Charts & Tables — Bulk Gas Storage and Supply Systems

Bulk quantities of high-pressure gases and gas mixtures are shipped in tube trailers and stored on site at customer locations. The storage and supply systems for these bulk gases consist of a number of high-pressure seamless steel pressure vessels manifolded together and situated permanently at the customer’s site (see Figure 10 ).

These systems are modular in design and are sized for the customer’s use rate. The systems handle argon, carbon monoxide, compressed air, helium, hydrogen, nitrogen, and oxygen.

Individual pressure vessels measure approximately 22 1/2 feet in length and have a diameter of 24 inches. A permanent manifold connects the vessels selected for the site. The gas discharges to the houseline through a pressure reducing station that automatically controls the pressure. An independent stanchion is provided for filling the vessels from the high-pressure tube trailer. The vessels are filled by the pressure transfill equalization method.

Pressure Vessels
Vessels meet the requirements of the ASME UPV Code, Section VIII and Appendix 22. They have a maximum allowable working pressure of 2,450 psig. Each vessel is equipped with an angle-type shutoff valve and a safety burst disc assembly that will rupture at approximately 3,100 psig. The pressure vessel module is a horizontal row of three vessels mounted between two I-beam frames that provide all necessary support and stabilization. Modular assemblies can be built up to meet almost any range of gas storage requirements.

Pressure Reducing Station
The pressure reducing station is mounted in a weatherproof cabinet, which protects the dual-pressure reducing regulators, gauges, optional low-pressure alarm switches, equalizing valves, safety-relief valves, etc.

Tube Trailer Discharging Stanchion
The L-shaped tube trailer discharging stanchion, fabricated from an aluminum I-beam, supports the flexible pigtail, valves, and piping necessary to discharge product from the tube trailers into the high-pressure storage vessels. This filling apparatus is separated from the control cabinet for safety and convenience.

Fig. 10 Typical Bulk Gas Storage Supply System