Processing equipment improvement

Chem. Descrip. Tallow and coconut fatty acid salts Uses Lubricant, process aid for all elastomers dispersant, pigment wetting agent for better disp. in mixing improves release from processing equip. improves compd. flow... 

Uses Processing aid, dispersanL plasticizer, release agent for rubber prevents agglomeration of fillers in highly loaded compds. reduces slicking to process equip. improves extrusion, release Featwes Provides easier incoqraralion of fillers F roperties Lt. bm. paste sp.gr. 0.89 bulk dens. 890 g/l drop pt. 42 C Use Level 0.63%... 

Chromium is the most effective addition to improve the resistance of steels to corrosion and oxidation at elevated temperatures, and the chromium—molybdenum steels are an important class of alloys for use in steam (qv) power plants, petroleum (qv) refineries, and chemical-process equipment. The chromium content in these steels varies from 0.5 to 10%. As a group, the low carbon chromium—molybdenum steels have similar creep—mpture strengths, regardless of the chromium content, but corrosion and oxidation resistance increase progressively with chromium content. 

The initial step of production is carried out in a titanium reactor (34) because of the high corrosivity of maleic acid to most metals under the drastic reaction conditions used. The other steps are performed in stainless steel equipment. Improved purification processes for malic acid have been patented (37,38). 

PTFE is outstanding in this group. In thin films it provides the lowest coefficient of friction (0.03—0.1) of any polymer, is effective from —200 to 250°C, and is generally unreactive chemically. The low friction is attributed to the smooth molecular profile of PTFE chains which allows easy sliding (57). Typical apphcations include chemical and food processing equipment, electrical components, and as a component to provide improved friction and wear in other resin systems. 

More microprocessor-based process equipment, such as smart instruments and single-loop controllers, with digital communications capability are now becoming available and are used extensively in process plants. A fieldbus, which is a low-cost protocol, is necessary to perform efficient communication between the DCS and these devices. So-called mini-MAP architec ture was developed to satisfy process control and instrumentation requirements while incorporating existing ISA standards. It is intended to improve access time while... 

Analysis of biological activity does not automatically lead directly to a corrosion-rate measurement. However, with detection and correlation with process conditions, such information may also lead to improvements in the corrosion lifetime of the process equipment. 

The addition of small amounts of alloying materials greatly improves corrosion resistance to atmospheric environments but does not have much effect against liquid corrosives. The alloying elements produce a tight, dense adherent rust film, but in acid or alkaline solutions corrosion is about equivalent to that of carbon steel. However, the greater strength permits thinner walls in process equipment made from low-alloy steel. 

In process equipment, squeeze film dampers are primarily used to improve rotordynamic stability. They are commonly used as a last... 

An improving capability of plastics due to the appearance of new materials, improved qualities with existing types and better processing equipment. 

Minimize or eliminate in-process inventory of hazardous material, including inventory in the processing equipment as well as in tanks. Elimination of intermediate storage tanks will likely require improvements in the reliability of the upstream and downstream operations. 

The nuclear equipment failure rate database has not changed markedly since the RSS and chemical process data contains information for non-chemical process equipment in a more benign environment. Uncertainty in the database results from the statistical sample, heterogeneity, incompleteness, and unrepresentative environment, operation, and maintenance. Some PSA.s use extensive studies of plant-specific data to augment the generic database by Bayesian methods and others do not. No standard guidance is available for when to use which and the improvement in accuracy that is achieved thereby. Improvements in the database and in the treatment of data requires, uhstaiui.il indu.sinal support but it is expensive. 

Equipment and Processes Equipment and supplies should be placed in the cupboard before a procedure commences. Unnecessary equipment should be removed. High-input heat sources within a cupboard will cause convection currents that can disturb the flow and should be avoided if possible. Work should be carried out well within the cupboard, at least 150 mm from the plane of the sash whenever possible. It should not however be placed closer than 50 mm to the lower extract slot of a back baffle. Large pieces of equipment should if possible be raised 25 to 50 mm above the working surface of the cupboard to improve the flow in the cupboard. 

Lipton, S., Reduce Fugitive Emissions Through Improved Process Equipment, Chemical Engineering Progress, vol. 88, no. 10, Oct. 1992, p. 61. 

Carbon black-silica dual phase fillers reduce hysteresis while maintaining or improving abrasion. This system is less expensive as coupling agent requirement is less and produces semicon-ductive product compared to full silica-filler system. Dual phase filler is less abrasive to the processing equipment compared to the usage of silica filler alone, but use of dual phase filler increases cost of compound compared to traditional carbon black. 

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