Kawasaki Steel Corporation

Jfe Mineral Company, Ltd.

Hidetaka Suginobe

Nozomu Tamura

Tatsuya Ozawa

Tetsuro Uchida

Katsuhiko Sato

A process for producing a complex oxide containing the valuable metal and an alkali (earth) metal salt, which comprising co-milling a mixture of the valuable metal oxide and/or a precursor thereof, or a mixture of a substance containing the valuable metal oxide and/or a precursor thereof, with an alkali (earth) metal salt to a particle size of the valuable metal oxide or a substance containing the oxide, of 10 &#x3bc;m or less, and heating the co-milled product to a temperature of at least 200&#xb0; C. so as to induce a solid-phase reaction of the valuable metal oxide with an alkali (earth) metal salt.

Method for producing complex oxide of metal

The pressure in the coking chamber of a coke oven is held at about atmospheric pressure, and the temperatures at the opposite longitudinal ends of the combustion chamber are independently controlled. Fuel gas is supplied to hold the temperature at the opposite longitudinal ends to be at least about 1000.degree. C. separately from a main burner for the combustion chamber, and the pressure in the coking chamber during the first part of coking is kept in a range from 5 mmH.sub.2 O below atmospheric to 10 mmH.sub.2 O above atmospheric pressure. This allows efficient coke production even with low moisture content coking coal, and coal crumbling near the oven doors is not a problem. The process is typically carried out in a coke oven having a pressure control system for each coking chamber including plural piping devices for supplying a pressure fluid and switching valves for selectively applying the pressure fluid to the nozzle in the rising pipe through any selected one of the piping systems. The fluid pressure applied to the nozzle and the pressure in the coking chamber are preferably changed over time based calculated relationships between carbonization time, coking chamber pressure, and fluid pressure applied to the nozzle.

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Chiba, Japan

Hidetaka Suginobe