Polyvinyl chloride balanced process

During the 1970s Jersey Standard s chemical product portfolio had been reduced to resemble that in 1960. Its primary chemical business remained the production of ethylene, basic polymers (including LDPE, linear low-density polyethylene (LLDPE) using the Unipol process, licensed from Union Carbide, PP, and polyvinyl chloride (PVC), plasticizers (particularly for vinyl production), elastomers, and synthetic rubbers. Profits returned. The 1974 balance sheet listed earnings of 456 million on revenue of 3.3 billion, making Exxon Chemical one of the five most profitable chemical companies worldwide. 

Many researches adopted one of the aforanentioned approaches and modified it to include various aspects of the pneumatic drying process. Andrieu and Bressat [16] presented a simple model for pneumatic drying of polyvinyl chloride (PVC), particles. Their model was based on elementary momentum, heat and mass transfer between the fluid and the particles. In order to simplify their model, they assumed that the flow is unidirectional, the relative velocity is a function of the buoyancy and drag forces, solid temperature is uniform and equal to the evaporation temperature, and that evaporation of free water occurs in a constant rate period. Based on their simplifying assumptions, six balance equations were written for six unknowns, namely, relative velocity, air humidity, solid moisture content, equilibrium humidity, and both solid and fluid temperatures. The model was then solved numerically, and satisfactory agreanent with their experimental results was obtained. A similar model was presented by Tanthapanichakoon and Srivotanai [24]. Their model was solved numerically and compared with their experimental data. Their comparison between the experimental data and their model predictions showed large scattering for the gas temperature and absolute humidity. However, their comparisons for the solid temperature and the water content were failed. 

Pasa-Jell (www.bergdahl.com/PasaJell.htm) is a proprietary chemical marketed by Semco Division, Products Research and Chemical Corp., Glendale, CA. This formulation is available either as a thixotropic paste suitable for brush application or as an immersion solution for tank treatment. Pasa-Jell 107 is a blend of mineral acids, activators, and inhibitors, thickened using inorganic agents, to permit application in localized areas. The approximate chemical constituents are 40% nitric acid, 10% combined fluorides, 10% chromic acid, and 1% couplers, and the balance is water. The immersion process requires nonmetallic tanks made of polyvinyl chloride (PVC), polyethylene, or polypropylene. A recommended mixture uses 1 1 dilution for 12 min. With the thixotropic Pasa-Jell paste, a reaction time of 10—15 min assures durable bonds. ... 

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