63results about How to "Low water temperature" patented technology

The present invention relates to formulation components, such as organic catalyst compounds designed with time-controlled bleaching to increase color safety, compositions and laundry methods employing such organic catalyst compounds. More particularly, this invention relates to organic catalysts compounds such as quaternary imine bleach boosting compounds, quaternary oxaziridinium bleaching species, modified amines and amine oxides, imines, and / or oxaziridines, compositions and laundry methods employing such organic catalyst compounds.

A microwave hydro-thermal synthesis method of a zinc oxide nanostructure modified timber relates to a timber modification method by a nano-material. The invention solves the problems of long hydro-thermal time and high hydro-thermal temperature in a hydro-thermal synthesis method for preparing a nanoparticle protective layer on the timber surface in the prior art. The method provided by the invention is as below: 1, preparing a ZnO seed colloidal solution; 2, preparing a timber with ZnO seeds growing on the surface; and 3, placing the timber prepared in the step 2 into an aqueous solution mixed from zinc salt and an ammonia source for a microwave hydro-thermal reaction, so as to complete preparation of the zinc oxide nanostructure modified timber through microwave hydro-thermal synthesis. The invention employs the microwave hydro-thermal synthesis method to prepare nanometer zinc oxide on the timber surface. In the preparation process, the microwave radiation power is 1000-1500 W, and the hydro-thermal time is 10-90 min, and the hydro-thermal temperature is 40-120 DEG C. The method makes the synthesis technology of the nanoparticle protective layer on the timber surface simple and practicable. The invention can be applied to the field of functional improvement on timber.

The invention discloses on-line quenching and plate shape controlling technology for a 12 MnNiVR steel plate, comprising: a blank material cold installation step, a de-scaling step, a rough rolling step, a finish rolling step, a pre-straightening step and an on-line quenching step; wherein in the on-line quenching step, the steel plate enters a ultrafast cooling system with 18 groups of cooling headers, the ultrafast cooling system sets a water flow amount based on the steel plate target thickness, sets an area roller-way speed being 0.7-1.2m / s, sets a roller-way acceleration being 0.003-0.01m / s2, controls a cooling start temperature being 790-740 DEG C, and controlling a cooling final temperature being 180-270 DEG C, and the steel plate departs from the ultrafast cooling system when a cooling final temperature is 180-270 DEG C. The technology provided by the invention raises cooling uniformity, cooling efficiency and once plate shape qualified rate of an on-line quenched steel plate, simplifies a thermal refining technology flow of 12MnNiVR, and finally raises economic benefit of enterprises.

The invention belongs to the technical fields of comprehensive utilization of industrial solid wastes and energy materials, and especially relates to a method for preparing cell-grade lithium iron phosphate from pyrite slag. The pyrite slag is orderly subjected to the following steps: reduction calcination, acid soaking in sulfuric acid, impurity removing, and hydrothermal synthesis so as to obtain the lithium iron phosphate. The method converts pyrite slag into a lithium cell positive pole material lithium iron phosphate with a high additional value, and economically achieves comprehensive utilization of staple industrial solid wastes. The method has the advantages of simpleness, practicability, safety, reliability, low production cost, high yield, and little environmental pollution.

The invention discloses a selective inlet water temperature stabilizing device. The selective inlet water temperature stabilizing device comprises a water reservoir, a clapper door inflow device and a water taking building, wherein the clapper door inflow device and the water taking building are respectively arranged on the two sides of the water reservoir; and the bottom of the water taking building is connected with a water taking culvert pipe. The invention also discloses a water temperature value simulating and forecasting method. According to the invention, external seawater used as a power plant safety plant water source flows in through the device while higher water level and lower temperature of the external seawater are obtained; and the external seawater is conveyed into a safety plant cooling water taking pump house after cold water and hot water are sufficiently mixed and the surface is cooled; therefore, the temperature of the water taken from the safety plant water is obviously reduced while being compared with the variation gradient and the peak value of the water temperature at the external seawater taking opening so that the high peak value of the water taking temperature can be stabilized, the reduction amplitude of the safety plant water temperature can be also forecasted after using the system and the device, and design parameters are provided for building the selective water temperature stabilizing device.

The invention relates to an offshore natural gas liquefying method and an offshore natural gas liquefying device. The method comprises the following steps of: 1) pretreating natural gas extracted from seabed, and inputting into a heat exchange cold box; 2) continuously reducing pressure and temperature of preset carbon dioxide gas in a carbon dioxide pre-cooling circulating system, and introducing the carbon dioxide gas into the heat exchange cold box; 3) compressing preset nitrogen in a double nitrogen expansion refrigeration circulating system into high pressure nitrogen, introducing the high pressure nitrogen into the heat exchange cold box, precooling by carbon dioxide, directly reducing pressure and temperature of one path of nitrogen by using an expander, continuously precooling the other path of nitrogen and reducing pressure and temperature by using the expander, returning the two path of low pressure nitrogen to the heat exchange cold box, exchanging heat, raising the temperature, lifting the pressure, reducing the temperature, and returning to the heat exchange cold box; and 4) precooling the pretreated natural gas by using the carbon dioxide gas in the heat exchange cold box, introducing into a heavy hydrocarbon separation unit, gradually cooling the natural gas by the returned nitrogen, removing the heavy hydrocarbon by using a gas-liquid separator and a rectifying column, cooling, throttling and reducing temperature by using a throttle valve, introducing a gas-liquid mixture into a buffer tank, introducing a liquid phase into a storage tank for storage, discharging a gas phase from the top of the buffer tank and collecting the gas phase.

The invention discloses an independent water cooling device of a large-scale megawatt-level wind generating set. The independent water cooling device comprises at least a set of cooling system, wherein the cooling system comprises a device heat exchange water tank, the device heat exchange water tank is provided with a water inlet and a water outlet, the water inlet and the water outlet are connected with cooling water circulating pipelines, one cooling water circulating pipeline closing to one side of the water outlet of the device heat exchange water tank is provided with a plurality of temperature controlled switches, the other cooling water circulating pipeline at rear ranges of the temperature controlled switches is connected with a plurality of air-cooling water heat exchangers in parallel, each temperature controlled switch is connected with a contactor of one air-cooling water heating exchanger in a controlling way, and the cooling water circulating pipeline at the rear range of the water outlet of the air-cooling water heat exchanger is also provided with a temperature sensor, a pressure sensor and a water pump. The independent water cooling device has a good cooling effect, can automatically operate according to water temperature and can be installed in an engine cabin of a draught fan, the installation is convenient and simple, the weight of an engine base of the draught fan can be greatly reduced, the maintenance can be convenient, the master control load of the draught fan can be effectively reduced, and the manufacturing cost of the draught fan can be reduced.

The invention discloses a preparation method of a ceramic nanofiltration membrane. A modified sol-gel method is combined with a hydrothermal method to prepare a complete and defect-free ceramic nanofiltration membrane, glycerin is added to the modified sol to inhibit crystal transformation and prevent grain growth, a high-purity, uniform-grained nanoparticle solution is prepared through hydrothermal reaction, meanwhile, mineralizer and a surface active agent are added to the hydrothermal reaction to reduce the hydrothermal temperature and inhibit the polymerization of crystals, nano-particleswith a particle size of 3-5 nm are prepared, then a plasticizer and a binder are added, and the ceramic nanofiltration membrane is prepared.

The invention discloses a method for producing porous ceramic materials by adopting the low-temperature hydrothermal method. The method utilizes the hydrothermal reaction to immerse a ceramic formed body in silicon dioxide sol; according to the dissolution-precipitation mechanism, part of silicon dioxide particles can be precipitated on the surfaces of ceramic grains to play a bonding role, thereby producing the porous ceramic materials. The hydrothermal temperature in the preparation method is lower and can not cause the oxidation of non-oxide ceramics during the sintering process.

The invention relates to the technical field of refrigerant-free air conditioning units, in particular to a refrigerant-free air conditioning unit. A surface air cooler and a device for performing equal-enthalpy heat-insulation dehumidification treatment of the air cooled by the surface air cooler are arranged indoors. A cooling fan is arranged on an outdoor side wall, a first wet curtain component is arranged close to an air inlet which is formed on a side wall corresponding to the outdoor side wall on which the cooling fan is arranged, the first wet curtain is also connected with the surface air cooler arranged indoor through a first water supply component, and an evaporation cooling system consisting of the cooling fan, the first wet curtain component, the first water supply component (3) and the surface air cooler provides circulating cooling water for the surface air cooler. Outdoor fresh air is supplied by an indoor fan to the surface air cooler to be cooled and to the second wet curtain component to undergo equal-enthalpy heat-insulation dehumidification, and then enters rooms from an indoor air outlet. After the outdoor air is treated by the surface air cooler and the indoor wet curtain component, the temperature difference between indoor inlet air and outlet air reaches 8 to 15 DEG C, and thus, the cooling effect of a unit with a refrigerant system is achieved.

A preparing method of a graphene-Au-TiO2 multi-component composite nanotube material is provided. The method includes a step of preparing a raw material mixture, namely a step of weighing available nanometer particles TiO2 and NaOH raw materials according to a mass ratio of 1:8, adding the TiO2 and the NaOH into a corundum crucible, separately weighing graphene powder and a gold compound into the corundum crucible, fully mixing the materials and keeping the mixture for later use; a step of high-temperature melting, namely a step of putting the corundum crucible containing the material mixture at room temperature into a vacuum high-temperature furnace isolated from air, closing the door of the furnace, opening an argon flow valve, feeding argon to remove air in the furnace body, raising the temperature from room temperature to 400-500 DEG C at a temperature raising speed of 5 DEG C / min, melting the raw material mixture, cooling the high-temperature furnace to room temperature, taking the corundum crucible out and stopping argon, with the raw materials forming titanate mixed alkali-melt frit; a step of performing extraction with boiling water; a step of performing hydro-thermal treatment under atmospheric pressure; a precipitating and washing step; and a step of performing calcination to obtain a finished product. The method has characteristics of a low cost, short time, a greatly increased length and stable properties of the prepared nanotubes, and capability of effectively improving photocatalytic properties of the composite nanometer material.

The invention discloses an auxiliary vapor compression refrigeration system for semiconductor refrigeration driven by solar photovoltaic power generation. The auxiliary vapor compression refrigeration system comprises a common vapor compression refrigeration system body and a photovoltaic power generation driving semiconductor refrigeration system body which are coupled through a liquid accumulator; the photovoltaic power generation driving semiconductor refrigeration system body comprises a photovoltaic conversion device, the photovoltaic conversion device converts solar energy into electric energy, and the electric energy is output to serve as a direct current power source of a semiconductor refrigeration element; one end of the semiconductor refrigeration element is a cold end, the other end of the semiconductor refrigeration element is a hot end, and the cold end conducts heat exchange with intermediate medium water in the liquid accumulator; and the water in the liquid accumulator and refrigerants at an outlet of a condenser in the common vapor compression refrigeration system body are subjected to head exchange in a tube-shell type heat exchanger, the water passes through the shell pass, and the refrigerants pass through the tube pass, so that the refrigerants reach a supercooled state. According to the auxiliary vapor compression refrigeration system, the refrigerating capacity of the system is increased so that the purposes of improving the system energy efficiency ratio and reducing system energy consumption can be achieved.

Heat exchanger packs having a first set of passageways for receiving a stream of ambient air and a second set of passageways for receiving a stream of warm water laden air is disclosed. The first set of passageways and second set of passageways being separate and permitting the warm water laden air stream to be cooled by the stream of ambient air so that water can condense out of the warm water laden air stream. Cooling tower configurations including the heat exchanger pack are disclosed for achieving effluent plume abatement, and capture of a portion of the effluent for replacement back into the cooling tower reservoir or as a source of purified water.

The intelligent quick heating drinking water machine includes a casing, a bottle seat, a water bucket, a power source switch, a hot water outlet, a quick heater and water heating control circuit. The quick heater has a water inlet connected to the water bucket a water outlet connected through a hot water solenoid to the hot water outlet, an electrically heating tube heater connected via power source switch to outer power source and with electrically heating film coated in the outer surface of the electrically heating tube and inside cavity as the water passage, and a water heating control circuit with high temperature on contact and low temperature off contact and connected to a heat sensor and the hot water solenoid in the electrically heating tube heater. The present invention can avoid repeated heating, and has use convenience, high safety, low power consumption, no scaling and effective control on water outflowing.

The invention discloses an electric power plant water diversion open ditch flow guide heat insulation device and a design method thereof. The device comprises a folded plate type flow guide plate and a flat plate type flow guide plate, wherein the folded plate type flow guide plate comprises a first inclined plate and a first flat plate; one end of the first inclined plate is arranged at an entrance position of an open ditch; the other end of the first inclined plate is connected with the first flat plate; the side edge of the first inclined plate and the side edge of the first flat plate are fixed on the side wall of the water diversion open ditch; the flat plate type flow guide plate is arranged in a connecting position of an exit of the open ditch and a water inlet rectifier box, and comprises a second flat plate; the side edge of the second flat plate is fixed on the side wall of the water diversion open ditch. According to the design method provided by the invention, the design parameters of the current water diversion open ditch and rectifier box culvert and the like is obtained; hydromechanics software is used for building the open ditch flow state of the device provided by the invention; the value calculation optimization is further performed to achieve the goal. The electric power plant water diversion open ditch flow guide heat insulation device and the design method have the advantages that the temperature rise influence of sun radiation on the water body in the water diversion open ditch conveying process can be effectively reduced; the cooling water taking temperature of an electric power plant is reduced; the efficiency of a power generating set is improved; high economic benefits and application popularization values are realized.

The invention discloses a seabed cage-breeding device for comb shells and solves the problems that in the prior art, the breeding type is easily affected by environment, so that the death rate of the comb shells is high and the profit is low. The technical scheme of the invention is that: the seabed cage-breeding device comprises a netting, a support frame and a mouth-closing tube, wherein the support frame is arranged in the netting and connected with the netting to support the netting, and the mouth-closing tube is used for closing the mouth of the netting. The invention designs the novel seabed cage-breeding device; by adopting the seabed cage-breeding method, not only the problem that the raft breeding is affected by the surface temperature fluctuation and high water temperature in summer is solved, but also the problem of low recapture rate existing in the bottom sowing enhancement breeding method is also solved, the survival rate of scallops is high and the breeding density of young comb shells can be self-controlled according to actual conditions.

The invention relates to a method for synthesizing a tungsten trioxide electrochromic material by one step with assistance of citric acid. The method comprises the following steps: dissolving a tungsten source and a chelating agent in a molar ratio of (0.4-1.2):1 in water, stirring the mixture uniformly, and adding a morphology control agent to obtain a mixed solution, wherein the molar ratio of the morphology control agent to the tungsten source is (0-0.1):1; adjusting the pH value of the mixed solution to be 0.5-2 by acid to obtain a tungsten trioxide precursor solution; placing a conductiveglass substrate in the tungsten trioxide precursor solution, and growing a tungsten trioxide electrochromic nano-material on the surface of the conductive glass substrate at 85-95 DEG C. The method is easy to operate, and has the characteristics of low cost, low temperature requirement and the like.

The invention discloses a method for treating irrigation sediment by using a surfactant pretreatment-hydrothermal oxidation-thermal cracking coupling method. The method comprises the following steps of firstly, adding a surfactant to preliminarily destroy an oil-water mixed system and an oil-mud colloid system; performing pretreatment filtration dehydration, deeply destroying an emulsifying structure and a micellar structure by utilizing the characteristic of high ionization degree of water in a hydrothermal oxidation process and utilizing the oxidation characteristic of an oxidant, carrying out thermal catalytic oxidation on pretreated and dehydrated tank bottom muddy water, filtering, further dehydrating to obtain crude oil containing a very small amount of water and mud, filtering the crude oil containing a very small amount of water and mud, and separating the crude oil and oil-containing mud sand, recovering the crude oil; and carrying out thermal cracking on the separated mud sand containing a small amount of crude oil to recycle part of light oil so as to obtain mud sand with the organic matter content of less than 1%. The method is simple and convenient in operation process, the equipment requirement is low, the method is green and environment-friendly, the technical difficulties of low energy consumption and high cost in the prior art can be solved, and technical advantages and engineering application value are large.

The invention relates to a graphene-Re-TiO2 multi-component nanotube material preparation method. The method comprises the following steps: preparation of mixing raw materials: weighing nano particles TiO2 sale in the market and a NaOH raw material according to the mass ratio of 1:8, dumping the materials into a corundum crucible; respectively weighing a compound of graphene powder and rare earth and placing the compound in the corundum crucible, fully and uniformly mixing the materials for standby; performing high temperature fusion: under room temperature, placing the corundum crucible equipped with the mixing raw materials into a vacuum high temperature furnace which can isolate the air, closing a furnace door; opening an argon flow valve, introducing argon to remove the air in the furnace body; heating the materials to the temperature of 400-500 DEG C with the heating speed of 5 DEG C / min, melting the mixing raw materials; cooling the high temperature furnace to room temperature, taking the corundum crucible out, turning off argon, forming titanate mixing alkali fusion clinker by the raw materials; extracting the material by boiling water, performing hydro-thermal processing under normal pressure; performing precipitation washing, and calcining the material to obtain the finished product. The method has the advantages of low cost and short required time, the length of the prepared nanotube is greatly increased, the property is stable, and the photocatalysis characteristic of the composite nano-material can be effectively increased.

The invention relates to an apparatus for cooling and maintaining the water temperature in the live wells of fishing vessels. This twelve volt singular device is applied through the live well wall, and through use of thermoelectric technology the ambient water temperature within the live well is decreased. The importance of cooler water is that holds more oxygen and lowers metabolism in fish, which in turn increases the survival rate of captive fish. This invention is targeted for use by sports fisherman for use in tournaments to avoid penalties for dead fish and to promote the conservation of fish for ecological purposes.

An apparatus and method for producing and storing ice on the sea using sub-zero cold air of the winter season, to achieve an earlier freezing period, and increasing the area and thickness of the ice layer, to suppress the melting of ice sheets and glaciers and suppress and overcome global warming as well as its side effects. The apparatus and method involve compressing cold air; injecting the compressed cold air into a storage tank; supercooling water using the injected cold air; forming an ice layer by misting the supercooled water into the sea; and increasing a thickness of the ice layer by additionally misting water onto the ice layer formed at water level.

The invention discloses a stirrer of a cooling tower. The stirrer of the cooling tower comprises a heat exchange tube. A plurality of branch tubes are spirally arranged on the outer wall of the heat exchange tube. Blades are arranged at the ends of the branch tubes. A water inlet pipe and a water outlet pipe are arranged on openings of the two ends of the heat exchange tube in a sealed mode through bearings correspondingly. A cooling box is arranged at the bottom of the tower body and is connected with the water inlet pipe and the water outlet pipe. A water pump is arranged on the water inletpipe. The right end of the heat exchange tube extends out of a power body. A driving gear is arranged on the outer wall of the right end of the heat exchange tube and is connected with a servo motor through a transmission gear set matched with the driving gear. By adoption of the stirrer of the cooling tower, a large quantity of materials can be stirred and dispersed, and meanwhile, the overall cooling efficiency is improved.

The invention discloses a method for preparing a lithium ion sieve adsorbent MnO2.0.5H2O and a precursor thereof Li1.6Mn1.6O4. The method comprises the following steps: carrying out one-step hydrothermal synthesis on raw materials inorganic manganese salt and lithium salt to obtain an intermediate, and roasting at low temperature to obtain the required precursor Li1.6Mn1.6O4; and carrying out acid treatment on the precursor to extract Li so as to obtain an H-type ion sieve, washing with water, filtering, and drying to obtain the ion sieve adsorbent MnO2.0.5H2O which has a screening effect on lithium ions. The invention has the advantages of simple process route and mild preparation conditions; and the obtained ion sieve has the advantages of low solution loss, high adsorption rate and high adsorption capacity.

The invention discloses a method for extracting high-grade powdered iron from low-grade sulfuric-acid residue. The method comprises the following steps of leaching pretreatment, hydrothermal treatment, washing and dilute acid soaking. According to leaching pretreatment, the sulfuric-acid residue and leaching medicaments are evenly mixed, react for 30 minutes to 120 minutes and then are filtered to obtain pretreatment filter residue and pretreatment filter liquor; according to hydrothermal treatment, the pretreatment filter residue and extractants are evenly mixed, and carry out hydrothermal reaction at the temperature of 120 DEG C to 250 DEG C for at least two hours to obtain hydrothermal materials; according to washing, the hydrothermal materials are dissolved with the sufficient amount of water and then are filtered, and washing filter residue and washing filter liquor are obtained; according to dilute acid soaking, dilute acid is used for soaking and washing the filter residue, the filter residue is soaked for three to 30 minutes and then is filtered, and the high-grade powdered iron and dilute acid filter liquor are obtained. The method is easy to operate and wide in application range, resources are circularly utilized, the production cost is reduced, the pollution to the environment is small, the obtained powdered iron product is stable in quality, the grade of the iron reaches 68 percent, the content of sulphur in the powdered iron is lower than 0.1 percent, and the yield of the powered iron is more than 85 percent.

The invention provides a solar water heating system. The solar water heating system comprises a solar heat collector, a circulating water tank and a heat preservation water tank, wherein a first water inlet of the circulating water tank is connected with a water inlet pipe; a first switching valve is arranged on the water inlet pipe; a first water outlet of the circulating water tank is connected with a circulating pump; a water outlet of the circulating pump is connected with a second water inlet of the circulating water tank through the solar heat collector (1); a second water outlet of the circulating water tank is communicated with the heat preservation water tank through a second switching valve; a water outlet of the heat preservation water tank is connected with a user side through a booster pump; exhaust overflow pipes are arranged at the top of the circulating water tank and the top of the heat preservation water tank; a blowoff valve is arranged at the bottom of the circulating water tank. The solar water heating system fully heats water, is large in heating amount and high in solar energy utilization rate, and can meet water demands of multiple users.

Method and plant for generation of synthesis gas, comprising the steps of air fractionation to give oxygen, nitrogen and tail gas, gasification of a hydrocarbonaceous fuel to give crude synthesis gas and cleaning of the crude synthesis gas by removal of acid gas by means of cryogenic absorption, wherein the absorbent is cooled by means of a compression coolant circuit and the cooling water used is cooled by evaporative cooling by means of the tail gas obtained in the air fractionation.

The invention discloses a novel cooling tower. The novel cooling tower comprises a tower body internally forming a cavity, an opening is formed in the top part of the tower body, and an opening type annular wall is formed on the periphery of the top of the tower body; and the novel cooling tower is characterized in that a first cooling mechanism is arranged above the opening, and a second coolingmechanism is arranged inside the cavity. According to the novel cooling tower, a large amount of materials can be processed at the same time, the processing time is shortened, the overall working efficiency is improved, meanwhile, heat taken away through the evaporation of a wet curtain is used for carrying out primary cooling on the materials, secondary cooling is carried out on the materials through a heat exchanger, so that the overall cooling efficiency is greatly improved.

A device for UV and low temperature treatment for increasing a functional material content in a plant including a work table having an upper plate elevated from a floor, a cultivation bed disposed on the upper plate and including an accommodation hole to accommodate soil or culturing solution therein, and a flow tube disposed in the soil or culturing solution to supply or drain water to and from the accommodation hole, a supply portion to circulate water in the flow tube to lower the temperature of water, a light emitting portion including a pillar adjustable in height and a UV light source emit UV light toward an upper portion of the cultivation bed, and a power generator including a servo motor disposed below the work table, and a bracket configured to adjust a location of the light emitting portion with respect to the side surface of the work table.

The invention relates to the technical field of nano materials, and in particular to a nano Co3O4 / TiO2 semiconductor composite film and an application thereof. The Co3O4 / TiO2 semiconductor composite film can be used as an anti-corrosion protective film for inhibiting metal corrosion. Co3O4 nano cube particles are loaded on a TiO2 array tube orifice through a low-temperature hydrothermal method, and calcining is carried out to form a stable Co3O4 / TiO2 composite film; and the narrow-band-gap p-type semiconductor Co3O4 nano-particles are loaded on an n-type TiO2 nanotube orifice to reduce electron-hole recombination so as to obtain the nano Co3O4 / TiO2 semiconductor composite film. The Co3O4 / TiO2 composite film photoanode is coupled with 304 stainless steel, so that the potential of the stainless steel can be reduced to minus 0.66V; and the composite film has a good cathode protection effect under the dark state, and has the advantages of being simple in preparation method, high in visible light utilization rate and capable of providing continuous protection under the dark state.

The invention provides a large-scale solar water heater which comprises heat collectors and a heat preservation water tank, wherein a water inlet pipe is arranged at the water inlet of each heat collector, a first stop valve and a first filter gate are arranged on the water inlet pipe, the water outlet of each heat collector is connected with the water inlet of a heat preservation water tank through a second stop valve and a second filter gate, the water outlet of the heat preservation water tank is connected with a user end through a third stop valve and a pump, and a temperature sensor is arranged on the heat preservation water tank. In the solar water heating system provided by the invention, a plurality of heat collectors are connected in parallel for heating, the heating effect is good, well heated hot water is placed into the heat preservation water tank for heat preservation, when being required for use by the user end, the heat water can be extracted; moreover, an electric heater is arranged in the heat preservation water tank so as to play an auxiliary effect and prevent the temperature of water inside the heat preservation water tank from being lowered after long time; the solar water heating system provided by the invention can sufficiently heat water, the heating quantity is high, the availability of solar energy is high, and requirements of users for water using can be met.