CONSTRUCTION AND BUILDING MATERIALS
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2024
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IF 7.4
Zhipeng Zhu,Xiaoxue Song,Xiang Chi,Jingyao Zhao,Qiaofang Zhou,Antoni Sanchez‑Ferrer,Dengyun Tu,Wanli Cheng
Unilateral surface compression in wood presents notable benefits, including reduced wood volume loss and energy consumption, rendering a highly promising and extensive utilization. However, shortcomings in compressed wood arise due to unclear gas pressure, temperature, and moisture content distribution within the wood during hot pressing. In this paper, the temperature and pressure distribution were analyzed utilizing an optical fiber temperature and pressure measurement system within the wood during hot pressing. Moreover, the moisture content, stress and strain in each layer at the end of hot pressing were discussed extensively. The results showed that the wood surface layer (SL) and subsurface layer (SSL) maximum temperature values were similar even with different layer thicknesses. Under sealing conditions, SL and SSL temperatures were generally 6 ℃ to 7 ℃ higher compared to unsealing conditions. The gas pressure maximum value exhibited an opposite order, gradually transferring to the core layer (CL) and declining as the processing time extended. During compression treatment, moisture migrated from the hot end to the cold within the wood. The moisture content displayed significant differences between the middle and end parts of the wood under unsealed conditions, with the disparity becoming more pronounced further away from the hot end. The transition region of the compressed wood served as a stress concentration area, experiencing the highest levels of stress. The dense region followed with the second highest stress levels, while the un-densified region exhibited the least amount of stress. Under the same process parameters, the thickness had little influence on the distribution of dense layers.
研究领域:
木材科学
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材料科学
✓ 已验证
DOI
高影响因子
Petroleum Science
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2023
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IF 5.6
Xi-Dao Wu,Peng Xiao,Bei Liu,Guang-Jin Chen,Jian-Hua Pang
CO 2 emulsions used for EOR have received a lot of interest because of its good performance on CO 2 mobility reduction. However, most of them have been focusing on the high quality CO 2 emulsion (high CO 2 fraction), while CO 2 emulsion with high water cut has been rarely researched. In this paper, we carried out a comprehensive experimental study of using high water cut CO 2 /H 2 O emulsion for enhancing oil recovery. Firstly, a nonionic surfactant, alkyl glycosides (APG), was selected to stabilize CO 2 /H 2 O emulsion, and the corresponding morphology and stability were evaluated with a transparent PVT cell. Subsequently, plugging capacity and apparent viscosity of CO 2 /H 2 O emulsion were measured systematically by a sand pack displacement apparatus connected with a 1.95-m long capillary tube. Furthermore, a high water cut (40 vol%) CO 2 /H 2 O emulsion was selected for flooding experiments in a long sand pack and a core sample, and the oil recovery, the rate of oil recovery, and the pressure gradients were analyzed. The results indicated that APG had a good performance on emulsifying and stabilizing CO 2 emulsion. An inversion from H 2 O/CO 2 emulsion to CO 2 /H 2 O emulsion with the increase in water cut was confirmed. CO 2 /H 2 O emulsions with lower water cuts presented higher apparent viscosity, while the optimal plugging capacity of CO 2 /H 2 O emulsion occurred at a certain water cut. Eventually, the displacement using CO 2 /H 2 O emulsion provided 18.98% and 13.36% additional oil recovery than that using pure CO 2 in long sand pack and core tests, respectively. This work may provide guidelines for EOR using CO 2 emulsions with high water cut.
研究领域:
石油工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
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2019
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IF 5.108
Hua Wei,Yunong Tang,Tamer Shoeib,Aimin Li,Hu Yang
The preoxidation effects of H 2 O 2 , NaClO, and KMnO 4 on the dewaterability of sewage sludge were compared by analyzing the changes in specific resistance to filtration (SRF), filter cake moisture content (FCMC), extracellular polymeric substance (EPS) fractions and components, and floc properties. The three oxidants varied in oxidation efficiency and exhibited distinctive mechanisms. NaClO not only destroyed sludge flocs and EPSs but also effectively caused cell lysis, resulting in release of a considerable amount of organic matters and subsequently significant deterioration of dewatering performance. The oxidation of H 2 O 2 and KMnO 4 was relatively mild and occurred mainly on the outer layers of the sludge flocs and cell-bound EPSs. By contrast, the SRF and FCMC of the sludge conditioned with a low dose of KMnO 4 were slightly improved, and a fraction of soluble EPS was compressed because of the coagulation effect of the oxidation product MnO 2 . The pH of the sludge conditioned with H 2 O 2 and KMnO 4 showed no considerable change. Meanwhile, NaClO evidently increased the alkalinity of the sludge because of the hydrolysis effect. After the pH of the NaClO-treated sludge was readjusted to 7.0, the partial protonation efficiency slightly alleviated the deterioration of sludge dewatering performance. The preoxidized sludge was then subjected to reflocculation treatment using FeCl 3 , polyacrylamide, and a cationic starch-based flocculant , respectively. The combined treatment of preoxidation and reflocculation showed a high dewatering efficiency owing to their synergistic effect.
研究领域:
环境工程
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水处理
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Lu Bai,Guanjun Wang,Dongdong Ge,Yanting Dong,Hui Wang,Yuhui Wang,Nanwen Zhu,Haiping Yuan
Dewatering treatment is an essential step to diminish sludge volume, cut down transportation costs, and improve subsequent disposal efficiency. In this study, ozone-peroxymonosulfate (O 3 /PMS) oxidation process was employed to ameliorate sludge dewaterability. Sludge capillary suction time (CST) and water content (Wc) of dewatered sludge cake could reduce from 70.5 s and 81.93% to 26.7 s and 65.65%, respectively, under the optimal dosage of 30 mg/g TS O 3 and 0.4 mmol/g TS PMS. The increased sludge zeta potential , particle size, and fluidity promoted sludge dewatering performance apparently. The decreased hydrophilic, fluorescent EPS components and proteins/peptides-like + Lipids percentage in EPS as well as the ratio of α-helix/(β-sheet + random coil) of treated EPS protein secondary structure was greatly responsible for the enhanced sludge dewaterability. SO 4 − and OH were detected in ozone-peroxymonosulfate process to crack sludge flocs, eliminate hydrophilic substances and liberate bound water. Moreover, the concentrations of both heavy metals and polycyclic aromatic hydrocarbons (PAHs) of sludge after O 3 /PMS conditioning were decreased, and the stability and toxicity of heavy metals were also reduced, except Zn. In conclusion, this work offered a comprehensive insight based on ozone-peroxymonosulfate (O 3 /PMS) advanced oxidation for improving the sludge dewaterability and environmental implication.
研究领域:
环境工程
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污水处理
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污泥管理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Omega
·
2025
·
IF 4.3
Yuanyuan Bai,Yang Wen,Wanfen Pu,Wen Fang,Xing Jin
The loose sandstone oil reservoirs in the sea mostly adopt gravel packing completion, which leads to a decrease in permeability in the near-well area. Conventional blocking agents were difficult to simultaneously meet the requirements of water cut reduction and oil production increase. Therefore, this paper constructs a temperature-resistant in situ self-growing dispersed gel system and evaluates its displacement performance. The research results show that the formulation of the dispersed gel system is optimized through thermogravimetric analysis, with the monomer concentration determined to be 12 wt % and the cross-linking agent concentration determined to be 0.7 wt %. To improve injectability, the initial water content of the preinjected emulsion is selected as 40%, and its solubilization ability is determined to be 498.8%. During the solubilization process (from 40% to 80% water content), the viscosity increases from 67.89 to 3836 mPa·s. The influence of the change in emulsion water content during the solubilization process on the particle size of the dispersed gel particles is clarified; that is, the particle size first increases and then decreases, reaching the maximum at 70%, and the particle size distribution range becomes wider. In addition, this dispersed gel system shows good strength and long-term stability under different salinities. This study provides a new idea for controlling water and increasing oil production in large well-spacing, loose sandstone oil reservoirs in the sea.
研究领域:
石油工程
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油藏模拟
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化学工程
·
胶体与界面科学
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地质学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）