对难过滤物料强化过滤技术的研究及应用

对一种高可压缩、具有软体颗粒难过滤的生物酶解液物料,进行了过滤过程研究.采用添加助滤剂的掺浆助过滤和限制滤饼增长的薄层滤饼过滤相结合的强化过滤技术,可以解决此类难过滤物料的液固分离问题.     

过滤高黏度物料的多层复合过滤介质

介绍了可压缩、高黏度及胶状物等难过滤物料的性质、过滤难题和强化过滤分离的方法,针对实例设计了六层复合结构滤布并测试了其过滤效果。     

采用超高分子量聚乙烯过滤介质强化过滤过程的研究

采用颗粒烧结法制备的超高分子量聚乙烯过滤介质,对用途广泛、难过滤的一种无机盐醋酸钙物料做了动态强化过滤过程研究。在对3种超高分子量聚乙烯过滤介质表征的基础上,考察了不同操作压力、旋转速度、固含量、操作温度等对过滤过程的影响。研究表明,过滤通量随着过滤介质孔径增大、压力增大、温度升高、固含量降低均有所增加,截留效果较好,滤液浊度都在30.0 NTU以下,实现了有效的过滤分离,可供技术工程化应用研究参考。     

酶解液过滤过程的强化及新型水平带式真空过滤机的应用

以生物保健品生产过程中难过滤的酶解液为研究对象,考察了该酶解液的物料特性和过滤特性.对该物料进行了过滤过程的强化研究,筛选了合适的助滤剂,探讨了助滤剂添加量、助滤剂使用方法、操作压力对实际分离过程的影响,确定了酶解液的分离工艺,还结合强化过滤过程研究,研发了一种新型水平带式真空过滤机并将其应用于生产实际,解决了生产中的...     

助滤剂在高黏度可压缩物料过滤中的应用

对于高黏度、高可压缩、固相浓度低、以澄清液相为产品的过滤过程,通常采用加入助滤剂的强化过滤技术进行液固两相分离。在进行助过滤时,应该根据待分离物料的不同物性,选择不同种类的助滤剂,且保证助滤剂的添加量适当,才能起到助过滤的效果,减小滤饼阻力、加快过滤速度、确保滤液澄清。     

化工生产上的液体精密过滤与最新过滤技术

液体的精密过滤是化工生产上普遍应用的一种重要的单元操作。叙述当前化工生产上液体精密过滤的概况 ,介绍最新开发的液体精密过滤技术及其在液体精密滤饼过滤与液体精密澄清过滤领域的应用 ,并介绍应用最新液体精密过滤技术的主要计算公式     

过滤分离技术在无机盐工业的应用展望

提出了在无机盐工业生产中应用过滤分离技术与设备时应注意的几个问题。结合国内外分离机械发展趋势（大型化、多功能集于一体、用途专业化）,介绍了几种节能型过滤设备（带压榨机构的箱式压榨机、陶瓷过滤介质与陶瓷过滤机、带式压榨过滤机、罐式三合一设备）及新型过滤介质。     

橡胶促进剂M过滤分离工艺实验研究

由于橡胶促进剂M在酸化后含有大量的水分,前期研究表明通过添加表面活性剂预处理可以有效降低固液分离后滤饼的含水量。为了研究经表面活性剂处理后悬浮液的过滤方法与效果,分别采用加压过滤、真空抽滤、离心过滤的分离方法进行了过滤分离实验,并对不同分离方法下滤饼质量进行检测。研究结果表明,采用真空抽滤方法对添加表面活性剂预处理后的橡胶促进剂M悬浮液进行过滤分离,并通过水洗滤饼,可以大幅度降低滤饼的含水量,并能满足橡胶促进剂M的质量要求。     

旋转圆筒型过滤膜精密平衡过滤的研究

旋转圆筒型过滤膜在精密平衡过滤难分离物质时,由于高速旋转的过滤膜对附着在过滤膜表面的滤饼层产生很大的扫流力,过滤时不断扫流过滤膜表面生成的滤饼,使过滤能够保持连续稳定的过滤速度。本研究通过难过滤性物质ＰＭＭＡ液浆和Ｏ／Ｗ乳浊液的高速连续稳定的精密平衡过滤,对旋转精密平衡过滤的特性和操作参数进行了有益的探讨。     

微米级高分子精密过滤技术及其在精细化工、水处理与环保领域的应用

微米级高分子精密过滤既能澄清过滤 ,也能滤饼过滤 ,还能卸干滤饼 ,过滤介质能高效再生 ,耐化学性能好 ,是一种使用寿命长的新型过滤技术。主要介绍了该技术的组成特点及其在精细化工、水处理及环保领域的主要应用。     

Cleaning of coal-derived oils by filtration

With the development of coal liquefaction processes a major task is the removal of solid particles (mineral components, residual insoluble coal and catalyst) from the hydrogenation products. Depending on the characteristics of these products various cleaning methods are under investigation. Thermal methods (distillation, solvent deashing) are preferred for those hydrogenation processes yielding predominantly distillable oils. The separation of solids from the recently developed SRC I processes presents more problems because the percentage of oils is much too low for distillation to be used exclusively for recovering the recycling oil. Therefore, deashing of the SRC I products using solvents within the critical range as well as filtration processes are under development. The Paper describes the different processes under development at the moment and introduces a newly developed candle filter for SRC I filtration. Besides the design of the filter unit, results of filtration tests, handling of the filter cake and production of a filter aid and coke from the residue are described also.     

Efficiency of wood cellulose filtration

木浆纤维素作为助滤剂应用广泛,其过滤性能亟待研究。不同的过滤条件对木浆纤维素滤饼层的过滤性能会有很大影响。本文通过单因素法考察了过滤压力对滤饼层截留精度和平均滤速的影响,并通过正交实验法考察了木浆悬浮液黏度、木浆浓度、木浆添加量、悬浮液含水对滤饼层截留精度和平均滤速的影响。实验表明木浆纤维素属于中等可压缩性物料,其过滤性能随过滤条件变化呈规律性变化。通过对实验结果的分析,确定了优化方案。研究结果为木浆纤维素过滤的小型工业试验提供参考。     

过滤分离技术在无机盐工业清洁生产中的应用

过滤与分离作为基本的化工生产单元过程之一,在无机盐生产中不可或缺。清洁生产要求过滤与分离过程能采用先进的工艺技术、高效集成分离设备、新型过滤介质、环保型后处理工艺,并确保过程的高效节能。对氯碱盐泥、尾矿矿浆过滤与分离过程中的清洁生产技术进行了应用研究。在压榨过滤工业性试验中探索了压榨过滤操作的最适宜起始压榨点,确保压榨效果最好、过程用时短、滤饼含液量更低;针对铝土矿浮选后尾矿的物性,分别采用助过滤、絮凝、凝聚技术等预处理方法对尾矿处理与水的回用过程进行了最适宜的使用条件与方法的探索,应用效果好,处理量高,水回用可达到国家标准,可供工业生产借鉴。     

纤维素助滤剂的预敷过滤性能

对高黏度物料加入纤维素助滤剂的预敷过滤性能进行了研究,说明不同的预敷条件对预敷层的过滤性能会有很大影响。通过改变预敷压力和浓度,对纤维素滤饼层的过滤比阻、可压缩性系数和孔隙率进行了研究。实验表明,纤维素预敷层的比阻随压力增加而增加,随浓度增加而减小;孔隙率随压力增加而减小,随浓度增加而增加;可压缩性系数随浓度增加而增加。纤维素助滤剂为中等可压缩性物料,孔隙率大。研究结果可为高黏度物料用纤维素预敷过滤的工程应用提供参考。     

Dynamic cross flow filtration

The dynamic cross flow filtration with the DYNO filter is a very versatile and economic high performance filtration process especially for suspensions with critical separation characteristics. Thickening, washing and clarifying of suspensions but also a classifying sieve filtration can be performed with the DYNO filter in a continuous operation with permanently high throughput rates. The principle of the dynamic high shear filtration ensures almost ideally physical conditions for the separation process. Contrary to classical cross flow filters a repeated recirculation of the suspension is not necessary for attaining the separation target. In the DYNO filter suspensions can be highly concentrated up to the flow limit in only one filtration cycle. In most cases, the concentrate is as dry as a firm filter cake and the filtrate is crystal-clear. Sieve filtration tasks for separating of coarse grain are performed with high concentration factors of up to 1000. Thus, the coarse fraction is obtained highly concentrated.     

Local solidosity of microcrystalline cellulose during dead-end filtration and sedimentation

Solid–liquid separation by filtration and sedimentation are important operations used in a wide range of industries. One important characteristic of both the filtration and sedimentation processes is the solidosity of the filter cake/sediment that is formed, affecting the efficiency and design of the separation. In this study local solidosity was investigated using a γ-attenuation method during both filtration and sedimentation experiments for microcrystalline cellulose, a highly crystalline cellulose with particles of about 2–80 μm in diameter. Constitutive relationships for the solidosity were investigated using both filtration (i.e. cake build-up and expression) and sedimentation data for experiments at different pH and suspension concentrations. The sedimentation behaviour under these different conditions was also investigated. It was found that a three parameter empirical model could be used to describe the constitutive relationship between local solidosity and local solid compressible pressure for the sediment formed and the filter cake after both cake build-up and expression. This correlation worked well for the material investigated even at low solid compressible pressures.     

硅藻土-木桨纤维为助滤剂强化过滤过程的研究(英文)

In this paper, a study to enhance the filtration for solid/liquid materials difficult to be filtered, such as highly viscous, highly compactible or gel like materials, is presented. Filter aids diatomaceous earth and wood pulp cellulose are used to enhance the filtration by improving filter cake structure and properties in the filtration of a biological health product and a highly viscous chemical fiber polymer melt product. The property of solid/liquid systems, filtration at different flow rates, specific cake resistance, cake wetness, filtration rate, filtrate turbidity for filter aid selection and evaluation, and operation optimization are investigated. The results are successfully applied to industrial process, and can be used as a reference for similar filtration applications.     

Nanocolloid cake properties determined from step‐up pressure filtration with single‐stage reduction in filtration area

A sophisticated method was developed for evaluating simultaneously and accurately both the average specific resistance and average porosity of the filter cake formed in unstirred dead‐end ultrafiltration of nanocolloids such as protein solution and nanosilica sol. In the method, a step‐up pressure filtration test was conducted by using a filter with a single‐stage reduction in the effective filtration area. The influence of the pressure drop across the cake on not only the average specific cake resistance but also on the average cake porosity of highly compressible filter cake was evaluated using only flux decline data in one dead‐end filtration test, taking advantage of the decrease in the cake thickness caused by the pressure increase. As a result, the cake properties were easily determined for a variety of nanocolloids. Constant pressure dead‐end ultrafiltration data obtained under various pressures and concentrations were well evaluated based on the method proposed. © 2015 American Institute of Chemical Engineers AIChE J, 61: 4426–4436, 2015     

Experimental and analytical modeling of the filtration mechanisms of a paper stack candle filter

A candle filter consisting of a paper stack is an adequate device to clarify the grinding oil employed in the industrial post-processing of hard metal because of its cleaning efficiency and its regenerative capability by means of backwashing. The complex particle deposition mechanisms occurring in this device have not yet been investigated. Filtration experiments with a suitable particle-oil suspension were performed in a pilot filter and in a laboratory filter in order to investigate and model the mechanisms taking place in the process. The effect of operating parameters such as particle concentration and pressure difference on filter performance was evaluated. The results show that more than one filtration mechanism takes place simultaneously. While some depth filtration occurs at the beginning of the lifetime of a candle filter, blocking and cake filtration are the major mechanisms responsible for the filter clogging. Although blocking and cake filtration occur, to some extent, simultaneously, the cake filtration is the mechanism relevant for the modeling and scale-up of the long term filtration process.