the application of the polyacrylamide

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2015-03-21 09:35:02

in the oil field industry, well is the basis of oil exploration, drilling quality is one of the key factors of crude oil output. Use of the circulating fluid in rotary drilling is most liquid, say again "mud".

Before the 1920 s, using water as the drilling fluid and in the process of drilling with mudstone debris "natural mud". Later realized the colloid stability good drilling fluid can ensure the safety of drilling and started to develop the drilling fluid chemical treatment agent. Polyacrylamide by 1958 began to be used for drilling fluid, but it led to a significant change in the development of drilling fluid, not only make the drilling speed is greatly increased, and the type of drilling fluid treatment agent from the past natural polymer class to develop in the direction of synthetic polymer type, make the drilling fluid technology has entered the phase of the development of science. Now polyacrylamide polymer in the drilling fluid loss, flocculation, shale inhibition, dilution and plugging plays an important role.

Polymer flocculant can make the drilling fluid in drilling cuttings and inferior soil is in not dispersed state of flocculation, in order to use mechanical solids control equipment will be cleared, better solved the dispersible in the drilling fluid system in drilling fluid drilling cuttings dispersion and accumulation of problems, not only can improve the rate of penetration, and reduced the many complicated situations in the process of drilling, well low to protect the oil and gas layer, reduce the drilling cost.

In the drilling fluid used in polyacrylamide flocculant has not hydrolyzed polyacrylamide and hydrolyzed polyacrylamide. The former belongs to the flocculant, the latter belongs to the selective flocculant. Drilling cuttings and there was a big difference between the electrical nature of soil and the hydration, good soil with negative power is big, cation exchange capacity is big, strong hydration dispersing effect, hydration film thickness. While drilling cuttings with fewer negative electricity, hydration thin film. Nonionic polyacrylamide molecule only polarity amide groups, neither negatively charged, and hydration film and thin, with the high quality the repulsive force between soil and bad soil are smaller. When meet with two kinds of particles, adsorption and bridging can occur. And nonionic polyacrylamide flocculant flocculation effect.

Nonionic polyacrylamide after reaching a certain degree of hydrolysis with higher negative charge density, also has the thickness of hydrated film. When in close proximity to good soil particles, between each other will produce large electrostatic repulsion and hydration film repulsive force, it is difficult to absorb good soil particles; And when in close proximity to cuttings, is easy to generate adsorption, flocculation mass formation, removed from the drilling fluid, have the effect of selective flocculation.