415results about How to "Save land area" patented technology

A suspension maglev rail transit system includes an orbital system, a suspension system, a control system and a car system, wherein the control system comprises a drive system, a guidance system and asuspension control system, wherein the track system is suspended in the air through upright posts, the car system is suspended vertically below the track system through the suspension system, and thedrive system and the guidance system cooperate to drive the car system to operate in the track system. The invention utilizes the levitation force with the permanent magnet repulsion force as the main force and the electromagnetic regulation as the auxiliary force to suspend the car on the air track, and realizes the stable operation through the non-contact traction of the linear motor. The invention has the advantages of low energy consumption, high safety, no land occupation, low cost, strong climbing ability, small turning radius and wide adaptability.

The invention provides a high-level drift water channel system, relating to an above-water slideway, in particular to a high-level drift water channel system used for sports or leisure. The high-level drift water channel system is provided with a water guide channel device, a cockboat, at least a water pump spraying device and an above-water platform device; the water guide channel device is provided with a water guide channel and a vertical column; the cockboat is provided with a wheel and a spraying push-force device; the cockboat is arranged in the water guide channel; the water pump spraying device is provided with a water accumulation channel, a water pump, a pipeline, a nozzle or a water outlet; the water accumulation channel is connected with a water channel; the water pump is connected with the water accumulation channel; the water pump is connected with the nozzle or the water outlet on the water guide channel by the pipeline; one water pump spraying device is provided with at least one nozzle or water outlet; the above-water platform is arranged on the water surface and is used for fixedly supporting the vertical column of the water guide channel; and the above-water platform device is provided with a floating body, a platform, a pile column and a lifting power mechanism.

The invention discloses a precession-type backfill grouting ground source thermal energy conversion precast pile device, which comprises a plurality of precession-type backfill grouting prefabricated screw piles respectively embedded into pile holes, wherein a vertical heat exchanger is embedded in each screw pile; the inlet end and the outlet end of each vertical heat exchanger respectively extend out of an opening at the upper end of the screw pile to be respectively connected with a horizontal liquid-feeding collecting pipe and a horizontal liquid outlet collecting pipe in a bearing platform or a cushion layer; centring brackets are arranged at an interval of 1-3 m along the length direction of each vertical heat exchanger; each precession-type backfill grouting prefabricated screw pile comprises a hollow pile core, wherein the bottom of the pile core is provided with a cone-shaped pile head; a screw blade is arranged on the position far away1-3m from the lower part of the outer wall of the pile core; and a post grouting reinforcing layer is poured between the middle upper part of the outer wall of the pile core and a pile hole wall. The precession-type backfill grouting ground source thermal energy conversion precast pile device comprises a plurality of precession-type backfill grouting prefabricated screw piles, and the vertical heat exchanger is embedded in each screw pile; the pile foundation construction and the ground source heat pump construction are integrated so as to avoid a drilling and pipe-laying program of a ground source heat pump system on the ground, greatly lower the front-end investment cost and save the land use area; and the post grouting reinforcing layer is poured between the middle upper part of the outer wall of the pile core and the pile hole wall so as to enlarge a heat conduction area, improve the heat conduction performance and simultaneously improve the pile body bearing capacity.

The invention provides a method for treating refractory wastewater by virtue of a supercritical water oxidation technology. The method comprises the following steps of: feeding the preheated wastewater into a salt separator for supercritical desalination, heating an oxidant which is preheated previously through a heat exchanger to a desired temperature, feeding the heated oxidant and the desalinated wastewater into a supercritical water oxidation reactor from the two ends of the reactor, respectively, controlling the system pressure by a back pressure valve, and carrying out a supercritical water oxidation reaction to degrade pollutants in the wastewater into non-toxic matters such as CO2, N2 and H2O; feeding the clean high-temperature and high-pressure fluid obtained after the reaction into the heat exchanger to exchange heat with the wastewater and the oxidant, respectively, and then cooling and separating, returning the excessive oxidant to the supercritical water oxidation reactor and causing the liquid into a normal-pressure gas-liquid separator, discharging the gases such as CO2 and N2 through the top of the normal-pressure gas-liquid separator, and discharging the treated clean water from the bottom of the normal-pressure gas-liquid separator. The method for treating the refractory wastewater by virtue of the supercritical water oxidation technology has the advantages of being high in wastewater treatment efficiency without secondary pollution, and suitable for treating the refractory wastewater different in concentration.

An ecological method using artifical marshland system for controlling N-P pollution includes such steps as sequentially flowing the rain or sewage in sand deposition pool, in stage-one free-surface artificial marshland (staying for more than 1.5 hr), in zeolite undercurrent marshland containing zeolite and cinder (staying for more than 1 hr), and in stage-two free-surface artificial marshland (staying for more than 8 hr). Its advantage is high effect.

The invention relates to the technical field of bicycle management, in particular to an intelligent environment-friendly bicycle parking device which comprises a tower body, a PLC control system arranged on the tower body, a rotating mechanism in the tower body, and a lifting mechanism in the tower body, wherein a bicycle packing opening and a bicycle taking opening are formed in the tower body; conveying belts and intelligent card readers are arranged in the bicycle packing opening and the bicycle taking opening respectively; a plurality of bicycle parking brackets are arranged on the inner side wall of the tower body; the lifting mechanism is arranged on the rotating mechanism; an electro-hydraulic movable manipulator and a scanning mechanism are arranged on the lifting mechanism; the rotating mechanism, the lifting mechanism, the conveying belts, the intelligent card readers, the electro-hydraulic movable manipulator and the scanning mechanism are electrically connected with the PLC control system. The intelligent environment-friendly bicycle parking device is safe, reliable, neat in parking, intelligent, environmentally friendly, fast and convenient in parking and taking, and small in occupied area, and has the advantages that the owner of a bicycle needs not to worry about stealing and knocking of the bicycle any more, and the urban land area is saved.

The invention relates to a large-diameter steel sleeve heat exchange device capable of extracting the geothermal energy, and belongs to the technical field of heating ventilation air conditioners capable of saving energy and reducing emission. The device mainly includes a ground source heat exchange well composed of a steel sleeve with the bottom being sealed, a PE inner tube, a filtering device, an impurity precipitation groove, a heat insulating plate and a water circulating flow diversion device. According to the connection relation, the steel sleeve is inserted into the ground, the ground source heat pump heat source side returned water is communicated with an upper end opening of the steel sleeve, and the PE inner tube is arranged in the steel sleeve; the filtering device is fixed inside the bottommost end of the PE inner tube; the impurity precipitation groove is formed in the bottommost end of the steel sleeve well; the heat insulating plate wraps the PE inner tube; the water circulating flow diversion device is arranged at a water inlet of the well and connected to the PE inner tube. By means of the large-diameter steel sleeve heat exchange device capable of extracting the geothermal energy, the problem that a soil source heat pump system is large in occupied space is solved, and the heat exchange amount of a single-opening ground source well is greatly increased.

The invention discloses a large-scale photon capture bioreactor for water purification and aquaculture. The bioreactor comprises a lockable three-dimensional building space. Each plane layer in the lockable three-dimensional building space is provided with a sinuous water channel. Each channel is provided with a water inlet and a water outlet. A plurality of filtering units are installed in each water channel at intervals. In each filtering unit, plants are planted on the water surface by a floating planting method, and aquatic animal and microorganisms are underwater. Plant growth irradiating lights with adjustable height are suspended above the plants by the floating planting method. An impeller is installed at the lower end of the water outlet of the water channel in the upper layer. The impellers are connected to an electric generator. The water inlet of the water channel in a lower layer is installed below the corresponding impeller. Water to be purified is fed to the water inlet of the water channel in the top layer of the three-dimensional building space firstly. The bioreactor mainly has advantages of easily controllable quality, high reaction efficiency, small occupied space, low investment, convenient management, low operation cost, no pollution in the ecological production process, and significant economic benefit.

The present invention relates to an underground pipe alkali removal technology, which is characterized that an alkali removal pipe with filtration holes are paved 0.5-5 meters underground with an interval of 10-1000 meters. Through paving the alkali removal pipe one time, the present invention can be used for a plurality of years, present invention underground water with alkali enters into the alkali removal pipe and gets removed through the leakage function, and the alkali removal effect is very good. Land above the alkali removal pipe can be used for plantation, which saves land occupied by an alkali removal channel, and the land utilization rate and economic benefits of land are increased, and the production cost is lowered.

Disclosed in the present invention is a production process for electro-statically coating a wood door, which comprises the following steps: loading material, removing dust, humidifying, spraying, leveling and preheating, solidifying, and unloading material. The process is characterized in that, in the step of removing dust, a conveying chain is used for conveying a workpiece into a sealed dust-removing chamber, a rotating brush is used for removing dust from the two sides of the workpiece, and an air drafting cover is used for absorbing and collecting the dust swept from the workpiece into a dust collecting box which is filled with water; in the step of spraying, an electro-static spraying mode is adopted for spraying a polyurethane ultraviolet light solidifying coating on the workpiece. The spraying mode can be used for promoting the use ratio of the coating, reducing the VOC emission, and obtaining a more uniformly coated layer.

The invention relates to a deep treatment method of garbage leachate, which is characterized in that (1) the garbage leachate, positioned in a denitrification pool, is made to have denitrification reaction by continuous push flow; (2) then the garbage leachate in the denitrification pool flowing into a nitrification pool is made to have nitrification reaction by continuous jet and blast aeration; DO is controlled from three to five mg / L; (3) the nitrified garbage leachate, flowing into a denitrification pool positioned behind, is made to have denitrification reaction by continuous push flow and the addition of carbon source; the concentration (mg / L) ratio of the carbon source and nitrate nitrogen ranges from two point zero to one, to four point five to one; (4) the wastewater after denitrification in the denitrification pool positioned behind is transported into a tubular ultrafilter; then the solid and the liquid of the wastewater are separated by the membrane component of the ultrafilter; clear liquid is transported to a nanofiltration device; concentrated liquid reflows into the denitrification pool; (5) the clear liquid after ultrafiltration is transported to a nanofiltration device; clear water is exported after the clear liquid is filtered by the membrane component of the nanofitration device. The deep treatment method of garbage leachate has the advantages of increasing the removal rate of ammonia nitrogen and total nitrogen.

The invention discloses a multifunctional three-dimensional type community shared expressage delivering system. The multifunctional three-dimensional type community shared expressage delivering systemcomprises a delivering port with an opening provided with a door handle, an intelligent delivering system, an intelligent carrying system, a goods receiving port and a carrying system. The intelligent delivering system comprises a code scanner, a resident database and a master controller. The code scanner obtains recipient information on expressage parcels, the master controller obtains residentinformation and generates a first drive signal, and a first door panel is opened. The intelligent carrying system comprises a camera and a face recognition module, and accordingly residents can be assisted to convey goods upstairs through face recognition. The carrying system comprises a transportation passage, a transportation plate, a track, a thruster, a chain and a motor. By means of the multifunctional three-dimensional type community shared expressage delivering system, expressages delivered in a unit port are directly conveyed to corresponding resident homes, and the workload of couriers is reduced. The residents can directly convey objects to the goods receiving port through the carrying system, accordingly, conveying of personal objects of the residents is convenient, the residents are prevented from carrying the objects upstairs, and convenience is provided for resident life. Arrangement of traditional expressage cabinets in the community is avoided.

The invention provides a slot type solar heat-collecting device and belongs to the technical field of solar energy utilization in the new energy source field. The slot type heat-collecting device is mainly used for solving the problems of connecting the pipelines, increasing the heat-collecting efficiency, increasing the volume, lowering the manufacturing cost, and the like. The device is characterized in that the end part of a vacuum heat-collecting pipe at a focus axis of a parabola slot type condenser lens is fixed on a bracket and the condenser lens is rotated around the heat-collecting pipe in order to track the sun, thereby being convenient to connect the pipelines and relieve the load of the condenser lens. The heat-collecting pipe is of a spiral runner through type structure, is provided with a cylindrical glass pipe shell on the exterior and is provided with a heat-collecting core pipe on the interior for axially passing through the vacuum glass pipe, so as to increase the heat-absorbing uniformity and heat-collecting effect and reduce the resistance. The heat-collecting core pipe is connected to an end part sealing element through a compensator, thereby being capable of freely dilating and maintaining the vacuum tightness. A plurality of vacuum heat-collecting pipes are serially connected; and when the vacuum seal materials cannot meet the temperature demand, an end part structure for reducing the work temperature of the sealing filler is adopted.

The invention relates to a light-duty unmanned type electric vehicle and a tridimensional electrified traffic lane, belonging to the technical field of traffic and transportation systems. The light-duty unmanned type electric vehicle is driven by electric power and on the special tridimensional electrified traffic lane, and the light-duty unmanned type electric vehicle realizes an unmanned function through preset running speed, running routes, the pull in braking and the pull out startup of the light-duty unmanned type electric vehicle, which are controlled by stations, and the like, can also safely and fast pull out of and pull into the tridimensional electrified traffic lane and turn left and right to change another tridimensional electrified traffic lane to drive. The invention aims to provide a novel energy-saving environment-friendly high-efficiency transport facility, solves the problems of traffic safety, tail gas pollution, petroleum resource scarcity, and the like generated in the using process of a common automobile and provides more contribution for socioeconomic development.

The invention discloses a multistage-series constructed wetland sewage treatment system and method based on solar energy, which are used for multistage biochemical treatment on sewage. The sewage treatment system comprises an A<2> / O treatment device and a constructed wetland treatment system, which are connected in series; the constructed wetland treatment system is formed in such a way that a vertical flow constructed wetland and a horizontal flow constructed wetland are connected in series, and arranged in a shed film photovoltaic solar greenhouse with a ventilation device; an amorphous silicon film solar panel is laid on the outer surface at the top of the shed film photovoltaic solar greenhouse; when sun light energy irradiates the amorphous silicon film solar panel, one part of sun light energy is converted into electric energy, while the other part of sun light energy penetrates the amorphous silicon film solar panel to be used for plant photosynthesis. The sewage treatment system is high in efficiency, and the shed film photovoltaic solar greenhouse meets the illumination and temperature requirements of plants in normal growth in all seasons, achieves the low-cost solar energy generation, and has favorable economic benefits and environmental benefits.

The invention provides an online acid adding method which adds acid liquid to a material liquid to be added with acid by adopting a Venturi tube to form an acidic material liquid. The Venturi tube includes an entrance segment, a contraction segment, a throat segment and a diffusion segment, wherein the entrance segment is connected with the pipe of the material liquid to be added with acid; the diffusion segment is connected with a static mixer; and an acid liquid inlet is arranged on the throat segment of the Venturi tube. The online acid adding method comprises the following steps: introducing the material liquid to be added with acid into the Venturi tube from the entrance segment, and flowing to contraction segment, the throat segment and the diffusion segment; and introducing the acid liquid from the throat segment of the Venturi tube into the Venturi tube, online mixing with the material liquid flowing to the diffusion segment to form the acidic material liquid, and flowing to the static mixer through the diffusion segment for further mixing. The online acid adding method can achieve good mixing effect through the dynamic quantitative mixing process of the acid liquid and the material liquid according to the ratio.

The invention provides a double-station automatic grinding and cutting machine for ceramic green body tubes. The machine includes a machine frame, a storage silo, a feeding mechanism, a delivery mechanism, a ceramic green body tube grinding station and a ceramic green body tube cutting station; the ceramic green body tube grinding station is on the left side of the cutting station; the left side of the feeding mechanism is provided with the storage silo, a feeding air cylinder is located at the tail end of the storage silo, and the tail end of a storage silo supporting beam is fixedly provided with a guide plate for ceramic green body tube dropping; the delivery mechanism includes a delivery bracket driving air cylinder and a double-V-shaped groove delivery bracket which are fixed together, and the side of the double-V-shaped groove delivery bracket is fixedly provided with a guide slider; the grinding station includes a core-free supporting wheel, a magnetic-driving device and an abrasive belt grinding device; the cutting station includes a core-free supporting wheel, a magnetic-driving device and a cutting device and further includes a workpiece discharging mechanism. The machine has the advantage that ceramic green body tube surface grinding and ceramic green body tube two-end excess material cutting can be achieved with one machine.

This invention discloses a semi-continuous centrifugal filature technology and a spinning machine for producing viscose filaments, which applies a viscose filament semi-continuous centrifugal spinning technology for shaping one-ingot three-silks in a tube including that the solidification and decomposition of the glue and acid bath react in the way of shaping in the tube, in which, there are three viscose measure outlets for each ingot, three sets of candle filters, three nozzles, three shaping tubes and three centrifugal jars, which applies the new technology and new type of glu supply and winding device to realize the filament production efficiency 2-3 times of that of the original R535A(B) type.

The invention relates to an environment-friendly dredged sediment integrated mechanical deep-drying system. An input pipeline is communicated with a primary settling unit by a grating unit; the primary settling unit is communicated with a secondary settling unit by an overflow weir; the secondary settling unit is communicated with a first modulating unit by the overflow weir; the first modulating unit enters a tertiary settling unit by a first chemical adding unit; upper-layer residual water in the tertiary settling unit is connected with a residual water purifying unit by a water decanter; and settled mud on the bottom is connected with a mechanical dehydrating unit by a mud pump on the bottom of the tertiary settling unit. By combining dredging engineering practical conditions with dredged sediment at home and abroad, the system disclosed by the invention is integrated with a series of functions such as bottom mud dehydrating, drying, silt-grading, residual water treating, and the like, has characteristics of being less in floor area, great in treatment scale, small in environmental pollution, short in time limit for a project, high in economic benefits, and the like, and effectively solves difficulty in the conventional dredge yard.

The invention discloses an intelligent control indoor planting field system using an LED plant growth-promoting lamp as a background. The intelligent control indoor planting field system aims at meeting the demand for energy-saving, environment-friendly and intelligent planting and is characterized by comprising a growing rotation module, a plant growing box module, an LED light source module, a water supply module, an energy supply module, a central control module and a user terminal. A user can check the plant growing situation through a mobile terminal and a PC terminal and meanwhile can adjust the light matching and strength, temperature, carbon dioxide concentration and moisture parameter of the plant growth-promoting lamp through the terminals so as to meet the growing demands of different plants.

The invention discloses novel spring-stepped scene-layered sewage treatment equipment and relates to the technical field of sewage treatment equipment. The sewage treatment equipment is composed of a grid well, an adjusting tank, an anaerobic tank, a water collection tank, a horizontal subsurface flow constructed wetland, surface flow constructed wetlands, an effluent water collection tank and water body purifying plants, wherein the anaerobic tank is arranged at the center of the adjusting tank; the horizontal subsurface flow constructed wetland is arranged on the upper layer of the anaerobic tank; the water collection tank is arranged at the center of the horizontal subsurface flow constructed wetland; several layers of surface flow constructed wetlands are sequentially arranged on the periphery of the horizontal subsurface flow constructed wetland; a layer of horizontal subsurface flow constructed wetland is also arranged on the periphery of the surface flow constructed wetlands; and the horizontal subsurface flow constructed wetland and the surface flow constructed wetlands are filled with constructed wetland padding, and water body purifying plants are planted therein. The novel spring-stepped scene-layered sewage treatment equipment disclosed by the invention has the advantages of novel and reasonable structure design and good using effect, the using cost can be effectively lowered, secondary pollution is avoided, the land occupation is saved, and the equipment is efficient, stable and maintenance-free.

The invention discloses an integrated energy-saving base station which comprises an air outlet (1), a pipe tower channel (2), an integrated frame (3), an integrated machine room (4), eight air inlets (5), a convection channel device (6) and a counter weight set (7), wherein the eight air inlets (5) are formed on the two sides of the integrated machine room (4). During running, equipment arranged in the integrated machine room (4) generates heat, the indoor temperature rises, the air pressure changes, the differential pressure is generated in the pipe tower channel (2), and a chimney effect is generated; air rises, flows, passes through the integrated machine room (4), the convection channel device (6) and the pipe tower channel (2), and is discharged from the air outlet (1); fresh air is supplied from the air inlets (5); and air movement in the pipe tower channel (2) can be improved due to the air movement at the top of a pipe tower, and a negative pressure area generated by an unpowered ventilation device mounted at the air outlet (1). A hot environment of the machine room can be improved by natural ventilation, and the energy consumption of an air conditioner can be reduced effectively.

Disclosed is an electric vehicle charging system based on wireless electric energy transmission. The electric vehicle charging system comprises a charging pile and a wireless electric energy receivingdevice; the charging pile includes a lifting control part, an automatic alignment device and a wireless electric energy emitting device. The lifting control part includes a signal acquisition module,a first signal processing module, a first microprocessor, a first driving module, a first execution module and a second execution module. The automatic alignment device consists of a signal emittingsystem and a signal receiving system. The wireless electric energy emitting device comprises a power supply port, a first rectifier, a first DC-DC converter, a high-frequency inverter, an emitting coil, a wired direct current charging module and a wired alternating current charging module. The wireless electric energy receiving device comprises a receiving coil, a second rectifier, a second DC-DCconverter and a battery access port. According to the electric vehicle charging system, a wind-solar complementary power generation system is adopted as a power supply source of the electric vehicle charging pile, and the problem is solved that the power generation voltage output by wind-solar complementary systems and other new-energy power generation systems is low.

The oil-containing restaurant waste water purifying treatment apparatus includes one electrically heating system, one frequency varying vibrating magnetic field, one corrugated-flat plate oil-water separating tank, one ultrasonic vibration generator, one ozone generator, one filtering carbon tank and one ultrafiltering membrane filter with one back flushing unit. Oil-containing restaurant waste water is treated successively through initial filtering, vibration treating in frequency varying vibrating magnetic field, oil-water separating, ozone treating and ultrasonic vibration treating. The apparatus has high waste water treating quality, continuous separation, high waste water treating capacity, small size, low cost and other advantages.

The invention relates to a ceramic raw material independent-grinding centralized preparation technique and device and belongs to the technical field of ceramic raw material preparation. The ceramic raw material independent-grinding centralized preparation technique comprises the steps that firstly, various single kind of raw materials are crushed independently through a crusher; secondly, the crushed single kind of raw materials are conveyed to a ball mill for continuous ball milling; thirdly, the raw materials subjected to ball milling and mud are conveyed into a slurry mixing and storing tank according to a formula to be evenly mixed; and finally, evenly-mixed finished slurry is conveyed to a drying tower to be dried. The ceramic raw material independent-grinding centralized preparation device comprises a hard material treatment device, a mud treatment device and a slurry drying device. By the adoption of the technique and device, the existing disorder situation of raw materials for processing ceramic can be avoided, and the technique and device have remarkable economic benefits.

The invention discloses a rainwater wash-out ecological toilet based on solar power generation. The rainwater wash-out ecological toilet based on solar power generation comprises a rainwater filtering and collecting system, a solar power generation and supply system, a PLC control system, an integrated public toilet body, a combined sewage treatment system and a composite artificial wetland system which are all sequentially connected. The solar power generation and supply system is arranged on the top of the integrated public toilet body and used for supplying power to the rainwater filtering and collecting system, the PLC control system, the integrated public toilet body, the combined sewage treatment system and the composite artificial wetland system. The rainwater filtering and collecting system is used for collecting rainwater and filtering and processing the rainwater, and then the rainwater can be supplied to the toilet. The combined sewage treatment system and the composite artificial wetland system are connected in series for use and used for processing drained water of the toilet. The PLC control system is used for performing automatic control over the whole system. The toilet supplies power through clean energy. The drained water of the toilet can be effectively processed, maintenance cost is low, and the ecological toilet has very important ecological benefits, economic benefits and social benefits.

The invention discloses a parking device, which comprises a parking platform and a lifting appliance. The parking device is characterized by further comprises a main rack, movable supporting columns and roller components. The main rack comprises a front-side support, a rear-side support and a connecting crossbeam. The front-side support and the rear-side support are arranged parallelly mutually from front to back, the connecting crossbeam is fixedly connected between the rear side of the upper portion of the front-side support and the front side of the upper portion of the rear-side support, and both the front-side support and the rear-side support are seated and fixedly connected onto a foundation during usage. Two ends of one side of the parking platform are respectively hinged on the corresponding movable supporting columns, and two ends of the other side of the parking platform are respectively arranged on the front-side support and the rear-side support correspondingly via the corresponding roller components. The parking platform is driven by a front-side winch and a rear-side winch of the lifting appliance to be capable of translating from a lower side position on the lower portion of the main rack to an upper side position on the upper portion of the main rack, or translating from the upper side position to the lower side position.

The invention relates to the technical field of air-conditioning systems for data computer rooms, and discloses a natural cooling system adopting reverse-flow air heat exchange for a data computer room. The natural cooling system is applied to the data computer room, and comprises a heat exchanger and a server cabinet, wherein the server cabinet is arranged in the data computer room; the heat exchanger is a reverse-flow air heat exchanger, and comprises an inner circulating air duct, an outer circulating air duct, and a heat exchange core used for carrying out heat exchange on air in the inner circulating air duct and the outer circulating air duct; and flow guide fans are arranged at an air outlet port of the inner circulating air duct and an air outlet port of the outer circulating air duct respectively. The natural cooling system further comprises a compressor refrigeration system, wherein the compressor refrigeration system comprises an indoor unit and an outdoor unit; the indoor unit is connected with the outdoor unit through a refrigeration pipeline; and an air outlet port of the indoor unit communicates with a space below a raised floor. The natural cooling system disclosed by the invention carries out refrigeration by virtue of the reverse-flow air heat exchanger in low-temperature seasons and carries out refrigeration by virtue of a compressor system in high-temperature seasons. The whole system adequately utilizes a natural cold source of outdoor fresh air for indirect heat exchange, thus saving energy and increasing efficiency.