【正文】 ＝， ， =3200，=4，=0， 將已知值代入得 因?yàn)椋糩Q]=30KN，所以選用的耳式支座滿足要求。推進(jìn)式攪拌器的主要運(yùn)用范圍是攪拌及混合絕對(duì)粘度小于36000厘泊的各種流動(dòng)性的液體，以及制成乳濁液或懸浮液。由前四章的相關(guān)設(shè)計(jì)得知反應(yīng)釜凈直徑Di=1200mm，凈高H=1440mm；工作溫度：100℃；工作壓力：。但是考慮到實(shí)際生產(chǎn)中容器底部會(huì)出現(xiàn)一定量的沉積物，C值不能太?。?C值太大攪拌效果不足，結(jié)合實(shí)際取C=200mm攪拌器浸入攪拌容器液面下的深度（S），攪拌器浸入液體內(nèi)的最佳深度為：[2] S= 對(duì)于雙層攪拌器，攪拌器層間距（Sp）~2范圍內(nèi)，由攪拌槳的軸向作用范圍和反應(yīng)釜的高度決定攪拌槳層數(shù)。它承受的是以扭轉(zhuǎn)為主的扭—彎聯(lián)合作用。考慮到攪拌軸與聯(lián)軸器配合，＝30可能需要進(jìn)一步調(diào)整。根據(jù)電機(jī)的功率＝攪拌軸轉(zhuǎn)速＝200，由文獻(xiàn) 1652頁(yè)表16128選用的電機(jī)型號(hào)為：Y112M4kw電動(dòng)機(jī)。結(jié)構(gòu)如圖6—2所示。 Wheat bran。 Pellets。Hoq et al., 1994). However, the wheat bran particles suspended in the cultivation medium have tobe deposed to soluble pounds to be used by the fungus. The aim of the presented project was to investigate the interaction between the mold and the wheat bran and the deposition of the wheat bran by the enzymes produced by the fungus in stirred tank and airlift tower loop reactors at various operating conditions. and methods Strain, preculture and main cultures Aspergillus awamori CBS was used forthe investigations. The strain was maintained at 4176。C for 7 isolated spores from stock cultures were used. BioreactorsShake ?asks, a 2l bioreactor with working volume (Biostat M Braun Diessel International Melsungen), a 30l Bioreactor with 20 lworking volume (Biostat B20, Braun Diessel International,Melsungen) and a 100l airlift tower loop (ATL)reactor with 65 l working volume (TCI, University of Hannover) were used for cultivations. For description of the reactors and their operation (Siedenberg et al., 1997b).. Process monitoring The online and offline analyses for the process monitoring were described already in Siedenberg et al. (1997b). In addition to these methods。 Weizenkleie, 1995). The fungus used these sole energy and carbon sources for growth by deposing them with particular enzymes. During the deposition of the wheat bran no cellulase and pectinase activitiy, but only hamylase and xylanase could be detected. On account of the presence of the solid wheat bran and because of the adherence of the fungus to the wheat bran as well as by the inclusion of the fungus by the wheat bran (Adolph et al., 1996), it was not possible to determine the fungal cell mass concentration in the culture. However, because of the close relationship between the growth rate and the CO2 production rate (CPR), the cell mass can be estimated by the integration of the CPR over the time. According to the transmission electonmicro scopic investigations, the fungus grew inside the bran. It used the mechanical damage of the bran to evade it. In particular, the layer between the inner and the outer pericarp was colonized. After the dissolution of the pectincontaining structures and the penetration into this space, the fungus ?lled the wheat bran with dense et al. (1996) have shown, that inside of large pellets and clumps no mRNA could be observed. Thus no protein synthesis occurred. It is somewhat unexpected, that the cells in the dense mycelium inside the wheat bran shell still wereprovided with suf?cient oxygen and nutrient to produce xylanase. Before the xylanase appeared in the medium, it could be already detected within the cytoplasma and at the plasma membrane by immunogold assay. After 50 h the xylanase appeared on the surface of the wheat bran fragments and at the wheat branhyphaeinterface as well (Adolph et al., 1996). The concentrations of orthophosphate and ammonium, originating partly from the nutrient salt and partly from the wheat bran, were consumedduring the ?rst 60 h and than increased again, as the older hyphae started to starve and lyse Their ?nal concentrations surpassed their starting concentrations in the nutrient medium.The difference of their ?nal and original concen trations is a measure for their share originating from the wheat bran.. In?uence of the preculture The preculture was prepared with spores in the plex medium containing wheat bran as sole carbon source. The spores needed for their germination the carbon source from the wheat bran. For this purpose they adhered to the surface of the wheat bran and developed within 24 h to hyphae. The largest part of the fungal cell mass formed pellets and were bound to the wheat bran. The duration of the germination and the penetration of the hyphae into the wheat bran as well as the fungal morphology were independent of the spore concentration.. In?uence of the stirrer speed The investigations were carried out under standard operation conditions, except the stirrerspeed, which was maintained at 300, 500 and 750rpm, respectively. By changing the stirrer speed the morphology did not change: pellets were formed, which were surrounded by the wheat bran. Only at late cultivation time (after 100 h), when the wheat bran partly deposed (the aleuron layer was separated from the stoma and disintegrated) and the fungus hyphae were partlylysed, the effect of the stirrer speed was observable. The attachment of the fungus on the wheat bran surface was reduced at higher stirrer speeds. On account of the suspended aleuron particles, an acceleration of the growth could be expected. However, the shortest time lag, the fastest growth ocurred at the lowest stirrer speed. (Fig. 4A).Neither the ammonium uptake, nor the phosphate uptake was higher at high stirrer speeds, than atlower ones. The sugar uptake was considerably lower at 750 rpm, than at 500 or 300 rpm. (Fig. 4B). The xylanase activity was the highest at 300 rpm,and with increasing stirrer speed, it decreased (Fig4C). The low xylanase activity at high stirrer speed can be explained by the less intimate contact between the fungal mycelium and the wheat bran... Culti6ations in the airlift tower loop reactor，The runs in the airlift tower loop reactor were performed under following conditions: The preculture was incubated at 150 rpm, and 30176。 (B) CPR, reducing sugar concentrationsand xylanase activiti