Batch cleaning system

Low pressure spray in air batch cleaning systems (see Figure 14.8.14) can be attractive propositions for users who only have a low volume of pc-boards to clean and are required to furnish proof of a specified cleaning process to their customers. The water-based mildly alkaline cleaning agent VIGON A200 was specifically developed for this application. 

Figure 14.8.15. Scheme of a low-pressure batch cleaning system. 

Speedline Aquajet Spray semiautomatic batch-cleaning systems typical applications include bare boards, stencils, misprints, pallets, and PCB assemblies Water soluble, saponified, compatible with aqueous detergents and deionized water Compatible with most combustible semi-aqueous solvents EC7-R typical N/A... 

What does low cost of ownership mean Too many define it as outsourcing production to China. This article offers a checklist for establishing the lowest cost of ownership in batch cleaning systems. 

A further level of sophistication is illustrated by a submersible UV/vis spectrometer, currently being developed for batch process analysis but potentially also applicable to continuous processes. This instrument also overcomes the sensor-fouling problem by using an auto cleaning system based on pressurised air [76]. 

Production records Processing records and production logs Product specification sheets for existing and new products Bleed runs used to purge equipment which cannot be cleaned before use Best-before dates or batch numbering systems... 

In offshore operations, it is desirable to discharge the produced solids overboard. Schlittler (135) described a batch process system that removed free oil from produced solids by means of a scrubber system fitted with rotating blades. The energy imparted by the blades promotes particle contact and shears the oil from the solid surfaces. The mixture of oil, solid, and water is separated by gravity in a wash tank. The cleaned solids are reported to contain less than 1 ppm oil, meeting or bettering standards for overboard discharge. 

From the physical point of view, the most important considerations are temperature, pressure, and sample cleanness. Suspended solids in liquid samples and dust in gas samples often interfere with transducers in continuous-sampling instruments and with the volumetric sampling techniques used in batch-sampling instruments. Automated systems that filter out solids should be amenable to automatic cleaning. In continuous instnunents, data output must be interrupted while the filters are cleaned in batch-sampling systems, filters can be cleaned during the deadtime after a sample has been injected for analysis. 

Easy to use, long-tank life, alkaline aqueous cleaner designed for batch washers Easy to use, low pH aqueous cleaning solution for ultrasonic immersion cleaning systems... 

Spray batch and spray in-line cleaning systems for OA, no-clean, and RMA pastes and lead-free flux residues Removes all types of flux residues including lead-free in batch washing Flux residue removal in ultrasonic immersion cleaning systems requiring no sump side additives... 

The fed-batch and batch cultivation systems share the same cleaning and sterilization process in which the bioreactor operation is stopped and the bioreactor is emptied. This stoppage creates considerable costs and operational downtime. The repeated or cyclic system, which can be applied to both batch and fed-batch cultivation systems, may be installed in order to maximize the productivity. The cyclic cultivation system does not enter the cleaning and sterilization process, but rather empties a portion of the bioreactor while preserving part of the batch for the next cycle. Another method to increase productivity is cell retention techniques such as fluidized beds, membranes, or external separators. These options allow multiple cycles without cleaning and sterilization, which is initiated only if it is deemed that mutation risks exceed tolerable levels (Bellgardt, 2000b). 

The continuous bioreactor offers more operational control and flexibility over batch bioreactors. Practical production is made simpler and more profitable due to the possibility for automation and the lack of cleaning and sterilization processes (Bellgardt, 2000b). The added equipment cost is offset with operational savings while control schemes, which are limited to a few hundred variables, are often much simpler than the corresponding batch bioreactor systems (Simon et al., 2006 Williams, 2002). 

A process that has found widespread use in practice is semi-aqueous cleaning with ZESTRON FA. This cleaner was especially developed for removal of no-clean soldering fluxes in ultrasonic batch or spray under immersion cleaning systems. It is used in the cleaning bath, rinsed with demineralized water, and then dried with hot air (see scheme in Figure 14.8.13.). 

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. 

Clean and inspect equipment after each change Segregate incompatible materials Label material, lines, pumps and valves Use double check system Check labels against batch sheets Use procedures and training Set valves to correct flow path... 

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