JPS6287264A - Discharge method in oil purifier - Google Patents

Abstract

PURPOSE:To change the opening and closing time of a valve cylinder and to regulate the discharge amt. of sludge and separated water by changing the pressure of working water on the basis of the signal of a water content detector at the purified oil outlet passage of a rotor. CONSTITUTION:With respect to the method for purifying oil by a centrifugal separator contg. plural separation plates in its rotor, the water content is detected at an optional position of the purified oil B outlet passage of the rotor 1 by the change in the dielectric constant. The signal is transmitted to a controller 6 wherein the water contents in the purified oil B are compared and a selector valve 9 is changed over to the compressed air E2 side at pressure P2 in case of abnormality. Consequently, the compressed air E2 at pressure P2 is supplied to a water tank 8, a cylinder 3 is operated for a longer time than usual, and the sludge C and the water D at the space part are discharged.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a method for cleaning oil using a centrifugal separator having a plurality of separators built into a rotating body, and more specifically to a method for cleaning oil by cleaning oil using a centrifugal separator having a plurality of separation plates built into a rotating body. and a method for regulating the amount of separated water discharged.

Prior Art) With the rapid rise in oil prices since 1999 and the increase in demand for light oils (ganlin, kerosene, diesel oil, etc.), the quality of fuel oil supplied to ships in particular has been deteriorating.

Fuel oil that has deteriorated in quality and quality tends to have higher specific gravity and higher viscosity, and centrifugal separators are often used to purify this oil. Especially centrifuges with built-in separators (
BACKGROUND ART Separation plate centrifuges (hereinafter referred to as separator plate centrifuges) are widely used because they have high performance in separating impurities such as moisture and sludge, are easy to maintain, and can be operated automatically. The separation plate type centrifuge is a three-layer centrifuge (hereinafter referred to as a burifier) that separates the oil into three layers: light liquid (clean oil) - heavy liquid (separated water) - solid matter (sludge) depending on the properties of the oil to be processed. ), and as a double-layer centrifuge (hereinafter referred to as a "talarifier") that separates light liquid (clean oil) and impurities (heavy liquid and solids) into two layers. The invention relates to the latter talarifier.

Problems to be Solved by the Invention) In conventional burifiers, the difference in specific gravity between oil and water is small, and the specific gravity of the oil to be treated is 099/ (at /j/ II
℃) or higher, the separation interface between the clean oil and separated water in the rotating body becomes unstable. Therefore, the adjustment plate that adjusts the position from which the separated water is extracted must be replaced frequently, making stable operation difficult.

In addition, in the case of the above condition, a tarlarifier is usually used, but since the conventional tarlarifier cannot continuously discharge the separated water, if the separated water accumulates beyond the allowable space inside the rotating body, the clean oil will be removed. There was a drawback that moisture could get mixed into the clean oil. Further, if the operation is continued under the above conditions, the separation boundary surface will approach the separation plate layer inside the rotating body, and the separation effect will be significantly deteriorated. To compensate for the above drawbacks, there is a device that extremely shortens the opening and closing time of the valve 7 cylinder of the rotating body and frequently discharges part of the sludge and separated water accumulated in the rotating body. This can lead to faster wear and oil leakage from the rotating body, and because the discharge interval, discharge time, and working water pressure are fixed, only a certain amount of water is discharged at all times, and the sludge and moisture contained in the liquid to be treated can be easily discharged. If the amount fluctuates, it has drawbacks such as not being able to follow it.

(Means for Solving the Problem) The present invention is directed to the above-mentioned! ■It was done out of consideration for the circumstances;
In the method of cleaning oil using a separator plate centrifuge, the water pressure of the operating water that opens and closes the valve and cylinder of the rotor is controlled by a signal from a moisture detection device installed in the 7/I purified oil outlet flow path of the rotor. This is a method for discharging an oil cleaning device, characterized in that the opening and closing time of the valve cylinder 7 is changed by changing the pressure, and the discharge amount of sludge and separated water is adjusted. In the above-mentioned invention, normally, the valve/sump/der is opened and closed according to the discharge interval and discharge time set by a timer as in the conventional method, and the operation for discharging sludge and the like is also used. The moisture detection device may be one that detects the difference in physical properties between oil and moisture, such as a capacitance type or a turbidity type.

As a method for changing the pressure of the working water, an air pressurized water tank may be used to control the supply air pressure, or a plurality of working water supply systems having different pressures may be installed and switched.

Effect) When there is a lot of water in the oil to be treated, or if it becomes too much, the separated water accumulated in the rotating body will reach the separating plate layer.
The water level in the oil race rises rapidly. This phenomenon is detected by the moisture detection device, and a signal is sent via the detection device controller to the automatic control panel, which changes the pressure of the working water that opens and closes the valve cylinder to a level higher than the normal pressure. As the working water pressure increases, the amount of working water discharged per unit time from the open valve water discharge nozzle also increases, but a larger amount of working water is actually supplied and the operating time of the working water also becomes longer. Therefore, the opening time of the valve cylinder is longer than usual, and the amount of discharge is also increased.

Embodiments) The present invention will be described in detail below based on embodiments shown in the drawings. FIG. 1 is a system diagram showing one embodiment of the present invention, and FIG. 1 is a longitudinal sectional view of the main parts of a rotating body.

1 is a rotating body of a separator plate type centrifugal separator, which includes a plurality of layered separator plates and rotates at a speed of several thousand revolutions per minute. Reference numeral 3 denotes a valve cylinder which is provided at the bottom of the rotating body / and is slid up and down by a pilot valve mechanism operated by working water F to open and close the discharge hole 1 for discharging the sludge separated water. In the sludge discharge process by opening and closing the valve cylinder, first, working water F is introduced into the valve-closing hydraulic chamber lλ, and when the valve-closing hydraulic chamber /2 becomes full, it overflows and flows into the valve-opening hydraulic chamber 10. When the valve-opening water pressure chamber 10 is filled with working water F, the pilot valve l/ is slid in the opposite radial direction, and the gasket part 7 of the valve-closing water discharge nozzle/l is ruptured, causing a part of the valve-closing water to rotate. It flows out of the body and due to the pressure inside the rotating body, the valve cylinder 3
is pushed down, the discharge hole opens, and the sludge is discharged. The working water F in the open-valve hydraulic chamber IO is drawn out from the open-well water discharge nozzle /3, the seal part is sealed, and the working water F enters the closed-valve hydraulic chamber /,! The valve cylinder 3 is pushed up, the discharge hole is closed, and the sludge discharge process is completed. The above steps can be repeated at regular intervals using a timer.

j is a capacitance-type moisture detection device that detects the moisture content based on a change in dielectric constant, and is provided at an arbitrary position on the outlet path of the clean oil B. g is the operating water F in an air pressurized water tank.
is stored, and the operating water pressure is controlled by the pressure of the upper air. This is a switching valve that switches and sends air Fi/ at a pressure P/ and air E2 at a higher pressure P- to the water tank ♂. The liquid to be treated A is supplied into the rotating body from the stock solution inlet of the rotating body, and the supplied liquid to be treated QA is affected by centrifugal force and separation plate! is separated into clean oil B, sludge C, and separated water. The separated clean oil B rises between the separation plates and is led out from the outlet of the clean oil B, and the sludge C and separated water accumulate in the space S outside the ends of the separation plates.

In normal operation, when sludge C and separated water accumulate up to space S/, pressurized air E/ of pressure P/
A water tank! The valve cylinder 3 is opened with working water E/ having a pressure of P/, and the sludge C and separated water are discharged from the discharge hole by a space S1. Further, the above-described process is performed at preset discharge intervals by a timer provided in the automatic control panel 7. If there is a lot of water in the oil A to be treated, or if the water content increases due to changes in its properties, it will not be possible to keep up with the discharge interval by the timer, and the separated water will cross the space S2 and mix into the clean oil B. The amount of water in clean oil B is rapidly increased. A detection signal from a moisture detection device j provided in the clean oil outlet flow path is constantly transmitted to a detection device controller t and compared with a moisture amount within a set range. Therefore, when the above condition occurs, the relative permittivity increases rapidly, and the detection signal from the moisture detection device j is judged as an abnormal value by the detection device controller B, and the controller 2 directs the switching valve to the pressure air E2 side of the pressure P2. A switching signal is sent to the automatic operation panel 7. Pressure P, 2
By supplying pressurized air E2 to the water tank g, the pressure increases to P,! The valve cylinder 3 is opened for a longer time than usual using the working water El, and the sludge C and separated water corresponding to the space S/+82 are discharged from the discharge hole.

Effects) /) Unlike conventional burifiers, there is no need for strict selection of adjustment plates or frequent replacement, and it can easily follow fluctuations in the amount of water in the oil to be treated.

2) Unlike conventional tararifiers, separated water does not collect in an amount larger than the allowable space within the rotating body and mix into clean oil, reducing separation efficiency.

3) Regarding the method of adjusting the discharge amount (drainage time) of sludge and separated water during operation, the conventional method of changing the operating time of working water using a timer requires adjustment within 1 second, which is difficult, but this method The invention is easy because it uses a method of changing the operating time by changing the operating water pressure.

[Brief explanation of drawings]

FIG. 1 is a system diagram of an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of the main parts of a rotating body. /: Rotating body 1.2: Separation plate, 3: Valve cylinder, l: Discharge hole, ! : moisture detection device, t: detection device controller,
7: automatic control panel, g: water tank, 9: switching valve, 10: open valve hydraulic chamber, //: high lot valve, /λ: close valve hydraulic chamber, /
3: Open valve water discharge nozzle, /ri: Closed valve water discharge nozzle,
A: Oil to be treated, B: Clean oil, C: Sludge, D: Separated water, ESK/, E,! : Pressure air, F: Working water.

Claims (1)

[Claims] In a method for cleaning oil using a centrifugal separator that has a plurality of separation plates built into a rotating body and is equipped with a valve cylinder that is opened and closed by operating water, a moisture detection device provided in a clean oil outlet flow path of the rotating body A method for discharging an oil purifying device, characterized in that the opening/closing time of the valve cylinder is changed by changing the pressure of the working water in response to a signal from the device, thereby adjusting the amount of sludge and separated water to be discharged.