Chiyoda Corporation

Masataka Uemura

Dai Takeda

Noboru Takei

Eiji Awai

Jun Matsumoto

Kazushige Kawamura

Kazuya Kumagai

Hironobu Marukawa

Takao Kameda

Sosuke Kido

The impurity removal method removes impurities in an exhaust gas and includes forming a froth layer in a tank, by blowing the exhaust gas into an absorbing liquid contained in the tank via a gas dispersion pipe, wherein, given that a proportion of the gas occupying the froth layer is defined as a gas holdup, impurities such as soot dust included in a gas such as an exhaust gas is removed efficiently and at a low cost by setting a gas holdup in the froth layer to be 0.4&#x2dc;0.9, setting a height of the froth layer to be 0.2&#x2dc;1.8 m, and setting a gas-liquid contact area per unit volume of the froth layer to be 1500&#x2dc;2500 m/m.

Method of removing impurities

A treatment process of a gas containing zero-valent mercury and a mercury separation system, by which the amount of an iodine compound used can be reduced when the zero-valent mercury is separated from the gas containing the zero-valent mercury by using the iodine compound. The process has a step of oxidizing the zero-valent mercury contained in the gas with a first liquid phase containing an alkali metal iodide, thereby obtaining a second liquid phase containing a divalent mercury ion and an iodide ion; a step of separating the divalent mercury ion as mercury sulfide by adjusting the pH of the second liquid phase; and a step of circulating a third liquid phase which is obtained by separating the mercury sulfide in the mercury separation step to use the third liquid phase as the first liquid phase in the mercury oxidation step.

Treatment process of gas containing zero-valent mercury and mercury separation system

This desulfurization device is for desulfurizing a discharge gas which contains sulfur oxides and which was discharged from a device for sulfuric acid production that includes a concentrated-sulfuric-acid production step in which sulfur trioxide gas obtained by oxidizing sulfur dioxide gas is absorbed in an aqueous sulfuric acid solution while supplying water thereto to thereby produce sulfuric acid having a concentration as high as 90 wt % or more but less than 99 wt %, the desulfurization device comprising: a desulfurization tower in which the sulfur oxides are removed from the discharge gas and, simultaneously therewith, dilute sulfuric acid is formed from the sulfur oxides; and a dilute sulfuric acid mixer which, in the concentrated-sulfuric-acid production step, mixes the dilute sulfuric acid with the aqueous sulfuric acid solution.

Desulfurization method and device for sulfuric acid production device

Growing community of inventors

Yokohama, Japan

Masataka Uemura