CN115477857B - Preparation method of modified guano Dan Chaoxi dry powder - Google Patents

Preparation method of modified guano Dan Chaoxi dry powder Download PDF

Info

Publication number
CN115477857B
CN115477857B CN202210882495.XA CN202210882495A CN115477857B CN 115477857 B CN115477857 B CN 115477857B CN 202210882495 A CN202210882495 A CN 202210882495A CN 115477857 B CN115477857 B CN 115477857B
Authority
CN
China
Prior art keywords
dan
chaoxi
particles
dry powder
modified
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202210882495.XA
Other languages
Chinese (zh)
Other versions
CN115477857A (en
Inventor
张海军
梁子龙
王明超
周志吉
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Civil Aviation University of China
Original Assignee
Civil Aviation University of China
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Civil Aviation University of China filed Critical Civil Aviation University of China
Priority to CN202210882495.XA priority Critical patent/CN115477857B/en
Publication of CN115477857A publication Critical patent/CN115477857A/en
Application granted granted Critical
Publication of CN115477857B publication Critical patent/CN115477857B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
    • C09C1/02—Compounds of alkaline earth metals or magnesium
    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
    • A62D1/00—Fire-extinguishing compositions; Use of chemical substances in extinguishing fires
    • A62D1/0007—Solid extinguishing substances
    • A62D1/0014—Powders; Granules
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B25/00—Phosphorus; Compounds thereof
    • C01B25/16—Oxyacids of phosphorus; Salts thereof
    • C01B25/26—Phosphates
    • C01B25/45—Phosphates containing plural metal, or metal and ammonium
    • C01B25/451—Phosphates containing plural metal, or metal and ammonium containing metal and ammonium
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
    • C09C3/006—Combinations of treatments provided for in groups C09C3/04 - C09C3/12
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
    • C09C3/04—Physical treatment, e.g. grinding, treatment with ultrasonic vibrations
    • C09C3/041—Grinding
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
    • C09C3/06—Treatment with inorganic compounds
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
    • C09C3/08—Treatment with low-molecular-weight non-polymer organic compounds
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
    • C09C3/10—Treatment with macromolecular organic compounds
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
    • C09C3/12—Treatment with organosilicon compounds
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/12—Surface area
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/14—Pore volume
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/90—Other properties not specified above

Abstract

A preparation method of modified guano Dan Chaoxi dry powder. The raw materials are taken from supernatant liquid rich in nitrogen and phosphorus of a sewage plant, heavy metal ions in the sewage are removed by utilizing a cation selective permeation membrane, then nitrogen-magnesium-phosphorus ratio and pH value in the solution are regulated to generate struvite precipitation, and pure struvite particles are obtained through filtration and drying. Then the mixture is ground into superfine grain size by air classification, bird droppings Dan Chaoxi particles with equivalent diameter of 1.5-20 mu m are modified by an organic surface modifier, and then the bird droppings Dan Chaoxi particles are mixed with silicone oil and hydrophobic nano SiO 2 Mixing, stirring, grinding and drying the talcum powder and the magnesium stearate. According to the invention, the bird dung stone material is optimized and improved, particles are fully refined to meet the superfine requirement, the specific surface area of the bird dung stone material is increased, and the contact area between fire extinguishing particles and flame is increased; solves the problem of dry powder agglomeration, promotes the overall thermal stability, greatly facilitates the stock storage, is favorable for starting pyrolysis after particles reach the root of flame, gives full play to the fire extinguishing effect and has excellent smoke suppression effect.

Description

Preparation method of modified guano Dan Chaoxi dry powder
Technical Field
The invention relates to a preparation method of modified bird droppings Dan Chaoxi dry powder, and belongs to the technical field of fire-fighting dry powder.
Background
The particle size of the fire extinguishing component used in the common dry powder is usually between 10 and 75 mu m, and the single particles have the defects of rapid sedimentation, poor dispersivity, small specific surface area and the like because of relatively large mass, so that the capability of capturing free radicals and active groups is relatively poor, and the fire extinguishing capability is limited. The preparation of ultrafine dry powder which has smaller particle size, good fluidity, large specific surface area, high activity, stable dispersion and long-time suspension in air becomes the key for improving the fire extinguishing capability of the dry powder. In recent years, ultrafine dry powder has attracted general attention from vast scholars and fire-fighting enterprises due to its excellent fire extinguishing performance, and series of researches on preparation, modification and the like of ultrafine dry powder have been carried out.
Magnesium ammonium phosphate also known as struvite (MgNH) 4 PO 4 ·6H 2 O), a naturally occurring orthophosphate mineral, precipitates in aqueous systems containing high concentrations of ammonium and phosphate, and was first found in sewage treatment plants. Struvite is a crystallized substance in a pipeline of a sewage treatment plant, and if the struvite is not cleaned for a long time, crystallization is easy to generate to block the pipeline, and a large amount of struvite is produced every year. In order to reduce the cost of waste treatment and to increase the efficiency of chemical treatment processes, it is desirable to find alternative uses for such materials, as a low cost starting material, exploiting its fire extinguishing potential. Struvite is used as a fire extinguishing main body and can replace traditional BC and ABC dry powder. The substances are heated and decomposed to generate water and ammonia gas, the temperature of a fire scene can be reduced, the peripheral oxygen concentration is diluted, and the final products magnesium orthophosphate and magnesium pyrophosphate form a compact isolation layer. The fire extinguishing mechanism is similar to that of the traditional sodium bicarbonate and ammonium dihydrogen phosphate. However, the pyrolysis end products of sodium bicarbonate and ammonium dihydrogen phosphate can generate acidic substances to corrode equipment, and the pyrolysis products of struvite are magnesium orthophosphate, basic magnesium orthophosphate and pyrophosphoric acid, so that the equipment is non-corrosive and harmless to the environment, and therefore, the guanite pyrolysis end products have great application potential and development value.
However, the common guano Dan Gan powder generates fewer P-O groups capable of killing OH and H free radicals during pyrolysis, so that the capability of capturing the free radicals is limited; and secondly, the pyrolysis temperature of the common bird droppings Dan Ganfen is low, and pyrolysis starts before the bird droppings reach the root of the flame, so that the effective endothermic process reacts in advance. The lower pyrolysis temperature has a disadvantage over ABC or BC dry powders because it places higher demands on storage temperature and is not conducive to long-term storage.
Disclosure of Invention
In order to solve the problems, the invention aims to provide a preparation method of modified struvite ultrafine dry powder, which is characterized in that the surfaces of struvite particles are coated by a silane coupling agent or phosphorus-containing organosilicon to improve the overall thermal stability and hydrophobic effect and generate a large number of P-O groups during pyrolysis so as to improve the fire extinguishing performance.
In order to achieve the above purpose, the preparation method of the modified struvite ultrafine dry powder provided by the invention comprises the following steps in sequence:
(1) Selecting supernatant of a sewage treatment plant as a raw material, adding porous solid substances, fully mixing and uniformly stirring, removing heavy metal ions by using a physical adsorption principle, standing for 1.5-2.5 hours, and filtering off bottom sediment to obtain purified supernatant;
(2) Adding water-soluble normal magnesium salt and normal ammonium salt into the purified supernatant, controlling the molar ratio of Mg to N to P in the solution to be 1.5-2:1.5-2:1, then adding alkali liquor to adjust the pH to be 9-10, stirring at normal temperature, filtering to obtain bottom precipitate, and drying at 30-40 ℃ to obtain struvite particles with the particle diameter D50 of 50-70 mu m;
(3) Drying the struvite particles, and then crushing and refining the particles by using an air classifying mill to obtain the struvite Dan Chaoxi particles with the equivalent diameter smaller than 20 mu m;
(4) Dissolving an organic surface modifier into an ethanol solution serving as a dispersing agent, then dropwise adding a saturated citric acid solution to maintain the pH value to be 3-4, magnetically stirring for 1.5-2.5 hours at the temperature of 60-70 ℃, and then cooling to 30-40 ℃ to prepare a prehydrolysis solution;
(5) Adding the bird droppings Dan Chaoxi particles prepared in the step (3) into the prehydrolysis solution prepared in the step (4), and placing the bird droppings Dan Chaoxi particles in a penetrating type ultrasonic dispersing machine for ultrasonic dispersion to obtain a suspension; then stirring uniformly by using a cantilever stirrer to obtain emulsion, thereby modifying the bird droppings Dan Chaoxi particles:
(6) Drying the emulsion obtained in the step (5) in a vacuum freeze dryer for 18-30h to obtain modified guano Dan Chaoxi particles;
(7) Adding the modified guano Dan Chaoxi particles obtained in the step (6) into a rotor mill for drying, scattering and modifying, and reducing the agglomerated dry powder particles to the original particle size; then adding silicone oil, hydrophobic nano silicon dioxide, talcum powder and magnesium stearate to carry out dry powder modification; and then heating to 30-40 ℃ and drying for 8-16 hours to obtain the modified bird dung Dan Chaoxi dry powder.
In the step (1), the supernatant fluid of the sewage treatment plant is a phosphorus-rich solution containing urban domestic sewage or farm sewage; the porous solid substance is at least one of porous adsorption materials including activated carbon, chitosan resin, acidified sepiolite and aluminum zirconium pillared montmorillonite.
In step (2), the normal magnesium salt is selected from at least one of magnesium chloride, magnesium nitrate and magnesium sulfate; the ammonium salt of normal water is at least one selected from ammonium chloride, ammonium sulfate and ammonium fluoride; the alkali liquor is at least one of ammonia water, potassium hydroxide and sodium hydroxide aqueous solution; the stirring speed is 500-900rpm, and the stirring time is 20-40min.
In the step (3), the rotating speed of the air classifying mill is 3000-4000rpm, and the treatment air quantity is 400-600m/h.
In the step (4), the organic surface modifier is selected from at least one of a silane coupling agent and a phosphorus-containing organosilicon DOPO-VTS; wherein the silane coupling agent is selected from at least one of gamma-aminopropyl triethoxysilane, gamma-aminopropyl trimethoxysilane, gamma-aminopropyl methyldiethoxysilane, aminopropyl silane hydrolysate, gamma-aminopropyl methyldimethoxy silane, N-phenyl-gamma-aminopropyl trimethoxysilane, N-beta- (aminoethyl) -gamma-aminopropyl methyldimethoxy silane, N-N diethyl aminopropyl trimethoxysilane, N-N dimethyl aminopropyl trimethoxysilane, N-beta- (aminoethyl) -aminopropyl triethoxysilane, gamma-diethylenetriaminopropyl methyldimethoxy silane, gamma-diethylenetriaminopropyl trimethoxysilane, bis- (gamma-trimethoxysilylpropyl) amine, bis- (gamma-triethoxysilylpropyl) amine, gamma-piperazinylpropyl methyldimethoxy silane, N-phenylaminomethyl triethoxysilane, gamma-diethylaminomethyl triethoxysilane.
In the step (5), the mass ratio of the guano Dan Chaoxi particles to the ethanol solution in the prehydrolysis solution is 1-2.5:5, a step of; the mass ratio of the organic surface modifier to the struvite ultrafine particles in the prehydrolysis solution is 3-5:100; the working power of the penetrating ultrasonic dispersion machine is 150-250w, the total working time is 15-25min, the single working time is 5-10s, and the working gap is 8-12s; the rotation speed of the cantilever stirrer is 400-800rpm, and the stirring time is 4-6h.
In the step (7), the mass ratio of the modified struvite ultrafine particles to the silicone oil to the hydrophobic nano silicon dioxide to the talcum powder to the magnesium stearate is 100:1-1.5:4-6:1.5-2.5:1.5-2.5; reducing the agglomerated dry powder particles to the original particle size, wherein the rotating speed of a rotor mill is 800-1200rpm, and the treatment time is 20-30min; the rotating speed of the rotor mill is 1500-1700rpm during dry powder modification, and the treatment time is 1.5-3h.
The particle size of the hydrophobic nano silicon dioxide is 15nm, and the comparison area (BET) is 300+/-50 square meters per gram.
Compared with the prior art, the invention has the following beneficial effects:
(1) According to the invention, struvite is recovered by utilizing supernatant fluid of a sewage treatment plant, and the struvite material is optimized and improved, so that particles are fully refined to meet the superfine requirement (D90 is less than 20 mu m) to improve the specific surface area, so that on one hand, the contact area between fire extinguishing particles and flame is improved, and on the other hand, the pyrolysis rate of struvite is accelerated, and the fire extinguishing effect can be exerted more quickly;
(2) The invention can improve the overall thermal stability by introducing the phosphorus-containing organosilicon DOPO-VTS as the flame retardant material, delay the pyrolysis temperature of struvite, lead the integral particles to reach the pyrolysis process of the flame root and release a large amount of H 2 O and NH 3 Rapidly reducing the temperature of a fire scene; and the phosphorus-containing organosilicon DOPO-VTS is used as a silane coupling agent derivative, and the guanite dry powder can be integrally coated, so that the overall material has obvious hydrophobic effect;
(3) The invention can utilize phosphorus-containing organosilicon DOPO-VTS pyrolysis to generate a large number of P-O groups to efficiently capture OH and H free radicals, and well make up the disadvantages of struvite, thereby improving the overall fire extinguishing performance of the product;
(4) The main body of the struvite particles adopted by the invention is recycled sewage treatment plant products, so that the waste treatment cost is reduced, the fire extinguishing potential is developed, and the traditional BC and ABC dry powder can be replaced, thereby realizing waste recycling.
Drawings
FIG. 1 is a flow chart of a preparation method of modified struvite ultrafine dry powder.
FIG. 2 is a graph of 1m used in the experiments of the present invention 3 A schematic diagram of a small fire extinguishing platform.
FIG. 3a is a schematic diagram showing the mechanism of modification and hydrophobicity of the phosphorus-containing organosilicon DOPO-VTS modified struvite ultrafine dry powder prepared in example 1: FIG. 3b is an XPS spectrum of phosphorus-containing silicone DOPO-VTS modified bird droppings Dan Chaoxi dry powder and blank bird droppings Dan Chaoxi dry powder. Fig. 3c is an SEM image of a blank struvite ultrafine dry powder and a phosphorus-containing silicone DOPO-VTS modified struvite Dan Chaoxi dry powder.
FIG. 4 is a graph comparing SEM morphology features of phosphorus-containing organosilicon DOPO-VTS modified struvite ultrafine dry powder, blank struvite ultrafine dry powder and commercial ABC ultrafine dry powder prepared in example 1, wherein FIG. 4a, b are phosphorus-containing organosilicon DOPO-VTS modified struvite Dan Chaoxi dry powder, FIG. 4c, d are blank struvite ultrafine dry powder, and FIG. 4e, f are commercial ABC ultrafine dry powder.
Fig. 5 is a graph comparing the morphology characteristics of the ultra-fine powder of phosphorus-containing silicone DOPO-VTS modified struvite prepared in example 1 with that of blank struvite Dan Chaoxi at 150, 200, 250 and 700 ℃, wherein fig. 5a-d are the dry powder of phosphorus-containing silicone DOPO-VTS modified struvite Dan Chaoxi and fig. 5e-h are the dry powder of blank struvite Dan Chaoxi.
FIGS. 6a, b are adsorption and desorption curves of phosphorus-containing organosilicon DOPO-VTS modified struvite ultrafine powder prepared in example 1 with blank struvite ultrafine powder and commercial ABC ultrafine powder; FIGS. 6c and d are adsorption and desorption curves of the superfine dry powder of phosphorus-containing organosilicon DOPO-VTS modified struvite prepared in example 1 and the dry powder of blank struvite Dan Chaoxi at 150, 200, 250 and 700 ℃.
FIG. 7 is a graph comparing thermogravimetric data of phosphorus-containing organosilicon DOPO-VTS modified struvite ultrafine dry powder, blank struvite ultrafine dry powder and commercial ABC ultrafine dry powder prepared in example 1, wherein FIG. 7a is a Thermogravimetric (TG) curve, FIG. 7b is a Derivative Thermogravimetric (DTG) curve, and FIG. 7c is a Differential Scanning Calorimeter (DSC) curve.
FIGS. 8a and b are graphs showing XRD component comparison analysis of a blank struvite ultrafine dry powder and a phosphorus-containing organosilicon DOPO-VTS modified struvite Dan Chaoxi dry powder prepared in example 1 at different temperatures, respectively.
FIGS. 9a, b and c are video shots of fire extinguishing experiments of commercial ABC ultrafine dry powder, blank struvite ultrafine dry powder and phosphorus-containing organosilicon DOPO-VTS modified guano Dan Chaoxi dry powder prepared in example 1, respectively.
FIG. 10 is a graph showing the smoke suppression effect (CO concentration) of phosphorus-containing organosilicon DOPO-VTS modified struvite ultrafine powder prepared in example 1 of the invention in a fire scene compared with a blank struvite ultrafine powder and commercial ABC ultrafine dry powder.
Detailed Description
In order to further describe the technical means and effects adopted by the present invention for achieving the intended purpose, the following detailed description will refer to the specific implementation, the features and the effects according to the present invention with reference to the accompanying drawings and the preferred embodiments.
Example 1
As shown in fig. 1, the preparation method of the modified guano Dan Chaoxi dry powder provided in this embodiment includes the following steps performed in sequence:
(1) Selecting supernatant fluid of a sewage treatment plant as a raw material, adding aluminum zirconium pillared montmorillonite, fully mixing and uniformly stirring, and removing heavy metal ions by utilizing a physical adsorption principle; standing for 2 hours, and filtering to remove sediment at the bottom to obtain a purified supernatant;
(2) Adding magnesium sulfate and ammonium sulfate which are easy to dissolve in water into the purified supernatant, controlling the molar ratio of Mg to N to P in the solution to be 1.5:1.5:1, then adding ammonia water to adjust the pH to be 9, stirring at normal temperature, setting the rotating speed to 800rpm, stirring for 30min, filtering to obtain bottom sediment, and drying at 30 ℃ to obtain struvite particles with the particle size D50 of 50 mu m;
(3) Drying the struvite particles, and then crushing and refining by using an air classifying mill, wherein the rotating speed is 3500rpm, and the treatment air quantity is 500m/h; under the action of centrifugal force, shearing, friction, collision and other comprehensive forces, coarse and fine materials are separated through program regulation, particles reaching 20 mu m enter a collector along with air flow, and the coarse particles return to a crushing cylinder to be continuously crushed until all struvite particles are smaller than 20 mu m, so as to obtain struvite Dan Chaoxi particles;
(4) Dissolving phosphorus-containing organosilicon DOPO-VTS into ethanol solution serving as a dispersing agent, then dropwise adding saturated citric acid solution to maintain the pH value to be 3, magnetically stirring for 2 hours at the temperature of 70 ℃, and then cooling to 30 ℃ to prepare a prehydrolysis solution;
(5) Adding the bird droppings Dan Chaoxi particles prepared in the step (3) into the prehydrolysis solution prepared in the step (4), and placing the bird droppings Dan Chaoxi particles in a penetrating type ultrasonic dispersing machine for ultrasonic dispersion to obtain a suspension; the mass ratio of the struvite ultrafine particles to the ethanol solution in the prehydrolysis solution is 2:5, a step of; the mass ratio of the phosphorus-containing organosilicon DOPO-VTS to the struvite ultrafine particles in the prehydrolysis solution is 3:100; the working power of the penetrating ultrasonic dispersion machine is 200w, the total working time is 20min, the single working time is 8s, and the working gap is 10s; then stirring uniformly by using an cantilever stirrer to obtain emulsion, wherein the rotating speed of the cantilever stirrer is 400rpm, and the stirring time is 5 hours; the bird droppings Dan Chaoxi particles are modified by the following steps:
(6) Drying the emulsion obtained in the step (5) for 24 hours in a vacuum freeze dryer to obtain modified guano Dan Chaoxi particles;
(7) Adding the modified guano Dan Chaoxi particles obtained in the step (6) into a rotor mill for drying, scattering and modifying, and reducing the agglomerated dry powder particles to the original particle size; the rotating speed is 1000rpm, and the treatment time is 20min; then adding silicone oil, hydrophobic nano silicon dioxide, talcum powder and magnesium stearate to carry out dry powder modification; the mass ratio of modified struvite ultrafine particles, silicone oil, hydrophobic nano silicon dioxide (particle diameter: 15nm, comparative area (BET): 300+ -50 square meters per gram), talcum powder and magnesium stearate is 100:1:4:1.5:1.5; and then heating to 40 ℃ and drying for 12 hours to obtain the modified bird dung Dan Chaoxi dry powder.
Example 2
As shown in fig. 1, the preparation method of the modified guano Dan Chaoxi dry powder provided in this embodiment includes the following steps performed in sequence:
(1) Selecting supernatant of a sewage treatment plant as a raw material, adding acidified sepiolite, fully mixing and uniformly stirring, and removing heavy metal ions by utilizing a physical adsorption principle; standing for 1.5 hours, and filtering to remove bottom sediment to obtain a purified supernatant;
(2) Adding magnesium sulfate and ammonium sulfate which are easy to dissolve in water into the purified supernatant, controlling the molar ratio of Mg to N to P in the solution to be 1:1, then adding ammonia water to adjust the pH to be 10, stirring at normal temperature, setting the rotating speed to be 800rpm, stirring for 30min, filtering to obtain bottom sediment, and drying at 30 ℃ to obtain struvite particles with the particle size D50 of 55 mu m;
(3) Drying the struvite particles, and then crushing and refining by using an air classifying mill, wherein the rotating speed is 3000rpm, and the treatment air quantity is 500m/h; under the action of centrifugal force, shearing, friction, collision and other comprehensive forces, coarse and fine materials are separated through program regulation, particles reaching 20 mu m enter a collector along with air flow, and the coarse particles return to a crushing cylinder to be continuously crushed until all struvite particles are smaller than 20 mu m, so as to obtain struvite Dan Chaoxi particles;
(4) Dissolving gamma-aminopropyl triethoxysilane into ethanol solution serving as a dispersing agent, then dropwise adding saturated citric acid solution to maintain the pH value to be 3, magnetically stirring for 2 hours at the temperature of 70 ℃, and then cooling to 30 ℃ to prepare a prehydrolysis solution;
(5) Adding the bird droppings Dan Chaoxi particles prepared in the step (3) into the prehydrolysis solution prepared in the step (4), and placing the bird droppings Dan Chaoxi particles in a penetrating type ultrasonic dispersing machine for ultrasonic dispersion to obtain a suspension; the mass ratio of the struvite ultrafine particles to the ethanol solution in the prehydrolysis solution is 2:5, a step of; the mass ratio of the gamma-aminopropyl triethoxysilane to the struvite ultrafine particles in the prehydrolysis solution is 3.5:100; the working power of the penetrating ultrasonic dispersion machine is 200w, the total working time is 20min, the single working time is 8s, and the working gap is 10s; then stirring uniformly by using an cantilever stirrer to obtain emulsion, wherein the rotating speed of the cantilever stirrer is 400rpm, and the stirring time is 5 hours; the bird droppings Dan Chaoxi particles are modified by the following steps:
(6) Drying the emulsion obtained in the step (5) for 24 hours in a vacuum freeze dryer to obtain modified guano Dan Chaoxi particles;
(7) Adding the modified guano Dan Chaoxi particles obtained in the step (6) into a rotor mill for drying, scattering and modifying, and reducing the agglomerated dry powder particles to the original particle size; the rotating speed is 1000rpm, and the treatment time is 20min; then adding silicone oil, hydrophobic nano silicon dioxide, talcum powder and magnesium stearate to carry out dry powder modification; the mass ratio of modified struvite ultrafine particles, silicone oil, hydrophobic nano silicon dioxide (particle diameter: 15nm, comparative area (BET): 300+ -50 square meters per gram), talcum powder and magnesium stearate is 100:1.2:5:2:2; and then heating to 40 ℃ and drying for 12 hours to obtain the modified bird dung Dan Chaoxi dry powder.
Example 3
As shown in fig. 1, the preparation method of the modified guano Dan Chaoxi dry powder provided in this embodiment includes the following steps performed in sequence:
(1) Selecting supernatant fluid of a sewage treatment plant as a raw material, adding active carbon, fully mixing and uniformly stirring, and removing heavy metal ions by utilizing a physical adsorption principle; standing for 2 hours, and filtering to remove sediment at the bottom to obtain a purified supernatant;
(2) Adding magnesium sulfate and ammonium sulfate which are easy to dissolve in water into the purified supernatant, controlling the molar ratio of Mg to N to P in the solution to be 1.2:1.2:1, then adding ammonia water to adjust the pH to be 9, stirring at normal temperature, setting the rotating speed to 900rpm, stirring for 30min, filtering to obtain bottom sediment, and drying at 30 ℃ to obtain struvite particles with the particle size D50 of 60 mu m;
(3) Drying the struvite particles, and then crushing and refining by using an air classifying mill, wherein the rotating speed is 4000rpm, and the treatment air quantity is 500m/h; under the action of centrifugal force, shearing, friction, collision and other comprehensive forces, coarse and fine materials are separated through program regulation, particles reaching 20 mu m enter a collector along with air flow, and the coarse particles return to a crushing cylinder to be continuously crushed until all struvite particles are smaller than 20 mu m, so as to obtain struvite Dan Chaoxi particles;
(4) Dissolving phosphorus-containing organosilicon DOPO-VTS into ethanol solution serving as a dispersing agent, then dropwise adding saturated citric acid solution to maintain the pH value to be 3, magnetically stirring for 2 hours at the temperature of 70 ℃, and then cooling to 40 ℃ to prepare a prehydrolysis solution;
(5) Adding the bird droppings Dan Chaoxi particles prepared in the step (3) into the prehydrolysis solution prepared in the step (4), and placing the bird droppings Dan Chaoxi particles in a penetrating type ultrasonic dispersing machine for ultrasonic dispersion to obtain a suspension; the mass ratio of the struvite ultrafine particles to the ethanol solution in the prehydrolysis solution is 2:5, a step of; the mass ratio of the phosphorus-containing organosilicon DOPO-VTS to the struvite ultrafine particles in the prehydrolysis solution is 3:100; the working power of the penetrating ultrasonic dispersion machine is 200w, the total working time is 20min, the single working time is 8s, and the working gap is 10s; then stirring uniformly by using an cantilever stirrer to obtain emulsion, wherein the rotating speed of the cantilever stirrer is 400rpm, and the stirring time is 5 hours; the bird droppings Dan Chaoxi particles are modified by the following steps:
(6) Drying the emulsion obtained in the step (5) for 24 hours in a vacuum freeze dryer to obtain modified guano Dan Chaoxi particles;
(7) Adding the modified guano Dan Chaoxi particles obtained in the step (6) into a rotor mill for drying, scattering and modifying, and reducing the agglomerated dry powder particles to the original particle size; the rotating speed is 1000rpm, and the treatment time is 20min; then adding silicone oil, hydrophobic nano silicon dioxide, talcum powder and magnesium stearate to carry out dry powder modification; the mass ratio of modified struvite ultrafine particles, silicone oil, hydrophobic nano silicon dioxide (particle diameter: 15nm, comparative area (BET): 300+ -50 square meters per gram), talcum powder and magnesium stearate is 100:1.5:6:2.5:2.5; and then heating to 40 ℃ and drying for 12 hours to obtain the modified bird dung Dan Chaoxi dry powder.
In the modified guano Dan Chaoxi dry powder prepared by the method, the main base material is struvite which is a sewage treatment product and is obtained by adjusting the nitrogen-magnesium-phosphorus ratio and the pH of supernatant liquid rich in nitrogen and phosphorus of a sewage plant and then crystallizing; ammonium chloride and magnesium chloride are used as an ammonium source and a magnesium source for adjusting the nitrogen-phosphorus ratio; the silane coupling agent and the phosphorus-containing organic silicon (DOPO-VTS) are used as organic surface modifiers in wet modification, so that on one hand, the problem of dry powder agglomeration can be effectively solved, the surface area of the dry powder is increased, the contact area between fire extinguishing particles and flame is increased, on the other hand, the surface of the particles is coated by the organic surface modification, the thermal stability of struvite dry powder is improved, so that the dry powder can be stored in a warehouse, the fire extinguishing effect is improved, and the smoke suppression effect is excellent; the silicone oil, the hydrophobic nano silicon dioxide, the talcum powder and the magnesium stearate are used as additives in dry modification, so that the comprehensive performance of the dry powder can be improved to meet the national requirements.
To verify the fire extinguishing effect of the modified struvite ultrafine dry powder provided in the above examples, the inventors performed fire extinguishing comparison using commercial ABC ultrafine dry powder and blank guano Dan Chaoxi dry powder as blank control samples. Wherein, commercial ABC superfine dry powder is obtained by purchasing, and the preparation method of blank guano Dan Chaoxi dry powder is as follows:
(1) Selecting supernatant fluid of a sewage treatment plant as a raw material, adding aluminum zirconium pillared montmorillonite, fully mixing and uniformly stirring, and removing heavy metal ions by utilizing a physical adsorption principle; standing for 2 hours, and filtering to remove sediment at the bottom to obtain a purified supernatant;
(2) Adding magnesium sulfate and ammonium sulfate which are easy to dissolve in water into the purified supernatant, controlling the molar ratio of Mg to N to P in the solution to be 1.5:1.5:1, then adding ammonia water to adjust the pH value to be 9, stirring at normal temperature, setting the rotating speed to be 800rpm, stirring for 30min, filtering to obtain bottom sediment, and drying at 30 ℃ to obtain struvite particles with the particle size D50 mu m;
(3) Drying the struvite particles, and then crushing and refining by using an air classifying mill, wherein the rotating speed is 3000rpm, and the treatment air quantity is 500m/h; under the action of centrifugal force, shearing, friction, collision and other comprehensive forces, coarse and fine materials are separated through program regulation, particles reaching 20 mu m enter a collector along with air flow, and the coarse particles return to a crushing cylinder to be continuously crushed until all struvite particles are smaller than 20 mu m, so as to obtain blank struvite Dan Chaoxi particles;
(4) Adding the blank guano Dan Chaoxi particles obtained in the step (3) into a rotor mill for drying, scattering and modifying, and reducing the agglomerated dry powder particles to the original particle size, wherein the rotating speed is 1000rpm, and the treatment time is 20min; then adding silicone oil, hydrophobic nano silicon dioxide (particle size: 15nm, comparative area (BET): 300+ -50 square meters per gram), talcum powder and magnesium stearate for dry powder modification, wherein the rotating speed is 1500rpm, and the treatment time is 1h; the mass ratio of the blank struvite ultrafine particles, the silicone oil, the hydrophobic nano silicon dioxide (particle diameter: 15nm, comparative area (BET): 300+/-50 square meters per gram), the talcum powder and the magnesium stearate is 100:1:4:1.5:1.5; heating to 40 ℃ and drying for 12 hours to obtain the blank bird droppings Dan Chaoxi dry powder.
The experimental procedure was as follows:
1) 50g of commercial ABC ultrafine dry powder, blank bird droppings Dan Chaoxi dry powder and phosphorus-containing organic silicon DOPO-VTS modified bird droppings Dan Chaoxi dry powder prepared in the embodiment 1 are weighed for a fire extinguishing experiment, the residual weight after the fire extinguishing experiment is weighed, the dry powder consumption and the fire extinguishing time are recorded, and the average value is taken for three times in each group;
2) The nitrogen with the pressure of 0.2MPa is used as a driving force, and the dry powder is released to a fire scene through a nozzle positioned right above a fire source;
3) 70ml of n-heptane and 50ml of distilled water are put into a 400 multiplied by 40mm oil basin, the oil basin is ignited by a flame gun, and the flame is kept stable by pre-burning for 60 seconds;
4) The whole experimental process is 1m as shown in FIG. 2 3 The small fire extinguishing platform is used for carrying out the fire extinguishing;
5) Placing the test sample in a high temperature furnace, and calcining at different temperatures (300 ℃, 400 ℃, 500 ℃, 600 ℃, 700 ℃) for 1h;
5) Verification of modified bird droppings Dan Baofu experiment: a blank guano Dan Chaoxi dry powder sample and a phosphorus-containing organosilicon DOPO-VTS modified guanite ultrafine dry powder sample were placed in a glass bottle containing 3/2 water and left to stand for 10min, the appearance and morphology of the two samples were observed by a scanning electron microscope analyzer (Nanosem 430, FEI), and the elements contained in the two samples were tested by XPS (Thermo esclab 250 XI), as shown in fig. 3.
As can be seen from fig. 3, after the struvite is modified by the organic surface modifier, the surface branches are increased; as shown in fig. 3b, the dry powder sample of the phosphorus-containing organosilicon DOPO-VTS modified bird droppings Dan Chaoxi contains P, si element in the phosphorus-containing organosilicon DOPO-VTS, which proves that the modification experiment is successful; the morphology observed by SEM (Nanosem 430, FEI) shows that the organic surface modifier coated the struvite particle surface, as shown in fig. 3 c.
6) And (3) observing the appearance of the sample: the phosphorus-containing silicone DOPO-VTS modified struvite ultrafine dry powder, blank struvite Dan Chaoxi dry powder and commercial ABC ultrafine dry powder were observed using a scanning electron microscope analyzer (Nanosem 430, FEI) as shown in FIG. 4.
The phosphorus-containing organosilicon DOPO-VTS modified bird droppings Dan Chaoxi dry powder and the blank bird droppings Dan Chaoxi dry powder after different temperature treatments are then made into SEM test samples, and the calcined morphology of the SEM test samples is observed by using a scanning electron microscope analyzer, as shown in FIG. 5.
As can be seen from FIG. 4, commercial ABC ultrafine dry powder and blank struvite ultrafine dry powder have larger particles, different sizes and serious agglomeration problems, while phosphorus-containing organosilicon DOPO-VTS modified guano Dan Chaoxi dry powder has smaller particles, uniform particle size and obviously improved agglomeration problems.
As can be seen from FIG. 5, the surfaces of the phosphorus-containing organosilicon DOPO-VTS modified bird droppings Dan Chaoxi dry powder and the blank bird droppings Dan Chaoxi dry powder which are calcined at different temperatures are porous, and a plurality of small particulate matters are fissioned with the increase of the temperature, so that the whole surface area is greatly increased, the free radical adsorption is facilitated, and the combustion reaction chain is blocked.
6) BET test: the adsorption and desorption curves of the phosphorus-containing organosilicon DOPO-VTS modified struvite ultrafine powder, the blank struvite Dan Chaoxi dry powder and the commercial ABC ultrafine powder are tested by using a microphone ASAP2460 adsorption and desorption instrument to obtain specific surface areas, pore diameters and pore volume, and then the phosphorus-containing organosilicon DOPO-VTS modified struvite Dan Chaoxi dry powder and the blank struvite Dan Chaoxi dry powder which are treated at different temperatures (200 ℃, 250 ℃ and 300 ℃) are subjected to the same test, as shown in fig. 6, table 1 and table 2.
Table 1 angle of repose and BTE data for samples
TABLE 2 variation of specific surface area at different temperatures
As can be seen from fig. 6: the specific surface area (38.18 square meters per gram) of the phosphorus-containing organosilicon DOPO-VTS modified guano Dan Chaoxi dry powder is larger than that of the blank struvite ultrafine dry powder, which means that the contact area of particles and flame is larger, the effective fire extinguishing components can be rapidly released, and the pyrolysis is more sufficient; the specific surface areas of the two samples calcined at different temperatures (200 ℃, 250 ℃ and 300 ℃) become larger along with the temperature increase, however, the specific surface area of the phosphorus-containing organic silicon DOPO-VTS modified bird droppings Dan Chaoxi dry powder is changed more greatly, which further proves that the pyrolysis is more sufficient and the flame inhibition effect is better.
8) TG-DSC explains its fire extinguishing mechanism: the phosphorus-containing organosilicon DOPO-VTS modified struvite superfine dry powder, blank struvite Dan Chaoxi dry powder and commercial ABC superfine dry powder were tested by using an STA 449C synchronous thermal analyzer to obtain a TG-DSC curve, and the fire extinguishing mechanism thereof was explained according to thermogravimetric data, as shown in figure 7.
As can be seen from fig. 7: the heat absorption capacity of the commercial ABC superfine dry powder is 714J/mg, the heat absorption capacities of the blank struvite superfine dry powder and the phosphorus-containing organosilicon DOPO-VTS modified struvite Dan Chaoxi dry powder are 876J/mg and 834J/mg respectively, which are higher than those of the commercial ABC superfine dry powder, the heat stability of the phosphorus-containing organosilicon DOPO-VTS modified struvite superfine dry powder is improved, and the temperature is raised to 100 ℃ from the initial 60 ℃, so that the stock storage is greatly facilitated, the pyrolysis is started after the particles reach the root of the flame, and the fire extinguishing effect is fully exerted.
9) The XRD analysis shows the pyrolysis products as shown in fig. 8 and table 3, and it can be seen from fig. 8: the pyrolysis products of the phosphorus-containing organosilicon DOPO-VTS modified and blank bird droppings Dan Chaoxi dry powder are magnesium orthophosphate, basic magnesium orthophosphate and pyrophosphoric acid, and the pyrolysis products have no corrosiveness to equipment and no harm to the environment.
TABLE 3 analysis of sample composition at different temperatures
10 Fig. 9 shows a screenshot of the fire extinguishing video, as can be seen from fig. 9: the fire extinguishing time of the phosphorus-containing organosilicon DOPO-VTS modified guano Dan Chaoxi dry powder is shortest (1.9 s), the blank guanite superfine dry powder (2.1 s) and the commercial ABC superfine dry powder has the worst contrast effect (2.5 s).
11 The variation of the CO concentration of the fire in the experiment was measured using a (testo 350) flue gas analyzer, as shown in fig. 10, the peak CO concentration after release of the phosphorus-containing silicone DOPO-VTS modified guano Dan Chaoxi dry powder of example 1 from the fire was 326ppm, which was lower than the commercial ABC ultrafine dry powder (420 ppm) and the blank struvite ultrafine dry powder (550 ppm), which further confirmed that the introduction of DOPO provided excellent smoke suppression effect to the modified sample.
The performance test results of the modified struvite ultrafine dry powder in the 3 examples are shown in table 4, wherein D50 (μm) is the particle size corresponding to the cumulative particle size distribution percentage of the sample reaching 50%; d90 (μm) is the particle size corresponding to the percentage of cumulative particle size distribution of the sample reaching 90%; bulk density (g/cm) 3 ) Refers to the ratio of the mass m of the powder to its filled volume V (including the voids between the dry powders) of the sample without vibration; flowability (g/s) refers to the time required for a sample to flow through a standard funnel of defined pore size with a quantity of dry powder; the contact angle (°) is the angle θ between the solid-liquid boundary lines of the sample and is a measure of the degree of wetting.
Table 4 results of test of modified struvite ultra-fine dry powder Performance and commercial ABC ultra-fine dry powder Performance in examples
The data comparison shows that the modified struvite superfine dry powder prepared by the invention meets the superfine requirement (D90 is less than 20 mu m), the bulk density, the fluidity and the contact angle reach the level of commercial ABC superfine dry powder, but the fire extinguishing time and the dry powder consumption during fire extinguishment are obviously superior to those of commercial ABC superfine dry powder, the effect is obvious, and the overall fire extinguishing performance is obviously improved.
The present invention is not limited to the above-mentioned embodiments, but is not limited to the above-mentioned embodiments, and any person skilled in the art can make some changes or modifications to the above-mentioned embodiments without departing from the scope of the present invention.

Claims (6)

1. A preparation method of modified guano Dan Chaoxi dry powder is characterized by comprising the following steps: the preparation method of the modified guano Dan Chaoxi dry powder comprises the following steps in sequence:
(1) Selecting supernatant of a sewage treatment plant as a raw material, adding porous solid substances, fully mixing and uniformly stirring, removing heavy metal ions by using a physical adsorption principle, standing for 1.5-2.5 hours, and filtering off bottom sediment to obtain purified supernatant;
(2) Adding water-soluble normal magnesium salt and normal ammonium salt into the purified supernatant, controlling the molar ratio of Mg to N to P in the solution to be 1.5-2:1.5-2:1, then adding alkali liquor to adjust the pH to be 9-10, stirring at normal temperature, filtering to obtain bottom precipitate, and drying at 30-40 ℃ to obtain struvite particles with the particle diameter D50 of 50-70 mu m;
(3) Drying the struvite particles, and then crushing and refining the particles by using an air classifying mill to obtain the struvite Dan Chaoxi particles with the equivalent diameter smaller than 20 mu m;
(4) Dissolving an organic surface modifier into an ethanol solution serving as a dispersing agent, then dropwise adding a saturated citric acid solution to maintain the pH value to be 3-4, magnetically stirring for 1.5-2.5 hours at the temperature of 60-70 ℃, and then cooling to 30-40 ℃ to prepare a prehydrolysis solution;
(5) Adding the bird droppings Dan Chaoxi particles prepared in the step (3) into the prehydrolysis solution prepared in the step (4), and placing the bird droppings Dan Chaoxi particles in a penetrating type ultrasonic dispersing machine for ultrasonic dispersion to obtain a suspension; then stirring uniformly by using a cantilever stirrer to obtain emulsion, thereby modifying the bird droppings Dan Chaoxi particles:
(6) Drying the emulsion obtained in the step (5) in a vacuum freeze dryer for 18-30h to obtain modified guano Dan Chaoxi particles;
(7) Adding the modified guano Dan Chaoxi particles obtained in the step (6) into a rotor mill for drying, scattering and modifying, and reducing the agglomerated dry powder particles to the original particle size; then adding silicone oil, hydrophobic nano silicon dioxide, talcum powder and magnesium stearate to carry out dry powder modification; heating to 30-40 ℃ and drying for 8-16 hours to obtain modified bird dung Dan Chaoxi dry powder;
in the step (1), the supernatant fluid of the sewage treatment plant is a phosphorus-rich solution containing urban domestic sewage or farm sewage; the porous solid substance is at least one of porous adsorption materials including activated carbon, chitosan resin, acidified sepiolite and aluminum zirconium pillared montmorillonite;
the magnesium orthosalt is at least one of magnesium chloride, magnesium nitrate and magnesium sulfate; the ammonium salt of normal water is at least one selected from ammonium chloride, ammonium sulfate and ammonium fluoride;
in step (4), the organic surface modifier is selected from phosphorus-containing silicone DOPO-VTS.
2. The method for preparing the modified guano Dan Chaoxi dry powder according to claim 1, which is characterized in that: in the step (2), the alkali liquor is selected from at least one of ammonia water, potassium hydroxide and sodium hydroxide aqueous solution; the stirring speed is 500-900rpm, and the stirring time is 20-40min.
3. The method for preparing the modified guano Dan Chaoxi dry powder according to claim 1, which is characterized in that: in the step (3), the rotating speed of the air classifying mill is 3000-4000rpm, and the treatment air quantity is 400-600m/h.
4. The method for preparing the modified guano Dan Chaoxi dry powder according to claim 1, which is characterized in that: in the step (5), the mass ratio of the guano Dan Chaoxi particles to the ethanol solution in the prehydrolysis solution is 1-2.5:5, a step of; the mass ratio of the organic surface modifier to the struvite ultrafine particles in the prehydrolysis solution is 3-5:100; the working power of the penetrating ultrasonic dispersion machine is 150-250w, the total working time is 15-25min, the single working time is 5-10s, and the working gap is 8-12s; the rotation speed of the cantilever stirrer is 400-800rpm, and the stirring time is 4-6h.
5. The method for preparing the modified guano Dan Chaoxi dry powder according to claim 1, which is characterized in that: in the step (7), the mass ratio of the modified struvite ultrafine particles to the silicone oil to the hydrophobic nano silicon dioxide to the talcum powder to the magnesium stearate is 100:1-1.5:4-6:1.5-2.5:1.5-2.5; reducing the agglomerated dry powder particles to the original particle size, wherein the rotating speed of a rotor mill is 800-1200rpm, and the treatment time is 20-30min; the rotating speed of the rotor mill is 1500-1700rpm during dry powder modification, and the treatment time is 1.5-3h.
6. The method for preparing the modified guano Dan Chaoxi dry powder according to claim 5, which is characterized in that: the particle size of the hydrophobic nano silicon dioxide is 15nm, and the comparison area is 300+/-50 square meters per gram.
CN202210882495.XA 2022-07-26 2022-07-26 Preparation method of modified guano Dan Chaoxi dry powder Active CN115477857B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210882495.XA CN115477857B (en) 2022-07-26 2022-07-26 Preparation method of modified guano Dan Chaoxi dry powder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210882495.XA CN115477857B (en) 2022-07-26 2022-07-26 Preparation method of modified guano Dan Chaoxi dry powder

Publications (2)

Publication Number Publication Date
CN115477857A CN115477857A (en) 2022-12-16
CN115477857B true CN115477857B (en) 2023-08-08

Family

ID=84422539

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210882495.XA Active CN115477857B (en) 2022-07-26 2022-07-26 Preparation method of modified guano Dan Chaoxi dry powder

Country Status (1)

Country Link
CN (1) CN115477857B (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102949798A (en) * 2011-08-16 2013-03-06 陕西坚瑞消防股份有限公司 Novel fire-extinguishing composition
CN112245855A (en) * 2020-10-28 2021-01-22 东北大学 Method and device for preparing dry powder extinguishing agent by using waste water from zeolite treatment synthesized from fly ash
CN113827906A (en) * 2021-11-08 2021-12-24 中国民航大学 Preparation method of dry powder extinguishing agent containing allophanate salt
CN114753160A (en) * 2022-03-21 2022-07-15 南方科技大学 Anti-ultraviolet flame retardant, preparation method thereof, anti-ultraviolet flame-retardant composition and product

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10479728B2 (en) * 2013-08-12 2019-11-19 Certainteed Gypsum, Inc. Struvite-K and Syngenite composition for use in building materials

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102949798A (en) * 2011-08-16 2013-03-06 陕西坚瑞消防股份有限公司 Novel fire-extinguishing composition
CN112245855A (en) * 2020-10-28 2021-01-22 东北大学 Method and device for preparing dry powder extinguishing agent by using waste water from zeolite treatment synthesized from fly ash
CN113827906A (en) * 2021-11-08 2021-12-24 中国民航大学 Preparation method of dry powder extinguishing agent containing allophanate salt
CN114753160A (en) * 2022-03-21 2022-07-15 南方科技大学 Anti-ultraviolet flame retardant, preparation method thereof, anti-ultraviolet flame-retardant composition and product

Also Published As

Publication number Publication date
CN115477857A (en) 2022-12-16

Similar Documents

Publication Publication Date Title
CN104147890B (en) Utilize attapulgite clay suspension to reunite and trap coal-fired PM 2.5method
WO2019237482A1 (en) Efficient and environmentally-friendly fire extinguishing agent and preparation method therefor
CN101239228A (en) Ammonium phosphate ultra-fine dry powder extinguishing agent and preparation thereof
RU2280677C2 (en) Method of reduction of sulfur dioxide emissions during burning of coals
CN101622196A (en) Handle the method for contaminated by heavy metals material
CN107096350A (en) It is a kind of to cooperate with the chemical agglomeration promotor and method for removing coal-fired flue-gas pollutant
JP2011177711A (en) Method of treating gas
AU2002254490A1 (en) Reducing sulfur dioxide emissions from coal combustion
CN115477857B (en) Preparation method of modified guano Dan Chaoxi dry powder
Fan et al. Study on magnesium slag desulfurizer modified by additives in quenching hydration
CN101747534B (en) Method for preparing thermostable nano hydrotalcite used in PVC resin
CN1284729C (en) Method for preparing superfine light calcium carbonate
CN109973136B (en) Composite explosion suppressant for suppressing low-concentration coal bed gas explosion and preparation method thereof
CN103588231A (en) Magnesium sulfate preparation method
KR20110023033A (en) Preparation of ash-free coal including desulfurization
Liang et al. Preparation and fire extinguishing mechanism of novel fire extinguishing powder based on recyclable struvite
CN110566264A (en) Superfine montmorillonite-based core-shell structure explosion suppressant and preparation method thereof
BE1025977B1 (en) SORBENT COMPOSITION FOR AN ELECTROSTATIC PRECIPITATOR
Dhanke et al. Phosphate removal from industrial wastewater effluent using modified coal fly ash
CN115159487A (en) Method for preparing ammonium polyphosphate by using waste dry powder extinguishing agent
CN111453749B (en) Production process and application of magnesium hydroxide suspension with high solid content
JPH044015B2 (en)
CN111807393A (en) Method for improving compatibility of aluminum hydroxide
JP2002035548A (en) Gas treatment method
JP6183441B2 (en) Acid gas treating agent and acid gas treating method

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant