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Deposition and precipitation of paraffin wax in pipelines are major problems in the production, transfer, storage, and processing of crude oil. To prevent complete clogging, it is necessary to minimize and remove deposited wax in pipelines and tubing. Significant research has been done addressing the mechanisms of wax formation and its composition. In this review, the status of research and perspectives on the occurrence and characterization of the paraffin wax that forms in crude oil developing wells and pipelines has been critically reviewed. Several approaches for detecting paraffin wax and managing wax formation damage during oil recovery were discussed. This review also highlighted the effects of temperature and crude oil type on wax formation.

The prediction of changes in velocity distribution and channel bed morphology is significant in open channel management and design. This paper implements experimental work to realize and quantify the effect of rigid aquatic bank weeds on vertical velocity profiles and channel bed morphology. In the experimental work, weeds were given a staggered distribution using three distances of 25, 50, and 75 mm, unilaterally and bilaterally, with Froude numbers ranging from 0.11 to 0.30, achieving 168 scenarios. Results for the tested weed cases showed that the average velocity was directly proportional to the weed density and approached the Froude number. By comparing the smooth and weeded velocities, it was found that the velocity inside the infested reach was close to the downstream velocity and exceeded the upstream velocity by about 10% and 41%, respectively. Scour depths along the centerline of the vegetated reach for the bilateral weeds were higher by 11% to 33% than those for the unilateral weeds. The maximum observed depth of the scour holes along the smooth bank was about 30% to 60% of the maximum scour depth at the middle line. Finally, to quantify the results, multiple regression analysis was performed to develop empirical equations to assist in the water management process.