412results about How to "Control moisture content" patented technology

A once-through high pressure steam generator and reheater configured to eliminate the majority of components limiting cyclical life of fast start conventional HRSGs. Two remaining problematic components in conventional designs the final superheater and reheater tubes overheat while their headers remain colder in fast starts. In this inventive HRSG the critical components are arranged and started by a method that limits these damaging temperature differentials. At ignition when exhaust gas surges into a wet superheater steam flow starts minutes before conventional systems. This early steam flow cools the tubes while heating the headers, thereby reducing life damaging stresses. Steam temperature is controlled through the start and warms the rest of the plant earlier without attemperators with their problematic thermal stress history. Faster starts than conventional result without damaging fatigue life depletion with this low cost innovation.

The invention provides a method for modifying cotton and long vegetable fiber or yarn by ammonia liquid, which comprises the following steps: firstly, drying pre-treatment of raw materials; secondly, ammonia leaching of the raw materials in a hermetical treatment tank; thirdly, spin-drying of the raw materials subjected to ammonia leaching when a creel is twirled; fourthly, drying of the raw materials subjected to spin-drying by ammonia flow when the creel rotates slowly; fifthly, flushing of the raw materials which are dried by the ammonia flow by airflow when the creel rotates slowly; and so on. The method keeps the inherent advantages of the cotton, the long vegetable fiber and the yarn, overcomes the defects of the cotton, the long vegetable fiber and the yarn, increases softness, crimp tendency and fluffiness of the cotton, the long vegetable fiber and the yarn, improves the dye-uptake rate, the leveling property and the showy dye level, and further solves the problems of energy conservation, efficiency improvement and environmental protection.

In the conventional process of producing a coated paper, the use of a furnish that is characterized by a base sheet fiber content made of about 60 to 85 weight percent of a bleached thermomechanical pulp (TMP), about 10 to 35 weight percent of a bleached chemical pulp and 0 to about 15 weight percent of a deinked pulp, and also comprising about 12 to 20 weight percent of an inorganic filler, with a freeness below 50 ml Csf and a brightness over 75° ISO, gives a coated paper of the same or superior quality and at a much lower cost than the usual coated paper obtained through a conventional process.

The invention provides a treatment method of manure waste generated in the process of soaking manure in water in a breeding farm, which comprises the following steps: (1) performing solid-liquid separation of the manure waste to form a solid substance and waste water; (2) adjusting the solid substance into a solid fermentable substance with a solid mass content of 6%-12%; (3) performing anaerobic fermentation of the solid fermentable substance to generate biogas residues, biogas liquid, and biogas; (4) performing waste water anaerobic fermentation of the waste water generated in step (1) and the biogas liquid generated in step (3) to generate biogas and fertilized water; (5) collecting the biogas generated in step (3) and step (4). The invention can increase the biogas yield by 15%-30%, and save the volume of the anaerobic reactor by 50%-80%; fertilizer production by biogas residues is performed after the solid substance in pig manure is anaerobically fermented, so the sterilization effect of the fertilizer is ensured; and the production process does not require changes of the breeding mode or control of the water content of pig manure.

The invention discloses a method for enhancing the taste of rice noodles by taking fresh rice as raw material. The method adopts a common production process of the rice noodles and comprises the following steps: soaking and smashing, then adding dietary fiber and rice protein in a certain ratio into the process of stirring, and adjusting water content; then performing processes of twin-screw extrusion, aging 1, steaming again, aging 2, washing and the like; finally, drying, cutting, sterilizing and packaging to obtain the rice noodles. In the rice noodles prepared by the method, the selection requirements of the raw materials are greatly reduced; various fresh early indica rice, late indica rice, mixed rice of early indica rice and late indica rice and broken rice are applicable. The rice noodles prepared by the method are less in pulp output amount and low in rice bar broken rate; meanwhile, the rice noodles have porous structures which are easily tasted and strong in reconstitution properties. In addition, the added dietary fiber and rice protein are capable of well making up the defect of relatively single nutrition of original rice noodles, so that the requirements of consumers on mouth feel, flavor and nutrition are met.

The invention relates to a paint-free decorative overlay fitment board, in particular to a formaldehyde purification inflaming retarding oriented strand board and a manufacturing method thereof, and belongs to the wood processing industry. The formaldehyde purification inflaming retarding oriented strand board comprises a base material layer, an upper surface layer decorative film adhesive layer and a lower surface layer decorative film adhesive layer. The upper surface layer decorative film adhesive layer and / or the lower surface layer decorative film adhesive layer are immersed with an amino resin adhesive solution and a formaldehyde decomposition adhesive solution, the base material layer is an oriented strand board layer, the oriented strand board layer comprises an upper surface layer, a lower surface layer and a core layer shaving layer, wherein the glue mixing wood shavings on the upper and lower surface layers are longitudinally arranged in the fiber direction, the glue mixing wood shavings on the core layer shaving layer are transversely arranged in the fiber direction, an inflaming retarding layer is arranged between the lower surface shaving layer and the core layer shaving layer, and an inflaming retarding layer is arranged between the upper surface shaving layer and the core layer shaving layer. The manufacturing method of the paint-free decorative overlay fitment board comprises the steps of base material sanding, formaldehyde decomposition adhesive solution preparation, decorative film adhesive manufacturing, assembling and pressing and sticking. The formaldehyde purification inflaming retarding oriented strand board is realistic in effect, low in cost and good in formaldehyde purification effect.

A method is disclosed which produces acrylic acid in a high yield as maintaining the conditions for purifying acrylic acid in constant ranges and preventing the acrylic acid from polymerization. By using a reactor which has first reaction zone and second reaction zone formed of different reaction tubes, propylene concentration adjusting in the range of 7–15 vol. % and water concentration adjusting in the range of 0–10 vol. % are introduced thereto thereby obtaining an acrylic acid-containing gas. Then the gas is introduced to an acrylic acid absorption column to adjust water concentration in the range of 1–45 wt. %, thereby preventing from polymerization.

The invention discloses a method for preparing fluoroethylene carbonate, which comprises the following steps: providing a mixture of a fluorating agent and a solvent; providing a chloroethylene carbonate raw material; heating the mixture, and dripping the chloroethylene carbonate into the mixture under a constant pressure when the mixture is heated to a required temperature; and performing distillation under reduced pressure on a reaction system during dripping or after dripping to obtain a coarse fluoroethylene carbonate product. When the preparation method of the invention is used, high-purity and low-moisture content product can be obtained in a shorter period.

The invention relates to a method used for recycling waste concrete and a device thereof. By adopting the method, the waste concrete is washed with water and separated by using a vibrating screen; the cementitious material is separated in seriflux state from sand stone mixture and then is precipitated and processed with negative pressure water absorption, thereby the water content of the cementitious material is controlled within any level of scheduled 30 to 50 percent; according to the selection of the concrete intensity grades, exceeding amount of different doped contents are used for replacing parts of the cement to produce the concrete, and the water contained in the seriflux of the cementitious material is deducted. The concrete of C25 grade and the grade below C25 replaces the cement in exceeding amount according to 10 to 20 percent of the cement quality, and the exceeding coefficient is 2.5 to 3.0; the concrete of C30 grade and the grade above C30 replaces cement in exceeding amount according to 5 to 10 percent of cement quality and the exceeding coefficient is 2.5 to 3.0; proper amount of retarder can be added into the seriflux of the cementitious material which can not be utilized within two hours to ensure the activity of the srifulux of the cementitious material; the separated water can be used for producing concrete or recycled for car-washing circularly; the separated sand and stone can be used as the raw material for producing concrete; the invention is ingeniously conceived, which realizes the purpose of thoroughly recycling the waste concrete with low investment and low cost, has tremendous economic benefit and plays an important role in environmental protection.

The invention discloses a drunken tilapia snack food and a processing method thereof. Tilapia fillets are prepared into semi-dried drunken fillets through the steps of picking, inebriating, vacuum microwave drying and the like. By controlling the drying conditions, the flavoring material and original chewiness of the drunken fish are well maintained while the water content of the drunken fish is improved, and thus the drunken fish is good in flavor and taste. The process is capable of shortening the production period, reducing the production cost, and facilitating production. The drunken tilapia snack food processed by the method disclosed by the invention is natural in flesh color, compact, fresh and tender in meat, proper in salt taste, hardness and moisture, free from intermuscular fishbone, and suitable for people of all ages. The method is further suitable for small and medium freshwater fish, such as colussoma brachypomum, without or with less intermuscular fishbone.

The invention discloses a method for maintaining porous concrete through carbon dioxide. The method includes the following steps: (1) concrete is mixed and formed; (2) an obtained initial concrete body is placed into a pre-maintenance device for pre-maintenance, wherein the pre-maintenance temperature ranges from 15 DEG C to 25 DEG C, and the relative humidity ranges from 50% to 70%; air circulates through an air blower or a fan, wherein the pre-maintenance time ranges from 1 h to 18 h; (3) when the residual water-cement ratio of the mixed material body obtained after pre-maintenance reaches a preset residual water-cement ratio, the mixed material body is placed into a CO2 maintenance container, vacuumizing is carried out, then CO2 gas is led into the CO2 maintenance container for CO2 maintenance, the gas is discharged after maintenance is completed, and maintenance is stopped. By means of the method, control over the moisture content of the concrete body can be achieved, the carbon dioxide gas absorption capacity of the concrete can be effectively improved, and the quality of a concrete product can be effectively improved; in addition, the waste greenhouse effect gas, namely the carbon dioxide gas can be effectively used, the emission of the greenhouse gas can be reduced, the environment can be protected, and the greenhouse effect can be suppressed.

The invention involves a high efficiency energy saving automatic system for producing roasted seeds and nuts, which includes cooking device, after being cooked by cooking device the product is lifted into dehydrator by lifting device, after dehydration the product is transferred into dryer through conveyor belt, entrance region of first layer conveyor belt in the dryer and last layer conveyor belt are equipped with infrared heater respectively, the top part of the dryer is equipped with humidity-discharging port, at least one layer of conveyor belt is installed in the dryer, the conveyor belt is driven by conveying roller and carrier roller belt, the upper part of the conveyor belt is installed with hot air injector, after being dried the product is cooled in cooler, after being cooled the product is separated in separator, at last the finished product is packed. The invention has merits of low energy consumption, low material consumption, high work efficiency, low producing cost and small occupation area.

The production process of shaddock flower scented tea includes tea blank treatment, collecting shaddock flower petal, mixing tea leaf and shaddock flower petal, fumigating, separating shaddock flower petal from tea leaf, drying, adding flower, packing and other steps. The said production process has controllable water content of tea in fumigating, and the tea product has pure fragrance of shaddock flower petal, lasting fragrance in tea product, and other features.

The invention discloses a method for preparing binary nanometer cooperative reinforcing and toughening silicon carbide ceramics, and silicon carbide powder, yttrium aluminum garnet, nano particles and nano crystal whickers are taken as the main raw materials. The method comprises the following steps: 1) the main raw materials, a binder and a dispersant are added into de-ionized water, after being ball-milled and mixed, water-base silicon carbide slurry is prepared; 2) the water-base silicon carbide slurry is sprayed and dried by adopting a spray granulation technology; 3) the obtained silicon carbide granulating powder is formed by adopting pre-pressing of dry pressing and final pressing of cold isostatic pressing; and 4) the obtained green body of silicon carbide is put in a vacuum non-pressure sintering furnace to be treated, thus obtaining the binary nanometer cooperative reinforcing and toughening silicon carbide ceramics. The invention also discloses the binary nanometer cooperative reinforcing and toughening silicon carbide ceramics prepared in the method. The silicon carbide ceramics have the advantages of large flexural strength, good fracture toughness and the like.

The invention provides a straw rubbing process, which comprises the following operating steps: 1) carding raw material straws, removing sundries, such as broken pieces and the like, and cutting fringe pulling ends away; 2) rolling the straws with a continuous roll squeezer; 3) softening the straws with vapor; 4) drying the straws and controlling water content; 5) rubbing the straws with a straw rubbing machine to obtain straw threads and removing dust during the rubbing process; and 6) screening the straw threads to extract the straw threads with lengths not less than 5cm and diameters of 1 to 3mm. The process has the advantages of simple operation, easy implementation, low cost, high efficiency, no pollution to the environment, relatively longer silky fibers and high mechanical strength, and is mainly used for manufacturing products, such as a vegetation carpet, a green pad and the like.

There is provided a natural alkaline earth metal carbonate having a d50 of about 0.5 μm or less and a moisture pick up of less than about 0.2 wt %, as well as a process for making the particulate carbonate by grinding. The carbonate may be used in polymer compositions.

The invention relates to a grain storage refrigeration house and a grain storage method, the grain storage refrigeration house comprises a grain storage bin body, a sealed grain storage refrigerationhouse is arranged in the grain storage bin body, grain is stored in the grain storage refrigeration house, and at least one set of air supply mechanism 6 is arranged at the bottom of the grain storagerefrigeration house; at least one set of air circulation device is arranged in the grain storage refrigeration house and used for pumping the air above the grain surface in the grain storage refrigeration house to the grain bottom for internal circulation; a controller controls operation of the air circulation device according to the received temperature of the a first temperature sensor; or thecontroller controls operation of the air circulation device according to the temperature difference of the first temperature sensor and a second temperature sensor. According to the grain storage method, air is conveyed in winter and used for internal circulation in next summer, the temperature difference of the grain surface and the inside of a grain heap is reduced, moisture condensation cannotoccur to the grain heap, the condition of grain mildewing is avoided accordingly, ageing is not easy to occur to the grain and the good moisture can be kept, and the stored grain quality is improved.

The invention discloses a treatment process and system for coupling, drying and pyrolyzing household garbage. The treatment process includes the steps that (1) the household garbage is subjected to crushing and magnetic separation pretreatment; (2) the household garbage is subjected to biothermal air coupling and drying treatment; (3) the household garbage is subjected to pyrolysis gasification through a pyrolysis gasification furnace; (4) pyrolysis produces combustible gas into a secondary combustion chamber for secondary combustion; (5) secondary combustion produces high temperature flue gasto pass through a quenching heat exchanger; (6) after the heat exchange, the flue gas is exchanged with the air through an air preheater; and (7) the flue gas is finally discharged through an exhaustgas treatment system. The treatment system includes a crushing magnetic separation device, a biothermal air coupling and drying treatment device, the pyrolysis gasification furnace, the secondary combustion chamber, the quenching heat exchanger, the air preheater, the exhaust gas treatment system, and a chimney. The system has the advantages of high pyrolysis treatment efficiency of the householdgarbage, high stability of garbage pyrolysis and gasification, high controllability of the process, and low difficulty in treatment of exhaust gas, and can be widely applied to the technical field ofhousehold garbage pyrolysis treatment.

The invention discloses a preparation method of boride reinforced silicon carbide ceramics, taking silicon carbide powder, yttrium aluminum garnet and boride micro-powder as main raw materials and comprising the following steps: 1. adding the main raw materials, binding agent and dispersant into de-ionized water followed by ball-milling and mixing to prepare water-base silicon carbide slurry; 2. spray drying the water-base silicon carbide slurry with a spray granulating technique to obtain the silicon carbide granulation powder; 3. molding the silicon carbide granulation powder by dry pre-pressing and cold isostatic final pressing to obtain high density silicon carbide green brick; and 4. placing the high density silicon carbide green brick in a vacuum pressure-free sintering furnace to be heated to 1,900-2,000 DEG C and kept for 1-1.5 hours to obtain boride reinforced silicon carbide ceramics. The boride reinforced silicon carbide ceramics prepared by the method has the characteristics of high hardness, high bending resistance, and excellent fracture toughness property, etc.

The invention discloses a method for preparing a shrimp soft can, which comprises the following steps: soaking frozen shrimps into a citric acid the mass concentration of which is 0.05 to 0.1 percent so as to unfreeze the shrimps, then removing the heads of the shrimps and taking glands out; boiling the shrimps subjected to head and gland removing in boiling water for 1 to 10min at a temperature of 80 to 100 DEG C so as to removing part of water of the shrimps; removing the shells of the shrimps subjected to boiling, then soaking the obtained shrimps in pickling liquid for 10min to 8h at a temperature of 25 to 60 DEG C, wherein the pickling liquid comprises the following compositions in percentage by mass: 20 to 50 percent of granulated sugars, 5 to 20 percent of refined salts and 1 to 10percent of monosodium glutamates; and drying the shrimps subjected to pickling 5 to 30min at a temperature of 70 to 120 DEG C. The preparation method is simple and feasible, the prepared shrimp soft can is a subarid peeled-shrimp soft can, and the shrimp meat is moderate in tightness of organizational structure, and has certain chew resistance; and the method can effectively restrain the browningphenomena of the shrimp meat in the processes of hot-working, drying, dehydration or sterilization, thereby maintaining the original inviting orange red of the shrimp meat.

The invention relates to low-salt lotus leaf minced meat slices. A preparation method comprises the following steps: adding 0.2-0.4 mass percent of dried lotus leaf powder with the granularity of more than 100 meshes; adding 10-20 mass percent of food grade calcium lactate to partially replace sodium salt in the meat slices, uniformly mixing with raw material meat and other auxiliary materials by virtue of a chopping process to form a uniform emulsion system, salting under low temperature conditions, and manufacturing according to a traditional processing technology of minced meat slices. According to the method disclosed by the invention, the content of sodium salt in the minced meat slices can be effectively reduced, fat oxidative rancidity of the minced meat slices in the processing and storage process is delayed, the fading speed of the minced meat slices is reduced, the flavor of the minced meat slices is improved, the elasticity and chewiness of the minced meat slices are improved, and the manufactured low-salt lotus leaf minced meat slices are good in taste, and unique, strong and long-lasting in flavor.

The invention discloses a preparation method of silicon carbide short fiber toughened and strengthened silicon carbide ceramics, which takes silicon carbide powder, yttrium aluminum garnet and silicon carbide short fiber as the main materials and sequentially comprises the following steps of: 1) adding the main materials, a caking agent and a dispersant into de-ionized water and preparing water-based silicon carbide slurry after ball-mill mixing; 2) adopting a sponging drying technique to carry out spray drying to the water-based silicon carbide slurry; 3) adopting 160-200MPa to carry out dry pressing and shaping to the obtained strengthened silicon carbide palletizing powder to obtain a silicon carbide biscuit; and 4) arranging the silicon carbide biscuit in a vacuum pressureless sintering furnace for sintering to obtain the silicon carbide short fiber toughened and strengthened silicon carbide ceramics. The invention simultaneously provides the silicon carbide short fiber toughened and strengthened silicon carbide ceramics prepared by the method. The silicon carbide ceramics is characterized by larger fracture toughness, high mechanical strength, and the like.

The invention relates to automatic food waste smashing and squeezing integrated equipment. The automatic food waste smashing and squeezing integrated equipment comprises a smashing mechanism, a spiral conveying mechanism and a pressing plug mechanism, wherein the spiral conveying mechanism comprises a spiral conveying roller, a filter barrel for filtering oil-water in smashed food waste coaxially sheathes the spiral conveying roller, a feeding hole is formed at one end of the filter barrel, and the other end of the filter barrel is provided with a residue discharge hole; a discharge hole of the smashing mechanism is communicated with the feeding hole; the pressing plug mechanism comprises an adjusting screw rod, a pressing nut sheathing the adjusting screw rod and a pressing plug disposed at the residue discharge hole, a pressing spring is arranged between the pressing plug and the pressing nut, and after the pressing nut is screwed, the pressing spring pushes against the pressing plug and then the pressing plug elastically presses residues at the residue discharge hole. The automatic food waste smashing and squeezing integrated equipment can well control the oil-water content in food waste, and is simple in structure and convenient to operate.

The present invention relates to a paint-free decorative furniture plate and particularly relates to a formaldehyde decomposition (purification) function plate and a preparation method thereof. The plate comprises a substrate layer and an upper surface layer decorative film paper layer and a lower surface layer decorative film paper layer which are respectively pressed and glued to the upper surface and the lower surface of the substrate layer. The gram weight of the upper surface layer decorative film paper layer or the lower surface layer decorative film paper layer is 60 to 150 grams per square meter. The upper surface layer decorative film paper layer and / or the lower surface layer decorative film paper layer is decorative paper which is impregnated with an amino resin solution and a formaldehyde decomposition solution, the thickness of the decorative paper is 0.08 to 0.12 mm, the thickness of the substrate layer is 2.5 to 25mm, and the substrate layer is an oriented strand board layer. The preparation method comprises the steps of (a) substrate sanding, (b) formaldehyde decomposition solution modulation, (c) decorative film paper manufacture, (d) assembly and (e) pressing. The formaldehyde purification plate has the advantages of lifelike decoration effect, low cost and good formaldehyde purification effect.

The invention discloses a lithium ion battery amide-type additive having film-forming and stabilizing functions and electrolyte containing the same. The invention relates to an amide-type additive, which is suitable for lithium ion battery and has the film-forming and stabilizing functions. The additive can prominently promote the forming of SEI membrane and at the same time can control water content of electrolyte, and thus the cycle performance and safety of lithium ion battery are improved. The structure of the amide-type additive is shown in the description, wherein the R represents a five-membered or six-membered nitrogen-containing heterocyclic group, such as pyrrole, imidazole, pyridine, pyridazine, pyrimidine, pyrazine, and the like.

The invention relates to a paint-veneer-free furniture plate, especially relates to a formaldehyde decomposing (purifying) functional biological plate, and a manufacturing method of the biological plate, and belongs to wood processing industry. The biological plate comprises a substrate layer, an upper surface decorative film adhesive paper layer pressed and adhered to an upper surface of the substrate layer, and a lower surface decorative film adhesive paper layer pressed and adhered to a lower surface of the substrate layer. The upper surface decorative film adhesive paper layer or the lower surface decorative film adhesive paper layer has the weight of 60-150 g / m2; the upper surface decorative film adhesive paper layer and / or the lower surface decorative film adhesive paper layer is decorative paper impregnated with an amino resin glue solution and a formaldehyde decomposing glue solution; the decorative paper impregnated with an amino resin glue solution and a formaldehyde decomposing glue solution has the thickness of 0.08-0.12 mm; and the substrate layer has the thickness of 2.5-25 mm. The manufacturing method comprises the following steps: a, substrate sanding; b, adjustment of the formaldehyde decomposing glue solution; c, manufacturing of decorative film adhesive paper; d, assembly; and press adhesion. The formaldehyde purifying biological plate is authentic in decorative effect, low in cost, and good in formaldehyde purifying effect.

This invention discloses a method for preparing nanometer complex silicon carbide ceramics. The production procedures are: (1), the main raw materials (silicon carbide, yttrium aluminium garnet), adhesion agent, water-soluble high molecular mixture sol, dispersing agent are added into de-ionized water, mixed by ball-milling, to produce water-based silicon carbide slurry with its solid content of 30-60%; (2), proceeding spray-drying to obtain powder; (3), two-step formation to obtain blank of silicon carbide; (4), being sintered in vacuum sintering furnace to obtain the final product. This inventive method is of simple process and the inventive product is with excellent properties.

The invention belongs to the field of feed processing devices and particularly relates to a smashing device and a smashing and squeezing integrated device with the smashing device. The smashing device comprises a machine frame and two rollers which are arranged below a feeding port and rotate oppositely. Each roller is provided with wheel tooth type movable cutters arranged spirally. The movable cutters on the two rollers are mutually staggered in the axial direction of the rollers. Upper fixed cutters are installed on the machine frame at intervals and located on the two sides of the portion below the feeding opening. The upper fixed cutters are meshed with the movable cutters. According to the smashing device and the smashing and squeezing integrated device with the smashing device, the double rollers are adopted and conduct smashing and cutting oppositely, the upper fixed cutters are also arranged, so that the problem that when straws of bananas and other crops are smashed and cut, the straws slide and are not prone to being cut off is solved, and the cutting and smashing efficiency is improved. The whole smashing and squeezing integrated device with the smashing device is simple in structure and easy to maintain, and intelligent control can be achieved for different working conditions at the same time; the whole smashing and squeezing integrated device with the smashing device can be disassembled, disassembled devices can be independently used, the feed processing efficiency and machining quality can be greatly improved, and the smashing device and the smashing and squeezing integrated device with the smashing device are particularly suitable for machining of banana straws.

The invention relates to a modified strengthened and toughened polyethylene solid-wall pipe, belonging to the technical field of a water supply and drainage device. The modified strengthened and toughened polyethylene solid-wall pipe comprises raw materials of the following weight portions: 100 portions of recycled high-density polyethylene, 18-30 portions of linear low-density polyethylene, 8-15 portions of polyethylene unbleached material and 3-6 portions of catalyst. The invention has the advantages that: the pipe is economical, and the application of the water / sewage drainage pipe can be expanded; non-renewable resources can be saved greatly by adopting the recycled high-density polyethylene; since the high-density polyethylene is modified, the tensile strength of the pipe can reach 24.5-27MPa, the elongation at break is up to 550-750 percent, and the pipe has good flexibility; the use of the catalyst in the formula is reasonable, and the formation of the pipe can be improved; the modification of the recycled high-density polyethylene by the linear low-density polyethylene can be ensured by the preparation method, and the strengthening and toughening effects can be achieved; and the pipe quality can be ensured.