JPH07246386A - Waste water treating device - Google Patents

Abstract

PURPOSE:To obtain a clear treated water by preventing the foaming and bumping in an evaporator in the purification of the waste water contg. a foaming agent. CONSTITUTION:An evaporator 3 provided with an inlet pipe 1 for the waste water contg. a foaming agent, heating and evaporating the waste water from the pipe 1 by a heating pipe 2 in vacuum, a gas-liq. separation membrane 4 through which the water evaporated in the evaporator 3 is passed and a condenser 6 communicated through an eliminator, etc., cooling and condensing the evaporated water by a cooling pipe 5 and recovering the condensed water as treated water are provided to the waste water treating device. Accordingly, the open end 7 of the inlet pipe 1 is positioned above the liq. surface of the evaporator 3, and a foaming detector 8, e.g. an electrode type level controller, and other level controllers are provided on the ceiling of the evaporator and connected to an alarm display part 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to waste water containing a foaming agent such as a surfactant, for example, cleaning waste water discharged from a water cleaning device after mounting a printed circuit board or the like, and oil attached to machine parts to a detergent and water. TECHNICAL FIELD The present invention relates to a wastewater treatment device for removing impurities from a cleaning device to be washed with and collecting and treating the wastewater as clear treated water.

[0002]

2. Description of the Related Art Generally, as a means for purifying waste water, it is known to heat and evaporate the waste water to cool and condense the water vapor, and such means conventionally include a foaming agent such as a surfactant. It is used for wastewater treatment. That is, the waste water is heated in a vaporizer under vacuum to evaporate the moisture, and the evaporated moisture is cooled in the condensing can to form condensed water, and then the liquid in which the impurities are discharged and concentrated in the can is concentrated. In a device that discharges as concentrated water, foaming occurs when evaporating, and the evaporating can becomes full of bubbles, and the bubbles overflow from the evaporating can and enter the condensing can. Therefore, in order to prevent foaming in the evaporator, a necessary amount of antifoaming agent is injected into the inflowing wastewater for treatment.

[0003]

However, it is not possible to reliably suppress the generation of bubbles only by injecting the defoaming agent into the drainage.
The quality of treated water tends to deteriorate. Especially, since the wastewater is in contact with the atmosphere, the air is dissolved, and when this dissolved air enters the evaporator, it separates from the wastewater under vacuum to form bubbles, and the tip of the wastewater inflow pipe is the liquid in the evaporator. When you are below
The separated gas rapidly expands to several tens of times the volume under vacuum,
As a result of the phenomenon that air bubbles form bumping and the liquid in the can is blown up to the top of the can frequently, part of the liquid in the can is scattered to the condensing part, and raw water enters the treated water, resulting in purified treated water. It was a problem because there was a problem that caused deterioration of water quality. The present invention is
In order to eliminate these conventional drawbacks, it is necessary to prevent bubbling and bumping in the evaporating can into which cleaning-containing wastewater flows, and to obtain clean evaporatively treated water without contamination of the treated water. It is an object of the present invention to provide an apparatus capable of performing the above in a simple configuration and at a low cost.

[0004]

DISCLOSURE OF THE INVENTION The present invention is provided with a drainage inflow pipe into which wastewater containing a foaming agent flows, and the drainage from the drainage inflow pipe is heated by a heating pipe under vacuum to evaporate water. A wastewater treatment device equipped with a can and a condensing can which is communicated with a vapor-liquid separating member so that the water evaporated in the evaporating can flows in, and cools and condenses the evaporating water by a cooling pipe to collect it as treated water. In the above, the open end of the drainage inflow pipe is arranged above the liquid surface of the evaporator, and a foaming detector is provided on the ceiling of the evaporator to communicate with the alarm display.

[0005]

[Function] A defoaming agent is mixed with wastewater containing a foaming agent such as a surfactant and introduced into an evaporator through a wastewater inflow pipe, and is heated in a vacuum in the evaporator to evaporate water, and then the evaporation is performed. The condensed water is cooled in a condensing can to be condensed water, the condensed water is discharged as treated water, and the liquid in which the impurities remaining in the can are concentrated is discharged as condensed water. Above the liquid level inside, the rapidly expanding gas in the drainage flowing in from the drainage inflow pipe separates from the drainage and escapes into the gas phase before colliding with the liquid level, and the drainage is the liquid in the evaporator. Since most of the gas escapes when it enters the inside, it is less likely to generate bubbles, making it difficult for bumping to occur, and part of the wastewater does not scatter to the treated water side, and it does not occur on the liquid surface. In the evaporator, combined with the use of an antifoaming agent, strike the bubbles with falling water to eliminate them. Foaming bumping can be prevented, event,
When foaming occurs and it reaches the limit, it can be detected and displayed by the foaming detector, and the heating of the evaporator can be stopped to cope with it, so that clear and evaporated water can always be obtained efficiently and safely.

[0006]

EXAMPLE An example of the present invention will be described with reference to the example of FIG. 1. A drainage inflow pipe 1 into which wastewater containing a foaming agent serving as raw water flows is provided, and the drainage from the drainage inflow pipe 1 is heated under vacuum. 2, the evaporator 3 for heating and evaporating the water is communicated with the evaporator 3 via the gas-liquid separating section 4, for example, an emiliator so that the water evaporated in the evaporator 3 is introduced, and the evaporated water is cooled by the cooling pipe 5. A waste water treatment device equipped with a condensing can 6 that is cooled and condensed by means of the above to collect as treated water, wherein the opening end 7 of the waste water inflow pipe 1 is disposed above the liquid surface of the evaporating can 3 and the evaporation is performed. A foaming detector 8, for example, an electrode-type liquid level controller, and other liquid level detectors are provided on the ceiling of the can to communicate with the alarm display unit 9 to provide a wastewater treatment device.

The drainage inflow pipe 1 is connected to a defoaming agent supply pipe 11 connected to a defoaming agent tank 12 and has an open end 7 which is opened in the evaporator 3 in an upward or downward direction. The vertical pipe 10 is provided so that the drainage flowing into the evaporator 3 is discharged into the vapor phase and can be dropped onto the liquid surface. The drainage inlet pipe 1 is provided with the liquid surface provided on the evaporator 3 A water supply valve 14 that is controlled to open and close by a detector 13 is provided, and the evaporation capacity can be controlled by adjusting the water supply amount.

Further, the condensed water tank 15 has a circulation system passage 18 having a water supply pump 17, and the circulation system passage 18 is provided.
The ejector 19 provided in the above is connected to the evaporating can 3 by a pipe 16 and provided as a vacuum generating mechanism, which serves to maintain the vacuum in the evaporating can 3 and is bypassed to the circulation system path 18 to recover a treated water flow path. 20 is provided via a valve 21.
In this case, the valve 21 is preferably connected to the liquid level detector 22 in the condensed water tank 15 to control the opening / closing operation.

In FIGS. 1 and 2, reference numeral 23 is a concentrated water discharge pipe provided in the evaporator 3. 24 is a heat pump, 25
Is a drainage storage tank, which is connected to the evaporation can 3 by the drainage inflow pipe 1 so that the drainage is supplied to the evaporation can 3 by head pressure or pump pressure. 26 is a concentrated water tank.

The foaming detector 8 installed above the evaporation can 3 detects the limit of the amount of foaming even if the liquid in the evaporation can 3 foams and issues an alarm, and an alarm display 9 is provided. Then, the heating of the evaporator 3 is stopped so as not to cause a bumping accident by extracting it from the discharge pipe 23, but instead of manual discharge, a valve provided in the discharge pipe 23 is linked to stop heating of the evaporator by foaming detection. You can also open it. The heating stop mechanism of the evaporator 3 is configured so that the heat pump 24 is stopped by the detection of the foaming detector 8, that is, the power is turned off.

In the embodiment of FIG. 3, the drainage inflow pipe 1 is
A vertical pipe 10 is provided in the evaporator 3 to open the opening end 7 above the liquid surface. (A) is an example in which the opening end is provided from above to below, and (b) is an example in which it is introduced from below. The opening end 7 is directed downward, but it may be blown upward, and in this case, as shown in (c), the baffle plate 27 provided above the liquid surface in the evaporator 3 is provided with an opposed opening. The morphology is also effective in releasing the expanding gas into the gas phase. In any case, if the tip of the drainage inflow pipe 1 is made higher than the liquid level in the can of the evaporator 3, the gas that has expanded rapidly will separate from the drainage and escape into the gas phase before being discharged. Since most of the gas has escaped when it enters the liquid in the can, bubbles are less likely to occur due to it, and bumping does not easily occur, and part of the wastewater does not scatter to the treated water side. In this way, by installing the tip of the drainage inflow pipe 1 above the liquid surface of the evaporation can 3, it is possible to prevent foaming and bumping in the can in combination with the use of the defoaming agent, and to always obtain a clear evaporated water. Obtainable.

[Embodiment 1] The results of treating the cleaning drainage discharged from the water cleaning device after mounting the printed circuit board with this device are as follows. The wastewater contains a surfactant, a foaming agent such as glycol ether, flux, and pine resin. Operating conditions Vacuum degree: 20 to 30 Torr Amount of treated water: 20 l / h Defoaming agent injection rate: 4.5 g / l-Drainage Operation results Table 1

[0013]

[Table 1]

[Embodiment 2] The results of treating the waste water from the cleaning device for cleaning the oil attached to the mechanical parts with the detergent and the water with this device are as follows. Wastewater contains detergent and oil. Operating conditions Vacuum degree: 20 to 30 Torr Amount of treated water: 10 l / h Defoaming agent injection rate: 1 g / l-Drainage Operation results Table 2

[0015]

[Table 2]

[0016]

Industrial Applicability The present invention comprises a drainage inflow pipe into which wastewater containing a foaming agent flows, and an evaporation can for heating the drainage from the drainage inflow pipe under a vacuum by a heating pipe to evaporate water. In a wastewater treatment device equipped with a condensing can, which is communicated through a gas-liquid separating member so that the water vaporized in the evaporator can flow in, and which is condensed and condensed by a cooling pipe to be recovered as treated water, The open end of the inflow pipe is arranged above the liquid surface of the evaporator, and a foaming detector is provided on the top of the evaporator to communicate with the alarm display section, so that the surfactant in the evaporator can be removed. During the purification process of wastewater containing water, the rapidly expanding gas in the wastewater flowing in from the wastewater inflow pipe separates from the wastewater and escapes into the gas phase before hitting the liquid surface, and the wastewater enters the liquid inside the evaporator. Sometimes most of the gas escapes, so That to a part of the waste water is hardly caused less bumping generation of bubbles can not be scattered in the processing water side, even beating a drop water bubbles about to occur on the liquid surface,
Combined with the use of the defoaming agent, it is possible to prevent foaming bumping in the evaporator, and if foaming occurs and the limit is reached, the foaming detector can detect and display and the heating of the evaporator can be stopped. Since it is possible to deal with it, it is possible to always obtain clear evaporatively treated water efficiently and safely, to perform wastewater treatment safely, to have a simple configuration, easy maintenance and security, and a compact and economical device. .

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a system in one use state showing an embodiment of the present invention.

FIG. 2 is a schematic description of a main part of the example of FIG.

FIG. 3 is another embodiment of the evaporation can of the example of FIG.
(B) (c) It is a longitudinal explanatory view, respectively.

[Explanation of symbols]

1 Drainage Inflow Pipe 2 Heating Pipe 3 Evaporation Can 4 Gas-Liquid Separation Member 5, 5 ₁ Cooling Pipe 6 Condensing Pipe 7 Opening End 8 Foaming Detector 9 Alarm Display 10 Vertical Pipe 11 Defoaming Agent Supply Pipe 12 Defoaming Agent Tank 13 Liquid Level Detector 14 Water Supply Valve 15 Connection Pipe 16 Piping 17 Water Pump 18 Circulation System Channel 19 Ejector 20 Recovery Channel 23 Concentrated Water Discharge Pipe 24 Heat Pump

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[Procedure amendment]

[Submission date] July 7, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Title of invention

[Correction method] Change

[Correction content]

[Title of Invention] Wastewater treatment device

Claims (3)

[Claims] 1. An evaporation can, comprising: a drainage inflow pipe into which a wastewater containing a foaming agent flows, and heating the drainage from the drainage inflow pipe by a heating pipe under vacuum to evaporate the water content; and an evaporation can in the evaporation can. In a wastewater treatment device equipped with a condensing can that is communicated through a gas-liquid separation member so that the moisture that has been introduced flows in, and the evaporated moisture is cooled and condensed by a cooling pipe and collected as treated water,
A wastewater treatment apparatus, wherein the open end of the wastewater inflow pipe is arranged at a position above the liquid surface of the evaporator, and a foaming detector is provided on the top of the evaporator to communicate with an alarm display. 2. A vertical pipe, wherein the drainage inflow pipe is connected to a defoaming agent supply pipe connected to a defoaming agent tank, and has a vertical pipe having an opening end opened upward or downward in an evaporator. The wastewater treatment equipment according to claim 1. 3. The waste water treatment apparatus according to claim 1, wherein the waste water inflow pipe is disposed so as to face an opening end of a baffle plate provided above the liquid surface in the evaporator.