CN1139076A

CN1139076A - Scale scouring method using the electric field between conductive liquid and metal container

Info

Publication number: CN1139076A
Application number: CN 96105292
Authority: CN
Inventors: 张来顺
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-05-31
Filing date: 1996-05-31
Publication date: 1997-01-01

Abstract

The scale scouring process includes filling heating container with conductive liquid, setting electrical field between heating container wall as one pole and conductive liquid as the other pole with scale as dielectric and boiling water in the heating container for certain time after eliminating electrical field and conductive liquid. When it is set, the electrical field breakdowns the combining layer between scale and the metal container wall. The said method has good scale scouring effect.

Description

Utilize the method for the electric field removing incrustation scale between conducting liquid and the metal vessel

The present invention relates to the incrustation scale clearance technique of water heating vessels, particularly a kind of method of utilizing the electric field removing incrustation scale between conducting liquid and the metal vessel.

For example drinking water boiler, boiler, kettle are after use for some time for the heating container of water, and wall of container just has incrusted deposit to adhere to, the incrustation scale of every mm thick, and its capacity of heat transmission is equivalent to the steel plate of 40 mm thick.Water-heaters such as boiler produce incrustation scale, not only reduce thermo-efficiency, and serious meeting causes the damage of water-heaters such as boiler, so incrustation scale should in time be removed.Existing incrustation scale clearance technique mainly adopts chemical process, the general hydrogenchloride that uses, caustic acid or other medicaments such as sulfuric acid, not only corrode metal heating such as boiler, also corrode sewer line, and cause environmental pollution, in the tap water boiler, after using the chemical cleaning method,, must use a large amount of clear water to wash for eliminating the harm of acid and resultant to human body.The chemical process scale removal is that incrustation scale is all dissolved, and it is many to consume medicament.In addition, its medicament corrosion water-heater of chemical cleaning, sewer line pollute water-heater, contaminate environment.

The purpose of this invention is to provide a kind of method of utilizing electric field between conducting liquid and the metal vessel to remove incrustation scale, dielectric principle in the electric field breakdown electric field is used to remove incrustation scale, need not any medicament, use and realize that the removing incrustation scale is effective, free from environmental pollution, and equipment is simple, and power consumption is few.

The object of the present invention is achieved like this: a kind of method of utilizing the electric field removing incrustation scale between conducting liquid and the metal vessel, and its principle of work and step comprise:

A. in being attached with the heating container of incrustation scale, inwall places conducting liquid;

B. between heating container wall and conducting liquid electric field being set, is a utmost point with wall of container, is another utmost point with conducting liquid, is dielectric medium with the incrustation scale, and this electric field carries out electric field breakdown to being soaked in the incrustation scale in the conducting liquid and the key coat of metal vessel wall;

C. remove electric field, remove conducting liquid after, in heating container, add the water boil certain hour.

The concrete steps of described method are:

The heating container wall that 1. will be attached with the metal material of incrustation scale connects an electrode, puts conducting liquid in this heating container, places a conducting plates in this conducting liquid, and this conducting plates does not contact with metal vessel and incrustation scale, and this conducting plates connects different in nature electrode;

2. to metal vessel and conducting liquid two different in nature electrifying electrodes, form electric field, its voltage between 35～300V, about 1-2 hour clamping time;

3. the conducting liquid in the heating container is emitted, hyperphoric new water is heated to the water boiling to container, and kept boiling state about 3-5 minute outside the container heating surface;

4. emit the water that seethed with excitement, remove the incrustation scale fragment.

In preferable embodiment, the described conducting liquid that is positioned in the heating container is a tap water.

Described power supply to two different in nature electrode application voltage can use alternating-current, also can use direct current.

The method of utilizing dielectric principle and method in the electric field breakdown electric field to remove incrustation scale of the present invention has following advantage:

1. features high scale-removing effect, the uniform incrustation scale of hard on the heating surface area (test conditions 0.2-5mm) expulsion rate is more than 90%, and the uniform incrustation scale of hard of part incrustation scale that heating surface is residual and non-heating surface (area in conducting liquid) can in use progressively come off.

2. the scale removal time lacks, and method is simple.

3. do not have acid pollution and produce, do not need a large amount of flushing with clean water, free from environmental pollution.

4. can adopt low voltage, too small in order not make electric current, can increase the contact area of conducting plates and water.

5. the electric field descalling technique is not with the incrustation scale dissolving, and just the bonding surface with incrustation scale and metal punctures little power consumption.

Now the invention will be further described in conjunction with the accompanying drawings:

Fig. 1 shows the DC electric field apparatus for eliminating sludge.

Fig. 2 shows the alternating-electric field apparatus for eliminating sludge.

Fig. 3 shows the structure of metal vessel and incrustation scale key coat.

Electric field incrustation scale clearance technique of the present invention mainly adopts electric field breakdown electric field medium Principle. More specifically be to utilize the electric field that forms between conducting liquid and the canister to hit Wear dielectric principle in the water. With running water as the conduction in the metal fouling container Liquid. Add certain voltage between water and canister, metal is good conductor, voltage Fall and can disregard, mainly on water and scale crust, dry incrustation scale is non-conductive in voltage drop, Incrustation scale in the water has certain electric conductivity, and its resistivity is bigger than water, in series circuit, Electric current equates that voltage drop equals U=IR, and the resistance that is exactly which position is more big, the resistance two ends Potential difference just more big. Incrustation scale descends as the anti-electric field breakdown ability of dielectric in water.

The generation of incrustation scale is long process, adds the factor such as be heated, the closer to metal, The hardness of incrustation scale is more high, and quality is more close, and water penetration is more little, and electric conductivity is more poor, especially With the faying face of metal on, the oxide-film of incrustation scale and metal forms one deck film close than matter See Fig. 3, Fig. 3 shows local one jiao of canister, is attached with at the inwall of canister wall 1 Scale crust 2, the binder course of scale crust and metallic walls are the film 21 that is of close texture, and incrustation scale is close The part 22 of inner chamber is loose for quality, the structure of porous eye, and the resistance of described rete 21 is bigger, The voltage drop that produces is also big, when voltage drop reaches certain value, and under the effect of hydrone, electricity The field will puncture this tunic, this tunic dissolving, and with electrochemical reaction. Incrustation scale and metal Faying face separates. If (oxide-film of metal is non-conductive, and electric field is also with its puncture) keeps Voltage is constant, and electric field will further puncture near the closeer incrustation scale of metal one side quality, by In the effect that punctures, the electric current in the circuit increases gradually. Remove voltage, bleed off in the container As the water of conducting liquid, add new running water, ebuillition of heated 3-5 minute, boiling could The incrustation scale binder course is expanded, further accelerate the incrustation scale Automatic-falling.

In the electric field descaling method, use the AC and DC power supply all can. Two kinds of electric currents are removed water Dirt respectively has characteristics.

1. the DC electric field water scale removing device is seen Fig. 1, has incrustation scale in heated metal container 1 Layer 2 is soaked in conducting liquid for example in the running water with scale crust, hangs in conducting liquid One conductive plate 4, this conductive plate 4 and canister wall 1 are connected to rectifier filter 5 A positive and negative utmost point, this rectifier filter 5 is connected with pressure regulator 6, and this pressure regulator connects the 220V power supply. At first add a certain amount of water in hot water tank, the height of water should be lower than incrustation scale and form appearance Long-pending height to prevent metal and water large tracts of land conduction, causes electric leakage, and is unfavorable to scale removal. 1. galvanic negative pole is connected on the metal of fouling, and positive pole is put into water, not with incrustation scale and Metal Contact. Have electric current to flow through in (50-300V) ammeter after the energising, at incrustation scale thinner or The defective place of incrustation scale has a large amount of bubbles to produce below incrustation scale. In other condition In the constant situation, voltage is more high, and electric current is just more big, and the bubble of generation is just more many. Warp Cross the faying face overwhelming majority of incrustation scale and metal after switching on 1-2 hour and separate some one The incrustation scale of position cracks under the effect of internal stress. Remove voltage, more renew water, To the water ebuillition of heated. Owing to produced the gap between incrustation scale and the metal, be full of in this gap Water, this part water since quantity few, heating surface area is big, produces violent boiling, Under the effect of this part water boiling power, incrustation scale will expand fragmentation, and from metal Come off. Negative pole with dc source connects canister, and the current potential on the canister is zero, Use safety. If 2. the positive pole with dc source is connected on the canister of fouling, with negative Utmost point water receiving, scale removal speed is fast with 1. comparing, because. It is accompanied by sun after electric field breakdown Utmost point oxidized metal container. Metal shell connects the positive pole of dc source, and outer casing electrification has necessarily Danger.

2. the AC field water scale removing device is seen Fig. 2, and this device is basic identical with Fig. 1, the experiment bar Part is constant, and dc source is changed into AC power, voltage 50-220V, the gold of a utmost point and fouling Belong to container and link to each other, a utmost point and water connect, and descale effect is similar to direct current. Method, equipment Simpler, shortcoming is uncontrollable polarity, and metal shell is charged, and certain danger is arranged.

The embodiment of the invention one, the aluminum metal water receptacle, the cylindrical diameter 200mm of volume, the incrustation scale thickness of heating surface is 5mm, add the 100V voltage of alternating current, electric current 0.5-0.7A after 1.5 hours, removes voltage and changes clear water into, be placed on fire and go up heating, seethe with excitement after 3-5 minute, the hard incrustation scale integral body of heating surface comes off, and conducting liquid and the two poles of the earth do not have obvious aluminum compound and generate.

Embodiment two, cylindrical aluminium water receptacle, diameter 200mm, heating surface incrustation scale thickness 3mm adds the 100V volts DS, with anodal water receiving, connects container with negative pole.1.5 after hour, change water, ebuillition of heated 3-5 minute, heating surface hard incrustation scale expulsion rate reached more than 90%, the compound that does not have tangible aluminium generates.

Embodiment three, cylindrical aluminium water receptacle, diameter 200mm, heating surface area incrustation scale thickness is 3mm, adds the 75V volts DS, connect metal vessel with positive pole, the negative pole water receiving is after 1 hour, change the water ebuillition of heated after 3-5 minute, heating surface hard incrustation scale expulsion rate reaches 90%, has the compound of aluminium to generate.

Embodiment four, cylindrical cast iron water receptacle, diameter 200mm, heating surface incrustation scale thickness 2mm adds the 120V volts DS, anodal water receiving, negative pole connects metal vessel, 1.5 after hour, change water, ebuillition of heated 3-5 minute, the hard incrustation scale expulsion rate of heating surface reaches more than 90%, and cast iron water receptacle surface still keeps the oxide film of black.

Claims

1. method of utilizing electric field between conducting liquid and the metal vessel to remove incrustation scale, it is characterized in that: its principle of work and step comprise

2. electric field as claimed in claim 1 is removed the method for incrustation scale, and it is characterized in that: the concrete steps of described method are:

3. electric field as claimed in claim 1 is removed the method for incrustation scale, and it is characterized in that: in preferable embodiment, the described conducting liquid that is positioned in the heating container is a tap water.

4. electric field as claimed in claim 1 is removed the method for incrustation scale, and it is characterized in that: described power supply to two different in nature electrode application voltage can use alternating-current, also can use direct current.