JPH05215678A - Measuring method of object forming accu- mulated matter in non-transparent liquid - Google Patents

Abstract

PURPOSE: To enable spontaneous answer analysis using reflectivity by a method wherein a disk is dipped in an opaque liquid so that a film formation is deposited, lights are emitted, and reflectivities of this sample and a pure object are compared. CONSTITUTION: A disk 10 having a rotation axis 11 comprises a hydrophilic metal surface A1 and a hydrophobic film B1. Sections A1, B1 are dipped partially in an opaque liquid having a liquid level 12, the disk 10 is rotated in 180 deg. after a specific period so that both sections are exposed. A target 1 in the section A1 is directed towards a light source 16 and beams of strength i are emitted. A sensor 18 responses reflected lights and strength i' is converted into a corresponding voltage V'. Next, a hole 14 of the disk 10 is directed towards the light source 16, beams of the strength i are radiated to a pure original surface 22 through the hole 14, reflected lights are incident on the sensor 18 as the referring strength i and converted into a corresponding voltage V. The thickness of a film formation of the target 1 can be decided by a difference V-V' or a ratio V'/V by a computer. All the targets 1 to 4 in the sections A1, B1 are sequentially measured.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to the measurement of unwanted deposit formation in opaque liquid streams used in industrial or manufacturing processes. The measurements are done in-situ or by immediate response analysis rather than taking liquid samples and analyzing them in some external laboratory.

[0002]

BACKGROUND OF THE INVENTION Industrial liquid streams confined in manufacturing conduits are entrained by biological or organic impurities in the equipment used to process the liquid and its efficiency. There are many examples of lowering.

A good example is papermaking equipment, where the restraint conduit is the papermaking machine itself. A colony of bacteria,
Protozoa and other simple life forms are entrained in the pulp.
They supply and propagate in native materials such as proteins, oils, carbohydrates and polysaccharides. This colony spreads into a sticky, sticky biofilm that traps other particles and deposits on the chest and other equipment in the pulp restraint conduit downstream of the chest. Not only that, this undesired film loosens due to turbulence and becomes part of the paper, leading to poor quality. Pitch (hydrophobic contaminants) present as part of wood fibers is another source of unwanted organic deposits.

As another example, the same phenomenon is found in cutting oil. The purity and efficiency of this oil is reduced, the surfactants holding the cutting oil in emulsion are adversely affected and a film is deposited on the workpiece being machined.

Our US patent application no.
In (filing date:), we are dealing with film formers in transparent process streams such as cooling tower water and performing dual beam transmission comparisons (control and sample) to detect film deposition. .. In the present invention, we address the same problem in opaque flow, where light transmission is difficult, if not impossible, to measure accurately. Instead, we use light reflectance. This will be explained below.

[0006]

Reflected light is used to measure the film formed in a liquid confined to a conduit used to treat an opaque liquid stream for the manufacturing industry. Since this flow is opaque, one cannot rely on the light transmission value. In the present invention, a film-depositing surface (disk, coupon) is immersed in a stream, a film is deposited on this surface, the sticky film is exposed to remove and the reflected light of the film on the exposed surface is measured. To do. The intensity of this reflected light reflects the film thickness. If the thickness exceeds a predetermined tolerance limit, the microprocessor activates a pump to feed the stream with a treating agent which disperses or destroys the film former.

More particularly, the present invention may be a homogeneous material, but is preferably characterized by the use of a disc or discrete shape containing discrete compartments providing the surfaces of different materials. There is. The disc is partially immersed in an opaque process stream and is supported for rotation. Rotation of the stepper motor causes the disc to rotate around at selected intervals, exposing the previously immersed compartment for measurement by the optical sensor. This sensor measures the intensity of light (emitted from a light source) reflected (reflectance) from one or more target areas containing a film sample.

The thicker the film, the less light is reflected from the spot or target. The exposed surface may be indexed with a stepper motor so that the reflectance readings of the accumulated deposit are averaged over multiple spots on the disc.

By maintaining the soak for a relatively long period of time, the soaked compartment simulates exposure of the device (process conduit and associated parts) to long-term or passive buildup of deposits. It may then be a long-term average reflectance, or a single reflectance reading corresponding to long-term immersion, but after taking these readings the disc is immediately rotated to create a fresh compartment. , Turbulent or simply film wetting conditions can be measured as a short term wetting surface.

The difference between this passive and film wetting condition can be significant. This passive film can be regarded as a film when bacterial preposition or growth conditions are not severe or harmful, that is, when film deposition is slow. In contrast, short dipped compartments will capture the most sticky or detrimental film formers, such as organic pitch, which is one of the more detrimental deposit formers.

To the best of our knowledge, it adheres to one part of the disc and is less harmful, ie to simulate film-forming passive film formation and to other parts of the disc it is strong or harmful. There is no technique associated with the present invention which is characterized by reading the reflectance from a disc that has been continuously long-term and short-term immersed in an opaque liquid, including one that simulates various film-formers.

There are systems that detect internal film formation. That is, US Pat. 4,912,332 and 3,757,210. However, these disclosures do not follow the features of the present invention.

The features of the present invention are illustrated by various schematic drawings.

In FIG. 1, a disc 10 rotatably secured to a shaft 11 is preferably divided into two compartments which do not necessarily have the same area. Compartment 10A represents a ferrous metal surface (which is believed to be hydrophilic), which
Used in so-called mechanical chest (mill) paper mills to simulate equipment such as typical process equipment that tends to deposit organic film formers. Ideally, this disc would be stainless steel,
Compartment 10A is preferably stainless steel.
However, compartment 10A is exposed when the device is exposed to a process fluid that is considered opaque when light transmission is a concern.
It suffices if there really is a tendency to accumulate film formers in proportion to their exposure.

The other segment 10B represents a hydrophobic surface, preferably Teflon ™ resin.

Now, as shown in FIG. 2, if the disc is rotated 90 ° in the counterclockwise direction and partially immersed in an opaque liquid having a liquid surface 12 (for example, paper pulp in a chest of a papermaking machine), The immersion part will have a metallic or hydrophilic compartment A1 and a hydrophobic compartment B1. Both compartments will be contaminated with existing deposit formations. In particular hydrophobic compartments will deposit organics such as oil and pitch. On the other hand, metal compartment A1 will receive a source of bacterial film formers.

When the disc is rotated 180 ° counterclockwise to the position shown in FIG. 3, both compartments A1 and B1 previously immersed are
Is exposed. The broken line shows the area that was immersed. These soaked areas can be measured optically as detailed below. This measurement is for A1 that has undergone long-term immersion.
The thickness of the film in the regions B1 and B1 is quantitatively measured by the reflectance.

During the optical measurement of the previously submerged section A1 and B1 sections, sections A2 and B2 are immersed. This takes about a few minutes, after which the disc is rotated an additional 180 ° counterclockwise so that the sections A2 and B2 are exposed for optical measurement.
Turn to be Figure 4. Here again the dashed line indicates the limit of immersion.
Now compartments A2 and B2 are the most sticky film formers,
That is, it can be optically checked or analyzed for those that tend to stick most strongly to the device.

Referring now to FIGS. 5 and 6, these correspond to FIG. 3 (long-term immersion) and FIG. 4 (short-term immersion).
However, only the immersion area to be measured is shown in a simplified manner with A1 and B1 (from FIG. 3) and A2 and B2 (from FIG. 4). Also in Figures 5 and 6, the circled numbers (1, 2, 3, 4) represent the radial spots or targets to be measured and averaged. However, in some areas it may be more or less target spots.

The disk 10 has holes 14 arranged radially. This hole serves as a source of contrast reflectance as described below.

According to the measurement of veil, the light absorbed by the absorbing material is proportional to its thickness. By irradiating the film with a light having a known intensity i and measuring the intensity i '(of course, weaker) of the reflected light, this law allows the thickness of the film on the disk to be measured to be measured. .. Difference (i-
i ') or the ratio (i' / i) is a measure of the film thickness.

Referring to FIG. 7, the disk 10 after being immersed for a long period of time is rotated to a position corresponding to FIG. At this position, the target is the light source (IR or UV) 16 in the section A1 in FIG.
The beam of intensity i is emitted from this light source to the target of A1. The sensor 18 reflects the reflected light, the intensity i ′,
In response to this, this intensity can be converted into a corresponding voltage V '.

Next, although not shown, the programmer activates the stepping motor to index the disc clockwise so that the hole 14 in FIG. 8 faces the light source 16. The same beam (intensity i) is emitted through the hole 14 and reflected by a clean or original surface 22 (eg clean stainless steel) and is incident on the sensor 18 as a control intensity value i with all deviations removed. Let In fact, the control intensity i (at 14) did not cause any absorption.

The reflectivity from reflector 22 provides a current control each time it is indexed to reflect the intensity of the light source. If there is no contrast for each reading, temperature change, humidity change,
Dust and the like on the optics will cause a significant deviation or bias of the light from the light source 16.

The sensor 18 converts the reflection intensity i into a corresponding voltage V.

The two corresponding values can be compared by computer and the difference (V-V ') or the ratio (V' / V) can determine the film thickness of the target spot.

This measurement can subsequently be repeated for the targets in compartment A1 and, and likewise for all targets in compartment B1. For each series of measurements, the hole 14 is aimed at the light source in order to eliminate the deviation for all readings. By doing so, the average film thickness can be measured for compartment A1, which simulates biodeposition on the device.
Similarly, the average film thickness on the hydrophobic compartment B1 can be measured, which simulates entrainment of organics such as pitch and oil in the process stream.

Following the analysis of the long-term immersion, the stepping motor is activated to rotate the disk 10 by 180 ° to move it from the position shown in FIG. 5 to the position shown in FIG. Can be similarly monitored.

With the exception of the control surface 22, the presence of the film will always reflect less light. However, the basic comparison is the intensity of light, i ', the intensity of the reflected light compared to the contrast intensity i.

In the example of measuring paper pulp flow, the disk 1
0 is immersed in so-called water or mechanical chest 30 of FIG. 9, and shaft 11 is indexed by stepping motor 32. However, the paper pulp flow to be measured is shown in FIG.
Pipe 34 to a separate test or sampling tank 36 where turbulence is simulated by an impeller 38 driven by a motor 38.
The return line is indicated by reference numeral 40, ensuring true flow and process conditions.

(Programming) The above measuring system can be controlled by a computer. The following program will be typical.

1. Step the idol of the motor and bring the disc to the position shown in Figure 3 and hold it for 24 hours.

2. At 24 hours, the disk is stepped to the position shown in FIG. 5, and the light source 1 is directed toward the target spot A1-.
Apply energy to 6.

3. Read i'at A1-
Store i'in memory; start stepper motor, index hole 14 for aiming by light source 16 and read i reflected by surface 22.

4. The stepping motor is activated to align with the target A1- and receive the reflected light of the light beam from the light source to read i'and store i '.

5. Start the stepping motor and hole 1
4 into the path of the light beam, and clean or original surface 2
Read the intensity i of the light reflected at 2.

6. The indexing of the remaining spot film in section A and the control reflectance is repeated and the value of i'is stored in memory for each step.

7. Steps for disk partition B1 ~
Is repeated and the value of i'is stored in the storage device separately.

8. For example, after the above is finished at 24 hours and 30 minutes, the stepping motor is activated and rotated to the positions shown in FIGS. To measure the film thickness.

(Data processing) The reflectance (strength i ') reading is always corrected, ie corrected for deviations, but sometimes only one reading is sufficient for each section A1 and B1 of FIG. .. The same applies to the sections A2 and B2 in FIG. However, the average is good, so many readings for each segment would be required to obtain the average i '.

In each case, the data of significance in each case are the differences or ratios of i and i ', which can be the corresponding voltages (millivolts, mV), which represent the thickness of the film. Thus, as shown in FIG. 11, the voltages V '(sample) and V'generated by the detector 18 of FIGS.
The (control) is microtreated with PC and the absorption value is determined for each reading. I.e.

Absorption value (Abs) = logi / i ′ = logV / V ′

The absorption value is proportional to the film thickness, i / i '
, The microprocessor can be programmed to solve for any of the corresponding values with which the reflected sample light is compared to the control intensity i when reflected by the control surface 22. This equivalence of values is shown in the computer printout or display in FIG. Here, the equivalent of film thickness is indicated by the vertical coordinate value. The horizontal coordinate is time t.

From this printout or screen display, trends in film deposition can be tracked. Typically increases gradually the film thickness (arithmetically) t _1, then accelerated from t ₁ at t ₂ (exponentially), which injection correction processing agent to combat deposits Are demanding to do so. Other counterparts of film thickness are possible (vertical coordinates, Figure 11). But voltage is a much easier way.

[Brief description of drawings]

FIG. 1 is a front view of a disk divided into hydrophilic and hydrophobic compartments.

FIG. 2 is a front view showing a disk partially immersed in an opaque liquid to be measured.

FIG. 3 is a front view showing a disk partially immersed in an opaque liquid to be measured.

FIG. 4 is a front view showing a disk partially immersed in an opaque liquid to be measured.

FIG. 5 is a front view showing a disk partially immersed in an opaque liquid to be measured.

FIG. 6 is a front view showing a disk partially immersed in an opaque liquid to be measured.

FIG. 7 is a diagram showing the principle of optical reflection in the present invention.

FIG. 8 is a diagram showing the principle of optical reflection in the present invention.

FIG. 9 is a schematic side view showing a state where a disc is immersed in the present invention.

FIG. 10 is a schematic side view showing a state where a disc is immersed in the present invention.

FIG. 11: Combination of a diagram showing the measurement of film thickness and the corresponding value of film thickness versus time.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Disc 10A ... Hydrophilic compartment 10B ... Hydrophobic compartment 11 ... Shaft 12 ... Liquid surface 14 ... Hole 16 ... Light source 18 ... Photosensor 22 ... Clean surface A1 ... Hydrophilic compartment B1 which formed deposit by long-term immersion … Hydrophobic compartment where deposit is formed by long-term immersion A2… Hydrophilic compartment where deposit is formed by short-term immersion B2… Hydrophobic compartment where deposit is formed by short-term immersion

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Rodney H. Banks United States, Illinois 60563, Naperville, Whiteley Road 1597

Claims (5)

[Claims] 1. A method for measuring deposit formation in an opaque liquid comprising the following steps (a)-(e): (a) A disk compartment having a surface to which the deposit formation is adsorbed in the liquid. (B) rotating the disc after a predetermined soaking time to expose the previously dipped compartment containing the adsorbed deposits to the optical measurement; (c) to measure the thickness. Irradiate a light beam to the exposed area of the adsorption film and measure the intensity of the light reflected from it to obtain the sample reflectance; (d) Measure the intensity of the same light beam reflected from a clean surface. (E) and measuring the difference between the control reflectance and the sample reflectance as a measure of film thickness. 2. Adsorbing different kinds of deposit formers,
The method of claim 1 wherein the disc has at least two compartments that provide surfaces of different nature, each compartment being subjected to steps (c), (d) and (e). 3. The disk is a ferrous metal disk, one compartment providing a surface of ferrous metal that is hydrophilic in character, and a second compartment providing a coating that is hydrophobic in character. The method of claim 2, wherein 4. The sample reflectance and the control reflectance are converted into corresponding voltages V ′ and V, respectively, and the corresponding voltage is expressed as a log V / V ′ as the absorbance of the film corresponding to the film thickness. Or the method of 3. 5. The method of claim 4, wherein log V / V 'is plotted as a function of time.