In a stirred vessel of 380 mm ID and 530 mm level,the respective advantages of surface aeration and sparger aeration were combined felicitously.

It is found that the defects of single-impeller configurations are alleviated and the dual-impeller configuration consisting of upper Rushton impeller for surface aeration and lower upward-pumpi.

The method of measuring oxygen transition rate Kla and Q s in surface aeration of kraft pulp bleaching effluent and some measured results are described.

The effect of superficial gas velocity and static water height on the wavelet power spectrum is dis- cussed and the vibration mechanism of the tube is analyzed.

Liquid phase oxygen mass transfer coefficient (kLα) was measured in the range of superficial gas velocity (Ug=0.

Presents the operating process of non-heating regeneration drier, analyzes reasons for high instrument air dew point, and proposes corresponding solutions.

Through the experiment to the in-situ production environment, the reasons for pressure fluctuation of instrument air drying system was found out, and effective preventive solutions were proposed.

Measures to reduce surface bubbles of concrete;

How to prevent and cure on the surface bubble of commodity concrete;

Production and prevention of the surface bubble of the concrete;