The Experimental Study On Disposing Drilling Wastewater In Chemical Method

Drilling waste water which has suspended solid,oil,heavy metal,sulphide,and chloride etc. is produced in drilling. It will pollute environment, especially plants and ground water, if drilling waste water is not disposed but discharged directly.This paper supplies the combinational technics on the base of studying concreting sediment,micro-electroanalysis,catalysis oxidation and active carbon absorption, by studying the effects of various methods on disposing drilling waste water.PFS is used widely and has great effect in concreting sediment experiment. When PFS is used, the best pH ranks from 9 to 10 for most drilling waste water and the best dose which can be confirmed by experiment is varied greatly with different drilling waste water.The lower pH the higher ratio of eliminating COD_Cr in micro-electroanalysis experiment, which can get the best pH is from 1 to 3. The longer the lingering time the higher ratio of eliminating COD_Cr, which can get the best lingering time is from 15 to 25 minutes.At the beginning of catalysis oxidation experiment, the more dose of H₂O₂ the higher ratio of eliminating COD_cr which can get the best dose is from 1 to 4 ml/L, the best disposing time of oxidation is 2.5-3 hours.By studying on the disposing methods of drilling waste water in different sole wells, the major combinational technics for discharging drilling waste water is "pre-discharge—concreting sediment—micro-electroanalysis—catalysis oxidation—active carbon adsorpation" which can be used in discharging drilling waste water. The wells applied with this technics ,for example the No.1 Wangjia Well,the No.25 Qiu Well and the Mo Well, reach the Second Criterion of the Integrated Wastewater Discharge Standard (GB8978-1996).