Analysis of flushing injection performance in a reciprocating plunger slurry pump

Conference · Sun Jan 01 00:00:00 EST 1984

OSTI ID:5525248

One of the major machinery problems encountered during operation of the Exxon Coal Liquefaction Pilot Plant was the relatively short life of the packing in the coal slurry reciprocating plunger pump. The cause of the short packing life was wear created by coal particles. Flushing oil was injected in the throat bushing on a portion of the plunger stroke to limit coal intrusion. To understand the effect of flush oil injection and the effect of the various pump design parameters on the flushing system, a mathematical model was developed by which the fluid dynamics of the throat bushing/plunger annulus could be analyzed. The transient equations of motion were solved numerically to yield the fluid velocity profile and the path of a given coal particle. The pressure gradient was evaluated iteratively from the imposed net flow rate condition which accounted for the flushing and leakage flow rates. Utilizing the model, a comparison was made between suction synchronized flushing and discharge synchronized flushing for various assumed leakage rates. The analysis showed that suction synchronized flushing was superior to discharge synchronized flushing. When the model was applied to ECLP's slurry pumps, it was found that for the pump with a throat bushing clearance length of 2.5 inches, the solids would enter the packing for practically any leakage rate. This was in good agreement with ECLP field experience. For the pump with a throat bushing clearance length of eight inches, the analysis indicated that at leakage rates as high as five gallons per hour solids would still not have entered the packing area. This was also in good agreement with ECLP field experience. Thus, it seems that the analytical model can be used in evaluating various design parameters as well as serving as a design tool for full scale slurry pumps.

• Research Organization: Exxon Research and Engineering Co., Baytown, TX (USA). Baytown Research and Development Div.
• DOE Contract Number: FC05-77ET10069
• OSTI ID: 5525248
• Report Number(s): CONF-840201-1; ON: DE84001649
• Resource Relation: Conference: ASME energy sources technology conference and exhibition, New Orleans, LA, USA, 12 Feb 1984
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
36 MATERIALS SCIENCE
EXXON LIQUEFACTION PROCESS
PUMPS
PACKINGS
SERVICE LIFE
WEAR
DESIGN
MATHEMATICAL MODELS
SLURRIES
COAL LIQUEFACTION
PILOT PLANTS
DISPERSIONS
FUNCTIONAL MODELS
LIQUEFACTION
MIXTURES
SUSPENSIONS
THERMOCHEMICAL PROCESSES
010405* - Coal
Lignite
& Peat- Hydrogenation & Liquefaction
360105 - Metals & Alloys- Corrosion & Erosion