METHOD FOR DECOMPOSITION OF HYDRO-PARAFFINIC AND ICE PLUGS IN VERTICAL PIPELINE Russian patent published in 2024 - IPC F17D1/05 

FIELD: public utilities.

SUBSTANCE: invention relates to protection of pipelines against freezing and hydrate formation, in particular to a method of decomposition of hydro-paraffinic and ice plugs in a vertical pipeline. Residual pressure is released, a solid chemically active substance in a polymer shell is placed into the open end of the pipeline, immersed in intratubal fluid into pipeline to interval of plug occurrence. Further, an activating agent of higher density than the intratubal fluid is fed into the pipeline, which is lowered into the pipeline to the interval of the solid chemically active substance, where it dissolves its polymer shell and enters into a chemical reaction with it with the release of gas and heat, which melts the plug pushed up the pipeline by the pressure of the reservoir formation together with the reaction products, where everything is collected in a receiving tank for further recycling. Required heating area corresponding to the upper area of the plug is determined. Depending on the initial requirements for the components of the chemical reaction and the properties of the in-tube fluid, the type, shape and size of the solid chemically active substance are selected, time of its immersion under its own weight in the pipeline to the specified heating area is calculated. Introducing it inside a sealed shell from a water-soluble polymer film with a known dissolution time, thickness of which is selected so that the time of its dissolution provides the required delay of the beginning of the chemical reaction until reaching the heating region. Then inter-tube fluid is replaced with another more inert and less dense fluid in relation to the solid chemically active substance, which is further lowered into the pipeline and then an activator agent safe for the reservoir is supplied, the density of which is greater than the density of the inert liquid and less than the density of the solid chemically active substance, which promotes sedimentation of the activating agent to the heating area in the form of a separate layer. Required holding time is observed until the end of the active phase of the chemical reaction occurring within the layer of the activating agent. Cycle of operations is repeated until there is a sharp increase in the intratubal pressure caused by the breakthrough of the plug.

EFFECT: providing greater localization of released heat in the area of the plug and taking into account the conditions of the object.

5 cl, 1 tbl