CN1479094A

CN1479094A - Method and device for eliminating carbon dioxide influence in hydrogen electric conductivity measurement

Info

Publication number: CN1479094A
Application number: CNA021366713A
Authority: CN
Inventors: 闻人勤; 丁桓如
Original assignee: Shanghai University of Electric Power
Current assignee: Shanghai University of Electric Power
Priority date: 2002-08-27
Filing date: 2002-08-27
Publication date: 2004-03-03

Abstract

A method and equipment for eliminating the affection CO2 in measuring the electric conductivity of hydrogen in purified water used for power plant features that the second one of two exchange columns can perform exchange with ions other than CO2 ions. As a result, the ion states in the water discharged by two exchange columns and in turn their electric conductivities are different. The difference is compared with the basic parameter to obtain the content of CO2 in water.

Description

Eliminate CO 2Method and device during the hydrogen conductivity of influence is measured

Technical field

CO in the water when the present invention relates to a kind of hydrogen conductivity of eliminating pure water in firepower and the atomic force generating plant and measuring ₂The method and the device of influence.

Background technology

At present, conductivity is an industrial conventional means to dirt content test in the water.In the steam quality standard of the condensate water of firepower and atomic force generating plant, feedwater, make-up water, hydrogen conductivity is an important parameter.So-called hydrogen conductivity is that water is passed through to survey its conductivity behind the Hydrogen cation exchange column, and purpose is that kation in the water is all become H ⁺, eliminate and regulate water PH and the influence of the artificial ammonia that adds.It is the index of generating plant steam purity that the hydrogen electricity is led, and also is the important indicator of judging whether condenser of power plant leaks.The CO that in the mensuration of hydrogen conductivity, dissolves ₂Influence to conductivity is very big, often with water in main impurity negative ion SO ₄ ^2-, Cl ^-Obscure together, cause on-the-spot erroneous judgement disconnected.So think whether can eliminate CO ₂Influence is directly connected to the accuracy that hydrogen conductivity is measured, and also is related to the safe operation of generating plant.At present, eliminate CO ₂The hydrogen conductivity measuring method of influence has two kinds: the one, boiling process, the 2nd, selective permeation embrane method.Also divide two classes in the middle of the boiling process: first ebuillition of heated, be about to detected water sample and be heated to the boiling point boiling, remove the CO of dissolving ₂After again cooling survey its conductivity; The 2nd, vacuum boiling is removed CO with the water sample boiling of reducing pressure in confined conditions ₂The boiling process disadvantage is that the application apparatus of this method is very complicated, and at the actual CO that removes ₂The time, also other volatile acid in the water sample partly or entirely may be removed, very easily bring negative error to measured value.The selective permeation embrane method is the method that adopts hollow-fibre membrane and vacuum outgas to combine, and uses this method, the equipment price costliness.

Summary of the invention

The objective of the invention is in order to overcome the shortcoming of prior art, provide that a kind of device therefor is simple, cost is low and can eliminate CO in the dehydrogenation conductance measurement ₂The method and the device of influence.

The method applied in the present invention step is as follows:

1, behind the hydrogen type strong acid cation exchange column, connect the acid-exchange resin that pretends to be fragile in again, resin is the exchange column of metallic ion type;

2, at the no CO of water inlet ₂With CO is arranged ₂, and to measure two posts respectively under the situation such as impurity variable concentrations in the water and go out electrical conductivity of water, Input Data Process tries to achieve into that water does not have CO ₂With CO is arranged ₂, and the relation of impurity concentration and two exchange column water outlet conductivity differences in the water;

3, in data processor, contrast, obtain CO in the water with the various basic parameters of depositing in advance ₂Content reaches the modified value to hydrogen conductivity, CO in the water that is eliminated ₂Hydrogen conductivity value after the influence.

For realizing that the required device of above-mentioned side is: behind the Hydrogen cation exchange column, be connected to an ion exchange column RM again, the conductivity table that is provided with behind each exchange column is connected with data processor, and this data processor is eliminated CO with demonstration ₂The conductivity table of hydrogen conductivity connect.

The present invention is to be a special exchange column by means of second exchange column, it can with CO in the water ₂Outside ion exchange, ought contain CO like this ₂Water by behind two exchange columns, two exchange column water outlet intermediate ion state differences, difference also appears in conductivity, with this difference and the basic parameter contrast of trying to achieve through overtesting, thereby learns CO in the water ₂Such principle of content.Therefore its equipment is simple, and expense is few, and is easy to operate simple, is the method and apparatus that has Practical significance and can apply.

Description of drawings

Fig. 1 is a systematic schematic diagram of the present invention.

Embodiment

This embodiment is illustrated in conjunction with the accompanying drawings, first exchange column is the hydrogen type strong acid cation exchange resin column that original hydrogen conductivity is measured usefulness, acid cation exchange resin pretends to be fragile in second exchange column, the exchange column body structure is identical with the original hydrogen type resin-column, is regenerated as metallic ion type (RM).Used resin has a characteristic among the ion exchange column RM, and it only and strong acid anion (SO ₄ ^2-, CL ^-) strong acid (H by generating behind the Hydrogen cation exchange column ₂SO ₄, HCI) reaction, the kation of strong acid anion correspondence is by H in the water outlet ⁺Be exchanged for M.And to weak acid anion (CO ₂) by not reaction of weak acid corresponding behind the RM exchange column, water outlet still is CO ₂(H ₂CO ₃).Thus, with strong acid anion (SO ₄ ^2-, CL ^-) and CO ₂Make a distinction.

First exchange column goes out consisting of of water conductivity (K+H): H ₂SO ₄, HCI, CO ₂(H ₂CO ₃)

Second exchange column goes out consisting of of water conductivity (K+M): MSO ₄, MCI, CO ₂(H ₂CO ₃)

The value and the CO of conductivity of (K+H) conductivity-(K+M) then ₂Irrelevant, only and SO ₄ ^2-, CL ^-Relevant.Strong acid anion (SO in the tested water ₄ ^2-, CL ^-) volumetric molar concentration

The molar conductance of molar conductance-M of H is for being a constant A under the specific service condition.A value in this device is to try to achieve by test, and the factor that influences the A value has temperature, flow velocity, RM resin situation etc.Test procedure of the present invention is:

1, two exchange columns are packed into the resin of desired form

2, wash

3, press the basic parameter of trial value adjusting gear

4, measure.

Like this, by test, trying to achieve into, water does not have CO ₂With CO is arranged ₂Under the situation, the relation of impurity concentration and two exchange column water outlet conductivity differences in the water in database Input Data Process such as these differences, with various basic parameter contrasts of depositing, obtains CO in the water again ₂Content reaches the modified value to hydrogen conductivity, thereby CO in the water is eliminated in indication ₂After the hydrogen conductivity value.

Claims

1, a kind of elimination CO ₂The hydrogen conductivity measuring method of influence is characterized in that method step is as follows:

(1) behind the Hydrogen cation exchange column, connect the acid-exchange resin that pretends to be fragile in again, resin is the exchange column RM of metallic ion type;

(2) at the no CO of water inlet ₂With CO is arranged ₂, and to measure two posts respectively under the situation such as impurity variable concentrations in the water and go out electrical conductivity of water, Input Data Process tries to achieve into that water does not have CO ₂With CO is arranged ₂, and the relation of impurity concentration and two exchange column water outlet conductivity differences in the water;

(3) in data processor, contrast, obtain CO in the water with the various basic parameters of depositing in advance ₂Content reaches the modified value to hydrogen conductivity, CO in the water that is eliminated ₂Hydrogen conductivity value after the influence.

2, CO is eliminated in a kind of realization ₂The device of the hydrogen conductivity measuring method of influence, it is characterized in that, behind Hydrogen cation exchange column (1), be connected to an ion exchange column RM (2) again, each exchange column is connected with data processor (4) by conductivity table (3) separately, and this data processor is eliminated CO with demonstration ₂The conductivity table (5) of hydrogen conductivity connect.