JPS5919721B2 - Method for concentrating adhesive substances - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for concentrating a substance having adhesive properties, and more particularly to a concentration method that prevents the formation of deposits and enables continuous operation for a long time.

In recent years, with the decrease in the supply of petroleum resources, attention has been paid to the reuse of various industrial wastes, waste oil, waste water, etc., which have been disposed of by methods such as disposal and incineration.

These substances often contain active ingredients that can be used as solvents, resin raw materials, fuel oil, etc.

As a method for recovering the active ingredients in these substances, the method of evaporation and concentration is convenient and relatively easy to operate, and is therefore highly practical.

However, these substances are generally mixtures of various components, and during the process of concentration, solids are formed or become very viscous substances, which can cause adhesion and reduce the recovery rate of active ingredients. The more you try to increase the value, the more the above phenomenon becomes more noticeable.

Batch-type evaporators are mainly used in conventional methods for recovering active ingredients, but due to the above-mentioned phenomena, the heat transfer efficiency decreases and the processing time is long.

It has drawbacks such as requiring a great deal of labor and time for post-processing such as cleaning after completion of concentration.

The present invention (''!) aims to eliminate the above-mentioned drawbacks and provide a method for concentrating adhesive substances that can be operated continuously for a long time while maintaining high heat transfer efficiency. be.

The main point of the invention is to perform evaporative concentration using a thin film evaporator with a dedicated cleaning liquid inlet as a concentrator, and to control the type of cleaning liquid, injection amount, etc. according to the type of raw material to be treated or the properties of the concentrate. It is characterized by:

Embodiments of the present invention will be described below with reference to the drawings.

In FIGS. 1 to 7, common parts are denoted by the same reference numerals.

FIG. 1 shows an example of a vertical thin film evaporator used in the present invention, and the structure and operation of the thin film evaporator 11 will be explained with reference to FIG.

40 is a cylindrical heat transfer shell, inside which rotor blades 2 are arranged radially.
A rotating shaft 1 is provided, and this rotating shaft 1 is supported by an upper bearing 42 and a lower bearing 4 so that the gap 41 between the heat transfer shell 40 and the rotor blade 2 is maintained at an appropriate value, and is supported by a drive pulley. 43 so that it can be rotated by a motor (not shown).

A jacket 3 having a heating medium inlet 8 and a heating medium outlet 9 is provided outside the heat transfer 40, and is heated by the heating medium.

In addition, the heat transfer 40 has a cleaning liquid 44 located at an arbitrary position in the lower half thereof.

A plurality of the cleaning liquid portions 44 may be provided in the longitudinal direction of the shaft or in the circumferential direction.

The raw material to be concentrated is injected into the thin film evaporator 11 from the raw material supply port 5, forms a thin film on the inner wall surface of the heat transfer 40 by the action of the rotating rotor 2, and moves downward through the gap 41. .

Since the heat transfer member 40 is heated by the heat medium in the jacket 3, the evaporative components in the raw material evaporate.

The concentrate that has completed evaporation is extracted through the concentrate outlet 6.

On the other hand, the evaporated gas moves upward through the heat transfer space 40 and is extracted from the evaporated gas outlet lower part.

Further, the cleaning liquid is continuously or intermittently injected into the lower half of the heat transfer 40 from the cleaning liquid 44 to clean the deposits generated on the heat transfer 40 and the rotor 2 .

A part of the cleaning liquid is evaporated by the above-mentioned evaporation effect and combined with the evaporated gas, and the rest is combined with the concentrate and extracted.

The above-mentioned action allows the adhesive substance to be concentrated.

Generally, when various industrial wastes, waste oil, waste water, etc. are heated for a long time, some or all of their components decompose and deteriorate, and truly effective components may not be recovered.

However, since the thin film evaporator 11 forms a thin film and heats it as described above, it can complete evaporation in a very short time and can efficiently concentrate the substance with a short residence time. It is ideal as a machine.

Particularly when concentrating a substance that has adhesive properties such as the above-mentioned substance, it is truly effective to use the thin film evaporator 11 provided with the cleaning liquid 44.

The thin film evaporator 11 has a vertical type and a horizontal type, which type can be used depending on the properties of the raw material to be treated.

That is, when the viscosity of the concentrate is relatively low, a horizontal type is appropriate, and when the viscosity is high, a vertical type is more appropriate.

An embodiment of the present invention will be described with reference to FIG.

The raw material 21 is injected into the thin film evaporator 11, where the components to be evaporated are evaporated and concentrated and guided to the concentrate receiving tank 12, where the concentrate 2
Extract as 6.

The evaporated gas 23 is guided to the cooler 15 where it is cooled by a refrigerant 34, where it is cooled and condensed to form a condensate 22, which enters a condensate receiving tank 16 and is extracted.

The cleaning liquid 31 is injected into areas of the thin film evaporator 11 with heavy adhesion to clean the required areas, part of which is combined with the evaporated gas, and the remaining part is combined with the concentrate.

Due to this cleaning action, the thin film evaporator 11 is always maintained in a clean state free from adhesion.

With the above-described configuration and operation, it is possible to concentrate adhesive substances in a continuous operation in a short time, efficiently, at low cost, and without having to stop the operation of the apparatus for cleaning.

Example A vertical thin film evaporator 11 having a heat transfer device 40 with a diameter of 100 mm and a length of 1000 mm and a cleaning liquid evaporator 44 placed 700 mm from the top was equipped with saturated steam at 160° C. as a heat medium and a 10% solid vapor. As a result of concentrating the sludge containing substances to a concentration of 70% (1) When the cleaning liquid (tap water) is used as the amount of raw material injected, 8
The amount of evaporation does not change at all after continuous operation for hours.

The raw material injection rate at this time was 607/h.

(2) When no cleaning liquid was injected, the amount of evaporation decreased to ÷ the initial amount 4 hours after the start of operation.

At this time, the formation of deposits was observed on the bottom + portion of the heat transfer 400.

When the same concentration operation was performed in an evaporator with an internal volume of 1001,
The amount of evaporation per unit time is + of the thin film evaporator 11 in terms of heat transfer area, and the amount of evaporation decreases extremely from the point when the concentration exceeds 50%, and it takes until a concentrate with a concentration of 70% is obtained. The time required was three times that of the case (1) above, and strong deposits were formed, requiring a large amount of time for cleaning.

FIG. 3 shows another embodiment of the present invention, in which a part of the raw material 21 is used as the cleaning liquid 31 injected into the thin film evaporator 11, and the injection amount is It is controlled by a control valve 51 and a cleaning liquid control valve 52, and the rest is the same as in the case of FIG.

With this configuration, a part of the raw material can be used as a cleaning liquid as is, so special equipment such as a cleaning liquid tank is not required, and the concentrate and condensate components do not contain impurities other than the raw materials. There is.

FIG. 4 shows still another embodiment of the present invention, in which the cleaning liquid 31 to be injected into the thin film evaporator 11 is
A portion of the condensate 22 is used, and the amount of injection is controlled by a condensate control valve 53 and a cleaning liquid control valve 52, and the rest is the same as in the case of FIG.

With this configuration, a part of the M material 22 can be used as a cleaning liquid as it is, so in addition to having the same effect as the embodiment shown in FIG. 3, condensate generally has the property of dissolving deposits. Since it is strong, it has the effect of requiring less injection of the cleaning liquid 31.

FIG. 5 shows still another embodiment of the present invention, in which the driving power of the rotor blades 2 of the thin film evaporator 110 is detected by a power detector 55, and the cleaning fluid is The control valve 52 is opened and closed to control the amount of cleaning liquid 31 injected, and the rest is the same as the case shown in FIG. 2.

In this case, it has been found from experimental results that when deposits begin to form, abnormalities such as increased power due to increased viscosity or increased power fluctuations occur, and certain measures are taken to prevent these abnormalities from occurring. It is sufficient to control the power value.

By configuring in this way, it is possible to save the injection amount of the cleaning liquid 31, which not only reduces costs, but also has the effect that a concentrate of constant quality can always be stably obtained.

FIG. 6 shows still another embodiment of the present invention, in which the concentrate 26 immediately after being extracted from the thin film evaporator 11 is shown in FIG.
The temperature of the liquid is detected by a concentrate thermometer 56, and the injection amount of the cleaning liquid 31 is controlled by opening and closing the cleaning liquid control valve 52 so that this temperature becomes constant. Same as in case.

In this case, experimental results have shown that there is a certain relationship between the temperature and concentration of the concentrate 26, and it has also been found that deposits are more likely to form as the concentration increases.
It is sufficient to control the temperature to the maximum limit that does not cause adhesion.

This configuration provides the same effect as the embodiment shown in FIG. 5.

FIG. 7 shows still another embodiment of the present invention, in which the evaporated gas 2 immediately after being extracted from the thin film evaporator 11 is
3 is detected by an evaporative gas thermometer 57, and the cleaning liquid control valve 52 is opened and closed to control the injection amount of cleaning liquid 31 so that this temperature is kept constant. Same as in case.

In particular, when there are two or more evaporated components, each with a different boiling point, it has been found that there is a certain relationship between the temperature of the evaporated gas 23 and the concentration of the condensate 26, as shown in Figure 6. Control may be performed in the same manner as in the embodiment shown.

This configuration provides the same effect as the embodiment shown in FIG. 5.

Since the present invention is as described above, it has the following effects.

(1) Active ingredients can be efficiently and continuously recovered from adhesive substances, and various expenses such as operating costs and personnel costs can be reduced.

(2) The device is easy to start and stop, can process various substances as needed, and is economical.

(3) Since there is no need to frequently clean the device, there is less need to enter and exit the hazardous environment associated with cleaning work, resulting in high safety.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an example of a vertical thin film evaporator used in the present invention, FIG. 2 is a system diagram showing an embodiment of the present invention, and FIGS. It is a system diagram showing an example. 1...rotating shaft, 2...rotor blade, total...
...Jacket, 4...Lower bearing, 5...
... Raw material supply port, 6.-- Concentrate outlet, 7.-
...Evaporation gas outlet, 8...Heat medium inlet, 9.
... Heat medium outlet, 11 ... Thin film evaporator, 1
2...Concentrate receiving tank, 15...Cooler,
16... Condensate receiving tank, 21... Raw material,
22... Condensate, 23... Evaporated gas,
26...Concentrate, 31...Washing liquid, 3
2... Heat medium, 34... Refrigerant, 40...
... Heat transfer cylinder, 41 ... Gap, 42 ...
... Upper bearing, 43 ... Drive pulley, 44.
...Cleaning liquid inlet, 51...Raw material control valve,
52...Cleaning liquid control valve, 53...Condensate control valve, 55...Power detector, 56-...
...Concentrate thermometer, 57...Evaporating gas thermometer.

Claims (1)

[Scope of Claims] 1. A raw material containing an adhesive substance is supplied to a thin film evaporator having a heating jacket to remove the evaporated component, and a cleaning liquid is supplied to the thin film evaporator to clean the adhered product. In a method for concentrating a substance having an adhesive property,
A method for concentrating a substance having adhesive properties, characterized in that the supply amount of the cleaning liquid is controlled according to the driving power of the thin film evaporator. 2. The method for concentrating a substance having adhesive properties according to claim 1, wherein a part of the raw material is supplied as the cleaning liquid. 3. The method for concentrating a substance having adhesive properties according to claim 1, wherein a part of the condensate obtained by cooling and condensing the evaporated components is supplied as the cleaning liquid.