Hydrates in Petroleum Production - Deposition Characteristics

Hydrate plugging of pipelines and equipment during petroleum production is associated with high costs. Traditional methods for hydrate avoidance are quite conservative, leading to inefficient use of capital and limitations in new developments. It has been shown, however, that even when operating within the thermodynamic conditions for stable hydrates, a hydrate plug is not always formed. In recent years, new knowledge on when it is safe to operate in the hydrate domain has introduced risk management as an alternative to traditional hydrate strategies. Risk management means that instead of attempting to avoid hydrate formation altogether, operating procedures may become more effective, cheaper and less hazardous through assessment of the actual plug risk i n each case. Such strategies must rely on in-depth knowledge of hydrate formation, growth and deposition mechanisms. This project proposal aims at developing a fundamental understanding of hydrate deposition in transport of petroleum fluids by relating m acroscopic properties to small scale behavior. Field studies are hard to compare due to the variety of parameters that influence the behavior of a well-stream. Hence, comparable experimental conditions and simple systems are required. Experimental testing of hydrate deposition at different physical conditions will be performed. The parameters will be systematically varied under controlled conditions in adequate equipment, and the results will be interpreted in terms of fundamental physical and chemical pr inciples. The project will benefit from interaction with the ongoing KMB project HYPERION undertaken by some of the proposers, which focuses on understanding the inherent mitigation effects of oil on gas hydrate behavior. By this project, SINTEF, the Univ ersity of Bergen, Chevron and Hydro aims to progress the knowledge base, awareness and ability to handle and solve hydrate plugging problems beyond its current state.