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The present study deals with slow pyrolysis of sesame oil cake in an isothermally operated 50 mm diameter and 640 mm long semibatch pyrolyser in the temperature range of 673−1173 K. Under isothermal condition, a lumped parameter model has been used to determine the kinetic parameters for degradation of solid reactant and formation of volatile and char. The iso-conversional kinetics applicable for DAEM (distributed activation energy model) processes have also been determined for pyrolysis of sesame oil cake under nonisothermal conditions based on the thermogravimetric analyses data at different heating rates. The activation energies at different conversion almost follow a Gaussian distribution. On the basis of presently determined lumped kinetic parameters and the literature data for secondary pyrolysis kinetics, a mathematical model has been developed. The model can predict the time histories of unreacted solid, char, CO, H 2 , CO 2 , CH 4 and condensable pyro-oil. Simulated predictions have been compared with the experimental results satisfactorily.

Biodiesel from algal oil is widely accepted as a promising alternative to fossil fuels because of its renewability and biodegradability. This work aims to explore the technoeconomic feasibility of biodiesel production through the reactive distillation (RD) route. Initially, the algal oil and biodiesel are modeled on the basis of their major constituents. The thermophysical parameters of all the constituent components are computed using the group contribution method and validated with available experimental data with reasonable accuracy. The sensitivity analysis is performed to identify the process parameters, namely, the algal oil to methanol molar ratio, the reflux ratio, the total number of trays, the number of reactive trays, and the reboiler heat duty. A maximum conversion of 99% is achieved with an algal oil to methanol molar ratio of 1:4, a reflux ratio of 2, a total number of trays of 15, 11 reactive trays, and a reboiler heat duty of 6.4 MJ/min. With this, the proposed RD column produces 65.5 mol % biodiesel at the bottom, which is quiet close to that obtained through other routes. Finally, the performance of the proposed RD column is investigated with reference to a conventional multiunit system (CMS), consisting of a reactor followed by distillation, from an economic, energetic, and environmental perspective in terms of total annual cost (TAC), energy savings, and CO 2 emissions. Simulation results indicate a 52.96% savings in TAC, and 43.31 and 40.11% reductions in energy consumption and CO 2 emissions are achieved using the proposed RD column with reference to the CMS.

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