JPS59147614A - Process for capturing oil mist - Google Patents

Abstract

PURPOSE:To collect oil mist of fine particle size with high collecting efficiency in an inertial collision type oil mist collecting apparatus by providing at least two collecting apparatuses in series in the direction of the flow of the gas contg. the oil mist. CONSTITUTION:Rolling oil or cooling oil etc. scatters in the form of oil mist during rolling of a material 12 to be rolled by a rolling mill 10. Exhaust gas contg. the oil mist is collected by a mill hood 14 which is connected to a stack 18 by an exhaust gas duct 16. An upstream side dust collector 20 and a downstream side dust collector 22, both of an inertial collision type, are provided in series in the midway of the connecting line. The gas to be treated is fed to the upstream side dust collector 20 with 5-15m/sec flow rate to cause collision of fine oil mist with each other to grow the particle size of the mist. Then, the gas is fed successively to the downstream side dust collector 22 with 1-3m/sec flow rate to collect all of the oil mist. The exhaust gas contg. no oil mist is discharged from the stack 18.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an oil mist collection method, and more particularly to an oil mist collection method using the principle of inertial collision.

There are various types of oil mist collection devices, such as those of a filtration type, a water retention type, and an inertial collision type. However, although the filtration method has a high oil mist collection efficiency, it has the drawback of high pressure loss, high equipment costs, and a large amount of labor and expense required for maintenance. The retention water method also has the drawbacks of large pressure loss, necessitating ancillary equipment such as water treatment equipment, and increasing equipment costs. The inertial collision type oil mist collection device has a small pressure loss, does not require ancillary equipment such as water treatment equipment, and requires compact equipment, which is industrially advantageous. However, this inertial collision type collection device has a problem in that the collection efficiency is lower than that of the filtration type, although this differs depending on the properties such as the viscosity and particle size distribution of the oil mist. In particular, when there is a large amount of fine 1000 lumen mist, the collection efficiency tends to decrease.

The purpose of the present invention is that the pressure loss is small and ancillary equipment such as water treatment equipment is not required, so the advantage is that it can be completed with compact equipment! It is an object of the present invention to provide an oil mist collecting method using a direct impingement method, which is capable of efficiently collecting oil mist of minute particle size, and has high collection efficiency.

The oil mist collection method of the present invention includes installing a plurality of oil mist collection devices (penetration type) in series in the gas flow direction in the flow path of gas containing oil mist, and installing the oil mist collection devices on the upstream side. The wind speed passing through the waste in the collecting device is made smaller than that of the downstream collecting device, and the upstream collecting device collides with the fine oil mist mainly caught in the waste to create a small mist. in the downstream collection device,
Let's collect this growing oil mist! This is what happened.

In other words, the conventional inertial collision type oil mist collection device
Since the purpose is to collect the oil mist as it collides, the gas passing wind speed is set at 1 to 3 m/sec, making it impossible to collect even minute oil mist. In the oil mist collecting method of the present invention, the gas passing wind speed of the upstream collecting device is increased. Therefore, due to the principle of inertial collision, fine oil mist that cannot collide with the passing wind speed of conventional collection devices will collide, and the fine oil mist will also grow into large particles and be captured downstream. This allows them to be easily collected by a collection device.

Examples will be described below.

FIG. 1 is a system diagram according to an embodiment of the present invention, which is applied to collecting oil mist generated from a steel plate rolling mill.

In the figure, reference numeral 10 denotes a rolling mill, which rolls a rolled material 12. During rolling, rolling oil and cooling oil scatter as oil mist from this rolling mill 10.

In this embodiment, this is collected in the following manner. That is, a mill hood 14 is installed above the rolling mill 10. This mill hood 14 is connected to a stack 18 by an exhaust duct 16, and on the way there is an upstream collection device t20, a downstream collection device 22, and an exhaust fan 2.
4 are installed in series one after another. Collection device 20.22
Both are of the inertial collision type, and are configured such that the gas passing wind speed in the upstream collecting device 20 is higher than the gas passing wind speed in the downstream collecting device 22. In the figure, 26.28 is the measurement point for measuring the oil mist concentration in the gas.

FIG. 2 is a partially cutaway side view showing the configuration of the upstream collection device 20. FIG. 30 is a casing, inside which two wire mesh elements 32 are arranged facing each other in a V shape.
2, the rectifying plate 34 is set at V.
They are installed in multiple stages inside the campus. In FIG. 2, 36 is a reinforcing plate for reinforcing the current plate 34, 38 is a pressure-sensitive pipe, and 40 is a measurement port. Gas is introduced from the upper side in the figure, passes through the wire mesh element 32, and then exhausted from the lower side in the figure.

FIG. 3 is a side view of the downstream collection device 22, in which six wire mesh elements 44 are arranged in the casing 42.
They are arranged in a meandering manner to form an inverted V-shape. 46 is a rectifying wall.

Gas is introduced from the bottom in the figure, passes through the element 44, and then exhausted from the top in the figure.

In the processing system configured as described above, gas (air) containing oil mist scattered from the rolling mill 10 is collected in the mill hood 14, passes through the duct 16, and is first introduced into the upstream collection device 20. be done. Since the wind speed in the upstream collecting device 20 is high, fine mist also collides with each other and grows into large oil particles. Some of the mist is still collected by this downstream collecting device. Next, the gas containing oil mist is introduced into the downstream collecting device 22, and after almost all the oil mist is collected, the gas containing the oil mist is transferred to the stack 18.
Air is sent to.

In the present invention, a plurality of oil mist collecting devices are installed, but even if the number of installed oil mist collecting devices is about 2, the oil mist can be sufficiently collected, and the increase in ventilation pressure loss is also small. In addition, when installing two collection devices in this way, the gas flow velocity in the upstream collection device should be 5 to 15 m/see, and the gas flow velocity in the downstream collection device should be about 1 to b. Hereinafter, a measurement example will be explained.

Measurement Example 1 In Figures 1 to 3, rolling oil used for cooling the rolling rolls of a steel plate rolling mill and as a roll coolant for the lubricating piece between the rolls and the steel plate becomes oil mist during rolling. When gas containing oil mist is generated,
The device of the present invention was applied. However, the rolled material is an aluminum steel plate, and the rolling oil is 100% mineral oil.The element 32 of the upstream collection device is made of 36 layers of Nilatated stainless steel wire with 0.25 inch diameter. The element 32 was installed so that the average gas passing velocity in the direction perpendicular to it was 10 m/sec.

In addition, for element 4-1 of the downstream fruit thinning device, 36 pieces of stainless steel wire used on the upstream side and glass yarn made by twisting 3 bundles of 100 pieces with a diameter of about 11μ are machine kneaded. The element is used in layers, and the average gas passing velocity in the direction perpendicular to this element is l m/se.
It was set up so that it was c.

Therefore, the oil mist collection efficiency was measured at two locations, the inlet measurement point 26 and the outlet measurement point 28 in Fig. 1, and when the conventional method was adopted (when only the downstream collection device #22 was installed). ) was compared. The measurement analysis is based on JIS'
Performed according to Z8808. The binding is shown in Table 1.

As shown in Table 1, the collection efficiency of the conventional method was 85.2%, whereas the method of the present invention had a collection efficiency of 95.8%, which was as high as the collection efficiency of the filtration method. Regarding pressure loss, compared to 50 m+oAg in the conventional method, the method of the present invention has a pressure loss of 60 m+oAg.
mAg and showed good results with problematic pressure drop.

Measurement example 2 The rolled material is Ss4tm plate, and the rolling oil is Solipul oil 3.
The method of the present invention and the conventional method were compared in the same manner as in Measurement Example 1, except that the concentration was changed to 1, and the results are shown in Table 2.

From Table 2, Section 2, it is clear that the collection efficiency of the method of the present invention is as high as 90.3%, compared to the collection efficiency of the conventional method of 84.9%, and that there is almost no problem with pressure loss. .

According to Measurement Example 1 & Regular Example 2, the amount of oil mist generated and the particle size distribution differ depending on the rolling oil and rolling material, so although there is a difference in collection efficiency, according to the method of the present invention, It has been demonstrated that high performance can be obtained compared to conventional methods.

In addition, in this a*+J regular regulation, the oil mist collection device of Bouiyametsu/Yuereme/To was used in the upper side and downstream side collection devices, but the oil mist collection device containing bending steel plate or curved steel plate was used. It's okay. In addition, due to changes in the roughness of oil mist in the gas, by installing a bypass circuit in the upstream collection device and operating it, the pressure loss of the entire device can be reduced and the energy consumption of the exhaust fan can be reduced. It is also possible to measure

As described above, the present invention uses an inertial collision method, has small pressure loss, does not require ancillary equipment such as water treatment equipment, is compact, and can capture oil mist of minute particle size with high collection efficiency. can be collected.

[Brief explanation of the drawing]

Fig. 1 shows a pigeon coop for treating oil mist-containing waste from a rolling mill by the method of the present invention; Fig. 2 is a diagram of the system;
The figure shows the enclosure of the downstream collection device 1310...Rolling mill, 14...Mill foot, 18...Exhaust duct, 20...
...Upstream side extraction mount fry, 22-downstream side collection device. 3rd figure life

Claims (3)

[Claims] (1) A plurality of inertial collision type oil mist collection devices are installed in series in the flow direction of the gas to be processed in the passage of the gas to be treated containing oil mist, and the oil mist collection device on the upstream side An oil mist collection method characterized by making the gas passing wind speed higher than the gas passing wind speed in a downstream oil mist collecting device. (2) The oil mist collection method according to claim 1, characterized in that two oil mist collection devices are installed. (3) The gas passing wind speed in the upstream oil mist collecting device is 5 to 15 m/sec, and the gas passing wind speed in the upstream oil mist collecting device is 1 to 3 m/sec.
/3e(, The oil mist collection method according to claim 2, characterized in that: