A systematic and focused engineering approach forproduction optimization and reservoir management of CoalBed Methane field developments is discussed. Such anapproach constitutes a decision making tool for productionoptimization of CBM fields.The paper briefly discusses the dynamics of thereservoir/production mechanisms, dewatering, desorption,fracturing mechanics and damage mechanisms affectingfracture conductivity and methane production. We present aset of best completion practices for CBM field ranging fromreservoir behavior of CBM reservoirs, formation evaluationapplications, reservoir modeling, production analysis,perforating for fracturing and completion design andoptimization.An integrated reservoir description is incorporated into thecompletion strategies by the development and use of aGeomechanical model that accounts for the reservoircharacterization and mechanical properties (pore pressures, k,Φ, saturations, coal quality, stress gradients, stress contrast,Young’s modulus, Poisson’s ratios). The approach results inan efficient design and optimum placement of hydraulicfracture stimulation treatments and provides the strategy forhigh grading the coal quality and selective stimulation of thecoal seams.A robust methodology for analysis of commingledproduction data is performed using historical production dataand advanced diagnostic procedures that match and predictperformance to accurately estimate reservoir potential, welldeliverability and completion efficiency. The uniqueprocedures combine superposition-in-time with rate-transientanalytic solutions for finite-conductivity vertically fracturedand non-fractured wells to accurately determine effectiveproperties. Simulation scenarios are created using a CBMsimulator and used for optimizing reservoir/field developmentscenarios to accelerate the dewatering process and increaseproduction by selective stimulation / completion criteria.The optimization process can effectively improve fieldperformance and economics and can be continuouslyimproved according to the evolving needs of the economics ofthe reservoir development.
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