Abstract: Water production from oil wells is a common event which augment the cost of producing processes and may decrease the efficiency of the recovery of reserves. We will deal with the reason of this production of water, namely, coning. Several approaches have been exhibited to overcome this problem, whatever before or after the taking place of water coning. The critical rate (the maximum production rate without producing water) is the widely method used to overcome this problem before it occurring. The objective of this research is to present a method to calculate critical rate, breakthrough time, and WOR (water oil ratio) after breakthrough in horizontal well. A 3-D numerical simulator model was used to perform a comprehensive sensitivity analysis of water coning process. From this analysis, an empirical coning correlation was developed based on regression analysis. The format of the correlation is similar to Addington's gas-coning and Yang’s water coning correlations. The correlations developed in this paper provides a hand calculation fashion of coning prediction for horizontal wells. The correlation was tested and found to be reliable and accurate in predicting critical rate, breakthrough time and WOR, inside the correlation parameter range.
Keywords: Water coning; Critical rate; horizontal well; Water production.