Plant PHA

It is difficult, at present, to get a clear idea of the efficiency of the various plant PHA extraction protocols. In a patent application by Metabolix [74], it was reported that the efficiency of purifying poly(3HB) which was mixed with ground rapeseed was approximately 24% when using an oil-extraction step with hexane followed by refluxing in chloroform for 22 h and evaporating the chloroform to recover poly(3HB). The co-extraction of oil with a PHA contain-... 

Review of the original plant PHA and all plant modifications from the plant start-up... 

Monsanto, USA PHB, PHBV Plant PHA production 1990s Raw materials... 

Plant PHA team approves all devices used in SIS service Low complexity devices with plant familiarity SIL claim limit with documented source... 

PHAs are performed primarily to reduce losses resulting from incidents that can injure plant personnel or the public, or damage or destroy buildings, equipment, and material. There are other less measurable losses that occur after incidents. Companies reputations, the industry s reputation and the effect on customers and the public are all at stake. 

Working with a Process Hazards Analysis (PHA) team was particularly rewarding. The plant operators on the team pointed out items that they had considered safety problems for years, but that hadn t been fully addressed until the PHA team was formed. We used the What if analysis method. Many methods are available for PHA. 

Another proeess where the employer might eonsider using a generie type of PHA is a gas plant. Often these plants are simply moved from site to site, and therefore, a generie PHA may be used for these movable plants. Also, when an employer has several similar size gas plants and no sour gas is being proeessed at the site, a generie PHA is feasible as long as the variations of the individual sites are aeeounted for in the PHA. 

PHA is required for new systems that are designed and construction for the Department of Defense (MrL-STD-882A) it is useful for initial PSA of any system (Lambert, 1975). A PHA is a tabular listing of possible accident initiators, the parts of the plant that could be affected and possible effects of an accident. Because a PHA is performed before a PSA,... 

As indicaled above, the PHA may ser c as a precursor lo further hazard analyses. It is included in lliis chapter because it can pro ide a cost effective, early-on plant method for hazard identification. As its title indicates, the PHA is really intended for use only in the preliminary phase of plant development for cases where past e.spcriencc provides little or no insight into any potential safety problems, e g., a new plant with a new process. 

One illustrative example is presented in tliis final cliapter. It lias been adopted from tlie outstanding work of Kavianaian et al. and is concerned with an ethylene production plant. Tlie solution involves a prcliminaiy hazards analysis (PHA) and tlie development of a fault tree for tlie process. 

Table 21.7.2 smnmarizes die results of applicadon of a preliminary liazard analysis (PHA) to the pyrolysis section of an ediylene plant. The major liazard to the persomiel and plant is die fire or explosion hazard of die gases used or produced in die process. 

Finally, the synthesis of biodegradable poly(hydroxyalkanoic acids) (PHA) by bacteria or genetically modified plants should be mentioned. The microbiology, biochemistry, and genetics of PHA biosynthesis have been reviewed by several authors52,105,405 407 and are beyond the scope of this chapter. 

Purification of industrial oils, kerosene/jet fuel, lubricating oils Mono- dicumyldiphenylamine Mono- dioctyldiphenylamine Dimer fatty acids Purification of xylenes Improvement of bromine number of recycle cumene in phenol plants Improvement of bromine number of recycle ethylbenzene in styrene plants based on liquid pha.se oxidation Alkylation of xylenes with diisobutylenes to mono-/ rr-butyI derivatives Phenyl xylyl ethane... 

E. A. Robleto, A. J. Scupham, and E. W. Triplett, Trifolitoxin production in Rhizohium eili strain CE3, increases competitiveness for rhizosphere colonization and root nodulation of pha.seolus vulgaris in soil. Mol. Plant Microbe Interact. 10 228-233 (1997). 

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