Active control has been recognised as one of the most promising methods to mitigate slugging by s... more Active control has been recognised as one of the most promising methods to mitigate slugging by several researchers. However, choke valves used in offshore oil and gas production systems are often in a large size with a very large stroke time (time for a valve traveling from fully open to fully close or vice versa). This leads to not only a significant but also variable input time delay because the actual time delay also depends on the input increment value at each sampling point. In many practical offshore slug control systems, the large valve stroke time has been a major factor impacting significantly on the slug control performance. In this work, a modified Smith predictor is proposed to resolve this problem. Firstly, the traditional Smith predictor, which was mainly designed for fixed measurement time delay, is specially modified for variable input time delay using measureable delayed signal (actual valve position). Then, a linear model is adopted to present the slugging system ...
There is an increased focus on the reduction of anthropogenic emissions of CO2, and this has resu... more There is an increased focus on the reduction of anthropogenic emissions of CO2, and this has resulted in CO2 capture processes for storage in geological formations or enhanced oil recovery. The necessary link between the capture and storage process is the transport system. Ship-based transport of CO2 is a better option when the distance exceeds 350 km compared to an offshore pipeline and offers more flexibility for transportation, unlike pipelines which require a continuous flow of compressed gas. Liquefied CO2 ship transportation is mainly used in food industries with capacities ranging from 8001000 m. For carbon capture and storage (CCS) purposes, a more significant size is needed. Several feasibility studies have been undertaken to ascertain the viability of large-scale transportation of CO2 by shipping regarding the liquefaction process, gas conditioning, but limited work exists on emission reduction from the ship’s engine fuel combustion. Figure 1: Capture process for both CO2 ...
Active control has been recognised as one of the most promising methods to mitigate slugging by s... more Active control has been recognised as one of the most promising methods to mitigate slugging by several researchers. However, choke valves used in offshore oil and gas production systems are often in a large size with a very large stroke time (time for a valve traveling from fully open to fully close or vice versa). This leads to not only a significant but also variable input time delay because the actual time delay also depends on the input increment value at each sampling point. In many practical offshore slug control systems, the large valve stroke time has been a major factor impacting significantly on the slug control performance. In this work, a modified Smith predictor is proposed to resolve this problem. Firstly, the traditional Smith predictor, which was mainly designed for fixed measurement time delay, is specially modified for variable input time delay using measureable delayed signal (actual valve position). Then, a linear model is adopted to present the slugging system ...
There is an increased focus on the reduction of anthropogenic emissions of CO2, and this has resu... more There is an increased focus on the reduction of anthropogenic emissions of CO2, and this has resulted in CO2 capture processes for storage in geological formations or enhanced oil recovery. The necessary link between the capture and storage process is the transport system. Ship-based transport of CO2 is a better option when the distance exceeds 350 km compared to an offshore pipeline and offers more flexibility for transportation, unlike pipelines which require a continuous flow of compressed gas. Liquefied CO2 ship transportation is mainly used in food industries with capacities ranging from 8001000 m. For carbon capture and storage (CCS) purposes, a more significant size is needed. Several feasibility studies have been undertaken to ascertain the viability of large-scale transportation of CO2 by shipping regarding the liquefaction process, gas conditioning, but limited work exists on emission reduction from the ship’s engine fuel combustion. Figure 1: Capture process for both CO2 ...
Uploads
Papers by Adeola Awoyomi