The basic reason for wax formation in oil wells is that the crude oil produced by oil wells contains wax. There are two processes for oil well wax formation. First, the wax is precipitated from the crude oil, and then aggregates and adheres to the pipe wall. The wax that was originally dissolved in crude oil was condensed out during the mining process due to the decline in the ability of crude oil to dissolve wax. When the composition, temperature, and pressure of the crude oil change, so that its dissolving ability decreases, a part of the wax is precipitated from the crude oil. Our company provides API sucker rod.
Factors of paraffin precipitation in oil wells
Composition and temperature of crude oil
Under the same temperature conditions, the solubility of light oil to wax is greater than that of heavy oil. The more light components contained in crude oil, the lower the crystallization temperature of the wax, that is, the wax is not easy to precipitate, and the wax in the dissolved state is maintained. The greater the amount. The amount of wax dissolved in any petroleum decreases with decreasing temperature. Therefore, a part of the amount of wax dissolved at high temperature will be condensed out when the temperature drops. At the same wax content, the wax crystallization temperature of heavy oil is higher than the crystallization temperature of light oil. It can be seen that petroleum with few light components has a tendency to condense out the wax.
2. Pressure and dissolved gas
Under the condition that the pressure is higher than the saturation pressure, the crude oil will not be degassed when the pressure is reduced, and the initial crystallization temperature of the wax decreases with the decrease of the pressure. Under the conditions of pressure and saturation pressure, the gas in the oil is continuously separated out when the pressure is reduced, which reduces the ability to dissolve the wax. Therefore, the initial crystallization temperature is increased. This is because the light component gas methane is separated in the early stage; ethane, etc., and the heavy component gases such as butane are separated in the later stage, the latter has a greater influence on the dissolving ability of the wax, thus significantly increasing the crystallization temperature. In addition, the dissolved gas is also subjected to expansion and heat absorption when it is separated from the oil, which promotes the reduction of the temperature of the oil flow and is beneficial to the precipitation of wax crystals.
Above information is provided by cheap Coupling manufacturer China.
