利用餐厨垃圾和废水生产油脂研究

以餐厨垃圾和废水为原料,利用油脂酵母和藻类联合培养生产油脂,结果表明油脂酵母Y1油脂产量可达16.9 g/L,餐厨垃圾和废水混合液中的COD、N和P分别为1500、37.8和3.2mg/L,此联合培养技术可用于生产油脂并去除餐厨垃圾和废水中的N、P和COD。     

叠螺式餐厨废弃物脱水机的设计

脱油后的餐厨废弃物含水率较高,若在干燥前利用机械方式脱除其中的水分,将会有效地降低干燥环节的能耗。通过分析叠螺式脱水机工作机理及在石油污泥脱水中的成功应用,结合餐厨废弃物的物性,论证了将叠螺式脱水机应用于餐厨废弃物脱水的可行性;给出了关键零部件的设计参数,为设计叠螺式餐厨废弃物脱水设备提供参考。     

餐厨垃圾微生物发酵生产蛋白饲料的工艺优化

以餐厨垃圾为原料,采用酵母菌、黑曲霉和枯草芽孢杆菌作为混合发酵菌剂进行固态发酵,结合正交试验,建立并优化了餐厨垃圾转化为生物活性蛋白饲料的工艺条件。结果表明,最佳发酵工艺为以酿酒酵母∶枯草芽孢杆菌∶黑曲霉（1∶1∶2）为混合菌剂,接种量1.0%,尿素添加量1.0%,30 ℃发酵48 h,含水量60%,在此发酵条件下发酵产物中粗蛋白含量提高了58.7%;粗纤维、粗淀粉和粗灰分含量均显示下降;氨基酸总含量增加了1.08倍,其中必需氨基酸含量提高了95.9%;维生素B1、B2的含量也有显著提高;微生物指标均符合国家饲料卫生标准（GB/T 5009.23-2006）。     

公共餐厨垃圾饲料化利用的混合菌发酵工艺

为了实现餐厨垃圾的饲料化利用和有效贮藏,该实验模拟实际生产条件,对公共餐厨垃圾厌氧发酵工艺进行了研究。以混合菌发酵的公共餐厨垃圾样品作为菌种,分为4个处理组:(A)调酸+未灭菌、(B)调酸+灭菌、(C)泡菜水+未灭菌和(D)泡菜水+灭菌,于室温下厌氧发酵14 d,分别测定发酵过程中的有害微生物、pH值、乳酸、水分、脂肪、蛋白质和纤维素含量。结果表明,4组的有害微生物如金黄色葡萄球菌和沙门氏菌均未检出,pH值分别达到3.38、3.38、3.34和3.39,乳酸质量分数分别为1.19%、0.43%、0.90%和0.73%,淀粉、脂肪、蛋白质和纤维素等营养成分则未见显著变化。该实验说明餐厨垃圾发酵后未腐败变质,可延长贮藏时间,其中(A)调酸+未灭菌发酵效果最好。因此,混合菌发酵工艺可以实现公共餐厨垃圾饲料化利用。     

底物浓度对餐厨垃圾厌氧消化的影响

在中温(37℃)及固定接种比[菌泥∶餐厨=2∶1(挥发性固体质量比,VS)]条件下,考察了底物浓度(6%、9%、12%)对餐厨垃圾厌氧消化的影响。结果表明,底物浓度对累积甲烷产量、底物甲烷得率和容积产气率影响不同。随着底物浓度增加,累积甲烷产量逐渐增加,甲烷得率逐渐降低,容积产气率先增大后减小,相应的最大值及底物浓度分别为3 062 m L(总固体12%)、479 m L CH4/g挥发性固体(总固体6%)和730 m L CH4/(L·d)(总固体9%)。厌氧消化结束后,体系固形物去除率为19.24%~20.20%,挥发性固形物去除率为31.08%~32.63%。发酵结束后,消化液化学需氧量(COD)、碱度和氨氮浓度均随着底物浓度增加而增加,最大值分别为2 344 mg/L、7 232 mg Ca CO3/L和1 340 mg/L。采用Modified Gompertz模型对餐厨垃圾厌氧消化过程进行拟合,结果表明,总固体为6%时Mmax和Rmax最高,分别为486 m L/g和60.58 m L/(g·d)。     

混合废塑料和餐厨废油添加甲醇共催化裂解制备生物基烃类的研究

为了将农业生产中的废塑料和餐厨废油更好地进行资源化利用,以农业混合废塑料和餐厨废油为原料,NaY分子筛为催化剂,探究在不同的反应温度下甲醇添加量对混合废塑料和餐厨废油共催化裂解制备生物基烃类的影响。以液体产物产率、可燃气体产量、液体产物酸值、催化剂结焦率为指标,确定了混合废塑料和餐厨废油共催化裂解的最佳反应条件,同时对最佳反应条件下所得液体产物的组成进行了分析,对比了液体产物和生物柴油的理化指标,并对混合废塑料和餐厨废油共裂解反应机制进行了分析。结果表明：添加甲醇总体上有利于提高液体产物产率,降低液体产物的酸值、可燃气体产量和催化剂结焦率;混合废塑料和餐厨废油共催化裂解的最佳反应条件为反应温度440℃、甲醇添加量5%,在此条件下液体产物产率为78.52%,液体产物酸值(KOH)为0.59 mg/g,催化剂结焦率为6.06%;与未添加甲醇相比,添加5%的甲醇后,液体产物的组成成分中芳香烃和烯烃相对含量均降低,而烷烃相对含量显著增加;液体产物(烃类燃油)性能优于生物柴油;在添加5%甲醇条件下,混合废塑料和餐厨废油在NaY分子筛催化剂作用下可能发生协同加氢反应,促进了烷烃的生成。综上,混合废...     

Synergetic degradation of waste oil by constructed bacterial consortium for rapid in-situ reduction of kitchen waste

1. Download : Download high-res image (345KB)
2. Download : Download full-size image

     

Two-phased hyperthermophilic anaerobic co-digestion of waste activated sludge with kitchen garbage

For co-digestion of waste activated sludge with kitchen garbage, hyperthermophilic digester systems that consisted of an acidogenic reactor operated at hyperthermophilic (70 °C) and a methanogenic reactor operated at mesophilic (35 °C), thermophilic (55 °C) or hyperthermophilic (65 °C) conditions in series were studied by comparing with a thermophilic digester system that consisted of thermophilic (55 °C) acidogenic and methanogenic reactors. Laboratory scale reactors were operated continuously fed with a substrate blend composed of concentrated waste activated sludge and artificial kitchen garbage. At the acidogenic reactor, solubilization efficiencies of chemical oxygen demand (COD), carbohydrate and protein at 70 °C were about 39%, 42% and 54%, respectively, and they were higher than those at 55 °C by around 10%. The system of acidogenesis at 70 °C and methanogenesis at 55 °C was stable and well-functioned in terms of treatment performances and low ammonium nitrogen concentrations. Microbial community analysis was conducted using a molecular biological method. The key microbe determined at the hyperthermophilic acidogenesis step was Coprothermobacter sp., which was possibly concerned with the degradation of protein in waste activated sludge. The present study proved that the hyperthermophilic system was advantageous for treating substrate blends containing high concentrations of waste activated sludge.     

利用废弃物原料生产L-乳酸的研究进展

阐述国内外L-乳酸生产的研究进展,着重阐述利用废弃原料发酵乳酸的研究情况。     

Char production using waste fibers from dehairing processes

A pyrolysis process was used to prepare char from the coarse guard hair droppings from cashmere dehairing processes. Three preparation variables were examined in this study, namely the heating rate, holding temperature, and holding time. The morphological evolution from hair to char, char yield, and uptake of methylene blue by the resultant char were investigated. Different morphological structures were observed for the char, including lotus-type, honeycomb-like, solid, bamboo-like, gourd-shaped, hollow and fragment structures. Based on the Box–Benkhen Design, two quadratic models were developed to correlate the preparation variables on two responses of the yield and the uptake value of methylene blue for cashmere guard hair char. From the analysis of variance, the char yield from cashmere guard hair is significantly affected by holding temperature and time. The uptake value of methylene blue is significantly influenced by holding temperature, holding time, and quadratic terms of the heating rate and the holding temperature.     

两步法催化废白土油制备生物柴油的研究

以废白土油为原料,采用酯化和酯交换两步法制备生物柴油。选用硫酸铁作为酯化催化剂,选用氢氧化钠作为酯交换催化剂。利用正交实验优化两步法工艺条件,得到酯化反应中各因素最佳的水平组合为硫酸铁用量4%、醇油摩尔比14∶1、反应温度70℃、反应时间3 h,得到酯交换反应中各因素最佳的水平组合为醇油摩尔比6∶1、氢氧化钠用量1.4%、反应温度70℃、反应时间2.5 h。在最佳的酯化和酯交换工艺条件下,总转酯率达到96.4%,所得的生物柴油主要质量指标与0#柴油接近。     

从肝素生产废弃物中分离纯化硫酸皮肤素

筛选了乙醇、丙醇、丙酮三种有机试剂对肝素生产废弃物进行分级沉淀,对比了添加钠离子浓度对分级沉淀的影响。凝胶成像仪对各沉淀级分的醋酸纤维素薄膜电泳结果进行分析,确定了各级分的黏多糖构成比例,表明丙酮法级分14和15的硫酸皮肤素含量占黏多糖组成比例的100%,随后通过DEAE-650S弱离子交换层析进一步分离,得到了高纯度的硫酸皮肤素,高效凝胶渗透色谱法测定该产品纯度为93.27%。     

由杏仁壳及其他农产品废弃物制备生物纺织纤维

绿色产品是否存在其他价值?能否将废弃物转化为具有额外价值的原材料?来自大学实验室和工业公司的研究者们正尝试采用木屑、杏仁壳或其他农产品废弃物作为原料制备纺织品。Ecolastane项目主要致力于研究可再生产业用纺织纤维的生产。     

家具生产中木质废料的来源、控制与处理

分析了家具制造企业原料输入和废料产生情况,针对家具生产过程木质废料的产生情况和废料形式进行了剖析,结合生产实际提出了家具生产木质废料的控制与处理措施。     

以右旋糖酐发酵废液为原料发酵生产丁二酸

以右旋糖酐发酵废液为原料利用琥珀酸放线杆菌发酵生产丁二酸,在比较不同糖浓度废液对发酵产酸影响的基础上,通过Plackett-Burman试验筛选出对摇瓶发酵产丁二酸的主要影响因素Na H2PO4·2H2O,并用单因素试验确定其最适质量浓度为2.8 g/L。在3 L发酵罐上进行分批发酵和补料分批发酵,以60 g/L初糖质量浓度的右旋糖酐发酵废液为碳源,分批发酵46.8 h产丁二酸40.5 g/L;采用30 g/L葡萄糖为起始发酵培养基的碳源,后续补加浓缩右旋糖酐发酵废液的方式进行补料分批发酵,丁二酸质量浓度达到55.0 g/L,生产强度1 g/(L·h),糖酸转化率为0.83 g/g。结果表明:以右旋糖酐发酵废液为原料发酵生产丁二酸,为解决废液处理排放提供了新途径,具有良好的应用前景。     

废动植物油脂工业化生产生物柴油的研究

以废动植物油脂为原料,在自制DYD催化剂作用下生产生物柴油,详细介绍了生产生物柴油的工艺过程、分析方法、产品质量以及在柴油机上的试验情况,通过正交试验确定了生产生物柴油的最优工艺条件,即醇油摩尔比4∶1,催化剂用量2%,反应温度75℃,反应时间8 h。测试结果表明,所生产的生物柴油各项性能指标都达到美国同类产品的标准(D6751-03a),在动力性、经济性基本不变的情况下,其环保性能指标明显改善,完全能在柴油机上应用。     

开菲尔直投式发酵剂在益生菌干酪生产中的应用研究

该研究主要将开菲尔粒制备成直投式发酵剂应用于干酪的生产。 以FD-DVS R-704商业干酪发酵剂制作的干酪为对照,对其 理化指标、挥发性香气成分、质构特性和感官指标进行测定与评价。 结果表明,与对照干酪相比,开菲尔干酪的水分含量、pH4.6-可溶 性氮（SN）及12%三氯乙酸（TCA）-SN的含量极显著增高（P＜0.01）,pH值极显著低（P＜0.01）,而粗脂肪比例和总游离氨基酸（TFAA） 含量无显著差异（P＞0.05）,不饱和脂肪酸（UFA）含量显著增高（P＜0.05）;醇类和酯类物质的种类增多;硬度和咀嚼性极显著降低（P＜0.01）,胶黏性极显著增大（P＜0.01）,内聚性和弹性无明显差异（P＞0.05）;开菲尔粒益生菌干酪呈乳白色,表面有光泽,不仅具 有干酪特有的滋味和气味,且具有开菲尔发酵乳的特有风味,带有适宜的酒香味。     

Utilizing waste products from the food production and processing industries

Waste in the food industry is characterized by a high ratio of product-specific waste. Not only does this mean that the generation of this waste is unavoidable, but also that the amount and kind of waste produced, which consists primarily of the organic residue of processed raw materials, can scarcely be altered if the quality of the finished product is to remain consistent. The utilization and disposal of product-specific waste is difficult, due to its inadequate biological stability, potentially pathogenic nature, high water content, potential for rapid autoxidation, and high level of enzymatic activity. The diverse types of waste generated by various branches of the food industry can be quantified based on each branches' respective level of production. Moreover; the origins of each type of waste and a tabulated overview of the traditional agricultural methods for reusing the waste are discussed. Additionally, alternative methods of waste management have emerged, which target the most important contents of the waste. In conclusion, new possibilities for the utilization of food industry waste are described.     

Pectic oligosaccharides production from orange peel waste by enzymatic hydrolysis

Orange peel waste (OPW) was evaluated as a raw material for the enzymatic production of pectic oligosaccharides. In a preliminary step, free sugars and other water‐soluble compounds were extracted from OPW to obtain a substrate for enzymatic hydrolysis (EHS), to achieve two objectives: (i) removal of sugars and impurities, and (ii) production of a sugar‐rich stream suitable for further utilisation, according to the ‘biorefinery’ philosophy. EHS was treated with hydrolytic enzymes (pectinases and cellulases), and the effects of selected operational variables (enzyme charges and reaction time) on selected dependent variables (measuring the conversions of polysaccharides into mono‐ and oligosaccharides, and liquor recovery) were assessed. Mathematical models were developed for this purpose. Under selected conditions, the models predicted that 100 kg of EHS yielded 7.5 kg of gluco‐oligosaccharides, 4.5 kg of galacto‐oligosaccharides, 6.3 kg of arabino‐oligosaccharides and 13 kg of oligogalacturonides (contained in 991.6 kg of liquor).