Studies On The Analysis Method And Degrading Technology Of Carboxymethyl Cellulose In The Drilling Waste Fluids

Carboxymethyl cellulose(CMC)has good performance that based on thickening,dispersing and water-keeping,it is widely applied in the mass industry department,especially in driling,cementing and fracturing.CMC is used widely as treating agent in the petroleum industry.First,it brings vast convenience to the petroleum driling and exploitation to some extent;Second,CMC discharged to the environment leads to surface water pollution,and even pollutes soil and groundwater,and causes damage to animals,plants and human health directly or indirectly.Developping pollution monitoring and treatment research to CMC plays an important role in environmental significance.Author collected drilling fluids from 162#,164#,528# and etc.5 well sites in northern Shanxi Chang-Qing oil field in Augest 2007.Basing on the physicochemical properties of drilling fluids, establishing a new method that determinates the content of CMC.At the same time,putting forward to two effectively degrade CMC methods.The main research conclusions are as followed:(1)Choosing the drilling fluids in the 5 well field which is in the North area of ChangQing oilfield to carry on the pollution characteristic analysis.35 physicochemical indexs and contamination indexs had been determined in the drilling fluids.The drilling fluids'ingredient is clay,PAM,CMC.CODCr,mineraloils,NH⁴⁺,Cr,Cd,Pb,As,pH,chromaticity and so on exceed standard in the drilling fluids,CODsuperstandard is very large,and its multiple are 7.08-45.38.The other over-standard parameters'superstandard multiple is not big.(2)Establishing a new method with the spectrophotometric determination of trace CMC.In weak acid or weak basic medium,sodium carboxymethyl cellulose(CMC),owing to dissociation of its carboxyl groups to exist as big negative ion,formed ion association complexes with the quaternary ammonium salt positive ion through electrostatic and hydrophobic interaction.While the absorption spectrum changes and Triton-X100 can increase the sensitive function of the system.A significant absorption of absorbance is 240nm with CMC which is observed respectively.The reactions show very high sensitivities with the absorptivities of 6.73×106 L·mol-1·cm-l.This method is simple and rapid,and can be applied for the spectrophotometric determination of trace CMC in the centrifugate of the drilling mud.(3)This article ppoposes a degeneration method of CMC in waste drilling fluid by UV/ Fenton—TiO₂ synergetic degradation.Inspecting the influence of thecatalyst dosage,the pH value and Fenton reagent dosage and so on to the response.The result indicates that the degeneration effect of UV/Fenton-TiO₂ synergetic degeneration method is remarkable:Under the ultraviolet light illumination,30%H₂O₂ dosage is the 4.00mL,FeSO₄·7H₂O dosage is 0.3794g,TiO₂ catalyst is 0.50g,pH=5,degrading CMC solution only needs 15min completely,The degeneration efficiency is 99.90%.its concentration is 60.0mg/L and the volume is 2L.This degeneration efficiency of the method is high,the time is short,the expense is low and the experiment operation is easy and feasible.(4)Further trails ppoposes a degeneration method of CMC in waste drilling fluid by microwave/coagulation synergetic degradation.Inspecting the influence of coagulation dosage,the pH value and reaction time and so on to the response.The result indicates:under the same condition(polyaluminium chloride dosage is 120mg/L,pH=4,the time is 6 min,the power is 700W), degrading CMC solution whose concentration is 60.0mg/L and the volume is 2L.The degeneration efficiency is 99.90%.