1033 results about "Calcium formate" patented technology

The invention discloses a concrete early-strength agent, which is characterized in comprising the following components according to weight percentage: inorganic salt early-strength component 35-55 percent, organic early-strength component 5-10 percent, water reducing component 15-25 percent, wherein the inorganic salt early-strength component is prepared by at least two among sulfate, carbonate, nitrate, and nitrite; the organic early-strength component selects any one among calcium formate, sodium acetate, calcium oxalate, triethanolamine, tri-iso-propanolamine and carbamide; the water reducing component selects one among naphthalenesulfuric acid type, melamine type and polycarboxylate type. The invention makes the concrete be coagulated and hardened rapidly under the condition of low temperature, so that the early strength of the concrete is greatly improved as well as later strength is ensured.

The invention discloses a liquid alkali-free chloride-free accelerating agent and methods for preparing and using the same. Raw materials for preparing the accelerating agent include one or a plurality of the following components of aluminum sulfate, magnesium sulfate, hydramine, an early strength agent, a synergist and water. The aluminum sulfate is the purchasable industrial-grade aluminum sulfate hydrate Al2(SO4)3.18H2O and has the solid content of 51%-52%. The magnesium sulfate is MgSO4.7H2O with the solid content of 48%-49%. The hydramine is one or a plurality of mono ethanol amine, diethanolamine, triethanolamine or isopropoxide. The early strength agent is one or a plurality of calcium sulfate, calcium formate or calcium nitrite. The synergist is magnesium fluosilicate and / or magnesium fluoride. The liquid alkali-free chloride-free accelerating agent provided by the invention has the characteristics of good adaptability, low price, low mixing amount, good performance, good stability and the like; and moreover, the liquid alkali-free chloride-free accelerating agent is added into the concrete to be used as sprayed concrete, has the characteristics of low resilience, small dust pollution and the like and can satisfy the requirements of the 'JC477-2005 sprayed concrete accelerating agent' standard.

The invention relates to an unsteamed concrete air-filled insulating brick produced from building waste, and a production method of the insulating brick. The insulating brick is prepared from the raw materials in parts by weight: 30-40 parts of cement, 20-30 parts of aggregate, 8-10 parts of CaO, 3-5 parts of CaSO4, 3-5 parts of carbamide, 3-5 parts of polyvinyl alcohol, 5-10 parts of cellulose hydroxypropyl methyl, 3-5 parts of calcium formate, 5-10 parts of foaming agent and 40-60 parts of external water, wherein cement contains one or more than two of common silicate, high-alumina cement, fly ash cement, alumina cement and aluminate cement; the aggregate is building waste with the particle size being less than or equal to 5mm; and the foaming agent contains one or more than two of aluminium powder, aluminium powder paste, hydrogen peroxide and sodium hydrogen carbonate. The unsteamedconcrete insulating brick is prepared by material preparing, mixing, injection molding and curing. Therefore, the land occupation and the living environmental pollution caused by the building waste can be effectively reduced, and the produced unsteamed concrete air-filled insulating brick has the advantages of good heat insulation effect, light weight, good sound insulation effect and high strength, and can be nailed and sawed; and the construction intensity can be reduced.

The invention relates to an admixture for high early strength of concrete, characterized in that the admixture is formed by mixing and stirring cement clinkers, industrial residues, early strength agents, plaster, water reducing agents and excitants. The parts by weight of the components are as follows: 100 parts of cement clinkers, 500-2000 parts of industrial residues, 0.2-3 parts of early strength agents, 1-3 parts of plaster, 0.2-2 parts of water reducing agents and 1-5 parts of excitants. The excitant is the mixture of aluminum hydroxide, calcium nitrite and calcium nitrate; wherein, the aluminum hydroxide accounts for 50% of the mixture while the calcium nitrite and the calcium nitrate are in any proportion; the early strength agent is the mixture of trolamine, lithium carbonate and calcium formate, wherein, the trolamine accounts for 50% of the mixture while the lithium carbonate and the calcium formate are in any proportion. The admixture for concrete provided by the invention has high activity index and low content of harmful ions. Adding the admixture can obviously improve the demoulding strength, long-term mechanical property and durability of the concrete.

The invention relates to poly carboxylic acid system antifreeze applied to cement concrete and a preparation method thereof and belongs to the building material field. The antifreeze is prepared by the optimal combination of an efficient water reduce of poly carboxylic acid, organic alcohol amine, low-carbon alcohol, sulfocyanide and formate. The preferred proportion of the components is that the efficient water reducer to the organic alcohol amine to the low-carbon alcohol to the sulfocyanide to the calcium formate to water is equal to (3.0-8.0) to (0.5-2.0) to (0.0-2.0) to (10.0-20.0) to (0.0-6.0) to (65.0-75.0) (by mass percentage). Compared with the existing antifreeze, the antifreeze of the system has the advantages of high water reducing rate and comparatively good workability and quick growth of strength at negative temperature. The antifreeze has the advantages of low intermingled quantity in the cement concrete, good water solubility, low alkali content, high strength at the early stage and at the later stage of the cement concrete but no chlorine and is applicable to the preparation of various cement concrete at the negative temperature ranging from negative 5 DEG C to negative 20 DEG C in winter in the north area.

The invention discloses a liquid cement grinding aid. The liquid cement grinding aid comprises the following components by weight percent: 10-24% of triethanolamine, 10-16% of polymeric polyol, 10-13% of molasses, 1-3% of calcium formate, 3-5% of sodium acetate, 5-10% of sodium thiosulfate and the balance water. Compared with the prior art, the liquid cement grinding aid has the advantages that the grain composition of a cement material is changed, the strength of cement is improved, enhancing effect of the cement mixed with a large quantity of limestone is improved obviously; the cost is lower as the using amount of triethanolamine is reduced; the cement output in the unit time is increased effectively, and the power consumption of per unit output is reduced as the mixing amount in the cement finishing process is low; the liquid cement grinding aid is green and environmental-friendly and cannot hurt people, or cannot damage buildings and the like as chloridion content is not contained.

The invention relates to a fermented feed for nursery pigs and a preparation method thereof. The feed is prepared from the following raw materials in parts by weight through fermenting: 400-700 parts of corns, 50-200 parts of soybean meal, 2-6 pats of lysine hydrochloride, 1-10 parts of calcium formate, 1-10 parts of calcium hydrogen phosphate, 0.2-0.5 part of vitamin premix, 2.5-3.5 parts of organic microelement premix, 1-5 parts of micro-ecologic, 0.2-2 parts of complex enzyme preparation and 0.5-2.0 parts of sodium butyrate. With the consideration of improving the digestion utilization rate of the feed for nursery pigs, together with the physiological characteristics of the nursery pigs, directing to the problems in the existing nursery pig feed processing technology, and through introducing the fermentation technology to prepare the feed and adjusting the structure of daily grains, the plant raw material digestion utilization rate is improved, the feed cost is reduced; in the preparation and production of the feed for the stage, the purposes of reducing energy consumption, reducing cost and improving intestinal health of animals and improving the growth rate are realized.

The present invention discloses a fiber reinforcement fire-proof thermal insulation plate, which is prepared by raw materials having the following weight portions: 80-100 portions of fly ash, 30-50 portions of expanded perlite, 10-20 portions of haydite, 10-20 portions of vegetable fiber, 5-10 portions of winnowing beads, 5-8 portions of sepiolite, 3-5 portions of sodium fluorosilicate, 3-5 portions of calcium formate, 3-5 portions of flame-retardant, 0.1-0.5 portion of triisopropanolamine loeate and 0.1-0.3 portion of dimethoxy-ethane. According to the present invention, industrial production wastes are adopted as main raw materials, so that the production cost is reduced; and defects in the existing building thermal insulation plates can be effectively overcome through the cooperation effect produced by organic combination of the fly ash, light aggregates and additives.

The invention provides a high-strength micro-expansive grouting material and its preparation method. Raw materials of the high-strength micro-expansive grouting material comprise Portland cement having a compressive strength of above 42.5MPa, sulphoaluminate cement or aluminous cement having a compressive strength of above 42.5MPa, a calcium sulphoaluminate expanding agent, quartz sand or corundum or iron tailings, an organic silicon antifoaming agent, a polycarboxylate superplasticizer, calcium formate or lithium carbonate, sodium gluconate, and methyl cellulose ether or hydroxypropyl methyl cellulose ether or hydroxyethyl methyl cellulose ether. Compared with present cement-based grouting materials treating the sulphoaluminate cement and the aluminous cement as main cementing materials, the high-strength micro-expansive grouting material, which is obtained through treating the Portland cement as a main cementing material component, carrying out ultrafine crushing of the cementing material component via an ultrafine crushing technology, and processing, has the characteristics of high early-stage strength, excellent fluidity, increased long-term strength, and good durability; and compared with traditional epoxy mortars, the high-strength micro-expansive grouting material has the characteristics of micro-expansion, simple and fast construction, non-toxicity, and harmlessness.

The invention discloses an anti-freeze aerated concrete brick. The anti-freeze aerated concrete brick is prepared from the following raw materials in parts by weight: 35-40 parts of fly ash, 15-20 parts of cement, 15-20 parts of wollastonite powder, 5-10 parts of modified straw ash, 2-4 parts of gypsum, 0.05-0.1 part of aluminum powder, 2-4 parts of urea, 0.01-0.03 part of oxyparaffin soap, 1-2 parts of sugar calcium, 4-6 parts of calcium formate, 0.1-0.5 part of polyethylene wax powder, 4-6 parts of calcium carbonate, 0.2-0.4 part of calcium nitrate, 0.1-0.2 part of sodium acetate and right amount of water.

The invention discloses a cement grinding aid, comprising calcium formate solution, compound glycerol distilled residue solution, triethanolamine, diols and molasses. While the product reutilizes the industrial wastes, the components of the product synergistically act to optimize the efficacy of the grinding process and the product modifies the cement particles, thus improving the quality and performance of the cement while improving the cement yield and saving electricity, and the product does not only have grinding function.

The invention provides a white surface mortar compound which comprises the following components of parts by weight: 400 to 600pbw of white cement, 50 to 100pbw of semi-water gypsum, 50 to 100pbw of calcium hydroxide, 200 to 400pbw of modified fiber light calcium, 30 to 50pbw of latex powder which can be dispersed again, 2 to 4pbw of cellulose ether, 1 to 3pbw calcium chloride, 1 to 3pbw of calcium formate, 1 to 3pbw of aluminum potassium sulfate, 1 to 5pbw of polypropylene fiber and 250pbw of water. The surface mortar compound of the invention can be hydrated with cement and other components to form fine, dense and good finish surface to be applied for painting a wall body with different color surfaces, and the cost is reduced while the construction efficiency is enhanced. The compound is particularly applicable to an insulation system of the external wall of a civil building and an office building, which is economic and can be used as the surface mortar and internal dope of other wall bodies.

The invention belongs to the building material technique field, in particular relates to a building thermal insulating mortar. The building thermal insulating mortar is characterized in that the mortar is composed of dry powder and water, the dry powder and water are present in a weight ratio of 1:1.3, when in use, the dry powder is added to the water and agitated evenly; and the dry powder is mixed by materials of modified cement, modified fly ashes, a re-dispersible latex powder, wood fibers, polypropylene fibers, calcium formate, hydroxypropyl methylcellulose, hydrophobic agent, multi-functional auxiliary agent and modified expanded perlite, materials of the dry powder include: 500 parts of modified cement, 160 parts of modified fly ashes, 25 parts of re-dispersible latex powder, 3 parts of wood fibers, 1 part of polypropylene fiber, 5 parts of calcium formate, 6 parts of hydroxypropyl methylcellulose, 1 part of hydrophobic agent, 3 parts of multi-functional auxiliary agent and 300 parts of modified expanded perlite by weight. The building thermal insulating mortar has advantages of strong heat preservation, firm bonding with wall bodies, compression resistance, superior tensile performance, good weathering resistance, environmental protection, and excellent waterproofing, anti-cracking and shedding prevention properties.

The invention discloses a concrete nano water-reducing super high-early-strength agent which is capable of remarkably increasing early and late strength of concrete and shortening construction period and simultaneously has good water-reducing performance, plastic retaining performance, corrosion inhibiting performance and stability. The agent comprises the following ingredients: 46-52 wt% of early strength components, 26-32 wt% of water reducing components, 6-15 wt% of corrosion inhibiting components, 4-5 wt% of retarding components, and 6-8 wt% of adjustment components, wherein the early strength components comprise three or four selected from magnesium sulfate, sodium sulfate, sodium nitrite, triethanolamine, sodium thiosulfate, triisopropanolamine, and calcium formate, the water reducing components comprise one selected from naphthalene sulfonic acid high-efficiency water reducer and carboxylic acid water reducer, the corrosion inhibiting components comprise one selected from calcium nitrite, calcium nitrate, potassium chromate, and stannous chloride, the retarding components comprise one selected from sodium gluconate and citric acid, and the adjustment components comprise nano ground calcium carbonate.

The invention provides an early-strength water reducer for recycled aggregate concrete, which is suitable for the field of building materials. The the early-strength water reducer comprises the following raw materials by weight percent: 20-25% of a polycarboxylic acid water reducer, 1-6% of tri-isopropanolamine, 0.5-2% of triethanolamine, 5-15% of sodium sulfocyanate, 3-10% of calcium formate, and 42-70.5% of water. The early-strength water reducer provided by the invention is low in dosage, good in early-strength effect, free from chloride ions, resistant to the corrosion of steel bars, suitable for recycled concrete, and capable of enhancing the early strength of a recycled concrete product and improving the peaceability of a recycled concrete mixture.

The invention discloses a pig intestine nursing healthcare type compound feed and a preparation method thereof. The feed is prepared by the following components of corn, expanded bean pulp, expanded soybean flour, fermented bean pulp, white fish meal, flour, soybean oil, soybean lecithin oil, expanded corn, zeolite powder, calcium hydrophosphate, calcium formate, choline chloride, salt, sucking pig compound premix, acidifier, lysine, methionine, threonine, tryptophan, zinc oxide, medicated premix, monosodium glutamate, Taiweimei, montmorillonite and phytase. The feed is capable of satisfying all the nutritional requirements of the nursed pigs and has high feed conversion rate. According to the feed, the weaning stress of the nursed pigs is considered, the slow-release creep feed is linked and the intestine healthcare problem of the nursed pigs is emphasized; and an intestine adjusting feed additive is selected, so that the diarrhea rate of the sucking pigs is reduced by 50-80%, the pig body structures can be improved at the same time, the pig skeletons are stretched and a foundation is laid for the rapid fattening of the pigs.

The present invention discloses a method for recycling and processing epoxy-ester sewage, relating to a technical method that resources are reclaimed from industrial wastewater to produce chemical products. The technical proposal of the invention is: formic acid sewage generated during the process of epoxy-ester production is treated by oil separating, and then formic acid solution is achieved by reaction with calcium carbonate; and the formic acid solution is further neutralized with calcium carbonate for a plurality of times after sedimentation; coagulant and precipitator are added into the solution to further remove heavy metal and solid impurities, and then is filtered, decolored, evaporated and dried to achieve formic acid powder. The process is applicable to the production of fodder-grade, industrial-grade and other grades of formic acids; besides, the process is characterized in less investment and high yield; and in addition, byproducts such as waste gas and waste water can be reclaimed for reuse. As a result, the reduction of waste water is realized and economic efficiency is improved.

The invention discloses feed for preventing diarrhea of weaning piglets. The feed consists of the following components in parts by weight: 200-300 parts of corn flour, 200-300 parts of rice meal, 100-180 parts of expanded soybean meal, 30-50 parts of fish meal, 220-270 parts of soybean meal, 80-120 parts of whey powder, 80-120 parts of glucose, 50-100 parts of serum concentrate, 20-45 parts of soybean oil, 20-45 parts of calcium hydrogen phosphate, 30-60 parts of calcium formate, 5-15 parts of lysine, 1-3 parts of methionine, 3-6 parts of threonine, 5-10 parts of compound trace elements, 1-2 parts of compound vitamin, 1-2 parts of probiotics, 10-20 parts of short chain fatty acids, 5-8 parts of organic compound acid, 0.5-1 part of enzyme preparation and 1-2 parts of phagostimulant. The feed provided by the invention can be used for effectively avoiding the negative growth of the weight of piglets, reducing the mortality rate of piglets subjected to weaning and the incidence of disease (diarrhea), realizing the rapid growth of the piglets, and obviously shortening the production cycle of the piglets.

The invention relates to a feed additive capable of improving irritability resistance of weaning piglets, as well as preparation and application of the feed additive. The feed additive comprises a composite active ingredient and carrier matrixes, wherein the composite active ingredient comprises the following components in parts by weight: 80-110 parts of glutamine, 30-50 parts of arginine, 40-60 parts of taurine, 80-100 parts of yeast nucleotide, 10-30 parts of vitamin B6, 30-60 parts of vitamin E, 30-60 parts of vitamin C, 10-30 parts of selenium yeast, 50-90 parts of calcium formate, 80-110 parts of sodium butyrate and 80-130 parts of citric acid; during preparation, the components and the carrier matrixes are uniformly mixed; when the feed additive is applied, on the basis of a daily feed formula for piglets, the feed additive, accounting for 0.5-2% of the total mass of the daily feed, is added. Compared with the prior art, the feed additive is capable of reducing adverse impact of irritability on follow-on production property and intestinal health of weaning piglets, improving daily gain and feed conversion rate of weaning piglets, reducing diarrhea rate and death rate of weaning piglets and strengthening adaptive capacity of weaning piglet to a new environment.

The invention discloses an antibiotic-free feed for nursery pigs and a preparation method thereof. Corn, barley and soybean meal are pre-cleaned to remove impurities and enter a permanent magnet drum to remove tramp iron; the materials enter a bin for smashing respectively; smashing is performed, 100% of smashed materials are subjected to 14-mesh sieving, and 95% of the smashed materials are subjected to 20-mesh sieving; suckling pig compound enzyme, a vitamin premixing agent, a microbial ecological agent, plant essential oil, phagostimulant, high temperature resistant phytase, an organic microelement premixing agent, a Chinese herbal medicine prescription, yeast cell wall polysaccharide, glycerol monobutyralte and an emulsifier are firstly mixed fully for use; then the corn, the barley, the soybean meal, soybean oil, extruded soybeans, fermented soybean meal, import fish meal, whey mist, salt, calcium formate, calcium hydrophosphate, amino acid, composite organic acid, an antioxidant and a mildewproof agent are weighed in proportion and then are compounded and mixed; finally granulation is performed. An antibiosis growth promotion effect which is the same as or better than that obtained by using antibiotics can be achieved, the sensibility of germs to the antibiotics is improved, and the treatment drug effect is improved.

The invention discloses feed for improving the immunity of weaning piglets. The feed consists of the following components in parts by weight: 100-200 parts of corn flour, 150-180 parts of rice meal, 150-200 parts of flour, 100-180 parts of expanded soybean meal, 30-50 parts of fish meal, 120-150 parts of soybean meal, 80-120 parts of soybean concentrate, 80-120 parts of whey powder, 80-120 parts of glucose, 50-100 parts of serum concentrate, 20-45 parts of soybean oil, 20-45 parts of calcium hydrogen phosphate, 30-60 parts of calcium formate, 5-15 parts of lysine, 1-3 parts of methionine, 3-6 parts of threonine, 5-10 parts of compound trace elements, 1-2 parts of compound vitamin, 1-2 parts of probiotics, 10-20 parts of short chain fatty acids, 5-8 parts of organic compound acid, 0.5-1 part of enzyme preparation and 1-2 parts of plant extracts. The feed provided by the invention can be used for improving the sub-health status generated in the weaning process, avoiding the negative growth of the weight of piglets, reducing the mortality and incidence of diseases, and realizing the rapid growth of weaning piglets.

The invention belongs to the technical field of building materials, in particular relates to acrylic ester emulsion modified cement base rapid repair mortar. The mortar consists of sulphoaluminate cement, desulfurated gypsum, quartz sand, an acrylate emulsion, a water reducer, polypropylene fiber, calcium formate, a defoamer and water. The problems that the traditional inorganic repair mortar is low in adhesion strength, is large in shrinkage, is easy to fall out, and the like are solved through using the mortar provided in the invention, thereby overcoming the defects that the compatibility of organic repair material and cement base material is poor, cost is high, and the like. By using the mortar in the invention, the problems of slow setting time, low early strength and large shrinkage of polymer modified cement base repair mortar are solved. The mortar in the invention has the advantages of high early strength, especially high breaking strength, stable later strength development and good flexibility and crack resistance, and is suitable for rapid repair of various cement base materials.

The invention relates to fireproof paint, in particular to tunnel fireproof paint, which is prepared from the following ingredients: a major bonding agent (ordinary Portland cement), inorganic heat insulation filling materials (expanded perlite, expanded vermiculite, meerschaum, kaoline and wollastonite powder) and addition agents (calcium formate, starch ether, redispersible latex powder, methyl cellulose ether and polypropylene fiber). Through the unique addition agent combination and the prescription mixture ratio, the tunnel fireproof paint has the advantages that the construction performance is obviously improved, at the same time, the integral overall performance of the tunnel fireproof paint is greatly improved, and the tunnel fireproof paint has the characteristics of stable fireproof performance, high adhesion intensity and stable physicochemical performance. Simultaneously, the product per se generates no toxic substance in the construction and burning processes, has the effects of environment protection and high practicability, and can be widely used for the fireproof protection of buildings such as highways, railways, subway tunnels and the like.

The invention discloses a cement concrete antifreezer, which comprises the following components in part by weight: 15 to 30 parts of high-performance polycarboxylate water reducer, 20 to 30 parts of low molecular weight alcohol, 0.1 to 0.15 part of triterpenoid saponins, 10 to 30 parts of calcium formate, 2 to 5 parts of organic alkylol amine and 50 to 70 parts of water, wherein the triterpenoid saponins is used for entraining air to form a large number of superfine air bubbles and improve the frost heaving stress of concrete. By the cement concrete antifreezer, the concrete can be subjected to construction at the temperature of between -20 and -30 DEG C.

The invention relates to a thermal insulation textured decorative face brick for a building outside wall. The face brick comprises the following raw materials in parts by weight: 25-35 parts of cement, 20-35 parts of quartz sand, 10-15 parts of calcite powder, 10-20 parts of wollastonite powder, 2.0-4.0 parts of latex powder, 0.3-0.4 part of hydroxypropyl cellulose, 0.5-1.0 part of wood fiber, 0.15-0.2 part of short polypropylene fiber, 0.2-0.5 part of calcium formate, 10-20 parts of gray calcium powder, 0.1-0.15 part of thixotropic lubricating agent and 0.25-0.5 part of pigment. After being put on the market, the face brick has great market space, and the current monotonous situation of outside wall exterior thermal insulation textured decorative materials can be improved, thus the face brick has active effects on saving energy of buildings and beautifying the environment of cities.

The invention discloses waterproof high polymer easy plaster, and belongs to the technical field of building materials. Based on the percentage, the waterproof high polymer easy plaster comprises the following raw materials: 40-50 percent of ordinary Portland cement, 30-45 percent of 60-120-mesh quartz sand, 5-20 percent of 40-70-mesh quartz sand, 1.5-3.0 percent of redispersible latex powder, 0.2-0.35 percent of hydroxypropyl methyl cellulose, 0.4-0.8 percent of calcium formate, 0.05-0.15 percent of starch ether, 0.2-0.4 percent of hydrophobing agent, and 0.07-0.12 percent of polypropylene fiber. In general, the waterproof high polymer easy plaster is high in bonding strength, is greatly advantaged in waterproof performance in comparison with the previous easy plaster, and meets the social requirement.

The invention discloses a foamed cement heat insulation board and a preparation method thereof. The foamed cement heat insulation board comprises the components in parts by weight: 100-180 parts of ordinary portland cement, 40-90 parts of pulverized fuel ash, 2-5 parts of waterproofing agent, 0.04-0.09 part of calcium formate, 4-9 parts of activated silica, 0.5-1 part of fiber and 10-18 parts of foaming agent. The foamed cement heat insulation material disclosed by the invention is a non-combustible material, has the fireproof flame retardant standard reaching to level A, and is non-toxic, odorless and free from environmental pollution, thus being an energy-saving and environment-friendly material; and the foamed cement heat insulation board made of the foamed cement heat insulation material is long in service life which is equal to that of a building, thus being the best energy-saving material in the current building energy conservation market. Meanwhile, the foamed cement heat insulation board is good in waterproof effect and long in waterproof time, and has the waterproof service life equal to that of the building.

The invention relates to a method for coproducing high-purity methanoic acid and monobasic sodium phosphate by reaction of calcium formate and ultraphosphate. The method comprises the following steps that: carbon monoxide enters a reaction tower III; calcium hydroxide enters a reaction tower I to perform a counterflow reaction with carbon monoxide from a reaction tower II, a reaction solution overflows to the reaction tower II to perform the counterflow reaction with the carbon monoxide from the reaction tower III, the reaction solution enters the reaction tower III to perform the couterflow reaction with the carbon monoxide, the reaction solution overflows into a discharge tank from the reaction tower III to prepare a calcium formate preparation solution; the calcium formate preparation solution enters a reaction kettle, methanoic acid is dripped into the reaction kettle, sulfureted hydrogen is introduced into the reaction kettle, the mixture is separated and filtered through a filter I, a filtrate enters a continuous crystallizer, a crystalline liquid enters a filter II, and the filtered calcium formate is prepared into a finished product calcium formate through a drier; ultraphosphate, the methanoic acid and the calcium formate are conveyed into a horizontal double screw reactor to generate the methanoic acid and monobasic calcium phosphate; the methanoic acid and the monobasic calcium phosphate enter a methanoic acid distilling still for reduced pressure distillation; and the monobasic calcium phosphate is delivered to a monobasic calcium phosphate measurement receiving tank, while the monobasic acid enters a methanoic acid receiving tank. The method has high yield of the methanoic acid and low manufacturing cost.

The invention discloses a composite admixture for concrete, which is prepared from fly ash, siliceous dust, granulated blast-furnace slag, anhydrous sodium sulphate, hydroxypropyl methyl cellulose, UEA (united expansive agent), polycarboxylic acid water reducing agent, citric acid, boric acid, sodium gluconate, sodium phosphate, sodium tartrate, calcium carbona, lithium carbonate, calcium formate, calcium acetate and cellulose ether. In the practical application of the composite admixture, the strength of concrete is improved, the concrete workability is good, slight bleeding is caused, the use amount of cement is lowered, the unit volume water consumption is lowered, the working performances of the concrete are improved effectively, and the heat of hydration is reduced.