Short Cleaning Cycles

Downtime required for cieaning may not agree with the expected frequency of cieaning. Short cieaning cycles may be caused by  

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Typically, a filter cake or precoat is built up on the filter septa to prevent blinding, short filter cycle times, and cosdy cleaning of the septa. Then diatomite is added as body feed to the Hquid to be filtered so that the permeabiHty of the filter cake may be maintained. Filler aid permeabiHty of diatomite ranges from 0.06 to 30 lnF. At the end of the filter cycle the filtrate is clear and the soHds are retained in the soHd or semisoHd diatomite filter cake. The type and amount of diatomite for precoat and body feed are normally deterrnined by pilot studies (18,19). 

Density of the flakes (compared with how fast the solvent rose up the column) put constraints on the efficiency of these columns. Under perfect conditions, all the solids would sink, and only solids-free miscella would flow out the top. One never reaches perfect conditions. Reasonable capacity requires appreciable rates of vertical ascent. Fines sink slower than flakes. Agitation creates fines and causes turbulence in the miscella. A major shortcoming of vertical immersion columns is excessive fines in the miscella. The miscella had to be filtered through the solvent-tight plate-and-frame filters, two filters in paralle, one on stream, the other being cleaned. Poor flake preparation caused short filter cycles. Cleaning the filters allowed solvent to escape and created a potential fire hazard. 

Operation at increased capacity Short Time Between Cleaning Cycles ... 

Once the mould has been cleaned it becomes very susceptible to corrosion. Some factories overcome this problem by oiling the mould surfaces. This in itself gives rise to problems when the mould is needed for production. The best solution is to immediately apply a coating of a semi-permanent silicone resin release agent followed by a short bake cycle. This gives a mould that is immediately ready to produce first class mouldings. 

The benefits stated above are due solely to the qualitative early identification of shorts and bad contacts. Beyond this, the HELM tracker will collect quantitative data (primarily current and time), which can be exploited for further benefits. The system can identify the total charge (Amp hours) that has passed through individual cathodes, cells, and banks, to provide an indication of the overall inventory of plated production at any time. By detecting stripping and cleaning cycles, the system can not only identify which cells are next ready for harvesting, but also nominate the optimum time for uniform plate thickness. 

High temperature, short curing cycles in injection, transfer, or even compression molding operations require so-called clean elastomers with low mold-fouling properties and fast cure rates. There is a selection of grades available illustrated in Tables 2.5 and 2.6. Other suppliers such as Polimeri Europa, Nitriflex, and JSR also have developed these types of NBR. 

A self-cleaning cycle can be performed by a timing mechanism, using compressed air blown in short bursts through horizontal blow pipes into the filter chamber. This brief pressurization causes the accumulated particles to become dislodged from the filter elements. The dust is then pulled by a separate air fan into a secondary cleaning circuit, which exhausts the particles to the atmosphere away from the inlet... 

Reaction times can be as short as 10 minutes in a continuous flow reactor (1). In a typical batch cycle, the slurry is heated to the reaction temperature and held for up to 24 hours, although hold times can be less than an hour for many processes. After reaction is complete, the material is cooled, either by batch cooling or by pumping the product slurry through a double-pipe heat exchanger. Once the temperature is reduced below approximately 100°C, the slurry can be released through a pressure letdown system to ambient pressure. The product is then recovered by filtration (qv). A series of wash steps may be required to remove any salts that are formed as by-products. The clean filter cake is then dried in a tray or tunnel dryer or reslurried with water and spray dried. 

ASE using dichloromethane has been applied to extract alkylphenols and short-chain NPEO from sediment [8,47]. Samples of 2-5 g were extracted in two cycles of 30 mL at 100°C and 69 atm. Clean-up was performed using size exclusion chromatography to remove high molecular weight lipids, and then using normal phase HPLC. 

PERO Innovative Services has developed the equipment and the peripheral devices in such a way that they optimally adapt to the desired cleaning process and minimise the costs during the complete life cycle of the equipment (according to LCC - Life Cycle Costing, formerly accurately related to as TCO - Total Costs of Ownership, since traditional accounting systems in most cases regard a period which is too short, as the costs as well as the benefits of the system incur over a long time utilisation of the equipment). 

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