Efficient mass exchange between liquid and gaseous phases is the key to successfully performing a range of different chemical engineering operations. Prof. M. V. Rane and his student of Department of Mechanical Engineering have developed an efficient contact device to help speed up and improve the processes for which it is used. A low cost compact contacting device developed provides greater surface area of contact between two fluids. It has multiple capabilities of large heat and mass transfer area between air, gas or liquid streams. The device was shown to have no carryover of liquid into the out going streams of gas or air. It did not have any flooding problem as well.

This novel design of the device allows it to be of use to efficiently separate gases from liquid, regenerate liquid desiccants, use in distillation columns, rectification columns, absorption refrigeration systems and other diverse applications in chemical processes industry. It can also be used in combination of appropriate devices in applications such as humidifiers, dehumidifiers and air-conditioning devices.

The contact device consists of a disk mounted on a shaft, a trough to hold the liquid in which the contacting disk is partially submerged. It also has tubes in thermal contact with the liquid in the trough, a hood with a chimney to aid air or gas to move over the contacting disks. The trough has a supply and drain facility for filling and emptying. An objective of the research was to make an contacting device that incorporates surface density as high as 600 m2 mass transfer area /m3 which is far greater and superior to conventional Rauschert Hilflow rings that have a surface density of 210 m2 mass transfer area /m3 (designed for high performance packing).

The device is compact, sturdy and rigid. It has no carryover of liquid i.e, the stream of gas or air that flows out does not have any liquid which is an important feature. The contacting device has been made such that it can operate with pressure drop across it from 30 to 60 Pa. The device has a flow through system with great efficiency. The liquid in the trough can be pumped at will with no limit for the volume. The device can be adapted to be used for liquid or gas applications for heating, cooling, conditioning or changing humidity based on the application it is used for. The system has an advantage of operating with low power consumption as well.

Indian patent application no. 153/MUM/2002 Patent grant no. 203949
Inventors: M V Rane and S V Kota Reddy