Advanced Materials Research Vols. 383-390

Abstract: Due to the sedimentary environment, diagenesis and tectonization, the thickness of sandstone distribution show heterogeneity, which affect the result of waterflooding efficiency. The single-phase flow mathematic model was built to reveal the characteristic of plane heterogeneous reservoir. The result which was obtained by discrete differential method demonstrated that outlet flow velocity during thin-thickness location injection and thick production is higher than thin-thickness location production and thick injection. Then numerical simulation was applied to analyse the rate of production and injection, recovery percent and reservoir pressure in reservoir units. The result showed that the reservoir pressure around injection well is lower and the production and injection rate is higher during thin-thickness location injection and thick production, which provide theoretical basis for the development of thick production and thin injection.

Abstract: Up to now, there is no precedent of applying two bipole lines (TBL) on the same tower technology of long-distance HVDC transmission project in the world. Owing to mutual influence between the two HVDC circuits on the same tower, the traditional protection of transmission line is faced with technical difficulties on fault pole identification, especially high grounded fault loop impedance. A new protection scheme of transmission lines for the double ±500kV HVDC circuits on the same tower is proposed. Based on electromagnetic decoupling method for TBL on same tower is proposed by analyzed the characteristic of coupling mutual induction, a four module components is proposed to decouple the network equation and analyze the fault modal network. On this basis, a novel method of fault pole identification based on the polarity comparison of line-mode back traveling wave is proposed. It has been made that validates the advantage of this novel protection strategy to identify the fault pole by simulation of PSCAD/EMTDC on the model of the TBL ±500kV HVDC system on the same tower in Xiluodu-Guangdong China.

Abstract: Activated carbon derived from sewage sludge was impregnated in nitrate solution to produce a sorbent for sulfur dioxide adsorption at low concentration. The sulfur dioxide capacity was measured according to a laboratory-designed breakthrough test. After adsorption experiments on sulfur dioxide, desulfurizer JZ-Ni was chosen as the optimal sorbent owing to its largest sulfur dioxide capacity 57.6 mg•g^-1 and the highest BET 210.3031 m²•g ^-1. The effects of a few conditions on SO₂ removal behavior of the sorbent were studied. The results show that the sorbent JZ-Ni under the best conditions of 5714 mg•m^-3 inlet SO₂ concentration, 2000h^-1 space velocity and 393K desulfurization temperature, 0.3 mm particle diameter in steam has the maximum breakthrough sulfur dioxide capacity 58.2 mg•g^-1 .

Abstract: Phosphogypsum is the gypsum as a byproduct. It caused serious environment pollution. In this study, leaching As of phosphogypsum was studied by leaching equipment of self-made. We get some results of As heavy metals of the phosphogypsum affect the soil. The results show that: the content of arsenic is increasing and the pH of the soil is gradually decreased with the increasing of the leaching time. Different leaching velocity will cause different the content of arsenic of the soil.

Abstract: Advanced data assimilation method is used for the short-term wind power forecasting based on a meso-scale model. Considerable forecast error reduction is concluded from a case study in China, where a better resolved high-resolution initial condition is introduced via assimilating various in-situ observations.

Abstract: Slurry is a necessary material in high-speed railway pile foundation construction. A lot of waste slurry which is harmful to the eco-environment will be generated after the construction is finished. If the slurry isn’t disposed properly, it will cause serious pollutions to the environment. This paper analyses environmental impact of waste slurry through four aspects: surface water, crops, soil and wastewater treatment system etc. Finally, it gets the conclusion that there are four methods to reduce the environmental pollutions of waste slurry: the first one is using the environment-friendly slurry in pile foundation construction; the second one is raising the slurry use efficiency; the third one is decreasing the amount of slurry usage and the output of waste slurry; the last one is developing the more eco-friendly waste slurry treatment methods.

Abstract: Based on analyses on mineral composition, mechanical property and hydrology property, large-scale triaxial shear test and vibration test were used to study the effect on strength and deformation characteristic, which was caused by wet-chemical and soften of the fillings. Then trial roadbed was filled with 3 typical rocks. Modulus of resilience on the top of the roadbed was gotten via a larger-diameter (D=75 cm) plate loading test which could provide important parameter for pavement structure design. Wet-chemical deformation is researched under constant load amount to deadweight of the roadbed. Experiment results show : (1)single-axle compressive strength (>15 MPa) and modulus of resilience (E0=91.7 MPa) of 3 fillings match the requirement according to specification; (2) these 3 rocks can be used as filling in roadbed; (3) as the fillings have wet-chemical, soften, and expansion properties, the suggestion of damp-proofing and drainage works should be adopted in construction.

Abstract: Urban transport activities have an important impact on carbon emissions. The traditional Danwei compound created a better structural condition, providing people with the way of low-carbon transportation. In this paper, we discussed the impact of HUST campus space change to the choice of transportation for the school staff, and proposed that the low-carbon urban block special structure should be encouraged in the urban planning in order to reduce carbon emissions through constructing the mixed function urban blocks.

Abstract: An innovative step-feed Anaerobic-multiple Anoxic/Oxic-Membrane Bioreactor [An-M(A/O-MBR] process was developed to treat synthetic domestic wastewater. Performance of the lab-scale system was investigated at different dissolved oxygen (DO) concentration (0.4-2.4mg/L) in the aerobic tank of the multiple A/O zone. The results showed that, under the conditions imposed, the DO level has no obvious influence on COD removal and the removal efficiency was more than 94% throughout the operation. However, DO levels have great influence on nitrogen and phosphorus removal. Better nitrification performance(>99%) could be obtained when DO was in the range of 0.8~2.4mg/L. High total nitrogen (TN) and total phosphorus (TP) removal performance can be obtained when DO was in the range of 0.8~1.2mg/L, the average removal efficiency was 74.81% and 71.41%, respectively. In this condition, DO can meet the demand of nitrification and phosphorus uptake simultaneously, and the simultaneous nitrification and denitrification (SND) occurred in the aerobic tanks under 1ower DO concentration. Meanwhile, since the DO circulated from the aerobic tank to the anoxic tank decreased, denitrification was enhanced and the nitrate quantity in the sludge recycle system decreased, resulting in the decrease of carbon substrate competition between denitrifcation and phosphorus release in the anaerobic zone. Ultimately, the performance of TN and TP removal was enhanced.

Abstract: This paper proposes a direct three-dimensional (3D) numerical method in time domain for seismic soil-structure interaction (SSI) analysis of spatial grid structure. First, a finite element model including soil, foundation and typical spatial grid structure is developed. Then, the precisions of equivalent viscous-spring artificial boundary element (VSABE) and size effect of site soil region are discussed. Finally, under different site types, time history analyses for models with or without considering SSI effect are implemented respectively under horizontal seismic excitation. The results show that VSABE has the same precision as infinite element boundary and plane size of truncated soil region can be five times of structure plane size for SSI analysis of spatial grid structure. Moreover, except for hard site, it is shown that horizontal acceleration and displacement of spatial grid roof increases substantially when SSI effect is considered. Therefore, it is suggested that SSI influence should be taken into account in engineering design of spatial grid structure.