JP3223128B2 - Reactor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reactor such as a polymerization machine for exchanging heat on the wall of a container by flowing a heat refrigerant.

[0002]

2. Description of the Related Art Generally, a polymerization machine, a reactor and the like used for a suspension polymerization reaction of vinyl chloride or styrene resin are, as shown in FIG. A plate-shaped head plate is welded to the container body to form a pressure-resistant closed container-shaped container body a having a strength to withstand a polymerization pressure of ³ to 15 kg / cm ^2, an outer jacket b is provided outside the container body, and a coolant such as water is contained therein. The reaction heat generated by polymerization in the container is removed by heat exchange passing through the container body wall by passing through the container to maintain an appropriate reaction temperature. The stirrer c is used to homogenize the reactants and bring about temperature equalization, thereby helping to remove heat of reaction. Since the amount of heat of reaction generated in this polymerization reaction is very large, the removal of this heat is the rate-limiting factor of the reaction and the reaction time is regulated, and the amount of product produced is determined by the heat removal operation. Absent.

On the other hand, increasing the size of a polymerization machine is a problem for improving productivity, but this causes a problem in a heat removal function. That is, with the increase in the size of the polymerization machine, the plate thickness of the container body must be increased as required in terms of strength, and this causes a decrease in the heat transfer coefficient through the wall of the container body. In addition, the cooling area of the container wall per unit capacity decreases due to the increase in size. Together, these go against the increase in heat removal capacity, thus reducing production per unit capacity.

Conventionally, as a heat removing means other than the jacket, there are means such as providing a cooling pipe in the container body, and providing a baffle which also serves as a cooling surface. As another means, there is a means such as providing a reflux cooler outside the container body, or a method of guiding the liquid inside the container to the outside and passing it through the cooler and circulating the liquid inside the container. However, the former has the drawback of exacerbating the problem of polymer adhesion and accumulation in the container, and the latter has the drawback of requiring extra care in operation and increasing the cost.

Accordingly, it is conceivable to employ a heat exchange inner jacket instead of the heat exchange outer jacket. However, in this case, the heat exchange area is reduced by the ratio of the inner diameter of the inner jacket to the inner diameter of the container body as compared with the case of the outer jacket. Then, if the inner jacket has the same form as the outer jacket supported at both ends, and if the pressure of the refrigerant flowing through the annular space outside the inner jacket is low, the inner jacket opposes the differential pressure between the container internal pressure and the refrigerant pressure. Because of the need to provide strength, the inner wall thickness is substantially equal to the original container body wall thickness, and the heat transfer coefficient cannot be improved.

Therefore, the cooling means is not provided in the space inside the container main body or outside the container main body, and for the purpose of increasing the heat removal from the wall of the container main body, FIG.
As shown in FIG. 1, a passage partition wall for the cooling medium is provided in a range extending over the entire length of the straight body 2 of the container body 1 in which the dish-shaped end plates 3 and 4 are integrally welded and connected to the upper and lower parts of the cylindrical straight body 2. The supporting member 5 of the narrow band plate also serving as a spiral is distributed and arranged at a constant pitch so as to be in an upright state with respect to the container body, and the outer end of the supporting member 5 is attached to the inner surface of the container body by welding 6 and attached. By attaching a strip-shaped upholstery plate 7 having a width substantially equal to the arrangement interval of the bodies 5 between the support plates 5, and welding and attaching both side edges to the inner end of the support body 5, An upholstery plate 7 having a smooth inner surface without irregularities is formed at a predetermined interval H corresponding to the height of the support 5 from the inner surface of the container body 1, and a refrigerant flows in through an inlet 9. 7
There is known a reaction apparatus which flows out of an outlet 10 through a helical sealed space formed by a support 5 and an inner surface of a body 2 (see Japanese Patent Publication No. 3-4249).

However, the above publication does not disclose the arrangement intervals of the supports 5, but the arrangement intervals are extremely important factors in terms of the production cost of the reactor and the homogenization and uniform temperature of the reactants. However, if the arrangement interval is not within an appropriate numerical range, there are the following disadvantages. That is, if the arrangement interval is too short, the support 5
Therefore, the number of steps for welding and can making increases. Further, since the enclosed space surrounded by the support 5, the upholstery plate 7, and the body 2 is narrowed, the pressure loss of the refrigerant flowing through the enclosed space is increased. Further, since the heat transfer coefficient is different between the portion where the support 5 is present and the closed space portion, if the number of the supports 5 increases, the inner jacket wall surface (the wall in contact with the upholstery 7 and the reactant of the welded portion thereof) Temperature unevenness easily occurs. On the other hand, if the arrangement interval is too long, it is necessary to increase the thickness of the upholstery plate 7 so as to have a strength to withstand the pressure in the container, and the heat transfer coefficient is deteriorated under a constant refrigerant flow rate. Furthermore, even if the arrangement interval is in the proper numerical range, if the height of the support is not in the proper numerical range at the same time, disadvantages such as a decrease in internal volume and an increase in pressure loss occur.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to provide an excellent heat-removing capability of a vessel wall of a container body without increasing production costs. It is another object of the present invention to provide a reaction apparatus having a reaction product and capable of achieving uniform and uniform temperature of a reaction product.

[0009]

The above-mentioned problems cannot be solved by independently examining the arrangement intervals of the supports and the height of the supports. Therefore, the study is conducted to find some relationship between them. As a result of the superposition, when the height of the support is set to H and the arrangement interval of the supports in the height direction of the container body is set to L, it is assumed that there is a relationship of L = KH (K is a constant), and K is varied. When simulating the performance of the reactor by giving L and H arbitrary values within the expected range,
It has been found that the value of K exhibits excellent performance in a certain range. That is, by setting 2 ≦ L / H ≦ 6, the balance between the number of supports and the height becomes appropriate, so that the number of steps for welding and can-making is relatively small, temperature unevenness on the inner jacket wall hardly occurs, and The sealed space surrounded by the support, the upholstery plate, and the inner surface of the container body has an appropriate size without increasing the thickness of the plate and without reducing the internal volume, and the pressure of the refrigerant flowing through the sealed space. The result is a well-balanced design that keeps losses low.

[0010] The effect of limiting L / H is further enhanced.
In order to make it remarkable, 3 ≦ L / H ≦ 5 is more preferable.
No.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a small-width strip support serving also as a cooling medium passage partition is arranged upright at regular intervals on all or a part of the inner surface of a reaction vessel main body, and its outer end is provided. Is welded to the inner surface of the container body, a strip-shaped upholstery plate having a width substantially equal to the arrangement interval of the supports is bridged between the supports, and both side edges thereof are welded to the inner end of the support, In a reactor equipped with an upholstered plate that does not have unevenness to withstand the pressure inside the container , the cold heat formed on the inner surface of the body of the container body
When the medium passage is horizontal, the height of the support that stands upright on the inner surface of the container body is H, and the spacing between the supports is L,
The reactor, which is a 3 ≦ L / H ≦ 5 and the first invention, in the first invention, the electrolyte in the container inner surface
A second aspect of the present invention is a reactor characterized by being polished .

Regarding the relationship between the spacing L of the supports and the height H of the supports, when H is constant and L is considered as a variable: If L / H is less than 2, the number of supports becomes too large. In addition, the number of manufacturing steps becomes large. Further, the hermetically sealed space surrounded by the support, the upholstery plate, and the inner surface of the container body becomes narrow, and the pressure loss increases. Further, temperature unevenness of the inner jacket wall surface occurs.

On the other hand, when L / H exceeds 6, the arrangement interval of the supports becomes too long, and as described above, the thickness of the upholstery plate 7 becomes excessively large. become worse.

On the other hand, when L is constant and H is considered as a variable: If L / H is less than 2, the height H of the support becomes too high and the inner diameter of the inner jacket becomes small, so that the heat transfer area decreases. However, the loss of heat removal capacity increases, and the internal volume decreases.

On the other hand, if L / H exceeds 6, the height H of the support becomes too low, so that the enclosed space becomes too narrow,
The pressure loss of the refrigerant flowing through the closed space increases.

From the above considerations, it is necessary to limit 2 ≦ L / H ≦ 6.

Further, by performing electropolishing on the inner surface of the container, a smooth sound structure having no deteriorated layer can be obtained, so that the reactants are less likely to adhere and accumulate on the inner surface of the container, and the heat transfer coefficient does not deteriorate.

In order to further enhance the effect of limiting L / H, L / H should be 3 ≦ L / H ≦ 5.
Is desirable.

The inner surface of the container means a surface in contact with a reactant, such as a body, an inner jacket wall, a bottom head, and a ceiling head.

Further, L / H will be described in detail.
FIG. 3 shows that the change in the production cost due to the change in L / H of the reactor of the present invention is 1 when L / H = 4,
The ratio to this is referred to as a sales promotion index (symbol “■”). Similarly, the change in heat removal capacity due to the change in L / H of the reactor of the present invention is defined as 1 when L / H = 4. It is a graph showing the ratio to this as a heat removal capacity index (symbol “O”).

The production cost must be suppressed to 1.6 times or less that of the conventional reactor shown in FIG. 4, which corresponds to that in FIG. 3, the sales promotion index must be 1.3 or less. .

The heat removal performance needs to be at least 1.8 times that of the conventional reactor shown in FIG. 4, which means that in FIG. 3, the heat removal performance index must be 0.84 or more. Equivalent to.

Further, the production cost is desirably 1.5 times or less that of the conventional reactor shown in FIG. 4, and the heat removal capacity is 2.0 times or more that of the conventional reactor shown in FIG. It is desirable that This corresponds to a sales promotion index of 1.1 or less and a heat removal ability index of 0.93 or more.

From these two indices, L / H is 2 to 2.
6, preferably between 3 and 5.

[0025]

Embodiments of the present invention will be described below. FIG.
(A) shows, for example, a cylindrical linear body portion 2 of a reaction vessel as shown in FIG. 4, and as shown in FIG. The ratio (L / H) to the height H of the support 5 standing upright on the inner surface of the container body is 3.4.
It is. In FIG. 1A, 11a, 11b, 11
c and 11d are refrigerant inlets, 12a and 12b, respectively.
Reference numerals 12c and 12d denote refrigerant outlets, respectively.

As shown in FIG. 2, the refrigerant flowing in from each of the inlets makes one round along the inner surface of the body in the horizontal flow path 13a formed by the upholstery, the support, and the inner surface of the body of the container body. Thereafter, the process proceeds to the next flow path 13b, and similarly makes one round of the inside of the flow path 13b along the inner surface of the body, and then proceeds to the next flow path 13c, and similarly follows the inside of the flow path 13c along the inner surface of the body. Go around once.
As described above, the refrigerant that has flowed in from each of the inlets circulates in the three horizontal flow paths along the inner surface of the body, and is then discharged from each of the outlets. According to the present embodiment, as in a conventional reactor,
Since the flow path of the refrigerant is not spiral but horizontal, the formation of the flow path is easy, and the processing of the reactor is simple. Further, since the refrigerant flowing into the vessel wall of the reaction vessel is discharged after making three rounds of a horizontal flow path along the inner surface of the body, a long flow formed in a spiral shape as shown in FIG. The pressure loss of the refrigerant is lower and the heat exchange efficiency is improved as compared with the method of flowing along the road. In addition, the container body of this example was made of stainless steel, and was subjected to electrolytic polishing with a phosphoric acid / sulfuric acid-based electrolytic solution to remove a work-affected layer on the surface and form a smooth surface.

The present invention is mainly applied to a device having an internal volume of 40 m ³ or more because the main object of the present invention is to improve a decrease in the heat transfer capability that occurs when the size of the reactor is increased. However, the present invention is not limited to this. For example, an internal volume smaller than 3 m ³ may be employed.

In the case of a reactor having an internal volume of 50 m ³ , there is an example in which the arrangement interval of the supports is 100 mm and the height of the supports is 25 mm.

Further, the flow path may be formed vertically. The flow path may be provided in the bottom end plate portion or the ceiling end plate portion.

[0030]

Since the present invention is configured as described above, the following effects can be obtained. Support that doubles as a partition wall for cooling medium
The ratio between the spacing L of the holding bodies and the height H of the supporting body is within an appropriate range.
Selected, so that the number of supports is not too large,
Do not lead to a rise in Support, upholstery, and container inner surface
Since the enclosed space surrounded by is not too narrow,
Pressure loss does not increase. Moderate size of enclosed space
, Heat exchange is performed well, and moderate heat transfer
The heat transfer area and the heat transfer area.
It has an improved heat removal function. Moreover, the passage of the cooling medium
Because it is horizontal, it is easy to form a flow path,
There is an effect that processing is easy.

In particular, according to the second aspect of the present invention, the container
Good heat transfer because a smooth healthy structure is obtained on the inner surface
Can be maintained .

[Brief description of the drawings]

FIG. 1 (a) is a side sectional view of a reaction vessel body constituting a reactor of the present invention, and FIG. 1 (b) is a partially enlarged view of FIG. 1 (a).

FIG. 2 is a view showing a flow path along an inner surface of a body of a reaction vessel body of the present invention.

FIG. 3 is a diagram showing a relationship between L / H and a heat removal capacity index and a sales promotion index.

FIG. 4 is a side sectional view of a conventional reaction vessel.

FIG. 5 (a) is a side sectional view of another conventional reaction vessel.
FIG. 5B is a partially enlarged view of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Container main body 2 ... Body part 3, 4 ... Dish-shaped end plate 5 ... Support body 7 ... Upholstery 9, 11a, 11b, 11c, 11d ... Inlet 10, 12, 12a, 12b, 12c, 12d ... Outlet

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B01J 14/00 B01J 19/18 C08F 2/00-2/01

Claims (2)

(57) [Claims] Claims: 1. An entire or partial inner surface of a reaction vessel main body,
A small-width band plate support, which also serves as a cooling medium passage partition, is arranged upright at regular intervals and its outer end is welded to the inner surface of the container body to form a strip having a width substantially equal to the arrangement interval of the support. In a reaction apparatus in which a veneer is suspended between supports and both side edges thereof are welded to the inner end of the support, and a veneer without unevenness to withstand the pressure in the container is provided inside the container,
When the passage of the cooling medium formed on the inner surface of the body is horizontal, the height of the support standing upright on the inner surface of the container body is H, and the interval between the supports is L, 3 ≦ L / H ≦ 5 A reaction device, comprising: 2. The reactor according to claim 1 , wherein the inner surface of the vessel is electropolished.