Behavior of Natural Estrogens in Activated Sludge: Biodegradation in Semicontinuous Reactor under Aerobic, Anaerobic and Sequential Anaerobic/Aerobic Conditions

The behavior of natural estrogens was examined by separately spiking 17β-estradiol (E2) and estrone (E1) into semicontinuous activated sludge reactors operated under aerobic, anaerobic and sequential anaerobic/aerobic conditions. Under aerobic and anaerobic conditions, E1 was formed from E2. The cactivated sludge; biodegradation; estrogens; estradiol; estroneonversion of E1 to E2 was did not occur under aerobic conditions. The maximum conversion of E2 to E1 was higher than the maximum conversion of E1 to E2. Overall, the degradation rate of E2 (kE2) was much faster than that of E1 (kE1). The findings suggest that E1 is probably more persistent than E2 in effluent of sewage treatment plants

Disinfection Performance Against Salmonella Typhi in Water by Radio Frequency Inductive Couple Plasma System

The disinfection performance of the radio frequency inductively coupled plasma (RFICP) system against Salmonella Typhi in water was examined using continuous flow experiments. The evaluation was based on disinfection efficiency, death rate constant, disinfection yield, and energy consumption. For all experiments the electromagnetic flux generated in the plasma reactor varied from 4 to 6 W/cm2. The disinfection efficiency and death rate constant of Salmonella Typhi decreased with the increase of the initial number of Salmonella Typhi bacteria. The disinfection yield increased from 784 to 1889 CFU/KWh and the energy consumption decreased from 0.28 to 0.07 KWh/L with the flowrate increasing from 5 to 20 mL/minute. The flowrate is an important parameter in predicting disinfection performance against pathogenic bacteria in water to design drinking water treatment plants

Structural evolution and mechanism of multi-phase rift basins: A case study of the Panyu 4 Sag in the Zhu Ⅰ Depression, Pearl River Mouth Basin, South China Sea

The study of changes in normal fault systems during different rift stages is important to understand the genesis and evolution of multi-phase rift basins, such as the Panyu 4 Sag in the Zhu Ⅰ Depression. Using 2D and 3D seismic data and analogue modelling, the Zhu Ⅰ Depression was characterized as a series of half-grabens bounded by NE-NEE-trending normal faults, it was found to have undergone two phases of the extension during the Paleogene. The Zhu Ⅰ Depression exhibited four fault sets with different strikes, including NNE, NE-NEE, EW, and NWW. The main controlling faults were NE-trending and EW-trending with high activity rates during Rift Phase 1 and Rift Phase 2, respectively. The average azimuths of the dominant strikes for type Ⅰa, type Ⅰb, and type Ⅱ faults were 75°, 85°, and 90°, which revealed that the minimum principal stress (σ3) directions during the rift phases 1 and 2 of the Zhu Ⅰ Depression were SSE (∼165°) and near-EW (∼180°), respectively. Two phases of structural-sedimentary evolution, with different directions and analogue modelling results, illustrated that the Panyu 4 Sag was formed as a superimposed basin under multi-phase anisotropic extension. The structural evolution of the Panyu 4 Sag since the Paleogene was mainly controlled by the combined effects of the Pacific, Eurasian, and Indian plates. Since the orientation of subduction of the Pacific plate changed from NNW to NWW, the stress field shifted from NW-SE-trending tension to S-N-trending tension, causing the superimposition of late near-E-W-oriented structural pattern on the early NE-oriented structural pattern

Quantitative prediction of palaeo-uplift reservoir control and favorable reservoir formation zones in Lufeng Depression

In this paper, taking the Lufeng Depression as the study object, the distribution characteristics and reservoir-controlling conditions of palaeo-uplift are analyzed from both qualitative and quantitative perspectives. The distribution characteristics of the three-level palaeo-uplift structural pattern are elucidated, which show that the palaeo-uplifts went through three structural evolutionary stages: Eocene, Early-Middle Miocene, and Late Miocene, with long-term inherited development characteristics. Palaeo-uplift controls the distribution of hydrocarbon planes, the direction of dominant hydrocarbon transport, the development of various traps, and the types of hydrocarbon reservoirs. Applying the principle and method of “multi-element matching reservoir formation model”, the corresponding geological and mathematical models are established, which indicate that 86.29% of the number of reservoirs are distributed on the top and slope of the palaeo-uplift, and the reserves and number decrease with the distance to the top of the palaeo-uplift. Based on the palaeo-uplift control model, four high-probability areas for palaeo-uplift control in the Wenchang and Enping Fms are predicted, which are mainly located in the Lufeng middle-low uplift, the Dongsha uplift, and uplifts within the depression.Cited as: Guo, B., Yu, F., Wang, Y., Li, H., Li, H., Wu, Z. Quantitative prediction of palaeo-uplift reservoir control and favorable reservoir formation zones in Lufeng Depression. Advances in Geo-Energy Research, 2022, 6(5): 426-437. https://doi.org/10.46690/ager.2022.05.0

Characteristics of NOM Released to Water from Different Forest and Agricultural Soils

The characteristics of natural organic matter (NOM) released to water from a soil environment were investigated based on the release potential and the quality indexes of SUVA, fluorescence EEM and molecular weight distribution using eight forest and agricultural soils collected from a representative river catchment (Kani River catchment in Gifu, Japan). The content of organic matter (OM) and its release potential to water differed obviously with type of soil origin, in the following order: vegetable field (VF) < paddy field (PF) < broadleaf forest (BF) < coniferous forest (CF) and VF < PF < CF < BF, respectively. For the released NOM, SUVA under different pH conditions decreased in the following order: neutral condition [3.6-24.0 m-1/(mg/L)] > basic condition [3.5-8.0 m-1/(mg/L)] > acidic condition [2.5-3.0 m-1/(mg/L)]. Humic acids (P1), fulvic acids (P2) and protein-like substances (P3) were the main components of the NOM released under neutral condition. The proportion of P1 and P2 released from the forest soils was lower than that from the agricultural soils. Marked differences in UV-absorbing constituents of NOM between forest and agricultural soils were found in the peak with a molecular weight of about 9800 g/mol identified as PSS (polystyrene sulfonate)

Quantitative prediction of structural fractures in the Paleocene lower Wenchang formation reservoir of the Lufeng Depression

Currently, the lower Paleogene Wenchang formation in the Lufeng Depression is the primary focus of reservoir development. The structural fractures that have formed inside of it not only serve as the principal path for oil migration, but also as oil storage space. As a result, the distribution features of structural fractures are crucial for future petroleum exploration and development in the Lufeng Depression. At the same time, with the quantity of conventional reservoirs in the Lufeng Depression on the decline, it is critical to determine the fracture distribution criteria for deep unconventional reservoirs. In this work, the lower Paleogene Wenchang formation in the Lufeng Depression is used as the research stratum. Then, based on existing logging data for the research region, the distinct physical properties of different rock kinds are calculated. The simulation results of the paleotectonic stress field in the study area using the finite element numerical simulation software ANSYS show that the high-value areas of maximum principal stress are the high-value areas of the uplift belt and low uplift, and the areas with low maximum principal stress are the low-value areas of Lufeng 13 Sag and the gentle slope belt in the north of Lufeng middle-low uplift. The fracture density is quantitatively predicted after the stress field simulation, which shows good agreement between the anticipated and actual observed values, and an average error of 13.61%. The predicted findings may provide new ideas for future petroleum exploration.cited as: Li, H., Yu, F., Wang, M., Wang, Y., Liu, Y. Quantitative prediction of structural fractures in the Paleocene lower Wenchang formation reservoir of the Lufeng Depression. Advances in Geo-Energy Research, 2022, 6(5): 375-387. https://doi.org/10.46690/ager.2022.05.0