Simulation Coupled Preliminary Scale Up and Equipment Capacity Assessment of Corncob Based Lactic Acid Production

Abstract

The translation of lignocellulosic lactic acid processes from simulation to industrial development requires a consistent link between process flow rates, residence times and equipment capacity. This study presents a simulation coupled preliminary scale-up and equipment capacity assessment for an integrated corncob to lactic acid process comprising dilute acid pretreatment, enzymatic hydrolysis, fermentation, membrane filtration, acidification, purification and product storage. Reconciled steady state process outputs at a reference corncob throughput of 2,500 kg h⁻¹ were linked to residence time, working volume, membrane flux, tray spacing and storage duration relationships. An 80% vessel working-volume fraction and a 15% membrane-area allowance were applied. The calculated total requirements were 11.35 m³ for pretreatment, 1,096.9 m³ for enzymatic hydrolysis, 23.49 m³ for fermentation, 169.34 m² of membrane area, 15.43 m³ for acidification, a 13.20 m preliminary purification-column height and 49.26 m³ of product storage. Nominal capacities of 12, 1,100, 25 and 20 m³ were selected for the four process vessels, together with 170 m² membrane area, a 14 m column and a 50 m³ storage tank. Hydrolysis accounted for approximately 95.6% of the calculated working volume of the residence time-controlled process vessels because of its 61-h residence time, identifying it as the principal volumetric bottleneck. The purification reboilers required 1,164 kW and represented 43.5% of the total 2,678 kW heating demand, identifying purification as the main thermal bottleneck. The estimates define process-scale capacity requirements and support pilot planning; they are not final mechanical specifications. Mixing, rheology, heat-transfer area, vessel internals, pressure design and vendor verification remain necessary before commercial implementation.