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Segregation in silos can occur during filling, storage or discharge. In all three stages, measures can be taken to combat this phenomenon. In silos segregation of bulk solids that consist of different fractions or component scan be a problem. De-mixing will result in a unsteady composition of product flowing out. At one stage this may be too coarse, at another to fine. Or the percentage of a components is too high or too low. Segregation can occur during filling, during storage and during discharge of the silo. However, in all three stages, measures can be taken to combat this phenomenon. by: ir. P.J. van der Kooi [INTERMEZZO**M99****In a previous article [AHREF**--**/article/30553/segregation-mechanisms-the-basics-of-de-mixing.html** segreation mechanisms] were treated. This article deals with the aspects specifically related to storage and flow in the silo.**] Segregation in silos As mentioned in the previous article, segregation (de-mixing) is a result of the difference in properties of the different components or fractions in a mixture. Segregation can be caused by various mechanisms and occur

Segregation or de-mixing is the difference in composition of several samples of one bulk material. This article gives insight in the general influences and aspects of segregation. If samples taken from one batch have a different composition, this is called segregation or de-mixing. The samples may differ on the basis of the components present (different products) or the fractions present (different particle sizes). Segregation means that the properties of a batch of bulk material are no longer constant at every location, resulting in a loss of quality. Combating segregation involves many aspects. by: ir. P.J. van der Kooi This article deals with general influences and aspects of segregation. The second article in this series deals with the aspects specifically related to storage and flow in the silo. Product properties and segregation Global distinction In mixtures of identical particles, by definition, no segregation can occur. De-mixing is a consequence of the difference in properties of the various components or fractions in a mixture. It can be caused by various mechanisms, in which the process also plays an important role.

The first stage of the hopper design process commences with establishing the form of flow regime that should be generated when discharging. . Basic choices 1. Mass Flow. For products that deteriorate in some way over time and are to be held in hoppers that may be re- filled before fully emptying. 2. Expanded Flow. For products with poor flow properties that either do not deteriorate in extended storage or the non-mass flow contents will be discharged before the hopper is re- filled. 3. Funnel Flow. For free flowing products that do not deteriorate during extended storage time. Geometric form The second stage is to choose a geometric form for the storage container, usually either circular, with conical hopper section or rectangular, with pyramid or slot outlet. The outlet region may be transformed to a chisel shape to exploit the flow benefits of plane flow and slot outlets. Eccentric shapes and multiple outlets are normally best avoided. This choice tends

Many issues that arise in the performance of bulk handling plants relate to the condition of the material and disputes centre on the party responsible. By Lyn Bates, Ajax, Bolton, UK A key factor is whether the unacceptable material condition is the result of the supply being outside the range defined in the contract specification , or is a result of changes taking place during the handling processes. Various properties of the material must be known or assumed with a high degree of confidence for design purposes and a responsible supplier would be assured of these values before proceeding to manufacture, either by experience, or testing ‘representative’ samples in the case of any uncertainty. The following steps are recommended to secure and record the essential details. 1. Have clear reasons for conduction of the tests, to make sure that the tests conducted are necessary and relevant to the purpose of interest. 2. Identify and record the true source and history of powder sample(s) for testing. Secure an authorised and dated signature by a responsible person to verify that it is, Or they are), fully ’Representative’ sample’ of

Higher silos may show problems such as quaking or honking, or too high stresses on the product stored. Intermediate cones are a reliable and well designable solution. If, for whatever reason, a company invests in larger silos, one must be aware of problems. The bulk material experiences greater pressure in a larger silo. This means that the properties of the bulk material change in a negative way. It is therefore very important to keep that pressure under control. An important instrument is the wall of the silo. One can apply rings or coat the wall. This article deals with the application of intermediate cones. With a well-designed intermediate cone one can reduce the pressure, the product flows again, and shocks will be a thing of the past. Bigger silos, bigger problems Increasing capacities or shorter lead times sometimes require larger stocks of raw materials. For companies that store their raw materials in silos, this means an investment in higher or wider silos. This may lead to problems not experienced before, because the bulk solid experiences greater pressure in a larger silo. This changes the properties of the bulk solid,

PENKO Engineering recently completed the SGM800 Digitizer range. The SGM800 Digitizer is a range of compact modules mounted on a DIN rail and that seamlessly connect load cells and strain gauges using industrial process control. Connecting weighing instruments directly to automation, is one of the action points of Industry 4.0 and Smart Industry. Also weighing data are important components of Big Data. For this, it is necessary that all the weighing data collected in the field, also becomes available at a higher IT level. To achieve this with as many companies as possible, PENKO Engineering now offers the SGM800 Digitizer: a range of certified communications modules for different protocols which can be used simultaneously for decentralized control. Protocols What PENKO first has tackled, are various protocols for industrial networks. PENKO solves this with six different versions of the SGM Digitizer, As a standard all six versions communicate via USB and RS485. The

The company BOSCHE is capable of producing according to DIN EN 1090 Since July 01, 2014, all carrying components made ​​of steel or aluminum have to go through the attestation of conformity according to DIN EN 1090. Silo scales are carrying the complete silo load and therefore must be certified according to DIN EN 1090. The BOSCHE production process and quality control for hopper scales is established to produce according to DIN EN 1090 and to issue CE declarations for these. This CE declaration is required to sell products according to DIN EN 1090 throughout Europe.