CFD modeling of baijiu yeast spray drying process and improved design of drying tower

Abstract

High-quality baijiu yeast – modified Sporidiobolus johnsonii A (MSJA) suffers from the problem of weak vitality, thus failing to combine high efficiency and high survival rate drying. Therefore, in this study, we firstly designed a real-time sampling experiment of MSJA spray drying process, and based on this, we established a New CFD model (N-CFD model) that can accurately simulate the variation of the spray drying process of microorganisms such as MSJA. Then, a new spray drying air inlet mechanism of "high-temperature cyclone in the center L-type guide plate + medium-temperature laminar flow in the peripheral holes and slots" was invented. Finally, the parametric scanning simulation was carried out to optimize the flow angle θ of the L-type guide plate using the N-CFD model. The results show that, firstly, the N-CFD model can accurately simulate the temperature distribution (P₁ = 0.05) and the motion of drying particles in the drying tower. Secondly, the optimized new air inlet mechanism with the L-type guide plate flow angle θ = 47° can even out the temperature and particle distribution in the drying tower, which meets the "two-stage theory of spray drying." Finally, under the premise of ensuring the drying efficiency, the survival rate of MSJA spray drying was increased from 42.6% to 82.24%, which achieved the objectives of low sticking wall, high efficiency and high survival rate of spray drying MSJA.

Keywords:

• High-quality baijiu yeast - modified Sporidiobolus johnsonii A
• spray drying
• CFD modeling analysis
• optimized design of drying tower air inlet

Disclosure statement

The authors declare no conflicts of interest.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [grant number 51876109]; the key R&D Program Project of Shaanxi Provincial [grant number 2021NY-129]; the Key Project of International Science and Technology Cooperation Program for Shaanxi Province [grant number 2020KWZ-015]; and the Scientific research plan project of youth innovation team of Shaanxi Provincial Department of Education [grant number 22JP012]