JP3477583B2 - Oil separation device for oil-filled compressor and method for measuring oil content in discharged gas - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil separation device for a refueling type compressor and a method for measuring oil content in a discharge gas. The present invention relates to an oil separation device equipped with a means capable of measuring.

[0002]

2. Description of the Related Art In a refueling type compressor, oil is injected into a compression part in order to remove compression heat generated during a compression process and lubricate the compression part. Therefore, since a part of the injected oil will be entrained in the discharge gas, conventionally, an oil separation device equipped with an oil separator and a plurality of stages of oil separation filters is provided in the latter stage of the oil supply compressor. It is installed to separate the oil content in the discharge gas. In order to reduce the consumption of oil and gas, the oil separated by this oil separation device is generally automatically discharged by a level sensor, a solenoid valve or the like and returned to the compressor.

Up to now, in the above-mentioned oil separation device, the oil contained in the processing gas discharged from the oil separation device has been measured, but the oil concentration range is naturally targeted at the low concentration region. It was something to do.

[0004]

However, the oil separation device separates and removes the oil content in the gas from several thousands weight ppm to 0.1 weight ppm order in terms of oil content, and is a multi-stage oil content separation filter. When the oil concentration at the inlet of the equipment exceeds the design conditions of the equipment, the oil concentration at the outlet side of the oil separation filter at the final stage also increases and the downstream equipment is contaminated with oil. I will end up.
In order to avoid this, it is necessary to measure a high-concentration oil content on the inlet side of the device, but at present, an appropriate measuring means has not been established.

Therefore, the present invention is capable of accurately measuring the oil concentration in a relatively high concentration region in an oil separation device provided in the latter stage of an oil supply type compressor, and by using this, abnormality of the device can be detected early. It is an object of the present invention to provide an oil separation device and a method for measuring oil content in discharge gas, which has a configuration capable of detecting the oil content.

[0006]

In order to achieve the above-mentioned object, an oil separation device in an oil supply type compressor of the present invention is
A small-diameter oil reservoir is connected to the bottom of the oil separation filter, and a pair of high and low level sensors for detecting the liquid level of oil are provided in the oil reservoir, and the oil is opened and closed by the signals from both level sensors. The oil discharge valve for discharging the oil in the reservoir and the time required from the closing to the opening of the oil discharge valve are measured, and the unit is calculated from the required time, the interval between the level sensors, and the sectional area of the oil reservoir. An oil content measuring means for calculating an oil content per unit time is provided.

Further, the method for measuring the oil content in the discharge gas in the oil supply type compressor of the present invention is to measure the liquid level of the oil accumulated in the oil reservoir provided at the bottom of the oil separation filter for separating the oil content in the discharge gas. Detecting with a pair of high and low level sensors, the oil discharge valve is opened and closed according to the signals of both level sensors to discharge the oil in the oil reservoir, and the time required from the closing of the oil discharge valve to the opening of the oil discharge valve The amount of oil contained in the discharge gas is calculated from the interval of the level sensor, the cross-sectional area of the oil reservoir, and the amount of discharge gas. Further, the oil separation filter is determined from the change in the opening / closing time interval of the oil discharge valve. It is characterized by detecting abnormalities in upstream equipment.

[0008]

[Operation] The interval between both level sensors in the oil reservoir of the oil separation filter is P [cm], and the inner diameter of the oil reservoir is D [c].
m], the oil amount V [cm ³ ] accumulated in the oil reservoir is
(Π / 4) D ² P. Also, the required time is Δt [se
c], the amount of increase in oil content per unit time Va [cm]
³ / sec] is calculated by V / Δt. Further, the gas flow rate is m [g / sec], the inlet oil concentration of the oil separation filter is Cin [g / g], and the outlet oil concentration is Co.
If ut [g / g] and the oil density are ρ [g / cm ³ ], the relationship Δtm (Cin−Cout) = V · ρ is established, and usually Cin >> Cout, so Co
If ut is ignored, the inlet oil content concentration can be calculated by (V · ρ) / (Δt · m). At this time, by measuring or calculating the outlet oil content concentration Cout, the measurement accuracy of the inlet oil content concentration Cin of the oil content separation filter can be improved.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in more detail based on an embodiment shown in the drawings. FIG. 1 is a system diagram showing a configuration of an oil separation device of the present invention, which is provided with three stages of oil separation filters 10, 20, 30. Compressor 1
The gas compressed in step 1 is introduced into the oil separator through the oil separator 2 and the aftercooler 3, and is sequentially processed by the three-stage oil separator filters 10, 20, 30 and the adsorber 4 to remove the contained oil. After that, it is sent to the equipment on the downstream side. The oil is supplied to the compressor 1 by cooling the oil in the oil separator 2 with an oil cooler 5 and pumping it with a pump 6.

Oil separation filters 10, 20, 30
In the same manner as the conventional one, the gas introduction pipes 11, 21, 31 provided with the filter portions 12, 22, 32 at the tips thereof are arranged inside the containers 13, 23, 33. The oil content captured by the parts 12, 22, 32 falls to the bottom of the container, and the gas from which the oil content has been removed is led to the gas introduction pipes 21, 31 at the next stage or the introduction pipe 4a of the adsorber 4.

Each of the above oil separation filters 10, 20, 3
Oil reservoirs 14, 24, 34 having a diameter smaller than that of each of the containers 13, 23, 33 are connected to the bottom of the container 0, and the separated oil reservoirs are attached to the bottoms of the oil reservoirs 14, 24, 34. Oil return pipes 7 for recovering the oil to the suction side of the compressor 1 are respectively connected.

Further, in each of the oil reservoirs 14, 24, 34, a level at which the oil level (oil level) accumulated in the oil reservoirs is detected at two points, a high position (H) and a low position (L). Sensors (LS) 15, 25, 35 are provided respectively, and between the bottoms of the oil reservoirs and the oil return pipe 7 are provided for oil discharge which is opened and closed by the signals of the level sensors 15, 25, 35. Electromagnetic valves 16, 26 and 36 are provided respectively.

Further, in the operation circuit of the solenoid valves 16, 26, 36, the oil reservoirs 14, 20, 30 of the oil separation filters 10, 20, 30 are based on the intervals of opening and closing operations of the solenoid valves 16, 26, 36. The amount of oil accumulated in 24, 34 is calculated, and the concentration of oil in the gas introduced into each oil separation filter 10, 20, 30 is calculated from this, and the state of the compressor 1 and the state of the oil separation filter on the upstream side are calculated. An oil content measuring means 8 for monitoring the oil content is provided.

For example, in the first oil separation filter 10, when the level sensor 15 detects that the oil level in the oil reservoir 14 is at a high position, the solenoid valve 16 opens and the oil reservoir 14 is opened. The oil is discharged to the oil return pipe 7. When the level sensor 15 detects that the oil level in the oil sump portion 14 has become low as the oil discharge progresses, the solenoid valve 16 is closed and trapped inside the oil sump portion 14 by the filter portion 12. The oil starts to collect.

That is, as shown in FIG. 2, the solenoid valve 16
The oil level in the oil reservoir 14 gradually rises from the time when is closed, and when the oil level reaches the high position of the level sensor 15, the solenoid valve 16 opens and the oil level gradually descends. Then, when the oil level falls to the low position of the level sensor 15, the solenoid valve 16 is closed again, and the oil level rises. As described above, the oil level in the oil sump portion 14 is changed to the low position (L) and the high position (H) of the level sensor 15 as the solenoid valve 16 is opened and closed.
Changes between and.

Therefore, the time from when the oil level is in the low position of the level sensor 15 and the solenoid valve 16 is closed until when the oil level is in the high position of the level sensor 15 and the solenoid valve 16 is opened. It is possible to measure the oil content per unit time by measuring.

Here, the interval between the low position (L) and the high position (H) of the level sensor 15 is P [cm], and the oil reservoir 1
If the inner diameter of 4 is D [cm], the amount of oil V [cm] accumulated in the oil reservoir 14 between the time the electromagnetic valve 16 is closed and the time it is opened.
³ ] becomes (π / 4) D ² L. Further, if the time required from the closing of the solenoid valve 16 to the opening of the solenoid valve 16 is Δt [sec], the average oil content increase amount V in the oil reservoir 14 per unit time is V.
a [cm ³ / sec] is obtained by V / Δt. The average oil content increase amount Va represents the oil content separated from the gas by the oil separation filter 10 per unit time, and corresponds to the difference between the inlet oil content concentration and the outlet oil content concentration in the oil content separation filter 10.

That is, the inlet oil concentration in the oil separation filter 10 is Cin [g / g], the outlet oil concentration is Cout [g / g], and the oil density is ρ [g / cm ³ ].
Then, the relationship of Δtm (Cin−Cout) = Vρ is established. Normally, the outlet oil content concentration Cout is sufficiently smaller than the inlet oil content concentration Cin (Cin >> Cou
t), Cout can be ignored, and from the above equation, the inlet oil concentration Cin is (V · ρ) / (Δt · m)
Can be calculated by At this time, the accuracy of measurement of the inlet oil content concentration Cin in the oil content separation filter 10 is improved by substituting the inlet oil content concentration in the oil content separation filter 20 obtained by the same operation for the outlet oil content concentration Cout of the oil content separation filter 10. be able to.

Further, by decreasing the diameter of the oil reservoir 14, the rate of change of the oil surface can be increased, and even a small amount of oil can be measured reliably, so that the oil separation set in the steady state can be performed. By setting the diameter of the oil reservoir 14 according to the amount, the measurement accuracy can be improved.
For example, the oil reservoir 14 of the first-stage oil separation filter 10
The diameters of the oil reservoirs 24 in the second stage and the oil reservoirs 34 in the third stage are sequentially reduced with respect to the diameter of
It is possible to set the amount of increase in oil content at 4, 24, and 34 in the optimum range, and the oil separation filters 10, 20, and 3 can be set.
The amount of oil separated by 0, that is, the concentration of oil in the gas introduced into each oil separation filter 10, 20, 30 can be measured accurately.

On the other hand, as long as the refueling compressor 1 is in steady operation, the oil content contained in the gas discharged from the compressor 1 is substantially constant, and the oil separation filters 1
If 0, 20, and 30 are functioning normally, the amount of oil separated from each is also substantially constant. Therefore, if each device is operating normally, each oil separation filter 10, 20, 3
The required time Δt from the closing of the solenoid valves 16, 26, 36 of 0 to the opening of the solenoid valves is also substantially constant.

Therefore, the oil content measuring means 8 monitors the change in the required time Δt in each of the oil separation filters 10, 20, 30. For example, when the required time Δt becomes long, the compressor 1 and the pump 6 are abnormal. It is conceivable that the oil content concentration in the gas introduced by the above-mentioned method has decreased, or the oil separation ability of the filter part of the oil separation filter has decreased. Further, when the required time Δt becomes short, it means that the oil content concentration in the introduced gas has increased. Therefore, the oil content separation capability of the oil separation filter on the upstream side may be deteriorated or the compressor 1 may be abnormal. Can be detected.

In this way, by measuring the amount of increase in the separated oil content accumulated at the bottom of the oil separation filter,
The oil concentration in the gas can be easily measured over a wide concentration range. Further, by monitoring the operation time of the valve for discharging the oil accumulated in the oil reservoir, it is possible to promptly detect the abnormality of the oil separation filter and the abnormality of the upstream equipment. In particular, by forming the portion where the separated oil is accumulated to have a small diameter, it is possible to more accurately detect the change in the oil surface and significantly improve the measurement accuracy.

Therefore, the oil contained in the gas can be reliably separated and removed by the oil separator according to the design conditions, and the downstream equipment can be prevented from being contaminated with oil. When the refueling compressor is operated continuously for a long time in the operation of the refrigerator, by applying the above configuration to all the oil separation filter parts, it is possible to continuously monitor the presence or absence of abnormalities in each device and to stabilize the operation. The operating state is obtained.

The number of oil separation filters installed may be one or more, and an oil separation filter of an appropriate size may be connected according to the amount of gas discharged from the compressor and the amount of oil to be separated and removed by the oil separation device. Just set it up. Further, the oil reservoir can be formed by an ordinary pipe body, but its shape can be changed according to the amount of oil, etc., for example, the cross-sectional area of the level sensor portion and the cross-sectional area between the level sensors. And may be changed, and the cross section may be other than circular.

[0025]

As described above, according to the present invention,
In the oil separation device connected to the oil-filled compressor, the oil concentration in the discharge gas can be measured in a wide range from the high concentration region to the low concentration region, and abnormalities in the compressor and oil separation device can be detected early. can do. In particular, by forming the oil reservoir at the bottom of the oil separation filter small, the accuracy of measuring the oil concentration can be greatly improved.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing the relationship between changes in the oil level of the oil reservoir and the open / closed state of the valve.

[Explanation of symbols]

1 ... Compressor, 4 ... Adsorber, 7 ... Oil return piping, 8 ... Oil content measuring means, 10, 20, 30 ... Oil separation filter, 1
4, 24, 34 ... Oil reservoir, 15, 25, 35 ... Level sensor, 16, 26, 36 ... Solenoid valve

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F04B 39/16

Claims (3)

(57) [Claims] 1. An apparatus for separating an oil component contained in a discharge gas of an oil supply type compressor by an oil separation filter, wherein a small-diameter oil reservoir is connected to the bottom of the oil separation filter, and the oil reservoir is connected to the oil reservoir. A pair of high and low level sensors that detect the liquid level of the oil are provided, and an oil discharge valve that opens and closes according to the signals of both level sensors to discharge the oil in the oil sump, and a valve from the closed to open state of the oil discharge valve. An oil content measuring means for measuring an amount of oil content per unit time from the required time, the interval between the both level sensors, and the cross-sectional area of the oil sump portion. Oil separation device in compressor. 2. A method for measuring the oil content contained in the discharge gas of an oil supply type compressor, the liquid level of the oil collecting in an oil reservoir provided at the bottom of an oil separation filter for separating the oil content in the discharge gas. The height is detected by a pair of high and low level sensors, and the oil discharge valve is opened / closed by the signals of the both level sensors to discharge the oil in the oil reservoir, and the time required from the closing of the oil discharge valve to the opening thereof. A method for measuring oil content in discharge gas in a refueling compressor, comprising calculating the amount of oil contained in the discharge gas from the distance between the level sensors, the cross-sectional area of the oil reservoir, and the amount of discharge gas. 3. The oil content in the discharge gas in the oil supply type compressor according to claim 2, wherein an abnormality in the oil separation filter and the equipment on the upstream side is detected from the change in the opening / closing time interval of the oil discharge valve. Measuring method.