214results about How to "Guaranteed long-term stable operation" patented technology

The invention relates to a genetic-algorithm-based trajectory planning optimization method for a mobile mechanical arm. According to the technical scheme, the method comprises the following steps of first establishing a forward kinematic model and an inverse kinematic model of a multi-degree-of-freedom mobile mechanical arm; then fitting a joint trajectory by adopting a composite curve of a quartic polynomial mathematical model and a quintic polynomial mathematical model, and calculating solutions of the corresponding mathematical models according to a linear constraint equation; next selecting a trajectory optimization target according to the principles of shortest motion time, minimum spatial motion distance and less than or equal to maximum set joint torque of the mobile mechanical arm; and finally globally optimizing the optimization target by utilizing a genetic algorithm to obtain an optimal trajectory curve of an end actuator of the mechanical arm. According to the method, the trajectory planning efficiency and the tracking accuracy of the mechanical arm are improved, and the problems of real-time trajectory planning of the mobile mechanical arm and trajectory planning optimization and control of the mechanical arm in an uncertain environment are also solved; and the trajectory planning optimization method for the mobile mechanical arm is effective.

The invention discloses a recycling method of high brine waste water based on forward osmosis. The method comprises the following steps: firstly, concentrating high brine waste pretreated through a forward osmosis membrane element, wherein water in waste water enters into a driving liquid from a raw material side of a forward osmosis membrane; and then, concentrating, dehydrating and regenerating the diluted driving liquid obtained through one or more of a membrane distillation membrane element, a membrane distillation evaporation assembly or a low temperature multi-effect evaporation assembly, wherein regenerated driving liquid is recycled in the process of returning to forward osmosis. The method is widely applicable for the type of waste water, and has the advantages of long-term stable operation and low treatment cost.

The invention discloses efficient heterogeneous catalytic oxidation ferric-carbon micro-electrolysis packing and a preparation method thereof. The packing is prepared from the following raw materials in parts by weight: 45-65 parts of pure iron powder, 10-25 parts of cast iron powder, 2-8 parts of graphite powder, 5-15 parts of active carbon powder, 2-10 parts of copper powder, 2-10 parts of manganese powder, 2-10 parts of aluminum powder, 2-10 parts of fine wood bits, 1-6 parts of sodium silicate, 1-6 parts of sodium borate, 2-6 parts of pyrite dust and 5-15 parts of an adhesive. The efficient heterogeneous catalytic oxidation ferric-carbon micro-electrolysis packing disclosed by the invention is prepared by taking heterogeneous metal alloy with high potential difference as a catalyst and using a high-temperature micropore roasting technology and has the characteristics of heterogeneous metal and ferric-carbon integration, micropore framework type alloy structure, large specific surface area, low density, strong activity, high current density and the like; organic wastewater is treated so that COD, ammonia nitrogen and total phosphorus can be efficiently removed, the chroma can be reduced, the biodegradability can be improved, the treatment effect is extremely stable, and the phenomena of packing passivating, hardening and the like caused in the operation process can be avoided.

The invention provides a purification method of an organic waste gas, in particular to a purification method of organic water gases containing aldehydes, ethylene glycol, PTA dust and so on, polyester waste gas processing method for example. After being discharged from the discharge port, polyester waste gas firstly enters into an adsorption homogenization tank filled with porous solid adsorbent, and then is processed catalytic combustion treatment. In adsorption homogenization tank, the components of ethylene glycol and so on are fully absorbed, and the PTA dust is filtrated, and at the same time the concentrations of components of aldehydes and so on are homogenized under adsorption-desorption effect. The concentration homogenized waste gas enters into catalytic combustion reactor, and is totally oxidized into carbon dioxide and water under the effect of catalyst, and standard-met discharge is achieved. The function of the special typed active carbon used in the invention is not condensation but adsorption, filtering and homogenizing. The invention can prolong the service life of catalytic combustion catalyst, has good purification effect, safe and stable arrangement.

The present invention provides a conductive diamond electrode having: a conductive substrate; a coating layer formed on a surface of the conductive substrate, the coating layer containing one of a metal and an alloy each including at least one of niobium and tantalum; and a conductive diamond layer formed on a surface of the coating layer, and a process for producing the conductive diamond electrode.

The invention provides a plate type air preheater with glasses as heat exchange plates, belonging to the technical field of heat exchangers. The plate type air preheater comprises an air preheater frame, the air preheater frame comprises an upper cover plate (10), a lower bottom plate (11) and a stand column (5) and is internally provided with a plurality of heat exchange plates (1) which are correspondingly placed in vertical direction; a sealing strip (4) is arranged between every two heat exchange plates (1) which are adjacent in vertical direction; the sealing strips (4) are mutually staggered at 90 degrees and form a plurality of sealing fluid channels which are adjacent and mutually staggered at 90 degrees by being placed in a staggered way so as to respectively form hot fluid channels and cold fluid channels; rectangular glass plates are adopted as the heat exchange plates (1), and the glass can be silicon-boron glass and boron-free low-alkali glass or quartz glass; and supporting strips (2) which are rectangular or S-shaped nonmetal plate bars are arranged among the fluid channels formed by the upper and lower heat exchange plates (1). The invention has dew point corrosion resistance, efficiently recovers the low-temperature exhaust heat of smoke and can reduce the temperature of discharged smoke and enhance the efficiency of a heating furnace.

The invention discloses an air-source heat pump device integrating cool and warm air conditioning and water heating in the cold area, which belongs to the technical field of refrigeration air conditioner. The device consists of two high and low pressure compressors, a flash evaporator, a defrosting coil pipe, a flash gas superheated coil pipe, a compressor heat recovery coil pipe, a low pressure gas supply pressure pipeline and other parts which are connected through pipelines. The device is characterized in that the two high and low pressure compressors in the system have three modes of separate operation, parallel operation, and two-stage compression combined operation; and the two compressors are matched with a four-way electromagnetic directional valve, a three-way electromagnetic valve and an electromagnetic valve to form a refrigeration mode, a heating mode, a hygienic hot water mode and a refrigeration and hygienic hot water combined operation mold. The air-source heat pump device has the advantages that the device not only can refrigerate and produce hygienic hot water while refrigerating in summer; and under the microthermal climate in winter, the device can run stably to provide the heat needed by indoor heating and hygienic hot water, thereby realizing the integrated cool and warm air conditioning and water heating. The device which is used in a house in the cold area has wide popularization and application space and energy-saving significance.

The invention discloses a forced water circulation high-capacity hot water boiler of a circulating fluidized bed, which relates to a hot water boiler of a fluidized bed, and aims to ensure water circulation safety and power failure protection of a high-capacity hot water boiler of a circulating fluidized bed. A water supply distribution header is connected with lower coal economizers; the lower coal economizers, middle coal economizers and upper coal economizers are sequentially connected with one another; the upper coal economizers are connected with a coal economizer upper header; the coal economizer upper header is connected with a collection water bag by a coal economizer coating pipe; the collection water bag is connected with water cooling wall lower headers by a descending pipe; the water cooling wall lower headers are connected with a hearth water cooling wall; the hearth water cooling wall is connected with water cooling wall upper headers; the water cooling wall upper headers are connected with a boiler cylinder by extraction pipes; the water supply distribution header is connected with a separator water cooling sleeve by a water cooling sleeve water intake pipe; the separator water cooling sleeve is connected with the boiler cylinder by a water cooling sleeve water outlet pipe; the boiler cylinder is connected with the water cooling wall lower headers by communicating pipes, and is connected with the water supply distribution header by a power failure water supply pipe. The forced water circulation high-capacity hot water boiler provided by the invention is applied to large concentrated heat supply and warming.

A processing method of crylic acid and ester heavy components includes the following steps: A) conducting distillation splitting on the crylic acid or the ester heavy components to enable the crylic acid or the ester heavy components to be converted into crylic acid steam; B) condensing and collecting the crylic acid steam; and C) purifying the collected crylic acid. The processing method is simple in process flow, high in recycle rate, high in purity, stable in long-term operation, capable of bringing high economical and environment benefits to society and worth popularizing in the market.

The invention provides a dual-compressor rapid cooling low temperature refrigeration system. By means of the refrigerant circular path which is formed through pipeline connection, the dual-compressor rapid cooling low temperature refrigeration system comprises a compressor unit, an oil separator unit, an air-cooled condenser unit, a dryer unit, a regenerator unit, a throttling unit, an evaporator unit, a regenerator unit, a gas-liquid separator unit, a regulating valve and a control unit; the compressor unit comprises a first compressor and a second compressor which are connected in parallel, and the input end of the first compressor and the input end of the second compressor are connected with the gas-liquid separator unit through a distributor. The invention provides a dual-compressor rapid cooling low temperature refrigeration method. The discharge pressure, temperature and power of the compressor unit and the outlet temperature of the evaporator unit are collected through the control unit, control commands are outputted to the throttling unit, the regulating valve and the compressor unit, so that the refrigeration system can run efficiently and stably for a long time; meanwhile, when one of the compressors breaks down, the normal operation of the refrigeration system can still be guaranteed.

The invention provides a powdered coal combustor for an entrained-flow bed gasification furnace. The powdered coal combustor comprises a central pipe and a peripheral pipe concentrically surrounding the central pipe. The cross section of a central pipe spray nozzle straight section is a sharp acute angle, two sides (namely the central pipe spray nozzle straight section and a central pipe spray nozzle outer-side slanted side corresponding to the straight section) of the acute angle are larger in length, guide pieces are arranged above the central pipe spray nozzle straight section, and a spiral guide chamber is arranged on a powdered coal channel defined by the central pipe and the peripheral pipe. The powdered coal combustor can effectively reduce the high-temperature radiation area and strength at the position of a central pipe spray nozzle, the service life of the powdered coal combustor can be prolonged, dismounting and maintenance of the spray nozzle are facilitated, the effect of mixing powdered coal and an oxidizing agent can be improved, the long-period stable operation of powdered coal gasification is achieved, and the cost for powdered coal gasification can be reduced.

The invention discloses a method for producing an iron carbon micro-electrolysis filler from nonferrous metal waste ore slag, which comprises the following steps: grinding copper ore slag and lignite, and passing through a 100-120-mesh sieve; carrying out magnetic separation to remove impurity silicon dioxide powder; adding assistants; injecting into a squeeze film to obtain strips, and cutting into cylindrical blanks; drying; heating the blanks; and carrying out compression molding. The product disclosed by the invention has the characteristics of integrated iron carbon, large specific area, light specific gravity, strong activity, high current density, high efficiency for treating various types of sewage, and the like, and has the catalyst / micropore-fused alloy structure. The high-activity nonferrous metals, such as Cu and the like, contained in the novel product change the phenomena of filler passivation, hardening and the like in the old product operational process, and ensure the long sustained action period of the micro-electrolysis reaction process.

The invention belongs to the technical field of water treatment, and in particular relates to a membrane pollution intelligent diagnosis and early warning decision making system of a hollow fiber device. An online remote control module, a membrane pollution prediction module, a membrane pollution evaluation and early warning classification module, a membrane system abnormal circumstance intelligent diagnosis and decision making module, and an information resource management and human-computer interaction module are systematically integrated to build the membrane pollution intelligent diagnosis and early warning decision making platform, wherein the modules form the software platform of the system, and intelligent instruments on the hollow fiber membrane device such as an electromagnetic valve, a pneumatic valve, a flowmeter and turbidimeter, a pH meter and a hardness meter, and a PLC, a server, a client side and an industrial Ethernet form the hardware platform of the system. The system applicable for a plurality of hollow fiber membrane devices has the advantages of realizing convenient data exchange with an automatic system in the conventional device and improving the economic benefit of the integral membrane method separation process along with easy realization and wide application and popularization range.

[Problems] The liquid pressure of an anode chamber in a two-chamber ion exchange membrane electrolytic cell using a gas diffusion electrode are different among one another depending on depths so that the liquid pressures are applied on an anode or an ion exchange membrane, thereby introducing damage or deformation of the elements.[Means for Solving] A cushion material 10 is accommodated between a cathode gas chamber back plate 9 and a gas diffusion electrode 7 of an ion exchange membrane electrolytic cell 1 such that a repulsive force of the cushion material at the bottom part of the cathode gas chamber is larger than that at the top part. The excessive pressure applied to an ion exchange membrane is suppressed to prevent the generation of scratches or the like by decreasing the repulsive force of the cushion material toward the top in accordance with a differential pressure between an anode chamber pressure and a cathode gas chamber pressure.

The invention relates to a design of a Roots pump, in particular to a rotor of a Roots dry vacuum pump which discharges directly into atmosphere and processing technology thereof. The processing technology substitutes a waist arc for an involute to design a rotor block, the rotor block is separately processed and then assembled with a spigot shaft. The processing steps are as follows: (1) processing the rotor block: a ductile cast iron bar is selected as roughcast; processing method: firstly processing the outer surface and the two end surfaces of the bar, incising the bar according to the thickness of the rotor block, then processing other two surfaces (outer circular surface and inner circular surface) of the rotor block, finally incising the bar into the rotor block with needed thickness according to application requirements; (2) joining two rotor blocks and a pin roll into a whole via a pin hole. The invention has the advantages of simple processing technology, low cost, high versatility of parts, suitability for IC equipments, etc.

The invention relates to a pulse width modulation based cathode protection method. The pulse width modulation based cathode protection method comprises the following steps: firstly, connecting a buried pipeline facility by adopting a pulse width modulation polarization power supply; secondly, setting a cathode protective potential to a predetermined value; thirdly, generating a pulse width modulation signal according to cathode protective potential value; fourthly, driving the pulse width modulation polarization power supply by the pulse width modulation signal; fifthly, measuring output voltage of the pulse width modulation polarization power supply, measuring output current of the pulse width modulation polarization power supply; sixthly, measuring cathode protective potential, relative to a reference electrode, of the buried pipeline facility; a pulse width modulation based cathode protection device is characterized in that the pulse width modulation polarization power supply is connected with an output current measuring device and an output voltage measuring device, the pulse width modulation polarization power supply is connected with a buried facility, an auxiliary anode and an on-off controller, a control circuit is connected with a feedback signal controller by virtue of a protective potential setting device, and a cathode protective potential measuring device is connected with a buried reference electrode by virtue of a copper sulphate reference electrode impedance converter, so that size is small and control accuracy is high.

The invention relates to the technical field of environment protection, in particular to a biology floating island capable of automatically rising and falling. The island comprises a floating island body, an inside-water stand column, a shoreside rope fixing pile, a pulley, a bidirectional motor, at least one fixing end steel wire rope, a shoreside stand column and at least one traction end steel wire rope. The floating island body is provided with a frame structure. One end of each fixing end steel wire rope is fixed to the top end of the inside-water stand column, and the other end of each fixing end steel wire rope is connected with the frame structure. One end of each traction end steel wire rope is connected with the frame structure, and the other end of each traction end steel wire rope is fixed to the fixing pile or connected with the bidirectional motor. The pulley is arranged at the top end of the shoreside stand column. The position of the biology floating island in a river channel water body is controlled by the bidirectional motor and the steel wire ropes; the bidirectional motor is used in the adjusting process of the biology floating island, labor is saved, and the island is convenient to operate and easy to obtain. In addition, the biology floating island is scientific in structural setting, stable in force bearing of each layer, and capable of normally working, rising and falling under the severe weather conditions.

A copper powder that is excellent in weatherability and adapted for use in conductive paste is provided that contains 10-20,000 ppm, preferably 100-2,000 ppm, of Sn. The copper powder is particularly preferably one having an average particle diameter DM of 0.1-2 μm and, further, one wherein the particle diameter of at least 80% of all particles is in the range of 0.5 DM-1.5 DM. This copper powder can be produced, for example, by precipitating Cu metal by reduction of Cu ions in the presence of Sn ions.

The invention discloses a flameless combustion chamber for a Stirling engine and an implementation method of the flameless combustion chamber. The flameless combustion chamber comprises a combustion chamber housing, a combustor and a heat exchanger; the housing consists of an upper housing part and a lower housing part; an exhaust pipe is arranged at the top of the housing; a heat exchanger barrelis arranged at the bottom of the housing; the lower housing part is connected with the top of the heat exchanger barrel into a whole; the top of the heat exchanger barrel, the lower housing part andthe upper housing part form a combustion chamber space; a hot cavity of the Stirling engine is formed in the lower end of the heat exchanger barrel; the top of the heat exchanger barrel separates thecombustion chamber from the hot cavity; the combustor and the heat exchanger are arranged in the housing from the top to the bottom sequentially; the heat exchanger comprises a circle of heat exchangepipes arranged in a reverse-U-shaped manner; and one ends of the heat exchange pipes communicate with the hot cavity of the Stirling engine, and the other ends of the heat exchange pipes communicatewith a reheater, thus a circuiting working medium system is formed. The implementation method comprises the step that the combustion chamber is used for combustion. The flameless combustion chamber and the implementation method have the characteristics that the combustion chamber is uniform in temperature, the combustion efficiency is high and the safety and reliability are achieved. The flamelesscombustion chamber is particularly suitable for the Stirling engine for use.

The invention discloses a preparation method of a micro-electrolysis filling material. The method comprises the steps of mixing the raw materials including scrap iron, activated carbon and dispersant, calcinating the mixture at the temperature ranging from 1080 DEG C to 1180 DEG C and under oxygen-free conditions; cooling, crushing and screening, wherein the consumed scrap iron accounts for 60 to 70% of the total mass of the raw material, the consumed activated carbon accounts for 20 to 30% of the total mass of the raw material, and the consumed dispersant accounts for 5 to 10% of the total mass of the raw material. The micro-electrolysis filling material has remarkable effects on removing wastewater COD (Chemical Oxygen Demand) and lowering the chromaticness, can improve the biodegradability of wastewater well, avoids inactivation and hardening during treatment process, and is stable and effective during long-term operation, so that the reaction rate is high and only 30 to 60 minutes is required to treat industrial wastewater; the micro-electrolysis filling material is relatively lower in iron content, so that the specific weight is greatly reduced and convenience is provided for load, transportation and use; the application range of the activated carbon is expanded, so that convenience is provided for purchase and production; and a wide variety of dispersants can be used in the method and can be adjusted according to different kinds of wastewater, thereby having a better treatment effect on all kinds of wastewater.

The invention discloses a metal rigidity seal ball valve which comprises a valve, a valve seat, a valve stem and a ball. The ball is positioned in a ball cavity in the valve; the valve seat comprisesa left valve seat and a right valve seat, the left valve seat and the right valve seat are symmetrically arranged on two sides of the ball, and scraper mechanisms are arranged at the positions, whichare butted to the ball, of the valve seat; seal surfaces between the valve seat and the valve are in the shapes of multiple levels of steps which are matched with one another, and a first sealing assembly is arranged between every two corresponding seal surfaces; each first seal assembly comprises a first elastic component, a clamping component and a first seal ring; the clamping components are provided with L-shaped axial sections, two ends of each first elastic component are butted to the valve and a vertical arm of the corresponding L-shaped clamping component, a corner of each L-shaped clamping component is clamped on one of the levels of steps of the corresponding seal surface of the valve seat, the first seal rings are mounted between the tail ends of transverse arms of the L-shapedclamping components and the seal surfaces of the valve seat, and metal protection layers are arranged on the seal surfaces of the valve and are positioned on the outer sides of the first seal rings. The metal rigidity seal ball valve has the advantages that seal structures on the seal surfaces are improved, accordingly, seal effects can be enhanced, the service lives of seal components can be prolonged, elastic components can be protected, and the metal rigidity seal ball valve is particularly applicable to working conditions with crude oil used as a medium.

The present invention discloses a gas distribution structure for a distillation column. Pressure drop adjusting column tray assemblies are arranged in a left mass transfer region and a right mass transfer region along a column height direction. The gas distribution structure includes column trays, gas-rising pipes, downcomers and cover hoods, wherein a gas flow meter is arranged in a pipe of any gas rising pipe; a feeding port and a liquid collecting port are formed in a column wall; a liquid flow meter, an adjusting valve and a circulation pump are arranged on a circulation pipeline between each liquid collecting port and each feeding port; technological parameters are transmitted to a control system; and the circulation pumps and the adjusting valves are controlled by the control system

A method of manufacturing a semiconductor device provides a semiconductor device with a gallium-nitride-based semiconductor structure that allows long-term stable operation without degradation in device performance. After formation of an insulation film on a surface other than on a ridge surface, an oxygen-containing gas such as O2, O3, NO, N2O, or NO2 is supplied to oxidize a p-type GaN contact layer from the surface and to thereby form an oxide film on the surface of the p-type GaN contact layer. Then, a p-type electrode that establishes contact with the p-type GaN contact layer is formed by evaporation or sputtering on the oxide film and on the insulation film. Heat treatment is subsequently performed at temperatures between 400 and 700° C. in an atmosphere containing a nitrogen-containing gas such as N2 or NH3 or an inert gas such as Ar or He.

The invention particularly discloses a switched reluctance motor fractional order sliding mode controller design method. The method is characterized by comprising the following steps: based on an electromechanical contact equation of the switched reluctance motor, a switched reluctance motor model is built; based on the switched reluctance motor model, switching manifold surface design is carriedout; a Lyapunov function is used to verify the stability of the fractional order sliding mode control, and a fractional order sliding mode control law meeting an approximation condition is thus designed; parameters in the fractional order sliding mode control law are tuned; and a fuzzy inference algorithm is used to tune a fractional order sliding mode control switch gain epsilons. By using the characteristic of slowly transmitting energy with the fractional order of one more order r degree of freedom, the chattering problem of the traditional sliding mode control on the switching manifold surface can be weakened, the system has strong robustness towards parameter changes and outer disturbance, and when the motor operates at a low speed, torque pulsation can be effectively lessened, and the noise of the switched reluctance motor is weakened.

The invention provides a washing machine and a control method thereof. The washing machine comprises a washing cylinder, a water inlet pipeline and a laundry detergent automatic feeding device. The water inlet pipeline is provided with an inlet valve used for conducting the water inlet pipeline, and the water inlet pipeline is configured in a way that during the water feeding period of the washing machine, the water inlet pipeline provides laundry water for the washing cylinder. The laundry detergent automatic feeding device is configured in a way that after the water inlet pipeline is conducted, the laundry detergent automatic feeding device is controlled to pour laundry detergent into the washing cylinder. According to the invention, a control method that the laundry water is poured into the washing cylinder first, then the laundry detergent is poured into the washing cylinder is employed, the laundry detergent does not deposit in a water discharge pipeline between a water outlet and a drainage pump of the washing cylinder, the failure rate of the drainage pump can be reduced, and the fact that the washing machine operates stably for a long time is guaranteed.

The invention provides a metal carbon tube component for purifying wastewater. The metal carbon tube component comprises a metal disk and a central tube which is arranged in the inner cavity of the metal disk, wherein a plurality of first through holes used for making wastewater flow into the metal disk are radially formed in the side wall of the central tube; an electrocatalytic material is filled between the outer wall of the central tube and the inner wall of the metal disk; and a plurality of second through holes are axially formed in the disk surface of the metal disk. Due to a structure of flowing anodes and central water distribution, the metal carbon tube component is provided with a channel with a great specific surface area and uniform water flow and gas flow, so that wastewater treatment has higher current density and better catalytic reaction effect. The invention also provides an electrocatalytic oxidation device. The electrocatalytic oxidation device comprises a plurality of metal carbon tube components which are overlapped. Each component is arranged in the inner cavity of a shell, an anode pipe passes through the central tube; both ends are fixed by a support frame respectively and are closed; and one end of the shell is provided with a water inlet and a gas outlet, and the other end of the shell is provided with a water outlet and a drain outlet. The device integrates multiple functions into a whole, has low treatment cost and a good effect of removing organic pollutants.

The present invention discloses a method for extraction of humic acid, namely a method for two-stage ultrafiltration extraction of humic acid in a urban domestic waste sanitary landfill site and waste incineration power plant mixed leachate or a separate waste incineration power plant leachate MBR + NF membrane interception liquid, and the extraction method is advanced, practical, economic, simple in process and equipment, small in land occupation, free of secondary pollution, reliable and simple in operation, and suitable for extraction of humic acid in leachate MBR + NF membrane interception liquids with high salt content especially high divalent salt ion concentration.

The invention discloses a self-purification permeation-blocking system for a sponge city and belongs to the technical field of sponge cities. The permeation-blocking system comprises a main permeation-blocking system body and a self-purification system, a permeation mat formation is arranged in the main permeation-blocking system body, and the self-purification system comprises a self-purificationwell which is arranged nearby the main permeation-blocking system body; a back flushing porous pipe is laid on the lower layer of the permeation mat formation and connected to the self-purification well, a self-coupling device which is used for connecting a water outlet of a submersible pump with the back flushing porous pipe is arranged in the self-purification well, and a by-pass pipe which iscommunicated with the bottom of the main permeation-blocking system body is further arranged on the bottom of the self-purification well; during maintenance, the submersible pump is arranged in the self-purification well through the self-coupling device, and purified rainwater in the self-purification well is utilized for back flushing the permeation mat formation. The permeation-blocking system has the back flushing and self-purification functions, tedious maintenance work such as digging for soil replacement and filter material cleaning at regular time is not needed, and long-time stable running of the permeation-blocking system is guaranteed; the permeation-blocking system has the advantages that the system is simple in structure and convenient to implement and operate and saves the fund.

The invention discloses a heave deformation resisting construction method for foundation pit excavation above an existing tunnel. The heave deformation resisting construction method comprises the following steps that grouting pre-reinforcing is conducted on bottom layers around the existing tunnel and overlaying soil layers of the existing tunnel; primary slope putting and soil nailing shotcrete anchor supporting are constructed from the vertical upper part of the existing tunnel; primary slope putting and soil nailing shotcrete anchor supporting are constructed from the periphery of a foundation pit; foundation pit enclosure is constructed, and an internal support are erected; secondary slope putting and soil nailing shotcrete anchor supporting are constructed from reserved core soil; connecting grooves are dug; a grouting pipe curtain is constructed; and the reserved core soil is excavated segment by segment in a groove skipping mode. The heave deformation resisting construction method adopts the mode of combining formation pre-reinforcing with the grouting pipe curtain, the formation stiffness can be effectively increased, the formation is prevented from floating, thus the deformation value of the existing tunnel structure is controlled, long-term stable operation of the tunnel is ensured, and the application range is wide; and a method of reserving original core soil abovethe tunnel is adopted, it can be ensured that the overlaying gravity of the tunnel continuously exists, and interference to the stability of an underground structure is small.