JPS6121682B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a mechanical seal protection device suitable for a mechanical seal used, for example, in a horizontal centrifugal thin film evaporator.

[Background of the invention]

FIG. 1 shows a horizontal centrifugal thin film evaporator with a liquid inlet 5 attached to a heating cylinder 1 provided with a jacket 2.
The liquid supplied from the tank is pressed against the inner surface of the heating cylinder 1 by the stirring blades 3 fixed to the rotating shaft 4, forming a thin film, heated by the heating medium supplied into the jacket 2, and a part of the liquid is evaporated. The evaporated matter is discharged through the outlet 6 and the liquid is discharged through the liquid outlet 7. At the portion where the rotating shaft 4 passes through the isolation plates 8 and 9, the fixed ring 10 of the mechanical seal passes through the isolation plates 8 and 9 as shown in FIG.
The rotating ring 11 is sealed with a packing 13 attached to the rotating shaft 4, and the rotating ring 11 of the fixed ring 10 is sealed with a packing 14 attached to the rotating shaft 4.
It is sealed at the sliding surface with 1. When the above-mentioned operation is performed, liquid may adhere to the mechanical seals attached to the isolation plates 8 and 9 due to entrainment of droplets or the like. In particular, if the liquid is easily solidified, it will solidify on the seals 13 and 14 of the mechanical seal or on the sliding surface, causing damage to the mechanical seal or leakage, making stable operation impossible. There is a problem.

[Purpose of the invention]

An object of the present invention is to prevent liquid from adhering to a mechanical seal, thereby preventing leakage or damage to the mechanical seal due to adhesion of liquid, thereby enabling stable operation.

[Summary of the invention]

The present invention protects the mechanical seal by providing a compartment between the inside of the can and the mechanical seal so that the liquid inside the can does not come into direct contact with the mechanical seal.

[Embodiments of the invention]

Liquid may flow into the mechanical seal part during operation, or in the case of batch operation, it may occur during cleaning after completion of operation. For example, at the end of a run, some liquid (eg, polymer liquid) remains in the can. When this is filled with solvent etc. and cleaned,
The solution that dissolves the residual liquid comes into contact with the mechanical seal, but even if the cleaning solvent is extracted, the solvent in the liquid that has adhered to the mechanical seal may evaporate and the polymer may remain attached.

Therefore, as shown in FIG. 3, the present invention does not attach a mechanical seal to the center of the isolation plates 8 and 9
A compartment 15 is provided outside the isolation plates 8 and 9, and a mechanical seal consisting of a fixed ring 10, a rotating ring 11, etc. is attached to the outside of the can in the compartment 15, and the liquid inside the can or the cleaning liquid inside the can comes into direct contact with the mechanical seal. Try to prevent it from happening. 12 is a shaft seal housing, 16 is a cleaning liquid inlet, and 17 is a drain outlet.

Therefore, even if liquid leaks into the compartment 15 from the part where the rotating shaft 4 penetrates the isolation plates 8 and 9 during operation,
Since the drain is extracted from the drain outlet 17 at the bottom of the compartment 15, contact with the mechanical seal is prevented. In addition, when cleaning the inside of the can by batch operation, etc., fresh cleaning liquid can be introduced from the cleaning liquid inlet 16 provided in the compartment 15 and drawn out from the drain outlet 17, so that the cleaning liquid inside the can can reach the mechanical seal. Contact can be prevented. Further, it is even more effective if a liquid drainer 18 is provided.

〔Effect of the invention〕

According to the present invention, the mechanical seal can be prevented from leaking or being damaged, and the device can be operated stably for a long period of time.

Especially when concentrating a polymer solution dissolved in a low-boiling point solvent, a polymer solution that tends to gel, or when it is extremely difficult for the mechanical seal lubricant to flow into the can, it is possible to drain the liquid leaking from the compartment. Therefore, it is extremely effective.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing a horizontal centrifugal thin film evaporator;
FIG. 2 is a sectional view showing a conventional device, and FIG. 3 is a sectional view of a mechanical seal protection device showing an embodiment of the present invention. 4... Rotating shaft, 8, 9... Separation plate, 10... Fixed ring, 11... Rotating ring, 13, 14... Packing, 15... Compartment, 18... Liquid drainer.

Claims (1)

[Claims] 1. A compartment is provided outside the partition plates at both ends of the heating cylinder through which the rotating shaft of the horizontal stirring device passes, a mechanical seal is attached to the outside of the can in the compartment, and a cleaning liquid inlet and a drain outlet are provided in the compartment. A mechanical seal protection device for horizontal stirring equipment.