Study on dynamic production optimization for water produced gas wells in Daniudi low permeability gas reservoirs

Applying traditional production allocation method to water produced gas wells in Daniudi field, characterized with low pressure, low permeability, and low production, can not fully use liquid removing potential, leading to large accumulative production of deliquification and finally low ultimate recovery. The paper theoretically set up a dynamic prediction model for water produced gas well, by nodal system analysis, based on material balance principle, well productivity and flowing pressure and temperature drop theories. The model can predict reservoir pressure, bottom hole flowing pressure, wellhead flowing pressure, production rate, and recovery varying with time. A new production allocation method was proposed, considering continues liquid removing theory. The allocated production dynamically decreases with time, and is always larger than critical gas rate for liquid removal, which avoids lower ultimate recovery. Daniudi DK3 well was used as an example to be compared with published method, and the results show that the new method can reduce the accumulative production of deliquification, and enhance ultimate recovery..