Synthesis and application of ethylene diamine tetra methytene phosphonate as oil well cement retarder

Key words:  retarder  thickening time  compatibility  compressive strength  oil well cement additives

Abstract:

The thickening time and resistance to temperature of cement slurry usually fail to meet the request of field working at high temperature. So ethylene diamine tetra methylene phosphonate (EDTMP) was synthesized as an oil well cement retarder. And the resistance to temperature property, the high temperature retardation, salt-resisting performance, compatibility of EDTMP and the effects of those properties on compressive strength of cement were evaluated. And the performance of EDTMP was compared with other retarders. EDTMP retarded mechanism was also analyzed, and the field application was carried out. The results demonstrate that EDTMP can be used at 170 T and shows advantages such as little dosage, excellent retardant, controllable thickening time，an ideal thickening curve, excellent salt-resisting performance, no effect on compressive strength and good compatibility with other additives. The application results show that the retarder can be applied to slat bed , long cement point and high temperature and its effect is remarkable.