Multifunctional Solid-state Fermentation Bioreactor With Keeping Bacteria Pure And Its Inoculation Spraying Technology

Solid state fermentation (SSF) technology has a very wide range of applicationson account of the increasingly energy shortage at present, especially on account ofshort fermentation time, low energy cost, high product yield rate and lessenvironmental pollution for SSF. Modern solid-state fermentation equipment shouldalso adapt to this extensive demand. Analyzing the applications and researches of thesolid-state fermentation bioreactor in home and abroad, a multifunctional solid-statefermentation bioreactor with keeping bacteria pure was proposed, which could notonly realize the sterilizing, cooling, inoculation and fermentation, but inspect andcontrol the temperature, humidity, oxygen contents of the materials. A solid-statefermentation bioreactor with pure bacteria and its chain transmission system weredesigned based on the movement of the translational tray mechanism withoutinterference and the space rate of the equipment with the highest utilization. Based onthe theory of fluid dynamics and particles dynamics, the microorganism particles’properties on its motion in the solid-liquid two-phase flow of the experimental nozzleswere analyzed. Energy dissipation rate to quantify the microbial particles’ damagewithin hydrodynamic stresses were analyzed. The numerical simulations of thenozzles were compared with experimental results to evaluate the effects of nozzletype, spraying parameters on the relative viability after flow through each nozzle type.A new type of solid-state fermentation bioreactor with a tray mechanism whichhas a kind of top and bottom turn-covers was designed.The inoculating tube wasarranged into the hermetic bioreactor. After sterilization, the nozzle of the inoculationspraying system can spray the bacterium on the solid substrate, to realize sterilizing,cooling, inoculation and fermentation in one solid-state fermentation bioreactor. Theeffect of process parameters on the fermentation process and the yield rate of productsand the control strategy were analyzed. By the automatic control of the fermentationprocess, it can create a good production conditions, ensure the pure solid-state fermentation indeed and the high quality of products. These also make it easy toenlarge to an industrial scale.Based on the Matlab, the mechanism parameters of the three arrangements withvarious situations were solved preliminarily and precisely based on the movement ofthe tray without interference and the space rate of the equipment with the highestutilization.The solid-liquid two-phase flow of the microorganism particles’ sprayinoculation fluid system was analyzed. Fluid characteristics of the two-phase flowcomposed of microorganisms and sterile water was discussed and the forced state ofthe microorganism particles was also analyzed. The energy component was deducedand discussed and the theoretical basis, reliability and practicability of the energydissipation rate which can quantify the microbial particles’ damage withincomprehensive hydrodynamic stresses were also discussed and analyzed.The effect of nozzle type, spraying parameters on the results of the sprayinginoculation was studied by simulation using FLUENT. A set of spraying inoculationexperimental flow device was designed and manufactured, at the same time, anappropriate test method was determined. A user-defined function was created inFLUENT to compute the energy dissipation rate from the flow field information. Bysetting reasonable boundary conditions and initial conditions, simulations of threetype nozzle’s flow field of the pressure and energy dissipation rate were conducted foreach size of nozzle and the experimental inlet pressure. Experimental and simulationresults showed that it was feasible to use spraying inoculation to realize automationand pure solid state fermentation process and ensure uniformity of the inoculation.The best spraying characteristic parameters can be found to ensure of microbialviability after inoculation. It also can be found that the maximum energy dissipationrate of different type nozzles were different, position where the maximum value atwas also different. Experimental and simulation results showed that the energydissipation rate of the Turbo TeeJet Flat-fan nozzle TT1102at the inlet pressure of0.3MPa was the lowest among the experimental nozzle type and size and the sprayingcharacteristic parameters. The results of experiment and numerical simulation will have certain reference value and directive significance to the biological spraying toavoid hydrodynamic damage to biological agents.