JPS6111101A - Evaporator - Google Patents

Abstract

PURPOSE:To reduce the size of an evaporator and to improve its performance by passing heating steam from a high temp. side heat exchanger to a low temp. side heat exchanger through a reducing valve and flowing the liquid to be treated from the low temp. side heat exchanger to the high temp. side heat exchanger. CONSTITUTION:Feed liquid is supplied from a feeding port 3 to a low temp. side heat exchanger 1 to exchange the heat with the steam at lower temp. and then introduced into the high temp. side heat exchanger 2 through a liquid pipe 3 to exchange the heating steam at higher temp. The steam is discharged from a steam outlet port 4 and the concentrated liquid is discharged from a discharging port 5 of the concentrated liquid. The heating steam is supplied from a steam feeding pipe 6 to the high temp. side heat exchanger 2, and supplied further to the low temp. side heat exchanger 2 through a reducing valve 8. The drain is discharged from a drain discharging port 9.

Description

[Detailed description of the invention] The present invention relates to an evaporator used for distillation, concentration, etc. of liquids.

An example of a conventional evaporator of this kind is shown in FIG.
1) Heating is done by supplying steam into the bottom of the steam jacket (03), but since the heat transfer surface is flat, the scale attached to the heat transfer surface is heated. Although it is easy to remove, there is a problem that it becomes large to increase the heat transfer area.

Another example of a conventional evaporator is shown in Figure 5, where the stock solution taken out from the separator (04) is sent by a pump (o5) to a plate heat exchanger (06), where it is heated by steam. returned into the rear separator (04),
The separated vapor is taken out from the top, and the separated liquid is mixed with the stock solution in the separator (04) and is then taken out again by the pump (05). This uses a plate heat exchanger (o6), which has a large heat transfer area and can be made smaller.However, in order to remove scale attached to the heat transfer surface, a plate heat exchanger (o6 ) had to be disassembled frequently.

The present invention was devised to address the above-mentioned problems, and its purpose is to provide an evaporator that is compact, has high performance, and is easy to clean.

The gist of the present invention is to include a high-temperature side heat exchanger that is easy to clean and a low-temperature side heat exchanger that has good heat exchange performance.
The heating steam is caused to flow from the high-temperature side heat exchanger to the low-temperature side heat exchanger via the pressure reducing valve, and the liquid to be evaporated is caused to flow into the high-temperature side heat exchanger via the low-temperature side heat exchanger. It is located in the evaporator.

Since the present invention has the above-mentioned configuration, the liquid to be evaporated, which is highly concentrated and easily generates scale, is heated by the high-temperature side heat exchanger of an easy-to-clean type, so even if scale occurs, it can be easily removed. This can be removed, and at the same time, the liquid to be evaporated, which has a low concentration, is heated by a low-temperature side heat exchanger with good heat exchange performance, so it can be efficiently heated without causing school. Therefore, the evaporator as a whole becomes smaller, more powerful, and more efficient, and its cleaning becomes easier.

The present invention will be specifically explained below with reference to FIGS. 1 to 3.

FIG. 1 is a schematic system diagram showing the first embodiment of the present invention. In FIG. 1, (21 is an evaporator type high-temperature side heat exchanger that is easy to clean; This is a plate-type low-temperature side heat exchanger.The raw liquid is supplied from the supply port (3) into the low-temperature side heat exchanger (1), where it is heated by exchanging heat with low-temperature heating steam. It enters the high-temperature side heat exchanger (2) through the pipe (3), where it exchanges heat with high-temperature heating steam and evaporates.The steam is taken out from the steam outlet (4), and the concentrated liquid is sent to the concentrated liquid drain. Heating steam is taken out from the outlet (5).Heating steam is supplied from the steam supply pipe (6) into the high-temperature side heat exchanger (2), and after heating the stock solution there, it is The pressure is reduced as it passes through the valve (8), and then it is supplied into the low-temperature heat exchanger (1).By heating the stock solution in the low-temperature heat exchanger (1), it condenses and liquefies itself. It becomes drain and is taken out from the drain outlet (9).

FIG. 2 is a schematic system diagram showing a second embodiment of the present invention. A side heat exchanger 02 is stored.The stock solution is supplied from the supply port a3 into the distribution chamber I, and flows down the outside of each wet wall type low temperature side heat exchanger 02 through the distribution hole (15). It evaporates by exchanging heat with the low-temperature heating steam inside the wall through the wall.The stock solution that falls from the low-temperature side heat exchanger (I) collects in the liquid reservoir of the high-temperature side heat exchanger 0υ, and is transferred to the lower surface of the liquid. It evaporates by exchanging heat with high-temperature heated steam via the hot surface a0.The evaporated steam is taken out from the steam outlet a7), and the highly concentrated concentrated liquid is taken out from the concentrated liquid outlet a.
It is taken out from the mark. On the other hand, high-temperature heating steam is supplied from the steam supply pipe to the high-temperature side heat exchanger (1) (2).
t), where the raw solution is heated and the steam becomes more humid, passes through the steam pipe Qυ, is reduced in pressure by the pressure reducing valve (c), becomes low temperature, and enters the low-temperature side heat exchanger α. Here, it exchanges heat with the stock solution and condenses completely, becoming drain and flowing into the pipe (
It is discharged through c).

Figure 3 shows the changes in temperature of the heating steam and stock solution in the high-temperature side heat exchanger and the low-temperature side heat exchanger. Although the pressure is high, since the pressure is reduced through the pressure reducing valve and then supplied to the low-temperature heat exchanger, the temperature in the low-temperature heat exchanger is considerably lower than that in the high-temperature heat exchanger. On the other hand, the stock solution gradually evaporates in the process of flowing from the low temperature side heat exchanger to the high groove side heat exchanger, and as its concentration increases, its evaporation temperature also gradually increases.

The higher the concentration, the more scale will be generated (although the highly concentrated stock solution is heated in the high-temperature side heat exchanger, and this high-temperature side heat exchanger is used for example By using an evaporator type with a flat heat transfer surface, even if scale adheres to the heat transfer surface, it can be easily removed.On the other hand, the less concentrated stock solution generates less scale, Therefore, this stock solution is heated in a low-temperature side heat exchanger such as a plate type or multi-tube type that is difficult to clean but has good heat exchange performance.

(Thus, the evaporator as a whole becomes smaller, has higher performance, and is easier to clean.

Although the present invention has been described above with reference to embodiments, it goes without saying that the present invention is not limited to such embodiments, and that various design modifications can be made without departing from the spirit of the present invention. .

[Brief explanation of the drawing]

FIG. 1 is a diagrammatic system diagram showing the first embodiment of the present invention;
The figure is a schematic system diagram showing the second embodiment of the present invention, and FIG. 3 is a diagram showing temperature changes of the heating steam and the raw solution in the present invention. FIGS. 4 and 5 are schematic system diagrams showing conventional evaporation devices, respectively. High temperature side heat exchanger...(2), t(1, low temperature side heat exchanger...(1). Sumibe, pressure reducing valve...(8), (22) Sub-agent Patent attorney Okamoto 3 persons outside the kiln (sealing of the procedural amendment) Commissioner of the Japan Patent Office Manabu Shiga1, Indication of the case Patent Application No. 129937 of 19822, Title of the invention Evaporation device3, Person making the amendment Relationship with the case Patent applicant: (620) Mitsubishi Heavy Industries, Ltd. 4, sub-agent: Toranomon Sangyo Building, 2-29 Toranomon-chome, Minato-ku, Tokyo 105 (501) 28095, subject to amendment: Description and drawings 3, amendment Content 1, in the specification (1) "Liquid pipe (3)" in the first line of page 4 is replaced with "liquid pipe (3)"
I will correct it. (2) Add the following between page 6, line 11 and line 12. Note: ``In addition to steam, refrigerant vapor from a vapor compression heat pump or vapor from a self-vapor recompression type evaporator can be used as the heating vapor.'' 2. In the drawings (1) Figure 1 (copy) will be corrected as shown in red on the attached sheet. (2) Correct Figure 2 as shown in the attached sheet. Figure 1 27

Claims (1)

[Claims] Equipped with a high-temperature side heat exchanger that is easy to clean and a low-temperature side heat exchanger that has good heat exchange performance, heating steam flows from the high-temperature side heat exchanger to the low-temperature side heat exchanger via a pressure reducing valve. An evaporation device characterized in that the liquid to be evaporated is caused to flow into the high temperature side heat exchanger via the low temperature side heat exchanger.