JP4332264B2 - Drain pumping device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a drain pumping device for discharging drain discharged from a pneumatic device and collected in an open-air tank or pit to the outside.
[0002]
[Prior art]
Drains discharged from pneumatic equipment such as air compressors contain oil components derived from lubricating oil, and these oil components must be treated to maintain water quality. Usually, the drain discharged from each device is collected in an open air tank or pit, temporarily stored, and then pumped to an oil / water separator such as a downstream oil adsorption tank to adsorb residual oil by an adsorbent.
[0003]
Japanese Patent No. 2761463 discloses a drain pumping device that can operate even with a relatively small amount of drain in the tank or pit and is less affected by air contained in the drain. FIG. 2 shows a cross-sectional view of a drain pumping device similar to that described in the specification. In the figure, reference numeral 1 denotes a drain pit for storing drains generated from the respective coolers, and a pumping tank 2 having a bottom 2a formed in a tapered shape is installed at an angle at the bottom of the drain pit 1. The discharge port 3 of the pressure feed tank 2 branches into a drain discharge port 4 and a drain injection port 5. The drain discharge port 4 communicates with a drain discharge portion and further downstream oil adsorption tank (not shown) through a tube, and the drain injection port 5 is connected to a check valve (check valve) 6. The drain inlet 5 is substantially perpendicular to the outlet 3 and is connected to the vicinity of the outlet.
[0004]
The check valve 6 includes a main body 7 having an open ceiling and a bottom, a cylindrical valve 8 that opens and closes the open portion of the ceiling by moving up and down in the main body 7, and a side surface of the valve 8. It consists of an open hole 9. The upper part of the pressure feed tank 2 is connected to an electromagnetic three-way valve 10 via a tube (not shown). The electromagnetic three-way valve 10 supplies atmospheric pressure or compressed air to the pressure feed tank 2. The electromagnetic three-way valve 10 is controlled by an output signal of a timer or a level sensor (not shown) installed in a pit and a tank, and operates periodically or at any time. The compressed air supplied to the electromagnetic three-way valve 10 is branched directly from the compressed air piping of the pneumatic equipment.
[0005]
[Problems to be Solved by the Invention]
The drain pumping device is less affected by the air contained in the drain than the suction type pump, and since the pumping tank 2 is inclined, it can be operated even when there is little drain in the pit. Although it is suitable as a drain pressure feeding device, it is relatively expensive because it requires a control device for supplying compressed air to the pressure feeding tank 2 and a power source for driving it.
Further, in this apparatus, compressed air for driving the pressure feed tank 2 is directly supplied from the main piping system, so that an extra load is applied to the air compressor or the like, while the drain pit or the upstream side of the tank is used for drain pressure delivery. Since the compressed air was discharged into the atmosphere in vain, improvement was desired from the viewpoint of energy saving.
[0006]
[Means for Solving the Problems]
The invention described in claim 1 of the present application is a drain pumping device that uses compressed air to send drain from an open-air tank or pit to an oil-water separator such as an oil adsorption tank. A drain characterized by connecting a gas-liquid separator having a gas discharge pipe at an upper portion between a gas tank and a pit and connecting an exhaust system of the gas discharge pipe to a gas inflow pipe of the drain pumping device The above problem is solved by the pressure feeding device.
According to a second aspect of the present invention, the gas-liquid separator is a swirl-separation type and is formed of a cylindrical housing, and a drain inlet pipe inclined laterally with respect to the housing radial direction at an upper side surface of the housing. A drain outlet pipe is provided at the lower part of the housing, and an air outlet pipe is provided at the center of the upper surface. The drain pumping device according to claim 1 solves the above problem.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings. In FIG. 1, 1 is a drain pit, 2 to 9 are drain pumping devices similar to those described in the above patent specification, 2 is a pumping tank, 3 is a discharge port of the pumping tank 2, 4 is a drain discharge port, 5 is a drain inlet, 6 is a check valve (check valve) connected to the drain inlet 5, and 7, 8, and 9 are a check valve 6 body, a valve, and a hole opened in the side of the valve, respectively. Show. Reference numeral 11 denotes a pneumatic device, and 12 denotes a drain trap. Reference numeral 20 denotes a gas-liquid separator for separating compressed air ejected from the drain trap into the tank and drain and sending only the drain to the drain pit. The gas-liquid separator 20 in this figure is a so-called swivel separation type, in which a drain inlet pipe 22 inclined to the side with respect to the radial direction of the housing is formed on the upper side surface of the cylindrical housing 21, and a drain outlet pipe 23 is formed on the lower side surface. Provided and connected to the drain trap 12 and the drain pit 1, respectively. The drain outlet pipe 23 is provided with a throttle 23 a for maintaining the pressure in the gas-liquid separator 20. An air outlet pipe 24 communicating with the pressure feeding tank 2 is provided at the center of the upper surface of the housing 21 through a connection hole 21a.
[0008]
[Action]
Compressed air and drain discharged from the drain trap 12 are inclined tangentially from the drain inlet pipe 22 and flow into the gas-liquid separator 20, and swirl along the side surface of the housing 21 by the tangential momentum, and are kept for a certain period After staying in 21 and losing momentum, it flows toward the upper air outlet pipe. During that time, the drain contained in the compressed air falls to the bottom of the housing 21 by its own weight, and only the drain gently flows out from the drain outlet pipe 23 on the side surface toward the drain pit 1. Due to the restriction 23a of the drain outlet pipe 23, the inside of the gas-liquid separator 20 and the pressure feed tank 2 is kept at a high pressure until all of the drain flows out.
[0009]
The drain once stored in the drain pit 1 flows into the pressure feed tank 2 through the filter of the check valve 6 and the drain inlet 5. Since the pressure in the pressure tank 2 is relatively low when the drain trap 12 is closed, the drain is sucked up to a certain water level. However, when the drain trap 12 is opened, it is accumulated by the action of compressed air supplied from the gas-liquid separator 20. Push the drain down. At this time, pressure is also applied to the drain in the vicinity of the injection port 5, and the valve 8 of the check valve 6 closes the opening by the pressure to prevent the drain and compressed air from being discharged to the drain pit 1. The oil is directed toward the outlet 4 and is sent from the drain discharge port 4 to an oil adsorbing tank (not shown) through a tube, and the residual oil remaining in the form of an emulsion is adsorbed by the oil adsorbing material. When the drain trap 12 is closed and compressed air is no longer supplied, the pressure in the pressure-feed tank 2 decreases and the drain is sucked again from the check valve 6. As a result, the drain discharge time from the drain trap 12 and the drain discharge time from the pressure feed tank 2 become substantially equal. Therefore, if the throttle 23a is adjusted, an amount of drain that is always in proportion to the amount flowing into the drain pit 1 is discharged. Can be done.
[0010]
As the gas-liquid separator 20, in addition to the swivel separation type as shown in FIG. 1, the drain inlet pipe projects from the center of the upper part of the housing in the same manner as that described in JP-A-8-327214. It is also possible to use a collision-separation type in which an air outlet pipe communicating with the air outlet pipe is provided in the periphery thereof. In such a configuration, the drain is ejected toward the bottom of the housing, and after colliding with the bottom or the drain, the drain flows toward the upper air outlet pipe while weakening the force with the drain at the rear. Further, the drain pumping device is not limited to the one in this embodiment as long as it is of a type that sends out the drain by compressed air.
Even if the gas-liquid separator 20 is temporarily filled with drain and drainage flows from the air outlet pipe 24 into the pressure feed tank 2, the oil is treated by the adsorbent in the oil adsorption tank, and there is a problem with the quality of the drainage water. Therefore, the volume of the gas-liquid separator 20 may be small.
Although only one set of pneumatic equipment 11, drain trap 12, and gas-liquid separator 20 is shown in the figure, it is of course possible to provide a plurality of sets of these.
[0011]
Since the drain pumping device operates in conjunction with the operation of the drain trap 12, that is, the discharge of the drain, the water level in the drain pit 1 rises above a certain level without providing a control means such as an independent timer or sensor device. There is nothing. In order to save compressed air, it is preferable to close the drain trap 12 before the drain in the gas-liquid separator 20 runs out. On the other hand, the drain trap 12 is opened for a certain time after the completion of the pumping of the drain to the gas-liquid separator 20. If compressed air is sent, sufficient air pressure can always be supplied to the drain pressure feed tank 2.
[0012]
【The invention's effect】
In the drain treatment system of the present invention, the discharged drain is temporarily stored in an open-drain type drain pit, so that the downstream oil-water separator can be efficiently operated.
In addition, the compressed air discharged from the drain trap together with the drain is used as the compressed air source of the pressure feeding device, and an extra load is not given to the pneumatic equipment, which contributes to energy saving.
Further, since the drain pumping device operates in conjunction with the operation of the drain trap, it is not necessary to provide an independent timer device or sensor for managing the water level of the separation tank 1, and a simple configuration can be achieved.
[Brief description of the drawings]
FIG. 1 is an overall view of a drain pumping device and a drain pit according to the present invention.
FIG. 2 is a schematic view of a conventional drain pumping device.
[Explanation of symbols]
1 Drain pit 2 Pressure tank 12 Drain trap 20 Gas-liquid separator 21 Housing 22 Drain inlet pipe 23 Drain outlet pipe 24 Air outlet pipe

Claims (2)

A drain pumping device for sending drain from an open-drain type drain pit or tank to the oil-water separator using compressed air, wherein a gas-liquid separator is connected between the drain trap outlet and the drain pit or tank, A drain pumping device, wherein an exhaust system of a gas-liquid separator is connected to a gas inflow pipe of the drain pumping device. The gas-liquid separator is a swivel separation type and is formed of a cylindrical housing, and a drain inlet pipe inclined to the side with respect to the radial direction of the housing is provided at an upper side of the housing, and a drain outlet pipe is provided at the lower part of the housing. The drain pumping device according to claim 1, wherein an air outlet pipe is provided at a central portion of the upper surface.

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