JPH08327788A - Waste liquid evaporation device - Google Patents

Abstract

PURPOSE: To provide a waste liquid evaporation device for reactor power plant and the like which has a function of eliminating bubbles in waste liquid at every low cost without using defoaming agent and other chemical liquid. CONSTITUTION: Provided is a waste liquid-evaporation device for processing washing drain containing surfactant generated in a reactor power plant and the like as waste liquid containing in a tank-shape vessel. The device is provided with a spray 4 placed in the upper part in the vessel capable of spraying waste liquid 01, etc., toward the liquid surface, and heaters 5, 6 around the vessel along the inner circumference at higher place than the liquid surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste liquid evaporation device used in a nuclear power plant or the like, and more particularly to a waste liquid evaporation device provided with means for defoaming a foam layer generated in the same device.

[0002]

2. Description of the Related Art In a waste liquid evaporator in a nuclear power plant, foaming may occur during the evaporation treatment depending on the components of the waste liquid, which is an obstacle to the evaporation. Was there.

FIG. 2 is a diagram of a conventional device used for defoaming the waste liquid. Waste liquid flows into the evaporator 2 in the direction of the arrow, is heated by the heater 3, and the vapor thereof flows in the direction of the arrow. Since there is a high possibility that the waste liquid containing the surfactant foams when heated and evaporated, the foaming is suppressed by injecting the defoaming agent from the defoaming agent injection device 1 before flowing into the evaporator 2.

[0004]

The conventional defoaming means using the above defoaming agent has the following problems (1) and (2) to be solved. (1) The antifoaming agent is not effective for all foaming substances, and the foaming property and stability are different depending on the substance, so that it is necessary to select an antifoaming agent according to its characteristics. In the case of conventional radioactive waste liquid treatment, there is a problem that it takes a lot of time and labor to investigate the properties of the waste liquid and to select an antifoaming agent in order to make the defoaming effect effective. (2) In order to inject the defoaming agent into the waste liquid line, a device for that purpose is required (tank, pump, etc.) and there is a problem that the equipment scale increases.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a waste liquid evaporation device which solves the above problems and can defoam regardless of the properties of the processing liquid by merely performing mechanical and physical foam breaking.

[0006]

Means for Solving the Problems As a means for solving the above problems, the present invention is to evaporate a waste liquid containing cleaning wastewater containing a surfactant generated in a nuclear power plant or the like into a tank-shaped container as a waste liquid and treating it by a distillation method. The apparatus is provided with a spray provided above the inside of the container so that waste liquid or the like can be sprayed toward the liquid surface, and a heating body surrounded by a position slightly higher than the liquid surface along the inner circumference of the container. It is intended to provide a waste liquid evaporation device characterized by the following.

[0007]

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

That is, since a spray is provided above the container so that waste liquid can be sprayed toward the liquid surface, the size and speed of the fog droplets to be sprayed can be adjusted appropriately to break and eliminate bubbles on the liquid surface. You can

Next, since a heating element is provided along the inner circumference of the container at a position slightly higher than the liquid surface, bubbles adhered to the periphery of the container and bubbles remaining along with the adhered bubbles are hard to be erased depending on the spray. It disappears when heated by a heating element.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG. The same components as those in the conventional example are designated by the same reference numerals, and the description thereof will be omitted unless necessary.

FIG. 1 is a diagram showing the main part of the apparatus of this embodiment.
(A) is a schematic side sectional view, (b) is a sectional view taken along the line AA of (a).

In the figure, numeral 4 is a spray provided downward in the evaporator 2 and capable of spraying waste liquid toward the liquid surface (hence facing bubbles 02), and numeral 5 is the inner circumference of the evaporator 2. A heating plate surrounded by the waste liquid 01 at a position slightly higher than the liquid level of the waste liquid 01, 6 is provided at a portion corresponding to the heating plate 5 on the outer periphery of the evaporator 2 and communicates with the heating plate 5 in a liquid-tight manner. 5 is a heater for heating 5. Other configurations are the same as the configurations in which the defoaming agent injection device is removed from the conventional example.

Next, the operation of the above configuration will be described.

First, for example, the waste liquid 01 pumped up from the evaporator 2 is sprayed toward the liquid surface from the spray 4 at a relatively high pressure. Then, the bubbles 02 on the liquid surface are broken by the high-speed droplets of the sprayed waste liquid 01 and disappear. At this time, the bubble 02 formed in the inner peripheral corner of the evaporator 2 does not easily break because the formation angle is small and stable when the foam film is viewed in cross section due to the liquid surface and the inner peripheral surface. It is conceivable that the heating plate 5 is heated by the heater 6 and bubbles 0
2 is heated to weaken the intermolecular bonding force by increasing the molecular motion of the foam film molecule, and to cause the lack of the foam film molecule due to accelerated heating of evaporation (evaporation of molecules), forcibly defoaming.

As a result, the bubble 02 on the liquid surface disappears and the waste liquid 01
The normal vaporization of is achieved.

The heating means of the heating plate 5 may be freely selected, for example, a system using an electric heater installed inside the heating device 6 may be used, and the heating plate 5 is made of a magnetic material and is provided in the heating device 6. A so-called microwave oven system may be provided with an alternating voltage device. Intermolecular vibration friction heat by high frequency, secondary electromagnetic induction resistance heat, heating plate 5 is hollow, and high temperature heating gas, heating steam, etc. are supplied from the outside. Alternatively, the heating liquid may be passed through (the heating device 6 is not particularly required in this case).

Further, the heating plate 5 is also configured such that the inner periphery of the evaporator 2 is continuously surrounded. However, although the heating plate 5 has an overall surrounding structure for defoaming, it is fine, for example, locally in the circumferential direction. Easy to install, remove and maintain,
The members that individually perform the heating function are continuously attached,
You may be surrounded as a result.

As described above, according to the present embodiment, first, the bubbles 02 are extinguished by utilizing the kinetic energy by the spray 4, and then (of course, they may be used together at the same time), and then the remaining evaporator 2 is eliminated.
Since the bubbles 02 in the inner corner are forcibly erased by the heating plate 5, the liquid level of the waste liquid 01 is always kept in good conditions for evaporation, and there is an advantage that an efficient evaporation process can be performed.

Further, there is an advantage that the high efficiency equipment as described above can be obtained extremely easily and at low cost.

Further, since the spray liquid from the spray 4 may be, for example, the waste liquid 01, and no extraneous injection agent or the like is used, no change occurs in the processing liquid, and therefore, special post-treatment, neutralization treatment or the like is required. There is an advantage that it does not.

Further, since the bubbles are defoamed by the kinetic energy and the heat energy, there is an advantage that there is no need to investigate the liquid quality in advance and select an appropriate defoaming agent as in the conventional case.

[0022]

Since the present invention is constructed as described above, it has the following effects (1) to (4). (1) It is possible to surely defoam. (2) Compared with the case of using a defoaming agent, defoaming can be performed without being affected by the properties of the waste liquid. That is, it is possible to easily defoam. (3) The scale of the defoaming equipment can be reduced as compared with the case where the defoaming agent is used. That is, a tank and a pump are not required unlike the conventional case. Therefore, it can be obtained at low cost. (4) Since no treatment agent is used, no extra preliminary component investigation or post-treatment is required.

[Brief description of drawings]

FIG. 1 is a diagram of a main part of a waste liquid evaporator according to an embodiment of the present invention, in which (a) is a schematic side sectional view and (b) is A- in (a).
A sectional view taken along arrow A,

FIG. 2 is a side sectional view of a conventional waste liquid evaporator.

[Explanation of symbols]

 2 Evaporator 3 Heater 4 Spray 5 Heating plate 6 Heater 01 Waste liquid 02 Foam

Claims (1)

[Claims] 1. In a waste liquid evaporation device in which cleaning waste water containing a surfactant generated in a nuclear power plant or the like is put into a tank-shaped container as a waste liquid and treated by a distillation method, the waste liquid or the like can be sprayed toward the liquid surface. A waste liquid evaporator comprising: a spray provided above the inside of the container; and a heating body surrounded by an inner periphery of the container at a position slightly higher than the liquid surface.