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This paper discusses the optimization and control of the one dimensional (1-D) packed bed model of underground coal gasification (UCG) process for an actual UCG site. The optimization is performed to compensate for the uncertainty in coal and char ultimate analysis (caused by repeated measurements of different samples) and in steam to oxygen (O 2 ) ratio at the reaction front. The constrained nonlinear optimization problem is solved by using state of the art sequential quadratic programing (SQP) algorithm to minimize the error between experimental and simulated heating values. The results of the optimized model are validated with actual filed trials which show a good match for heating value of the product gases. The super twisting controller, a second order sliding mode control (SOSMC) algorithm is successfully implemented on the process model, which keeps the heating value of the product gas at the desired level in the presence of the matched disturbance: steam produced from water influx from surrounding aquifers and due to the moisture content of the coal. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a distributed model predictive control (DMPC) algorithm based on Benders’ decomposition for temperature regulation in buildings using multiple heating sources. It is well known that the main objective of this control problem is to minimize the heating energy bills while maintaining a certain indoor thermal comfort. To reduce the heating costs, many buildings are equipped with different heating sources. An example is the use of a hot water based central heating system and local electric convectors as complementary heating sources. Using a linear system model of the controlled process, the MPC optimization problem can be solved by linear programming. In order to reduce the computational demand required to solve the minimization problem, the authors propose a DMPC algorithm based on the Benders’ decomposition. The effectiveness of the proposed approach compared to the currently used PI-based control is illustrated in a simulation study. [Copyright &y& Elsevier]