Process, flushing

In the manufacture of coating materials, paints, varnishes, lacquers, dyestuff pigments, binding materials, and binders, surfactants are of great importance. Most of the systems used in these fields are dispersed. Therefore surfactants can accelerate the preparations of dispersions and improve their stability. For rewetting processes, like the so-called flush process, besides other anionic surfactants sulfosuccinates are also used. 

The reactive mixture in the flusher is cooled with salt solution (-15 °C) down to 5 °C. At agitation flusher 7 is filled (pumped with a centrifugal pump) with condensate cooled to 5-8 °C from collector 8. The collector is fashioned with coil 4. The flushing process is conducted periodically at 5 °C. 

Lower alcohols (e.g. methanol, ethanol, propanol), ketones (e.g. acetone), and alkyl amines are often used in solvent-flushing processes (Li, Cheung, and Reddy,... 

When 3% of Tween 80, a nonionic surfactant commonly used in soil-flushing processes, was applied to an electrokinetic system used to remove phenanthrene from kaolin and glacial tiU, significant desorption, solubilization, and migration of the pollutant occurred near the anode. The phenanthrene concentrations in the... 

Surfactants are used in the so-called flush process in the dye and varnish industry. Organic and inorganic pigments are transferred from an aqueous medium into an oily medium in this procedure. In addition, surfactants disperse pigments in dyestuffs, emulsify pigments in emulsion dyestuffs and stabilize the formulations of dyes and varnishes. 

The vapor cleaning method becomes a practical requirement when the concentration of the PCB contamination is greater than about 1000 ppm PCB. The method has a significant cost advantage over the conventional drain and flush process since vapor cleaning yields a minimum volume of contaminated fluid for disposal. 

The boiler and circulating pump are isolated with valves, and city water is flushed through the successive zones of the system, carrying chips, dirt, pipe joint compound, etc., to waste with it. This is followed by a chemical flush. Removal of pipe chips and other debris before operating the isolation valves of the boiler and pump will help to protect this equipment from damage by such debris. After this flushing process is complete, the usual boU-out procedure is accomplished. 

Caution If one zone is flushed and boiled out before other zones are completed or connected, this flushing process should be repeated on completion of additional zones, loops, or sections of the piping. 

Pump unit with automatic flushing device Media that tend to incrustations and blockages often require flushing processes. Figure 4.15 shows the P I-typical of a redundant pump group with an automatic flushing device. 

Afterwards, the individual system controls are activated until finally, the main control program is activated. Now, the main controls, such as e.g. flow-through and level controls can be tested and optimized. For this purpose, e.g. the proportional coefficients, rate times and reset times of PIDcontrol procedures, usually the timing elements have to be optimized, too, e.g. duration of the flushing processes. 

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