A kind of novel air-dissolving apparatus
The utility model relates to a kind of novel air-dissolving apparatus; Be mainly used in the generation of microbubble in the dissolved air flotation, the paper pulp fiber that can be applied to water-oil separating, the paper industry of petrochemical industry, metallurgy, machining class reclaims, the concentrating of sludge from wastewater treatment plant concentration basin excess sludge, fields such as recovery that the city tap-water factory dry season is removed algae and rare metal.
Dissolved air flotation is a kind of time-honored solid-liquid, liquid-liquid isolation technics, and its cardinal principle is: under condition of high voltage, with air in certain amount formation high pressure soluble in water dissolved air water; Then through the pressure-reducing valve sudden pressure reduction, contact with former water mix after, the entering flotation tank; Discharge the microbubble of high density, dispersion after the dissolved air water decompression at once, adhere to pollutant surfaces such as elaioleucite in the former water, suspension, form " water-gas-particle " three-phase amalgam (proportion is less than 1.0); Make its buoyancy greater than gravity and rising resistance, thereby float, form foam to the water surface; Collect by scum machine then and discharge, realize the separation of pulp water.
As far back as nineteen thirty, the Sweden paper mill once tried air is dissolved under outside casing spare in the water treatment of plain boiled water, delivered and caused enough attention but above-mentioned experimental result is all unexposed.
The last century is before the sixties, and the air flotation technology development is slower, the rarely found report that its research and application are arranged, and basic reason is that the technology of making microbubble does not reach a standard.Mainly adopted dispersion air air supporting method at that time; Be used for the waste water of the little material of proportions such as water supply plant or oil-containing, fat, fiber is handled; But the bubble of its generation is fine inadequately, and is very poor to the adhesive capacity of particle, also can produce serious turbulent flow simultaneously and crashes flco.
The beginning of the seventies; Air flotation technology develops rapidly; People begin one's study through pressuring method that air is soluble in water; Decompression discharges the method that obtains microbubble then, has derived a series of dissolved air flotation then, such as full pressurized dissolved air flotation method, partial reflux dissolved air flotation, shallow gas float glass process and vacuum air supporting method.Except that said method, also have electrolytic gas float glass process, cavitation air flotation method, Ni Keni dissolved air flotation etc.
Mainly account for the market leading position at present with dissolved air flotation; Especially the most extensive with the application of partial reflux dissolved air flotation, its air-dissolving apparatus generally utilizes air compressor machine compressed air or water sprayer to suck air, after the employing centrifugal multistage pump multiple centrifugal pump is pressurized to 0.43-0.58MPa with recirculation water; Squeeze in the dissolving in the lump with compressed air; Realize that G&W fully mixes, reach the purpose of dissolving gas, molten tolerance depends on liquid level and the operating pressure of dissolving in the dissolving.Because the dissolving volume is comparatively huge, and internal pressure is in dynamic change, needs the special messenger to supervise during operation, can't realize automation control.In addition; The generation of this method microbubble mainly relies on the decompression of dissolved air release to discharge, and the microbubble particle diameter that is produced is at the 40-100 micron, and is limited for the adsorption capacity of small suspension; When handling high turbidity, high oil-polluted water; Cause the obstruction of dissolving and dissolved air release easily, influence treatment effect, also safeguard and brought very big difficulty to regular job.In addition, the long-time high-speed cruising wearing and tearing of air compressor machine, centrifugal multistage pump multiple centrifugal pump are more serious, and the noise that the noise of equipment operation and tank body vibration are sent has produced certain influence to surrounding environment.
Summary of the invention
The utility model provides a kind of novel air-dissolving apparatus, mainly is made up of water inlet pipe, control valve, screw pump, microbubble generator, counterbalance valve, pressure transmitter, gas flowmeter, outlet pipe etc., and principal character has:
(1) water inlet pipe connects control valve one side, the water inlet of another side joint screw pump of control valve, and the delivery port of screw pump connects the water inlet of microbubble generator, and the delivery port of microbubble generator connects the influent side of counterbalance valve, and the water outlet side of counterbalance valve picks out water pipe.
(2) microbubble generator is a stainless steel, pressure transmitter is housed, intake pressure 0.7-1.1MPa during operation, discharge pressure 0.5-0.7MPa respectively on its water inlet and the water outlet pipeline section.
(3) screw pump is multistage single-screw (single screw) pump, and the ratio of the water yield that metered flow and need are handled is 20-25%, and lift 12bar adopts the counter-rotating operation, and is furnished with dried running protection apparatus, and the rotating speed through the variable-frequency control technique control pump is lower than 300rpm.
(4) the counterbalance valve range of regulation is at 0.3-1.0MPa, the microbubble particle diameter that discharges≤5 μ m.
(5) outlet of gas flowmeter adopts plastic flexible pipe to be connected on the pipeline section between control valve and the screw pump, and maximum stream flow is 30-35% with the ratio of screw pump metered flow.
The utility model is compared with the air-dissolving apparatus of traditional air-dissolving air-float, and the major technique innovative point is:
(1) adopts screw pump as pressurized equipment, substitute traditional centrifugal multistage pump multiple centrifugal pump, and be a whole set of unique running device; Can be through the rotating speed of variable-frequency control technique control pump; Can either keep the internal system pressure stability, prolong stator service life again, can effectively reduce operation energy consumption simultaneously.
(2) core of system is dissolved gas equipment---microbubble generator; Can install according to handling water yield combination in any; Substituted traditional air compressor machine and huge dissolving, do not have to have stopped up, no fouling, corrosion-resistant, the maintenance work all the year round of having avoided dissolving shakes the noise that is sent during with operation.
(3) substitute traditional dissolved air release with counterbalance valve,, avoided the problem of traditional dissolved air release easy blocking as the decompression release of dissolved air water.
(4), be easy to keep the stable of operating pressure with the accurate molten tolerance of metering system of gas flowmeter.
(5) through the complete PLC control system of a cover, realize system's self-protection, can carry out internet communication with Central Control Room simultaneously, realize remote monitoring, need not the personal management.
The beneficial effect of the utility model is: this device can be applicable in full pressurized dissolved air flotation method or the partial reflux dissolved air flotation; The microbubble that produces has characteristics such as particle diameter little (≤5 μ m), rising is stable, absorption affinity is strong, life period is long; Improved the treatment effeciency of air flotation technology so greatly; Reduce the floor space that the air supporting method is used, realized the automation control of air-dissolving apparatus, effectively reduced the use amount of chemical agent simultaneously; Deficiencies such as noise is big when overcoming existing air-dissolving air-float equipment operation, energy consumption is high, serious wear, regular job are difficult in maintenance are a cover efficient, energy-conservation, environmental protection water treatment facilities that automaticity is higher truly.
Description of drawings
Below in conjunction with accompanying drawing and embodiment the utility model is further specified.
Accompanying drawing is the technological process schematic diagram of the utility model.
1. water inlet pipes in the accompanying drawing, 2. control valve, 3. gas flowmeter, 4. screw pump, 5.1# pressure transmitter, 6. microbubble generator, 7.2# pressure transmitter, 8. counterbalance valve, 9. outlet pipe.
The specific embodiment
The utility model relates to a kind of novel air-dissolving apparatus of air supporting method, and the specific embodiment is following: (1) connects water inlet pipe 1 and former water, and outlet pipe 9 is with after the flotation tank water inlet pipe links to each other, and standard-sized sheet control valve 2 transfers to the minimal pressure state with counterbalance valve 8; (2) start screw pump 4, former water begins to be entered in screw pump 4 and the microbubble generator 6 by water inlet pipe 1, notices that the pressure display of observing on 1# pressure transmitter 5 and the 2# pressure transmitter 7 raises gradually; After pressure stability, slowly turn control valve 2 down, make and form certain negative pressure between control valve 2 and the screw pump 4 in the pipeline section; Ball valve on the crack gas flowmeter 3, whether have micro-air get into, if not if observing; Then should close the ball valve on the gas flowmeter 3, continue to turn down the aperture of control valve 2, repetitive operation; By the stable gas flowmeter 3 that sucks, adjustments of gas flowmeter 3 control handles are until the air inflow of needs until air; (3) slowly regulate look nut on the counterbalance valve 8, the pressure in the microbubble generator 6 are raise gradually, keep pressure indication on 1# pressure transmitter 5 and the 2# pressure transmitter 7 respectively to 0.7-1.1MPa and 0.5-0.7MPa; (4) be continuous milky milk shape near the observation outlet pipe 9, discharge in flotation tank, spreading of a large amount of microbubbles, promptly realized molten gas process.