油田采出水中聚合物与阻垢剂协同作用的EQCM评价

EQCM Evaluation of the Synergetic Effect of Polymer and Scale Inhibitor in Oilfield Brine

简介了电化学石英晶体微天平法(EQCM)测定结垢量的原理和所用仪器。在旅大LD10-01油田含钙镁和碳酸氢根离子的结垢性采出水样中,加入不同量膦酸阻垢剂ATMP(0、30、40、60mg/L)和疏水缔含聚合物AP-P4(0,50,100,150mg/L),用EQCM法测定金电极上结垢量随时间(01800s)的变化,结果如下。空白采出水结垢量和结垢量随时间的变化相对不大;ATMP加量为30mg/L时结垢量随时间减小,在更大加量下结垢量随时间急剧增大;AP-P4加量为50mg/L时结垢量最大;同时加入ATMP和AP-P4时结垢量或增大或减小,当二者比例适当时,特别是加入ATMP60mg/L、AP-P450mg/L时,结垢量随时间大幅减小。在含AP-P450mg/L的采出水中分时段加入ATMP,当ATMP总加量为11mg/L时结垢量陡降,继续分批少量加入ATMP时结垢量呈阶梯状缓慢减小。认为AP-P4通过螯合钙离子减轻结垢;ATMP通过螯合和分散作用抑制结垢,并可将生成的垢重新分散在水中。

The principles and instruments for determining scale creation （SC） quantitatively by electrochemical quartz crystal microballance（EQCM） technique are presented concisely. The changes in the amount of scale substances deposited on gold electrode with time up to 1800 sec were investigated in Ca2＋ , Mg2＋ , and HCO3 containing and easily scaling produced water from oil reservoir LD10-01 with phosphinic acid scale inhibitor ATMP added at dosages of 0,30,40 or 60 mg/L and hydrophobically associating polymer AP-P4 added at dosages of 0,50,100 or 150 mg/L. The SC in blank produced water was moderate and varied with time slightly;the SC decreased with time at ATMP dosage of 30 mg/L and increased with time significantly at higher ATMP dosages;the highest SC was observed at AP-P4 dosage of 50 mg/L. Introducing ATMP and AP-P4 in combination led to an enhanced or lessened SC, which was significantly reduced with time at appropriate proportions of ATMP to AP-P4 and, for instance, at dosages of ATMP 60 mg/L and AP-P4 50 mg/L. When ATMP was introduced by fractional doses in different time, the SC in the 50 mg/L AP-P4 dosed produced water was dramatically dropped down after 11 mg ATMP per liter water was introduced and then reduced very slightly and stepwise by every small dose of ATMP. It was argued that polymer AP-P4 lessened the SC through Ca2 ＋ chelation and inhibitor ATMP hindered and prevented the SC through chelation and dispersion and was able to disperse tbe scale deposit in water again.