Method for operating flash vessel

Patent metadata

Field	Value
Publication number	US-9896740-B2
Application number	US-201214370841-A
Country	US
Kind code	B2
Filing date	Dec 27, 2012
Priority date	Jan 13, 2012
Publication date	Feb 20, 2018
Grant date	Feb 20, 2018

Abstract

The present invention is such that, with H 1 being the height from a slurry outlet to a control liquid level, H 2 being the height from the control liquid level to the top of a flash vessel, and being the diameter of the flash vessel, 0.35D≦H 1 ≦0.45D, and 0.75D≦H 2 ≦0.85D, and at least one liquid level sensor detects a slurry liquid surface at a control liquid level; when the liquid level sensor detects a slurry liquid surface which has risen, a slurry discharge valve installed on a slurry discharge pipe derived from the flash vessel is opened; and when the liquid level sensor detects a slurry liquid surface which has fallen, the slurry discharge valve is closed, whereby opening and closing of the valve is appropriately controlled thereby to reduce troubles with a steam discharge pipe, the slurry discharge pipe, and the slurry discharge valve.

First claim

The invention claimed is:

1. A method for operating a flash vessel in a high-pressure acid leaching process, the high-pressure acid leaching process being such that a raw material slurry is leached by using an autoclave under high temperature and high pressure and then a temperature and pressure of a leached slurry is reduced to normal temperature and pressure by using the flash vessel,
comprising H 1 as a height from a slurry outlet to a control liquid level, H 2 as a height from the control liquid level to a top of the flash vessel, and D as a diameter of the flash vessel,
0.35D ≦H 1 ≦0.45D,
0.75D ≦H 2 ≦0.85D,
the slurry outlet being positioned on the side of the flash vessel,
at least one liquid level sensor installed at an equivalent level to the control liquid level detects a slurry liquid surface in a hydrostatic tower having a lower part in fluid communication with a liquid phase space of the flash vessel, and an upper part in fluid communication with a gas phase space of the flash vessel, and
wherein, when the liquid level sensor detects a slurry liquid surface which has risen in the hydrostatic tower, a slurry discharge valve installed on a slurry discharge pipe derived from the flash vessel is opened, meanwhile, when the liquid level sensor detects a slurry liquid surface which has fallen in the hydrostatic tower, the slurry discharge valve is closed.

2. The method for operating a flash vessel according to claim 1 , wherein the above-mentioned raw material slurry is a nickel oxide ore slurry, and a temperature and pressure of a leached slurry obtained by leaching said nickel oxide ore slurry with sulfuric acid is reduced to normal temperature and pressure.

Assignees

• Sumitomo Metal Mining Co

Inventors

• Matsubara Satoshi
• Nakai Osamu
• Kyoda Yoji
• Sakamoto Takashi

Classifications

• C22B23/0415 Primary

  with acids or salt solutions except ammonium salts solutions · CPC title

• C22B3/04

  by leaching (C22B3/18 takes precedence) · CPC title

• B01J4/008

  Feed or outlet control devices · CPC title

• B01J2219/00182

  controlling the level of reactants in the reactor vessel · CPC title

• Y02P10/234

  Cross-Sectional Technologies · mapped topic