Daniudi gas field is a typical tight sandstone gas reservoir.The remaining non-produced reserves are charac-terized by poor quality

thin net pay thickness and poor vertical superimposition of pay zones.For these types of reservoirs

it is critical to optimize technical policy of horizontal well development and perfect gas reservoir engineering technique series.Empirical formula

dynamic performance analysis

numerical simulation and economic evaluation were used to optimize technical policies including productivity evaluation

single well design

well pattern and spacing and other aspects regarding horizontal well development.We defined the principles of strata series classification and selected mutiple methods of productivity evaluation.The study shows that the gas production should be proportionally 1/5~1/3 of open-flow capacity

and the lateral should be 1 000~1 200 meter long.The well trajectory should be perpendicular to the maximum principal stress and be located as close as possible to the center part of the reservoir.The fracturing design should refer to the quantitative calculation model.The well pattern should be staggered line-drive with a well spacing of 800~1 200 meter.The abandonment formation pressure should be 8 MPa.All these factors would finally yield a recovery factor of 40%.The optimized parameters have been applied to the Daniudi gas field

and they provided a strong technical foundation for the successful implementation of the development plan in this tight sandstone gas reservoir.