盐藻细胞泡载分离法采收的初步研究

通过对盐藻细胞的浓缩倍数和采收率的测定，考察了藻液pH值、气体流速(vg)、藻细胞初始浓度(C0)对盐藻细胞的泡载分离采收性能的影响，优化了盐藻细胞泡载分离采收条件. 结果表明：在vg为60 ml/min，C0为2.58?105 个/ml，pH值为7.5的条件下，盐藻细胞泡载分离的采收率达90%~94%，浓缩倍数达30~34. 泡载分离是分离浓缩盐藻细胞的一种简便、高效的方法.     

微藻细胞的连续泡沫分离法采收

为考察连续泡沫分离法采收微藻细胞的可行性 ,在一种斜臂泡沫分离装置上 ,以螺旋藻为模型藻种 ,较为详细地研究了载气流率、藻液进料流率、浓度、pH值、离子强度、乙醇浓度、进料位置、泡沫段与液相段高度之比等因素对泡载采收性能的影响。结果表明 :在载气流率、藻液进料流率或藻液浓度较低时采收性能良好 ;当 pH值为 11、离子强度为 1 3× 10 ⁴ μs·cm^-1、乙醇浓度为 3%(体积 )时泡载收率可达 2 5 %～ 45 %;采用泡沫相段进料有利于提高泡载采收性能。提出的连续泡载采收动力学模型与实验值拟合较好 .     

溶气式泡载分离器内减压成泡过程

通过对压力饱和溶气水减压成泡过程的热力学分析表明,溶气压力越高,形成气泡越细密,释气较完全。采用Kolmogoroff各向同性湍流理论得出湍流场中气泡稳定存在的条件和气泡大小随操作条件的变化规律。实验考察了操作条件对气泡分布的影响,采用Gamma分布能较好地描述实验。     

表面活性剂对泡载分离谷氨酸菌体的影响

本文考察了表面活性剂种类及浓度对泡载分离谷氨酸菌体的影响．结果表明，阳离子型表面活性剂对泡载分离菌体的影响趋势相同，不同离子型表面活性剂对分离菌体的作用机理不同；添加一定量絮凝剂可大大提高菌体分离效率；在发酵液中添加一定浓度表面活性剂和絮凝剂，可获得最佳分离效果．利用建立的动力学模型对实验数据进行了关联，结果较好     

泡载分离器的研究——泡载分离器内微气泡的分布规律

利用H_2O-CO_2体系,对溶气法产生气泡的分布规律进行考察。实验结果发现,微气泡的分布呈非对称拖尾分布。从气液传质、能量转换和气泡动力学的角度,对气泡形成饥理进行分析。提出了描述气泡拖尾分布的Γ函数分布,并讨论其分布函数中参数m的物理意义。     

泡载分离器的研究——高压溶气水减压释气过程

本文研究了用于泡载分离过程、由高压饱和溶气水减压产生微小气泡过程的流体力学特性。实验采用CO_2-H_2O体系,考察了0.1～0.3MPa压力(表压)下,饱和CO_2水溶液通过三个不同长径比的喷嘴,减压产生的气体流量、气泡直径以及溶液中气泡浓度的变化规律,并对这些规律作了理论分析和经验关联。     

超声诊疗一体化的载药壳聚糖纳米微泡的制备

载药微泡在超声诊疗一体化中具有广阔的应用前景.以壳聚糖为原料制备了一种能够实现超声诊疗一体化功能的载药壳聚糖纳米微泡,采用激光粒度仪、透射电镜、扫描电镜、紫外分光光度计、超声成像仪以及圆二色谱仪等对载药纳米微泡进行表征,研究了载药纳米微泡的稳定性,并验证了其体外超声显影和超声释放的能力.结果 表明,载药纳米微泡平均粒径...     

螺旋藻及螺旋藻多糖体外清除活性氧及抗氧化作用研究

利用Fenton反应、光照核黄素产生活性自由基·OH、·O-2,以分光光度法研究了螺旋藻及螺旋藻多糖体外清除·OH、·O-2的作用.通过FeSO4诱导脂质过氧化模型、硫代巴比妥酸分光光度法研究了螺旋藻及螺旋藻多糖抗脂质过氧化及对·OH引起的DNA氧化损伤的保护作用.结果表明,螺旋藻及螺旋藻多糖能有效清除·OH、·O-2自由基,对脂质过氧化及DNA的·OH氧化损伤有显著抑制作用.     

微藻采收技术的进展与展望

从微藻培养液的特性出发,总结了目前微藻采收工艺中预处理和富集分离阶段的各种方法,包括预氧化、化学絮凝、物理预处理、沉降、过滤、离心、泡载和气浮等. 已有研究结果表明,经预氧化处理后,细胞分泌胞外产物,有利于絮凝沉降,但药剂过量会引起细胞损伤甚至消亡;化学絮凝和物理处理可以大大提高后续富集分离的效率. 由于微藻培养液浓度低、粒度小,传统的沉降、过滤、离心等方法用于微藻的采收都存在效率低、成本高的限制,而气浮法适用于低浓度悬浮体系的富集分离,是微藻采收可行的技术途径之一.     

螺旋藻藻蓝蛋白的分离纯化研究进展

藻蓝蛋白在医药、食品及化妆品等领域有着广泛应用,螺旋藻中藻蓝蛋白的含量丰富。本文介绍了藻蓝蛋白的结构和生理活性,综述了国内外螺旋藻中藻蓝蛋白的提取和纯化技术的研究进展,列举了几个影响藻蓝蛋白稳定性的因素。     

泡沫浮选在钾盐生产中的应用

按照泡沫浮选的定义,从原理、影响因素及生产工艺方面综述了泡沫浮选分离技术的研究进展,其中对泡膜分离浮选技术的原理、捕收剂及国内工艺改进方面进行了重点阐述,并提出了展望。     

泡沫浮选法处理含铬废水的试验研究

本实验采用泡沫浮选技术脱除废水中的Cr^3 ，用十二烷基硫酸钠(SDS)作表面活性剂，Fe(OH)3作絮凝剂，得到间歇操作流程适宜的操作参数为：溶液pH值为5．5左右，SDS为180mg／L，气体流量800mL/min。在此操作条件下，Cr^3 的脱除率可达97％左右。     

泡沫浮选分离技术应用进展

综述了泡沫浮选在分离固体粒子、分离溶液中的离子、分子,处理工业废水、油田开发、脱墨、土壤的清洗、回收、浓缩生物活性物质、分离全细胞的应用,并提出将来的发展方向。     

Diesel Oil Removal by Froth Flotation Under Low Interfacial Tension Conditions I: Foam Characteristics,and Equilibration Time

Abstract

Froth flotation is a surfactant‐based separation process which is suitable for treating dilute wastewaters. To achieve high performance for the froth flotation operation, the combination of an ultra‐low interfacial tension (IFT) between excess oil and excess water phases, high foam production rates, and high stability of the foam produced, must be attained. To obtain the ultra‐low interfacial tensions, a Winsor Type III or middle phase microemulsion has to be formed. In this study, branched alcohol propoxylate sulfate sodium salt with 14–15 carbon number and 4 PO groups (Alfoterra 145–4PO) was used to form microemulsions with diesel oil. From the results of this work, an increase in surfactant concentration decreased the IFT, and increased foam stability. To obtain the minimum IFT in the region of a Winsor Type III microemulsion, the addition of 5 wt.% NaCl was needed. However, this optimum salinity does not result in effective froth flotation due to poor foam characteristics. The results indicate that both the IFT and the foam characteristics should be optimized to achieve high efficiency of oil removal in a froth flotation operation. Unlike the previously‐studied ethylbenzene system, agitation of the solution before introduction into the flotation column yielded the lowest diesel oil removal efficiency because of the poor foam characteristics compared to either unagitated systems or systems allowed to equilibrate for one month.     

泡沫浮选法处理含氰废水

本文研究了在含氰废水中按化学计量比加入Fe~(2+)和Fe~(3+)离子以生成无毒的亚铁氰化铁絮状物沉淀,然后采用泡沫浮选进行分离的除氰方法。操作过程中拟加入一定量的阳离子表面活性剂,采用5~#烧结玻璃板作气体分布器,在pH值为4.0～6.5之间,能获得较高的分离效率。操作宜在阳光直射不到的阳暗处进行以避免亚铁氰化铁沉淀的光解反应发生。     

高炭粉煤灰浮选脱炭试验研究

高含炭量的粉煤灰是一种不可被直接利用的固体废弃物.为降低高炭粉煤灰的烧失量,对高炭粉煤灰进行脱炭试验研究.本文通过磨矿试验确定高炭粉煤灰原灰最佳磨矿时间为1.25 min;通过浮选药剂制度试验确定磨细高炭粉煤灰最佳浮选药剂制度为仲辛醇用量为4 kg/t,煤油用量为12 kg/t;通过浮选工艺试验,确定磨细高炭粉煤灰最佳...     

温度对高浓度SDS水溶液泡沫稳定性及分离的影响

高浓度表面活性物质的分离是泡沫分离过程的难题,也是制约泡沫分离技术应用于工业化生产的瓶颈.为了解决高浓度表面活性物质泡沫分离的难题,以阴离子表面活性剂十二烷基硫酸钠(SDS)水溶液为体系,研究了在其临界胶束浓度(CMC)附近时,温度对SDS水溶液气泡直径、泡沫稳定性、富集比及回收率的影响.结果表明:温度对高浓度表面活性物质的泡沫分离有显著影响.当SDS水溶液浓度分别为1.2、2.3、3.5g·L-1,温度从30℃升高到70℃时,泡沫稳定性先增大后减小,在pH 6.9、表观气速2.4×10-3 m·s-1、装液量200 mL的操作条件下,气泡直径先减小后增大,富集比提高了3～5倍,回收率降低了34％～65％.     

Replacing Mechanical Flotation Cells by a Flotation Column at the Pilot Plant of the Sarcheshmeh Copper Mine

Abstract

A flotation column could be considered as one of the major breakthroughs in the field of mineral processing in the last decades. Due to an increase in the trend of the use of these type of cells in the mineral processing plants, an investigation regarding the performance of these cells was initiated. The flotation column at the Sarcheshmeh pilot plant with some modifications was restarted. When all necessary measures were taken, the possibility of using the flotation cell in the cleaner and recleaner stages was investigated. Replacing the cleaner cells by the column flotation increased the separation efficiency by 7%. When the column cell was used as recleaner and both cleaner and recleaner, an improvement of 10% was observed. It was found that using a column cell instead of mechanical cells in addition to a decrease in repair and maintenance costs could result in 76% and 83% reduction in energy cost of cleaner and cleaner‐recleaner stages, respectively, at the pilot plant.     

Study on Streptomycin Sulfate Recovery by Batch Foam Separation

The feasibility of foam separation as a technique was assessed for the recovery of streptomycin sulfate from the waste solution by using an anionic surfactant sodium dodecyl sulfate (SDS). The experimental parameters examined were SDS concentration, superficial gas velocity, initial pH, and liquid loading volume. The results showed that sodium dodecyl sulfate as the surfactant for foam separation had good foaming quality and could effectively concentrate streptomycin sulfate of the aqueous solution by technology of foam separation. The enrichment ratio and the recovery rate of streptomycin sulfate were 4.0 and 85%, respectively under the best operating conditions of sodium dodecyl sulfate concentration 0.4 g/L, superficial gas velocity 300 mL/min, liquid loading volume 300 mL and initial pH 6.0 when streptomycin sulfate concentration was 0.5 g/L.