JPS6014156Y2 - acid cooler - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a cooler for sulfuric acid, nitric acid, phosphoric acid, etc.

An anode corrosion protection method was used in which a shell with a heat exchange chamber inside was connected to the anode side, a cathode rod was inserted into the heat exchange chamber, and a predetermined acidic liquid was supplied into the heat exchange chamber to cool the acidic liquid. In acid coolers, an oxide film is formed on the inner peripheral surface of the shell to prevent the shell from being corroded by the acidic liquid being cooled, but in order to maintain normal anodic corrosion protection, It is necessary to completely electrically insulate the cathode rod from the shell and the baffle plate disposed inside the heat exchange chamber.

There are various types of insulating materials, but they must not only insulate, but also not be corroded by the acidic liquid that is to be cooled.

Therefore, the present invention provides an acid cooler that fully satisfies these requirements.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

This embodiment relates to a shell-and-tube type cooler for cooling hot concentrated sulfuric acid.

1 is a stainless steel shell connected to the anode side,
Partition plates 2 and 3 are provided near both ends of the interior, forming a heat exchange chamber 4 in the center, and a communication chamber 5 is formed between one of the partition plates 2 and one end wall 1a of the shell 1. be.

Further, a partition wall 6 is provided between the other partition plate 3 and the other end wall 1b of the shell 1 to form a cooling water supply chamber 7 and a cooling water discharge chamber 8.

9 is a cooling water supply pipe connected to the cooling water supply chamber 7, 1
0 is a cooling water discharge pipe connected to the cooling water discharge chamber 8, 1
1 is a large number of heat exchange tubes that pass through the heat exchange chamber 4 and connect the cooling water supply chamber 7, the cooling water discharge chamber 8, and the communication chamber 5 with each other; Baffle plates are arranged at appropriate intervals along the direction, 13 is a sulfuric acid supply pipe, and 14 is a sulfuric acid discharge pipe.

15 is Hastelloy C (chemical composition N: 589M017~19t Cr11~14M) inserted into the heat exchange chamber 4 through one end wall 1a and one partition plate 2 of the shell 1.
nQ, 2. The cathode rod 16 is a cylindrical body made of tetrafluoroethylene resin that is fitted onto the cathode rod 15, and has a large number of holes 17.

18 is an annular plate welded to the part of the other partition plate 3 facing the cathode rod; 19 is made of tetrafluoroethylene resin disposed within the annular plate 18 and fixed to the other partition plate 3 with bolts 20. The cap is a cap in which the tip of the cylindrical body 16 is fitted and supported.

Reference numeral 21 denotes a closing plate made of polytetrafluoroethylene resin and fixedly disposed within the tip of the cylindrical body 16.

22 is a stainless steel support cylinder that loosely fits into the cylindrical body 16 and has one end welded to one of the partition plates 2; 23 is a ring-shaped body welded to the other end of the support cylinder 22; and 24 is the ring-shaped body. 23 and the through-hole edge 1c of the one end wall 1a of the shell 1
25 is a seal member holder bolted to the through-hole edge 1c; 26 is a seal member disposed between the ring-shaped body 23 and the cylindrical body 16; 27 is a seal member presser bolted to the ring-shaped body 23, and 28 is an electric wire fastened to the base end of the cathode rod 15 with a bolt and nut.

In the above configuration, hot concentrated sulfuric acid (90 to 98% H2SO4
, 50 to 130° C.) is supplied into the heat exchange chamber 4 through the supply pipe 13, and cooling water is supplied into each tube 11 through the supply pipe 9 and the supply chamber 7.

As a result, the hot concentrated sulfuric acid is cooled by the cooling water, and the cooled concentrated sulfuric acid is conveyed to a predetermined location via the discharge pipe 14.

The cooled fresh water is also discharged through the discharge chamber 8 and the discharge pipe 10.

On the other hand, when a current is passed between the shell 1 and the cathode rod 15, an oxide film is formed on the inner peripheral surface of the shell 1 in the heat exchange chamber 4.
This prevents the shell 1 from being corroded by the hot concentrated sulfuric acid that is being cooled.

As described above, according to the acid cooler of the present invention, the shell is on the anode side, and the cathode rod is used to form an oxide film on the inner peripheral surface of the shell, thereby preventing the shell from being corroded. It is possible.

In addition, since the cathode rod is fitted with a cylinder made of tetrafluoroethylene resin, the cathode rod can be reliably electrically insulated from the shell and baffle plate. The coating can be held stably and the coating will not be partially torn.

Furthermore, since the cylindrical body has a large number of relatively large holes, the acidic liquid can be brought into sufficient contact with the cathode rod, and anodic corrosion protection can be reliably achieved.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which FIG. 1 is a schematic explanatory diagram, FIG. 2 is a longitudinal cross-sectional view of the main part, and FIG. 3 is a cross-sectional view of the main part. 1...Shell, 4...Heat exchanger, 7.
・Cooling water supply chamber, ...Cooling water discharge chamber, 15.
... Cathode rod, 16 ... Cylindrical body, 17 ...
...hole.

Claims (1)

[Scope of utility model registration request] An anode corrosion protection method was used in which a shell with a heat exchange chamber inside was connected to the anode side, a cathode rod was inserted into the heat exchange chamber, and a predetermined acidic liquid was supplied into the heat exchange chamber to cool the acidic liquid. In the acid cooler, a cylindrical body made of tetrafluoroethylene resin was fitted around the cathode rod to electrically insulate the cathode rod from the shell and the baffle plate, and a large number of relatively large holes were formed in the cylindrical body. An acid cooler characterized by: