrolytic manganese slag, red mud, quicklime, Na3PO4·12H2O, aluminum hydroxide and sodium tripolyphosphate to a mixer according to the mass percentage, and mix thoroughly for 10 min; let the wet-mixed mixture stand for 9 h to allow it to react fully and obtain a wet mixture.

[0119] (2) Place the wet mixture obtained in step (1) into a blower dryer, dry it to constant weight, crush the dry material with a crusher, pass it through a 10mm square hole sieve, and collect the fine particulate material.

[0120] (3) Add the grinding aid triethanolamine to the fine particulate material obtained in step (2) and ball mill it for 40 minutes (20 minutes in the forward direction and 20 minutes in the reverse direction) to obtain finely ground and uniformly mixed micro powder, namely electrolytic manganese slag-red mud modified micro powder.

[0121] (4) According to the mass fraction, the electrolytic manganese slag-red mud modified micro powder obtained in step (3) is mixed evenly with blast furnace slag, fine aggregate river sand, polycarboxylate superplasticizer and water, and then coarse aggregate is added and stirred for 5 minutes to obtain electrolytic manganese slag-red mud concrete material.

[0122] Comparative Example 1

[0123] The only difference between Comparative Example 1 and Example 1 is that Comparative Example 1 uses an equal amount of silicate cement to replace the modifier; otherwise, they are the same as in Example 1.

[0124] Comparative Example 2

[0125] The only difference between Comparative Example 2 and Example 1 is that Comparative Example 2 uses equal amounts of electrolytic manganese slag and red mud (4 parts each) to replace the electrolytic manganese slag-red mud modified micro powder, while the rest is the same as Example 1.

[0126] Performance testing

[0127] The flexural strength and wear of the electrolytic manganese slag-red mud concrete materials prepared in Examples 1-4 and Comparative Examples 1-2 were tested, and the test results are shown in Table 1.

[0128] The specific test method for flexural strength is as follows:

[0129] (1) The slurry of the concrete materials obtained in Examples 1-4 and Comparative Examples 1-2 was poured into a standard concrete mold of 150×150×600mm. Three sets of concrete test blocks were poured for each example and comparative example.

[0130] (2) Place the concrete test block obtained in step (1) into a standard curing chamber with a temperature of 20℃ and a relative humidity of 90% for curing and demolding. On the 28th day, apply a bending load using a fully automatic pressure testing machine. Test 3 test blocks at each age and take the average value as the bending tensile strength of the concrete material at that age.

[0131] The wear test method shall be in accordance with GB / T 50081-2019.

[0132] Performance standards require that the flexural strength and wear rate must meet the corresponding standard technical strength requirements of the road surface. Referring to JTG D40-2011 "Design Specifications for Highway Cement Concrete Pavement" and JTG / T F30-2014 "Technical Details for Construction of Highway Cement Concrete Pavement," the 28-day flexural strength of traffic road concrete pavement must reach 5 MPa, and the wear rate ≤ 3 kg / m². 2 .

[0133] Table 1: Performance test results of electrolytic manganese slag-red mud concrete materials prepared in Examples 1-4 and Comparative Examples 1-2

[0134] Flexural strength / MPa 5.5 6.4 6.2 5.8 4.2 3.7 <![CDATA[Wear loss / Kg / m 2 > 2.8 2.2 2.5 2.4 4.2 3.6

[0135] As shown in Table 1, the 28-day flexural tensile strength of the electrolytic manganese slag and red mud concrete materials in Examples 1-4 of this invention is greater than 5 MPa, and the abrasion loss is less than 3 kg / m. 2 All of these exceed the requirements of current technical standards.

[0136] Comparative Example 1 replaced the modifier with silicate cement, but did not optimize the calcium, silicon, and aluminum content of the components, which limited the synergistic activation effect. The resulting concrete material had an average 28-day flexural tensile strength of 4.2 MPa and an abrasion loss of 4.2 kg / m³. 2 It cannot meet the heavy traffic requirements of first-class highways.

[0137] Comparative Example 2 did not modify the electrolytic manganese slag and red mud; instead, it directly added them to prepare concrete. The resulting concrete pavement material had an average 28-day flexural tensile strength of 3.7 MPa and an abrasion loss of 3.6 kg / m². 2 The overall performance is further reduced.

[0138] Therefore, it can be seen that the modifier and the modified micro powder of electrolytic manganese slag-red mud in the concrete pavement material of the present invention are a whole, and the components need to complement each other and work synergistically. Omitting any of the components, or directly mixing red mud and electrolytic manganese slag with cement to prepare concrete, will result in a significant reduction in the strength of the pavement material and an increase in wear, which will not meet the requirements for the use of pavement materials.

[0139] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A concrete material, characterized in that, By weight, the raw material components of the concrete material include 7-11 parts of electrolytic manganese slag-red mud modified micro powder, 9-13 parts of modifier, 13-27 parts of fine aggregate, and 35-60 parts of coarse aggregate. The raw material composition of the modified electrolytic manganese slag-red mud micro powder, by mass percentage, consists of 30-47% electrolytic manganese slag, 35-55% red mud, 6.5-10% quicklime, 4.0-6.5% ammonia nitrogen curing agent, 1.6-2.4% heavy metal ion stabilizer, 1.6-2.4% dispersant, and 0.8-1.2% grinding aid. The heavy metal ion stabilizer includes at least one of aluminum hydroxide, iron hydroxide, polyaluminum sulfate, layered double hydroxide, calcined layered double hydroxide, organic chelating agent, disodium hydrogen phosphate, superphosphate, and lignin-based triaminotriethylamine salts; the ammonia nitrogen curing agent includes at least one of Na3PO4, NaH2PO4, MgSO4, Na3PO4·12H2O, NaH2PO4·12H2O, MgSO4·7H2O, superphosphate, phosphogypsum leachate, phosphogypsum, and MgO. The modifier is selected from at least one of blast furnace slag, waste incineration slag, and non-ferrous metallurgical slag. The preparation method of the modified micro powder of electrolytic manganese slag-red mud includes the following steps: The raw material components of the modified electrolytic manganese slag-red mud powder are mixed, reacted, and ground to obtain the modified electrolytic manganese slag-red mud powder.

2. The concrete material according to claim 1, characterized in that, The raw material components of the concrete material also include water-reducing agents and at least one of the following: water.

3. The method for preparing the concrete material according to any one of claims 1-2, characterized in that, Includes the following steps: The raw material components are mixed and reacted to obtain the concrete material.

4. The application of the concrete material according to any one of claims 1-2 in the construction field.