A process-knowledge management approach for assessment and mitigation of drilling risks

In order to consider the uncertainties associated with knowledge, approximate reasoning by type-2 fuzzy logic is combined with relevant numerical simulations (pressure and temperature fields, thermodynamic and kinetic gas hydrate behavior). This combination of knowledge is established by the P-KMS through the construction of individual reasoning blocks and a coherent reasoning lattice. Because expert knowledge (expressed in rules and equations) and standard engineering calculations are combined in a modular form, updating of knowledge, as well as well situation-specific applications of it, are assisted. The P-KMS can be applied in two reasoning modes, either for dynamic process assessment (simulation mode) or static well situation analysis (parameter inference mode). During reasoning, uncertainties employed are monitored constantly in such a way that knowledge gap identification and system performance evaluation is supported. Consequently, it is anticipated that using such a P-KMS approach will lead to (1) increase in well-site security, (2) reduction of overall well costs, and (3) creation of experience in development, implementation and maintenance of a P-KMS for similar problem areas.