Pressure_Vessels_Specifications.docx

R17PS00702

Pressure Vessels Specificatons Background The Bureau of Reclamation’s (Reclamation) Yuma Desalting Plant (YDP) is 73-million Gallon per day (MGD) rated brackish water desalination facility utilizing Reverse Osmosis (RO) technology. When the facility was designed in the 1980’s the market for RO membrane elements had yet to converge on a standard element size, and the plant was designed to operate with 12-in and 8.5-in diameter elements. Since that time the market has converged on standard sizes of 8-in and 4-in diameter elements. This has resulted in limited availability of 12-in and 8.5-in elements. YDP has standardized the pressure vessels (PV) to 8-in diameter in accordance with products available in the market.

The YDP currently has 720 of the 8.5-in diameter PVs installed. Due to the availability of 8-in membrane elements with the same active membrane area as the 8.5-in, the 8.5-in PVs will be replaced with 8-in PVs on a one-to-one basis. The 1,080 12-in PVs will be replaced with 1,890 8-in PVs. This increase in the number of pressure vessels, and therefore connections, will require the purchase of new couplings; IPS grooved couplings were chosen for interoperability with the existing connections.

The typical operating feed pressure of the system is 350-450 psi. The piping and pumps are designed for a maximum feed pressure of 500 psi. In order to ensure safe operation and maintain a 500 psi design pressure the supplied PVs must be designed for an operating pressure of at least 500 psi.

The different dimensions of the new PVs compared to the previous, will necessitate new feed, concentrate and permeate piping connections. For its corrosion resistance 316L-series Stainless Steel was selected as the piping material.

Requirement Reference Standards American Society of Mechanical Engineers (ASME) ASME Boiler and Pressure Vessel Code (BPVC) Section X – Fiber-Reinforced Plastic Pressure Vessels ASME B31.3 Process Piping ASTM A312-16a Standard Specification for Seamless, Welded, and Heavily Cold Worked Austenitic Stainless Steel Pipes ASTM A351-16 Castings, Austenitic, for Pressure-Containing Parts ASTM A778-16 Seamless and Welded Austenitic Stainless Steel Tubing for General Service ASTM A999-16 General Requirements for Alloy and Stainless Steel Pipe ASTM A1016-14 General Requirements for Ferritic Alloy Steel, Austenitic Alloy Steel, and Stainless Steel Tubes ASTM A890-13 Castings, Iron-Chromium-Nickel-Molybdenum Corrosion-Resistant, Duplex (Austenitic/Ferritic) for General Application AWWA C227-11 Bolted, Split-Sleeve Restrained and Nonrestrained Couplings for Plain-End Pipe

Requirement Specification

a. Sized for seven (7) standard 8x40-inch elements

b. Rated to at least 600 psi

c. 1.5-inch NPS feed & concentrate ports, CF3M (ASTM A351) or 316L (ASTM A312) stainless steel, IPS grooved connection

d. 1.25-inch NPS Permeate port on feed end, CF3M (ASTM A351) Stainless steel, IPS grooved connection

e. 1-inch Permeate port on concentrate end, Noryl, FNPT connection

f. Membrane element adapter (element model to be determined after the contract is awarded)

g. Fiberglass shell

h. UV transmittance <0.05%

i. Designed for use with brackish feed water (3,500 TDS) and resistant to 1-ppm of continuous free chlorine exposure

j. Max operating temperature 120°F, Min operating temperature 32°F

k. Saddles, supports, and straps not required

l. Include all seals, gaskets, O-rings, retaining rings, thrust rings/cones, nuts, bolts, and miscellaneous items.

m. Minimum 5-year warranty.

n. ASME Section X Code stamped

a. Standard: ASTM A312

b. Type: Welded Unannealed

c. Straight Seam

d. UNS Grade: S31603

e. Size: 1½-inch NPS Schedule 40S (ANSI B36.19)

f. Single random lengths (18 to 22 feet)

g. Hydrostatic tested in accordance with ASTM A999

a. Sized for seven (7) standard 8x40-inch elements

b. Rated to at least 600 psi

c. Four coplanar feed/concentrate side ports (two on feed end and two on concentrate end)

d. 2-inch NPS feed & concentrate ports, CF3M (ASTM A351) or 316L (ASTM A312) stainless steel, IPS grooved connection

e. 1-inch Permeate ports on feed & concentrate ends, Noryl, FNPT connection

f. Membrane element adapter to be determined after the contract is awarded

g. Fiberglass shell

h. UV transmittance <0.05%

i. Designed for use with brackish feed water (3,500 TDS) and resistant to 1-ppm of continuous free chlorine exposure

j. Max operating temperature 120°F, Min operating temperature 32°F

k. Include Saddles, supports, and straps

l. Include all seals, gaskets, O-rings, retaining rings, thrust rings/cones, plates, retainers, nuts, bolts, and miscellaneous items

m. Minimum 5-year warranty

n. ASME Section X Code stamped

a. Housing Material: ASTM A351 CF8M or ASTM A890 CE8MN

b. Gasket material: EPDM, ANSI/NSF 61 approved for cold and hot potable water systems

c. Bolt material: ASTM F593, TP 316

d. Nut material: ASME/ANSI B18.22, Type 651 silicon bronze

e. Pressure Rating: at least 600 psi on rolled grooves and ANSI B36.19 2-inch NPS Schedule 40S pipe