178results about How to "Prevent secondary combustion" patented technology

The invention relates to a steelmaking process control device for a steel making factory, in particular to a soft sealing device for an LD (linz-donawitz) converter mouth and fume hood. The periphery of the inlet of the fume hood is provided with a ring pipe; the ring pipe is provided with a nitrogen inlet pipe; and a plurality of nitrogen spraying nozzles are annularly distributed on the ring pipe at intervals. During each period of production of a converter, a nitrogen sealing curtain is formed between the inside fume and the outside air of the fume hood, and the fume is separated from the outside air without contacting. Because the fume is separated from the outside air without contacting, the secondary combustion of a system is avoided, the hidden danger of explosion of a dedusting system is avoided, the calorific value of gas is improved, the rear dedusting fume is reduced, the purity and the yield of gas are improved, and water and electricity are saved. The soft sealing device for the LD converter mouth and fume hood can be used safely and reliably, and radically solves the problem on the sealing of the converter mouth and fume hood.

The invention relates to a flame retardant cyclo-bromoethyl trisilicate compound and a preparation method thereof. The structure of the compound is represented by a formula shown in a drawing. The preparation method comprises the steps of reacting silicon tetrachloride with bromoethanol of a mole which is equal to that of silicon tetrachloride in an organic solvent at the temperature below 20 DEG C, then, dropwise adding an organic solution of trishydroxyethyl isocyanurate of a mole which is 1 / 3 that of silicon tetrachloride, heating to the temperature of 75-85 DEG C after completing dripping, and reacting for 8-10 hours; then, dropwise adding bromoethanol of a mole which is 2-3 times that of silicon tetrachloride, and carrying out heat-preservation reaction for 7-9 hours at the temperature of 75-85 DEG C; then, adding an acid binding agent, and carrying out heat preservation for 1 hour while stirring; purifying, thereby obtaining the flame retardant cyclo-bromoethyl trisilicate. The compound disclosed by the invention has high flame retarding efficacy and is suitable for serving as a flame retardant for materials, such as polyvinyl chloride, polyurethane, epoxy resin, unsaturated resin and the like, and the preparation method is simple and is low in cost, so that the industrial production is easy to realize.

The invention discloses a cooling method for a hot gas dispersoid fire-extinguishing device. The method is applied to the hot gas dispersoid fire-extinguishing device. The hot gas dispersoid fire-extinguishing device comprises a box body (1); a reaction barrel (3) filled with a hot gas dispersoid generating medicament (2) is arranged in the box body (1); and one side of the box body (1) is provided with a gas outlet (4). The method comprises the following steps of: improving the structure of the hot gas dispersoid fire-extinguishing device to realize physical cooling; and improving components and ratio of a chemical agent to realize chemical cooling. By improving the structure of the hot gas dispersoid fire-extinguishing device and the formula of the cooling agent, the temperature of a gas dispersoid passing through a nozzle is effectively reduced and the cooling effect is ideal; moreover, the cooling method is nontoxic and harmless, and has excellent safety and social benefit.

The invention relates to a flame retardant tris(hydroxyethyl) isocyanurate trisilicate ethyl chloride compound and a preparation method thereof. The compound has a structure shown in the specification. The preparation method comprises the following steps: introducing ethylene oxide into an organic solution of the silicon tetrachloride at a temperature being below 0 DEG C and reacting for 1 hour at 30 DEG C, wherein the molar mass of the ethylene oxide is 2 times that of the silicon tetrachloride; dropwise adding an organic solution of tris(hydroxyethyl) isocyanurate and reacting for 7-10 hours at 70-85 DEG C, wherein the molar mass of the organic solution of tris(hydroxyethyl) isocyanurate is 1 / 3 that of the silicon tetrachloride; cooling to the temperature being below 30 DEG C, introducing the ethylene oxide and reacting for 3-6 hours at 35-50 DEG C, wherein the molar mass of the ethylene oxide is 1-1.5 times that of the silicon tetrachloride; performing purification to obtain the tris(hydroxyethyl) isocyanurate trisilicate ethyl chloride. The compound disclosed by the invention is suitable to be used as flame retardants of the materials such as polyvinyl chloride, polyurethane, epoxy resin and unsaturated resin, is high in synergistic flame retardant performance, simple in preparation process and low in cost, and can be put into industrial production easily.

The invention discloses a toughened halogen-free flame-retardant polylactic acid blending material which is prepared by melting and blending the following components in percentage by weight: 40-93 percent of polylactic acid, 1-40 percent of toughener, 5-30 percent of flame retardant, 0-30 percent of auxiliary flame retardant and 0.5-1 percent of antioxidant. Because the toughener is also introduced into the polylactic acid blending material on the basis of adding a halogen-free flame retardant, the material has excellent flame retardant performance and also markedly improves the toughness of the polylactic acid simultaneously, thereby not only enlarging the use range of the material, but also solving the two great problems of easy combustion and poor toughness of the polylactic acid simultaneously.

The invention relates to a fire retardant alkyl silicic acid trithio phosphonia trioxa bicyclo[2.2.2]octyl methyl ester compound and a preparation method thereof. A structural formula of the compound is as shown in the specification, wherein R refers to CH3, CH3CH2 or CH3CH2CH2. The preparation method includes: performing reaction of alkyl trimethoxy silane or alkyltrichlorosilane with 1-thiophosphonia-4-hydroxymethyl-2,6,7-trioxa bicyclo[2.2.2]octane, and purifying to obtain alkyl silicic acid tri-1-thiophosphonia-2,6,7-trioxa bicyclo[2.2.2]octyl-4-methyl ester. The fire retardant is high in fire retardation efficiency, great in charring effect and suitable for serving as a fire-retardant charring agent for polyesters, polyurethanes, epoxy resin, unsaturated polyester resin and the like, and technical simplicity in production, low cost and easiness for industrial production are realized.

The invention discloses a boiler starting method for preventing oxide skin generation of a 1,000 MW octagonal tangent circle boiler and a secondary combustion accident of a tail flue. Boiler warming is carried out before a combustor is put into operation, then, the combustor is put into operation, and the operation of the combustor is adopted according to the following operation principles that all large oil guns in an AB layer and part of large oil guns in a CD layer are put one by one, and when the outlet pressure of a boiler steam-water separator reaches 0.3 MPa, all micro oil guns in an A layer are put, and then a powder manufacturing system of the A layer is put into operation; and at the thermal state flushing and temperature rising and boosting stage, part of or all large oil guns quit one by one according to the pulverized coal combustion situation, and at the load rising stage, powder manufacturing systems are put into operation layer by layer according to the load situation. According to the method, the temperature rising rate of a heating surface of the boiler in the starting process can be controlled, and the good combustion effect of the pulverized coal in a hearth can be guaranteed; and generation of pipe oxide kin of the heating surface of the boiler is effectively prevented, and the purposes of preventing secondary combustion of the tail flue and the detonation accident of the hearth can be achieved.

The invention relates to a silicon, nitrogen and phosphorus efficient halogen-free flame retardant, a preparation method thereof and an application of the flame retardant, and further discloses a fireproof flame-retardant coating and a preparation method thereof. The preparation method includes the steps: adding epoxy siloxane, triglycidyl isocyanurate and aminoimidazole into a reaction container,and uniformly mixing raw materials; slowly dripping phosphoric acid, and heating mixture to reach the temperature of 60-70 DEG C to perform reaction for 3-5 hours to prepare the silicon, nitrogen andphosphorus efficient halogen-free flame retardant. The self-made flame retardant is applied to preparation of the fireproof flame-retardant coating. A structure of a design molecule of the efficientflame retardant integrates an acid source, a carbon source and an air source, formation of carbon can be facilitated in combustion, a compact silicon carbon layer is formed, secondary combustion caused by melt dripping of high-molecular materials in combustion is prevented, better flame resistance is provided for the high-molecular materials, water resistance and weather resistance of the coatingcannot be affected, high flame retardant efficiency can be formed in combustion, and the environments cannot be polluted as the flame retardant is free from halogen.

The invention belongs to the high molecular material modification technical field, and in particular relates to a preparation method of natural fiber / poly lactic acid composite material with fire-retarding performance. The preparation method comprises the following steps: the surface modification and the fire-retarding modification of natural fiber are completed to improve the interface combination degree and the fire-retarding performance between the natural fiber and a poly lactic acid matrix; and then, the modified natural fiber is combined with poly lactic acid and fire retardant, therebyobtaining natural fiber-reinforced poly lactic acid composite material with excellent fire-retarding performance, mechanical property and full biodegradation. The poly lactic acid composite material,which can pass the fire-retarding testing in accordance with the standards of Federal Aviation Administration (FAA) and UL94V-O grade testing, can be used in fields such as airplane, automobile and electronic industry, which have strict requirements on material fire-retarding performance and mechanical property.

The invention relates to a triazine macromolecular halogen-free flame-retardant char-forming agent compound and a preparation method thereof. The structure of the compound is as shown in the description, wherein n is larger than 1, X is alcohol amine, and Y is dialkylamine. The preparation method comprises the steps that under the stirring condition, an equimolar amount of alcohol amine is added into a solution of triglycidyl isocyanurate, the temperature is increased to a certain value, and heat preservation reaction is conducted for a period of time to enable the pH of the solution to range from 7 to 8; a certain molar of dialkylamine is added, the temperature is increased to a certain value, and heat preservation reaction is conducted for a period of time to enable the pH of the solution to range from 7 to 8; cooling is conducted, suction filtration (recycling of solvent), water washing, drying and smashing are conducted, and the triazine macromolecular flame-retardant char-forming agent product is obtained. The triazine macromolecular halogen-free flame-retardant char-forming agent is an excellent flame-retardant char-forming agent, has a char-forming anti-dropping effect, is good in compatibility with high molecular materials and excellent in processability and can be used as the flame-retardant char-forming agent of materials such as polyethylene (PE), polypropylene (PP) and silicone rubber; the raw materials of the char-forming agent are low in price and easy to obtain, the production cost is low, the equipment investment is low, the production technology is simple, and scale production is easy.

The invention relates to a process for preparing a polyvinyl chloride cable material, and the process comprises the following steps: 1, adding PVC resin with the degree of polymerization of 1300, SG3 type PVC resin, cyclohexane-1,2-dinonyl diformate, acetyl butyl octyl citrate and white carbon black into a high-speed kneading machine for high-speed kneading for 3 to 5 minutes to reach temperature of 90 to 100 DEG C; 2, performing low-speed kneading for 1 minute, simultaneously pouring antimony trioxide, zinc borate, a filler, aluminum hydroxide, a calcium zinc heat stabilizer, antioxidant 1010, a lubricant, processing modifier P551J, an inorganic silicate deodorant and white carbon black, then performing high-speed kneading for 6 minutes, and when the temperature reaches 120 DEG C, fully mixing evenly, pre plasticizing, and discharging; and 3, when in extrusion, screw temperature of double screws being 120 DEG C to 150 C. The process greatly improves the flame retardant property of the material, and the material has good carbon forming effect during combustion, so that secondary combustion and flame propagation of the material can be prevented.

The invention discloses a heat storage and heat exchange linked heating furnace and an operation method thereof. The heat storage and heat exchange linked heating furnace comprises a hearth, a steel tapping furnace door, a steel input furnace door, a flue ad a stepping beam mounted in the hearth. The hearth is divided into a first heating section, a second heating section and a third heating section along the side from the steel input furnace door to the steel tapping furnace door, a first flat flame burner is mounted at the position, on the first heating section, of the top of the hearth, andflame adjusting burners are mounted on the two sides of the position, on the first heating section, of the hearth. Heat storage type burners are mounted on the two sides of the position, on the thirdheating section, of the hearth. The horizontal height of the top of the position, of the first heating section, of the hearth is lower than that of the position, of the third heating section, of thehearth. The top of the position, on the second heating section, of the hearth is concaved downwards to form a U shape from the position, on the first heating section, of the top of the hearth to the position, on the third heating section, of the top of the hearth. According to the heat storage and heat exchange linked heating furnace and the operation method thereof, the problem of large heat storage type furnace pressure and secondary combustion in a coal gas burner is effectively relieved.

The invention relates to a polydimethyl silicate terephthalic diester polymer as a flame-retardant charring agent and a preparation method thereof. The structural formula of the polymer is shown in the description, and in the structural formula, n is equal to 20-50. The preparation method comprises the following steps: in the presence of triethylamine, enabling hydroquinone to react with equimolar dimethyl dihalide silane in an organic solvent, or enabling hydroquinone sodium to react with equimolar dimethyl dihalide silane in an organic solvent, and performing purification so as to obtain polydimethyl silicon acid terephthalic diester. The polydimethyl silicate terephthalic diester disclosed by the invention is high in molecular weight, is good in material compatibility, is not easy to separate out, is good in charring performance, and is suitable for being used as a flame-retardant charring agent of polyolefine, polyester, polyamide, an epoxy resin, an unsaturated resin and the like. The production technology is simple, the cost is low, and the industrialized production is easy to realize.

The invention relates to a tris[2-(dimethylthioPEPAoxysilyloxy)ethyl] isocyanurate compound and a preparation method thereof. The structure of the compound is shown in the following formula: the preparation method is: Dissolve tris(2-hydroxyethyl)isocyanurate in an organic solvent, add dimethyldihalosilane which is 3 times molar relative to tris(2-hydroxyethyl)isocyanurate, and heat up to 50°C ~70°C, keep warm for 5~9h; cool down to below 30°C, add a certain mole of SPEPA, heat up to 70°C~100°C, keep warm for 6~14h; after purification, tris[2‑(2 MethylthioPEPAoxysilyloxy)ethyl] ester. The flame retardant of the invention has high flame retardant efficiency and good char formation performance, is suitable for use as a flame retardant for polyolefin, polyester, epoxy resin, unsaturated resin, etc., has simple production process, low cost, and is easy to realize industrialized production.

The invention relates to a flame retardant tetra(tribromophenyl) silicate esterification compound and a preparation method thereof. The structure of the compound is shown in the specification. The preparation method comprises the following steps of: adding tribromophenol of quadruple molar weight into an organic solution of silicon tetrachloride at 30 DEG C; heating to 45 DEG C in one hour, and performing a thermal-insulation reaction for one hour; heating to 100-120 DEG C, and performing a thermal-insulation reaction for 8-12 hours; and performing reduced-pressure distillation to remove the solvent to obtain the product tetra(tribromophenyl) silicate. The tetra(tribromophenyl) silicate provided by the invention is an excellent flame-retardant plasticizer with a charring anti-drop effect and good compatibility with a high-molecular material, and can be used as a flame retardant for the materials such as polyvinyl chloride, unsaturated polyester, polyurethane, epoxy resin and the like; and moreover, the flame retardant has the advantages of cheap and easily-available raw materials, low equipment investment and simple production technology, and is easy to produce in a large scale.