Initial Experiments on Natural Gas Hydrates

After Hammerschmidt s initial discovery, the American Gas Association commissioned a thorough study of hydrates at the U.S. Bureau of Mines. In an effort spanning World War II, Deaton and Frost (1946) experimentally investigated the formation of hydrates from pure components of methane, ethane, and propane, as well as their mixtures with heavier components in both simulated and real natural gases. 

Predictive method results are still compared to the Deaton and Frost data. It should be remembered, however, that while this study was both painstaking and at the state-of-the-art, the data were of somewhat limited accuracy, particularly the measurements of gas composition. As will be seen in Chapters 4 and 5, small inaccuracies in gas composition can dramatically affect hydrate formation temperatures and pressures. For example, Deaton and Frost were unable to distinguish between normal butane and iso-butane using a Podbielniak distillation column, and so used the sum of the two component mole fractions. Accurate composition measurement techniques such as chromatography did not come into common usage until early in the 1960s. 

Many workers including Hammerschmidt (1939), Deaton and Frost (1946), Bond and Russell (1949), Kobayashi et al. (1951), and Woolfolk (1952) investigated the effects of inhibitors on hydrates. In particular, many chloride salts such as those of calcium, sodium, and potassium, were considered along with methanol and monoethylene glycol. Methanol gradually became one of the 

1934 Hammerschmidt discovers hydrates as pipeline plugs provides Hammerschmidt equation discovers thermodynamic inhibitors 1941 Katz et al. begin -values and gas gravity methods to predict hydrate mixtures 

1946 Deaton and Frost present data summary on hydrates and their prevention 

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