32results about How to "Avoid clogging accidents" patented technology

The invention discloses a method for exploiting coal bed methane in collapse old goafs and lower coal beds in a combined manner. The method includes surveying mines, constructing horizontal wells from the ground to intermediate rock strata of the old goafs and the lower coal beds, carrying out fracturing and extracting the coal bed methane; circularly carrying out extraction stopping-decompression extraction procedures when the unit-time coal bed methane extraction quantities are reduced and reach 20%-40% of Q<1>, and continuing to extract the coal bed methane; carrying out secondary fracturing when the extraction quantities are lower than 10% of the Q<1>, constructing drainage straight wells and arranging equipment to drain the coal bed methane; carrying out carbon dioxide gas displacement when the extraction quantities are reduced and are lower than 20% of Q<2>, and draining the coal bed methane; carrying out supercritical carbon dioxide displacement when the extraction quantities are reduced again and are lower than 20% of the Q<2>, draining the coal bed methane until the extraction quantities are reduced and reach 10% of the Q<2>, and stopping extracting the coal bed methane. The method has the advantages that coal bed methane resources in the old goafs and the adjacent coal beds can be extracted together by the aid of the method, accordingly, the cost can be saved, and the coal bed methane resources can be extracted to the greatest extent.

The invention discloses an extraction method for mining formed composite old mined-out area coalbed methane through a lower caving method. The method includes the steps that coalbed methane extraction is conducted by constructing a horizontal well at the position 1-5 meters above a lower goaf fissure zone; when the extraction amount of the coalbed methane is dropped to 10-20% of Q, segmented crushing is conducted, extraction is conducted on the goaf coalbed methane again, and when the extraction amount of the coalbed methane is dropped to 10-20% of Q again, supercritical carbon dioxide is injected to drive and replace the coalbed methane; extraction is conducted again till the extraction amount is dropped to 6 m<3> / min, and extraction is stopped. By means of the method, the problems that when a ground vertical drilling well is separately used to conduct extraction on a goaf originally, the effective contact area between the extraction drilling well and a goaf reservoir is small, and the extraction range is limited are solved; while the coalbed methane of the goaf on the lower layer is extracted, the coalbed methane resource close to the upper portion of the goaf is also extracted, and cost is saved; meanwhile, the horizontal well is located in the rock stratum, and therefore shaft collapse and blocking of the drilling well in a coal seam are avoided.

The invention relates to a foundation base of an air-film building, which includes a platform plate and a decompression steel foot. The lower part of the platform plate is buckled and connected with steel block teeth, and the lower part of the steel block teeth is provided with a rolled steel plate, and The inner side of the rolled steel plate is pasted with a rubber patch, the decompression steel foot is arranged under the rolled steel plate, and the inner side of the decompression steel foot is connected with a pin bar, and the two ends of the pin bar are provided with hexagonal For the rivet, an extended rubber pad is provided under the decompression steel foot, and a concrete layer is pasted under the expanded rubber pad, and a steel bar is installed inside the concrete layer, and a ligature wire is provided outside the steel bar. The beneficial effects of the present invention are: the base of the gas film building is equipped with an aluminum alloy plate, the adhesive glue can tightly adhere the aluminum alloy plate to form a honeycomb structure, and a supporting keel is arranged inside the aluminum alloy plate Support it, so that it can not only strengthen the strength of the equipment, but also reduce the quality.