History matching is the process of modifying a numerical model (representing a reservoir) in the light of observed production data. In the oil and gas industry, production data are employed during a history matching exercise in order to reduce the uncertainty in associated reservoir models. However, production data, normally measured using commercial flowmeters that may or may not be accurate depending on factors such as maintenance schedules, or estimated using mathematical equations, inevitably has inherent errors. In other words, the data which are used to reduce the uncertainty of the model may have considerable uncertainty in itself. This problem is exacerbated for gas condensate and wet gas reservoirs as there are even greater errors associated with measuring small fractions of liquid. The influence of this uncertainty in the production data on history matching has not been addressed in the literature so far. In this paper, the effect of systematic and random flow measurement errors on history matching is investigated. Initially, 14 production data sets with different ranges of systematic and random errors, from 0 to 10%, have been employed in a history matching exercise for an oil reservoir and the results have later been evaluated based on a reference model. Subsequently, 23 data sets with errors ranging from 0 to 20% have been employed in the same process for a wet gas reservoir. The results show that for both cases systematic errors considerably affect history matching, while the effect of random errors on the considered scenarios is seen to be insignificant. Although reservoir model parameters in the wet gas reservoir were not as sensitive to the flow measurement errors as in the oil reservoir, for both cases, the future production forecast was significantly affected by the errors. Permeability was seen to be the most sensitive history matching parameter to the flow measurement errors in the oil reservoir, while for the wet gas reservoir, the most sensitive parameter was the forecast of future oil and gas production. Finally, considering the noticeable effect of systematic errors on both cases, it is suggested that flowmeter calibration and regular maintenance is prioritised, although the subsequent economic cost needs to be considered.
1 September 2019 in International Journal of Greenhouse Gas Control
Foundation industries are under increasing pressure to transform for sustainable development. Ceramics play a key role within foundation industries as a necessary material for building manufacturing facilities. Therefore, transforming the ceramic industry could support changes across other foundation industries as well, making it one of the most important industries to transform. Given the limited finances, staff time, and other resources to support transformative change, this study aims to identify a set of key intervention points to enable transformative change in the ceramic industry in the United Kingdom. A desk-based study, reviewing written industry, government, and scientific materials available in the public domain, was carried out to identify initial key intervention points for transformative change. The PESTLE approach was used to analyse macro factors in political, environmental, social, technological, legal, and economic domains in order to understand how the context enables or constrains change in the ceramic industry. A SWOT analysis was conducted to further consolidate the findings. Our analysis detected over 50 transformative change drivers and barriers and showed that decarbonisation and energy-saving strategies were the main drivers for transforming the UK ceramic industry. On the other hand, foreign government policy and legislation, trade barriers, skills shortages, and costly alternative energy sources were among the major barriers.