Effect of H/D ratio and impeller type on power consumption of agitator in continuous stirred tank reactor for nitrocellulose production from cotton linter and nitric acid

Abstract

Abstract In this study, the effect of height/diameter (H/D) ratio and type of impeller on the power consumption of the agitator in the Continuous Stirred Tank Reactor (CSTR) was analyzed. CSTR in the process of producing nitrocellulose from cotton linters with a production capacity of 10,000 tons/year was used as a case study. In designing a CSTR, power consumption is also considered because it is related to techno-economics. The results show that it is necessary to adjust the amount of impeller related to the H/D ratio value because it can affect the level of liquid in the reactor during the stirring process so that it also affects the reaction conversion. This work shows that with the higher H/D ratio, the greater number of impellers needed and increase the agitator power consumption. For specific applications, the number of impellers (NT) must be increased to meet the minimum power consumption. As the result, this work recommends the optimal H/D ratio for CSTR design is the maximum H/D ratio to get the NT-calculation as close as to the NT-taken while satisfying the minimum power consumption required. The optimal H/D ratio can be different depending on the impeller type and application.