共查询到19条相似文献,搜索用时 281 毫秒
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为了评估陈化纯淀粉掺入陈化粮生产燃料乙醇的应用效果,通过摇瓶试验,以陈化水稻、陈小麦和淀粉为原料,研究酸性蛋白酶和接种量对于高浓度乙醇发酵的影响。结果显示,以陈化水稻和陈化小麦为基础培养基,添加一定比例的淀粉有利于酒精度的提高,当添加量为40%~50%时,酒精度达到最高(13.4%vol~13.6%vol),总糖消耗较为彻底;采用高浓度淀粉醪液(总糖270 g/L左右)和酸性蛋白酶发酵可以有效提高发酵强度,尤其将接种量提升至40%左右时,最高酒精度可达15.1%vol,出酒率达52%以上。采用50 L发酵工艺验证,发现发酵指标与摇瓶一致,DDGS产品蛋白指标较佳。此研究结果表明将高浓度的淀粉以一定比例掺入到混合陈化粮醪液发酵是可行的,具有较强的工业化应用参考价值。 相似文献
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同步糖化浓醪发酵影响因素的探析 总被引:1,自引:0,他引:1
目前发酵法生产燃料乙醇普遍存在着成本较高,耗能过大的问题,解决这些问题已成为今后发酵法生产技术的发展方向。高浓度酒精发酵为生产企业提高经济效益,节约能源,保护环境起到积极的促进作用,在浓醪发酵工艺基础上,采取同步糖化工艺措施能够进一步降低原料消耗及综合能耗,符合燃料乙醇生产技术发展方向,具有重要的推广价值。充分探讨同步糖化发酵过程的影响因素,在工业装置上摸索出同步糖化浓醪发酵过程的控制手段,在传统发酵酒精浓度12%vol的基础上,发酵酒精浓度增加到14%vol。 相似文献
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“酒精沼气双发酵耦联工艺”中硫化物对酒精发酵的影响 总被引:1,自引:0,他引:1
"酒精沼气双发酵耦联工艺"中硫化物会对酒精发酵产生抑制,不利于工艺的稳定运行。与对照相比,pH 4.0,24 mmol/L的硫化物使酒精发酵时间从48 h延长至318 h,酒精产量由90.73 g/L下降至82.28 g/L,酵母数量由3.78×108/mL下降至2.20×108/mL,甘油产量由6.99 g/L上升至11.02 g/L。甘油产量上升是硫化物存在时酒精产量下降的原因之一。硫化物对酒精发酵的抑制性随添加时间的推迟而减弱,这是因为在酒精发酵过程中,硫化物会以H2S的形式随着CO2一起从发酵液逸出。pH 4.0时,硫化物对酒精发酵的临界抑制浓度为1.2 mmol/L。 相似文献
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为优化超期储存小麦和水稻混合发酵生产燃料乙醇的辅料,以发利耐高温酒用干酵母为发酵菌株,采用同步糖化发酵法,研究了小麦添加比例、淀粉酶种类、降黏酶种类及添加方式对于混合发酵的影响。通过测定液化和发酵醪液的相关指标,优化出适合小麦混合发酵的辅料。结果显示,当干物质含量为30%,超期储存小麦添加比例30%,液化阶段使用超强复配淀粉酶(0.26 kg/t粮),同步糖化发酵阶段使用糖化酶(0.68 kg/t粮)、酸性蛋白酶(0.035 kg/t粮),在32 ℃下发酵72 h酒精度可达12.37%vol;在拌料阶段添加蔚蓝木聚糖酶(0.3 kg/t粮),可使蒸馏残液滤速由4.8 mL/min提高至7.8 mL/min,清液干物由8.2%降低至5.7%,可有效减轻后期污水处理压力。 相似文献
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该文以脱壳超储稻谷(全糙米)为原料,开展了半连续浓醪发酵生产燃料乙醇工艺研究。在中粮安徽30万t/年半连续燃料乙醇装置上进行了高浓拌料、喷射液化、同步糖化半连续发酵、精馏后制备乙醇等一系列试验。结果表明,全糙米发酵成熟醪平均酒份达到15.36%vol、平均还原糖含量0.21%、残淀粉含量0.40%、残糊精含量0.55%、酸度8.43 °T、挥发酸含量0.35 g/L。该技术在国内处于领先水平,可为企业带来经济效益,值得进一步推广应用。 相似文献
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In order to establish an efficient bioethanol production system from rice straw, a new strategy to ferment the mixture of glucose and xylose by a sequential application of Saccharomyces cerevisiae and Pichia stipitis was developed, in which heat inactivation of S. cerevisiae cells before addition of P. stipitis was employed. The results showed that heating at 50°C for 6h was sufficient to give high xylose fermentation efficiency. By application of the inactivation process, 85% of the theoretical yield was achieved in the fermentation of the synthetic medium. At the same time, the xylitol production was reduced by 42.4% of the control process. In the simultaneous saccharification and fermentation of the lime-pretreated and CO(2)-neutralized rice straw, the inactivation of S. cerevisiae cells enabled the full conversion of glucose and xylose within 80 h. Finally, 21.1g/l of ethanol was produced from 10% (w/w) of pretreated rice straw and the ethanol yield of rice straw reached 72.5% of the theoretical yield. This process is expected to be useful for the ethanol production from lignocellulosic materials in the regions where large-scale application of recombinant microorganisms was restricted. 相似文献
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为获得高效产乙醇的基因重组菌,该研究从克雷伯氏菌(Klebsiella sp.)WL1316中克隆乙醛脱氢酶aldh基因,进行同源过表达,考察其利用木质纤维素水解液中葡萄糖和木糖的能力,并以乙醇含量为响应值,通过单因素试验及响应面试验对其发酵稻草水解液产乙醇的工艺条件进行优化。结果表明,成功构建了同源过表达aldh基因的重组菌株aldh-pET-28a-Klebsiella sp. WL1316,其保持了野生菌株Klebsiella sp. WL1316利用木质纤维素水解液中葡萄糖和木糖的特性,且发酵稻草水解液产乙醇的最优发酵工艺为发酵时间60 h,异丙基硫代半乳糖苷(IPTG)诱导浓度1.5 mmol/L,发酵培养基初始pH值7.3,初始还原糖含量59 g/L。在此最优工艺条件下,重组菌株的乙醇含量为(5.39±0.51)g/L,是野生菌株[(3.67±0.32)g/L]的1.47倍,表明aldh基因的过表达促进了乙醇产量的提高。 相似文献
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Armando Burgos‐Hernndez Ralph L Price Karen Jorgensen‐Kornman Rebeca Lpez‐García Henry Njapau Douglas L Park 《Journal of the science of food and agriculture》2002,82(5):546-552
The decontamination of aflatoxin B1(AFB1)‐contaminated corn, which is required if the corn is to be suitable for alternative use, by an ammoniation–fermentation integrated process was studied. This process could be used for the production of fuel ethanol from aflatoxin‐containing corn. Different concentrations (0.25, 0.50, 1.00, 1.5 and 2.0% w/w) of ammonium persulphate were tested in the detoxification of AFB1‐contaminated corn during fermentation. In order to increase the decontamination of corn, 0.5 and 1.0% (w/w) azodicarbonamide, benzoyl peroxide and hydrogen peroxide were tested. Peroxides were added at three different stages of the fermentation process: liquefaction, saccharification and fermentation. Levels of AFB1 and ethanol were determined after each fermentation process. Treated corn was tested for mutagenic potential using the Ames test with TA100 tester strain and pure AFB1 as positive control. Addition of 2.0% (w/w) ammonium persulphate caused the highest level of decontamination without affecting ethanol production. Addition of peroxides did not significantly (P < 0.05) increase ethanol production or significantly (P < 0.05) improve the decontamination process. The best processes for decontamination of corn and for ethanol production included the addition of 2.0% (w/w) ammonium persulphate for both and of 1.0 and 0.5% (w/w) benzoyl peroxide respectively. All treated corn samples showed no mutagenic potential. Possible industrial use of these processes is discussed. © 2002 Society of Chemical Industry 相似文献