An engineering-environmental-economic-energy assessment for integrated air pollutants reduction, CO2 capture and utilization exemplified by the high-gravity process.

In this study, a high-gravity (HiGee) process incorporating CO2 and NOx reduction from flue gas in a petrochemical plant coupled with petroleum coke fly ash (PCFA) treatment was established. The performance of HiGee was systematically evaluated from the engineering, environmental, economic, and energy aspects (a total of 15 key performance indicators) to establish the air pollution, energy efficiency, waste utilization nexus. The engineering performance was evaluated that lower energy consumption of 78 kWh/t-CO2 can be achieved at a capture capacity of 600 kg CO2/t-PCFA. A net emission reduction of 327.3 kg-CO2/t-PCFA could be determined based on six environmental impact indicators. A cost-benefit analysis was conducted using operating cost, product sale, carbon credit, and savings in air pollution fees to present a better technological selection compared to existing carbon capture and storage plants. The waste heat recovery from the flue gas via the HiGee process could be measured via moisture condensation and attendant elimination of white smog emissions. Retrofitted heat recovery and energy intensity up to 131.8 kJ/t-PCFA and 0.21 kWh/t-PCFA were assessed. Finally, a comprehensive analysis of the HiGee process based on three daily load scenarios of CO2 capture scale were conducted, suggesting an optimal operating condition of the HiGee for generating profitability.

Redundant and Nonredundant Information for Model Calibration or Hydraulic Tomography.

Drawdown data from independent pumping tests have widely been used to validate the estimated hydraulic parameters from inverse modeling or hydraulic tomography (HT). Yet, the independent pumping test has not been clearly defined. Therefore, the goal of this paper is to define this independent pumping test concept, based on the redundant or nonredundant information about aquifer heterogeneity embedded in the observed heads during cross-hole pumping tests. The definition of complete, moderate redundancy and high nonredundancy of information are stipulated using cross-correlation analysis of the relationship between the head and heterogeneity. Afterward, data from numerical experiments and field sequential pumping test campaigns reinforce the concept and the definition.