High pressure vessel

High pressures are required for many commercial chemical processes. For example, the synthesis of ammonia is carried out at reactor pressures of up to 1000 bar, and high-density polyethylene processes operate up to 1500 bar. 

---

For the gun steels often used in the constmction of high pressure vessels, the latter criterion is favored (9) according to which, Hence... 

In 1979 because neither Division of Section VIII was suited to the design of high pressure vessels, the ASME Board on Pressure Technology,... 

Codes Standards approved the estabUshment of a Special Working Group for high pressure vessels under the ASME Subcommittee on Pressure Vessels (Section VIII). The main design criteria, which are likely to be incorporated in a new Division of Section VIII, have been set out (149). 

Reductive alkylations and aminations requite pressure-rated reaction vessels and hiUy contained and blanketed support equipment. Nitrile hydrogenations are similar in thein requirements. Arylamine hydrogenations have historically required very high pressure vessel materials of constmction. A nominal breakpoint of 8 MPa (- 1200 psi) requites yet heavier wall constmction and correspondingly more expensive hydrogen pressurization. Heat transfer must be adequate, for the heat of reaction in arylamine ring reduction is - 50 kJ/mol (12 kcal/mol) (59). Solvents employed to maintain catalyst activity and improve heat-transfer efficiency reduce effective hydrogen partial pressures and requite fractionation from product and recycle to prove cost-effective. 

AH commercial processes (8—10) use either NaOH (4) or Na2C02 (5) as solvent systems. The dissolving mechanism is similar ia both solvents because hydrolyzes to OH . Sodium salts are required because insoluble sodium iron sHicates form on the steel waHs of the high pressure vessels... 

Close proximity of hazardous process. High pressure vessels which may fail explosively. 

The vent sizing package (VSP) was developed by Fauskes Associates, Inc. The VSP and its latest version VSP2 employ the low thermal mass test cell stainless steel 304 and Hastelloy test cell with a volume of 120 ml contained in a 4-1, high-pressure vessel as shown in Figure 12-13. The typical ([t-factor is 1.05-1.08 for a test cell wall thickness of 0.127-0.178 mm. Measurements consist of sample temperature Tj and pressure Pj, and external guard temperature Tj and... 

Many companies require that all their pressure essels lie constructed in accordance with Division 2 because of the more exacting standards. Others find that they can purchase less expensive vessels by allowing manufacturers the choice of either Division 1 or Division 2. Normally, manufacturers will choose Division 1 for low -prcssure vessels and Division 2 for high-pressure vessels. 

Vessel drain systems can be very dangerous and deserve careful attention. There is a tendency to connect high-pressure vessels with low-pressure vessels through the drain system. If a drain is inadvertently left open, pressure can communicate through the drain system from the high-pressure vessel to the low-pressure vessel. If this is the case, the low pressure vessel relief valve must be sized for this potential gas blowhy condition. 

FIGURE 9.14 One of the high-pressure vessels used for the catalytic synthesis of ammonia. The vessel must be able to withstand internal pressures of greater than 250 atm. 

Maleation of iPP was carried out in a high-pressure vessel. After a desired time interval, the vessel was quenched with running cold water to terminate the reaction. Samples were taken out and then purified for subsequent determination of the grafting degree [5]. 

Applications Sample preparation capabilities for AAS, ICP, ICP-MS are greatly improved by advanced microwave technology with high-pressure vessels (up to 300 °C and 1500 psi), which provide ... 

Fryer, D. M. and Harvey, J. F. (1997) High Pressure Vessels (Kluwer). 

Fryer DM., Harvey J.F., 1998. High pressure Vessels, Chapman Hall, London. 

High pressure valves, manual, 13 415 High pressure vessel suppliers, 13 412 High production volume (HPV) chemicals, 24 186... 

Methoxy-2-Naphthol. A mixture of 10 g of 6-bromo-2-methoxynaphalene, 0.5 g of copper bronze, 8.5 g of NaOH, and 175 cc of water are shaken in a suitable high pressure vessel at 200° for 75 minute. Cool, dilute with a little water, filter copper off, and acidify with coned HCl acid. Collect the resulting product, wash with water and dry in air. Recrystallize the resulting crude product with dilute ethanol to get a little over 5 g. 

---