A Layered reservoir system with a constant pressure bottom boundary has immense potential to produce oil and gas, using horizontal wells may further increase productivity because it offers a larger surface area for fluid withdrawal. Test analysis in this system is tedious, time consuming and interpretation may be confusing or erroneous. Hence an efficient algorithm is needed to generate accurate pressure response of the wells to facilitate quick and easy analysis and prediction. This paper presents an interactive computer program that computes the dimensionless pressure and dimensionless pressure derivatives of horizontal wells in a two layered reservoir system with a constant pressure boundary. Program's codes and structure of the reservoir model solution were written utilising the exponential integral solution, Gauss Laguerre and Gauss Lagrange numerical methods. The program has features that gave visual interpretation (graphical user interfaces (GUI)) as it computes pressure and derivative values when the interface between the layers is either permeable (crossflow reservoir) or impermeable (no crossflow reservoir). Examples illustrating its use in model identification and well test analysis of layered system with constant pressure boundary are also included in this work. Hence it will serve as a good learning tool because it is user friendly, fast and results have acceptable level of accuracy.

Enhanced oil recovery (EOR) is important to the petroleum industry mostly because it is used to improve oil recovery. Miscible gas flooding, a type of EOR process that is proven and economically viable can significantly increase oil recovery from reservoirs. In this study, the minimum miscibility pressure (MMP) in gas floods for different gases were computed using empirical correlations (Glaso correlation for hydrocarbon gas injection, Emera, Yuan et al and Glaso correlation for pure carbon dioxide gas injection, Sebastin and Yuan correlation for impure carbon dioxide correlations and Glaso, Firoozabadi and Aziz correlations for nitrogen gas injection). An efficient computer program was developed using visual basic programing language. Employing its highly versatile features, friendly graphical user interface (GUI) forms were designed and robust codes were developed. Validation was done for the program and results showed that the software which was developed had acceptable level of accuracy, was fast and effective. The study provides a new and cost effective way of checking for MMP which will enhance the process of screening gas flooding processes for the reservoir.