Comparison of various packing's on the basis of their materials using two different solute gases, CO2 and O2, is being presented. Calculations were done on the liquid side and height of transfer units as well as number of transfer units obtained for various flow rates. The result shows superiority of steel Raschig rings over ceramic, glass and plastic rings. Results were analyzed considering material properties such as wettability, surface area offered per square inch, packing factor and voidage. The operating conditions were Temperature = 25°C and Pressure = 1atm. The values of effective interfacial area offered by Raschig rings of different materials vary to some extent. Steel rings hold sway over ceramic rings but the difference is not much. Glass rings and plastic rings come third and fourth respectively and are way behind in perform- mince. The high density of ceramic Ranching rings and steel rings provides each ring with high me- chemical strength and can thus be stacked in larger quantities within your column to further boost the required process. In Ranching rings ceramic is a bet- term option than plastic or metals due to high tolerance levels against high heat and strong acids.

Results of removal of dyes from textile waste water using adsorption by activated carbon of rice husk are being presented. This research work is based on case study of waste water treatment plant of koh-e-noor textile industry located in Pakistan. Dyes used in research were Congo red and Magenta. Two parameters (agitation time and adsorbent dose) were selected to investigate the % age removal of dyes. Both of the dyes selected are hygienic, cause skin irritation and allergic dermatitis. It was found that the %age removal of both dyes increased as agitation time and adsorbent dose increased. The %age removal of Congo red was 88% and magenta was 85% by different agitation time, while in case of different adsorbent dose, the % age removal of Congo-red was 69.3% and magenta was 95.3%. It was observed that both of these dyes can be removed by activated carbon of rice husk. These results showed that adsorption by activated carbon of rice husk is a good economical method for the removal of dyes.