Friction and Wear Behavior of Paired Pairs of Ceramics and Metal in High-Pressure Pump of Seawater Desalination

Several kinds of Polytetrafluoroethylene (PTFE) composites are currently being used in reciprocating hydrogen gas compressors as seal material which should articulate against metal counterfaces in pressurized hydrogen gas. Although their friction and wear behavior has large impact on the efficiency and reliability of gas compressors, available information about tribological characteristics of PTFE composites in high pressure hydrogen gas is quite limited. In this study, friction and wear of graphite filled PTFE and bronze filled PTFE were evaluated in the 40 MPa hydrogen gas environment by using a pin-on-disk type apparatus enclosed in a high pressure vessel to supply experimental data for the design of gas compressors in hydrogen fuelling stations. AISI316L austenitic stainless steel disk was used as a sliding counterface. All experiments were conducted under dry condition with the average contact pressure of 1.8 MPa, the sliding speed of 100 mm/s and the gas temperature of 327 K. The friction force exerted between PTFE composites and stainless steel was evaluated by a load cell during the experiment and the wear rate of composites was evaluated from the weight loss of pin specimens. In addition, chemical analysis of the polymer transfer film formed on the disk surface were conducted by using X-ray photoelectron spectrometer. Friction and wear tests were also conducted in 40 MPa helium gas for comparison. Results indicated that bronze filled PTFE was more sensitive to the gas pressure and gas species; it showed good friction and wear behavior in high pressure hydrogen, although friction in high pressure helium became very high. On the other hand, the effects of high pressure gas environment were relatively small for the friction and wear of graphite filled PTFE.

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Numerical and Experimental Investigation of Performance and Reliability in New Reverse Osmosis Seawater Desalination High Pressure Pump

Volume 7B: Fluids Engineering Systems and Technologies ◽

10.1115/imece2013-62598 ◽

2013 ◽

Cited By ~ 1

Author(s):

Xiao-yan Ye ◽

Jing-ning Hu ◽

Jing Wang ◽

Yao-ning Feng ◽

Wei Jiang

Keyword(s):

High Pressure ◽

Centrifugal Pump ◽

Reverse Osmosis ◽

Experimental Results ◽

Seawater Desalination ◽

Axial Thrust ◽

High Pressure Pump ◽

Pressure Pump ◽

Multistage Pump ◽

The Relationship

In order to reduce the investment cost and energy consumption of high pressure pump in Seawater Reverse Osmosis desalination project, a new type of multistage high pressure centrifugal pump with two ends of water-lubricated bearings supporting and axial suction was proposed after analyzing the structural feature of the high pressure pump. The numerical simulation method and mesh quality was improved, the pump performance was predicted and optimized. The relationship of the critical speed and logarithmic decay rate with stage was analyzed, and the relationship between the stage and efficiency of multistage pump was combined to analyze the optimal selection for the impeller stages of multistage pump. The experimental results of axial thrust were used to modify theoretical formula of axial thrust and accurately predicated the axial thrust at different operating conditions. A new balancing device with less leakage fluid, high balancing sensitivity and proper restoring force was designed to improve the reliability of axial thrust balancing device. The experimental results show that the efficiency of the new multistage high pressure centrifugal pump is 83.07% which is increased by 3.07 percents when the design flow rate is 220m3/h, and total Head is 620m. The new multistage high pressure centrifugal pump has been applied in the Chinese Zhoushan seawater desalination project, which runs with high efficiency and stability.

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