Method for processing waste slurry

Abstract

The invention discloses a method for processing waste slurry, comprising the following steps: firstly, a sand-stone segregation apparatus separates, washes and discharges the drill cuttings sand and stone in the slurry; the pH value of the remaining slurry is adjusted and the COD value thereof is reduced; the solid and the liquid are separated from each other in a way of composite flocculating; water solution is separated out from the solid in a way of mechanical drying; the dried solid isolate meets the relative standard so as to be processed in a way of stacking or land filling; finally the separated water solution is processed in a way of filtration and reverse osmosis so as to obtain fresh water which is recycled or discharged on the spot. The method can be carried out by matching with an unit device and make continuously impending treatment of the well drilling waste slurry during drilling synchronously with normal well drilling production so as to continuously process the efflux hazardous waste to meet the discharge standard with out loading in the well drilling of oil-gas field, change the prior traditional whole efflux curingprocess mode, and fills the gap of an environmentally friendly governing field of oil drilling in the domestic.

Description

technical field [0001] The invention relates to the treatment of hazardous waste discharged during the drilling process of oil and gas fields, in particular to a harmless and up-to-standard treatment method for waste drilling mud. Background technique [0002] During the drilling process of oil and gas wells, the drilling fluid mixed with complex chemicals undergoes physical changes at high temperature and high pressure thousands of meters underground, and carries a large amount of cuttings and sandstones from the ground, which are discharged from the wellhead and become concentrated Slurry hazardous waste. For a long time, my country has adopted a method of collecting hazardous wastes (waste mud, effluent mud, and drill cuttings) from drilling in oil and gas fields in a waste mud pool dug near the drilling rig, and then solidifying and burying them. This method not only occupies a large amount of land resources (each well occupies an area of ​​2-5 mu), but also has high co...

AI Technical Summary

Problems solved by technology

This method not only occupies a large amount of land resources (each well occupies an area of ​​2-5 mu), but also has high construction costs and processing costs, and actually does not treat hazardous wastes-drilling waste mud, effluent mud and cuttings ( Included in the 2008 Solid Hazardous Waste List of the Ministry of Environmental Protection) for harmless and up-to-standard treatment, that is, its pollution source always exists, either causing direct pollution to the environment due to spillage or leakage, or becoming a pollution to the natural environment, groundwater sources and ecology Hidden danger

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