Research On Fouling And Treatment Countermeasures Of Injection Wells In Nanpu Oilfield

In the process of oilfield water injection development, the ion chemistry balance between the original formation water and the reservoir minerals is destroyed when the water is injected into the water and not compatible with the formation water. In the process of breaking the old balance of the establishment of a new balance, as long as more than two kinds of fluid encountered incompatibility exists or in the process of flowing chemical group with pressure and temperature changes or the fluid imbalance, there are scaling and inevitable to the reservoir, wellbore and surface pipeline and production of oil and water wells equipment damage, affecting the normal production of the oil, and even bring great economic losses. Therefore, understanding the scaling tendency of oil, to find out the scaling law, and according to the present situation of fouling scale prevention and removal measures are particularly important.Research status quo of fouling and scaling history in Nanpu oilfield, according to the site to provide water data and the scale analysis, draw oil water mainly containing Ca2+, Mg2+, HCO32- and SO42- ions into the scale, easy to produce a lot of calcium and magnesium scale. Based on the Scalechem scaling prediction software, the scaling types and scaling factors were studied, and the experimental study was carried out according to the prediction results. The research results show that the formation scaling scale is of calcium carbonate scale, the mixing ratio and the pH value of the injection water and the NP118 well formation water has a great influence on the scaling.According to the main scale, the experimental study on the optimization of scale inhibitor is carried out. The experimental results show that the inhibition effect of scale inhibitor TH-607B is better, and the scale inhibition rate is more than 85%. Experimental results show that, with the increase of scale inhibitor concentration, scale inhibition is the first to increase and then decrease, the optimal concentration is 120mg/. With the increase of temperature, the scale of scale inhibition increases first and then decreases. With the increase of pressure, the scale inhibition rate increases slightly, but the increase is not very large. With the increase of pH, the scale inhibition rate showed a decreasing trend, and the most suitable pH was 7.According to the above experimental results, obtained the best inhibitor and the optimal concentration in Nanpu oilfield, combined with the anti scaling measures of the existing field, the Nanpu oilfield scaling problem has been under control.