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Numerical simulation of profile control by clay particles after polymer flooding

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Petroleum Science 2010年第4期7卷 509-514页

作者： Feng Qihong Shi Shubin Wang Sen Zheng Lu School of Petroleum Engineering China University of Petroleum Qingdao Shandong 266555 China School of Petroleum Engineering China University of Petroleum Beijing 102249 China Shengli Oil Production Research Institute SINOPEC Dongying Shandong 257000 China Bozhong Operation Company CNOOC Tianjin 300452 China

A three-dimensional,two-phase,five-component mathematical model has been developed to describe flow characteristics of clay particles and flocs in the profile control process,in which the clay particle suspension is injected into the formation to react with residual *** model considers the reaction of clay particles with residual polymer,apparent viscosity of the mixture,retention of clay particles and flocs,as well as the decline in porosity and permeability caused by the retention of clay particles and flocs.A finite difference method is used to discretize the equation for each component in the *** Runge-Kutta method is used to solve the polymer flow equation,and operator splitting algorithms are used to split the flow equation for clay particles into a hyperbolic equation for convection and a parabolic equation for diffusion,which effectively ensures excellent precision,high speed and good *** numerical simulation had been applied successfully in the 4-P1920 unit of the Lamadian Oilfield to forecast the blocking capacity of clay particle suspension and to optimize the injection parameters.

关键词： Clay particles flocs detention operator splitting algorithms numerical simulation

维普期刊数据库

Experimental modelling of flocculation processes-the case of Paraiba do Sul Estuary

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International Journal of Sediment Research 2014年第3期29卷 378-390页

作者： Alfredo TRENTO Susana VINZON Department of Hydraulics National University of LitoralSanta FeArgentina Programa de Engenharia Oceanica(PEnO)/COPPE Federal University of Rio de JaneiroRio de JaneiroBrazil

The aggregation dynamics of fine sediments was analysed through laboratory tests using Couette and disk *** was shown that floc sizes tend to increase as concentrations grow both in fresh and salt water,in agreement with the aggregation theory,and that equilibrium diameters are slightly greater in salt environments for flocs developed either under shear stress or by differential *** transport and the aggregation processes were preliminarily studied in the estuary of the Paraiba do Sul River using a particle tracking model and field *** floc breakup process by shear stress was included in the *** stresses,which were determined by fractal dimensions and differential density,were accounted *** the calibration of the collision efficiency coefficients,the numerical model was able to predict floc sizes comparable with those measured at the Paraiba do Sul estuary,which,in turn,were similar to those obtained during the laboratory experiments in the Couette flocculator.

关键词： flocs Flocculators Transport proceses Paraiba do Sul

Floc meal as potential substitute for soybean meal in tilapia diets under biofloc system conditions

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Journal of Oceanology and Limnology 2019年第1期37卷 313-320页

作者： Rania S. MABROKE Osama M. EL-HUSSEINY Abd El-Naem F. A. ZIDAN Al-Azab TAHOUN Ashraf SULOMA Fish Nutrition Laboratory (FNL) Animal Production Department Faculty of Agriculture Cairo University Aquaculture Department Faculty of Fish ResourcesSuez University

This study was conducted to evaluate the ef fect of replacing soybean meal(SBM) by low protein ?oc meal(LPFM; 24% CP) in tilapia diets on growth performance, feed utilization and ?sh chemical composition. Three isonitrogenous and isocaloric diets were formulated; control diet(C; without LPFM),FM 25(25% of SBM protein was substituted by LPFM) and FM 50(50% of SBM protein was substituted by LPFM). Nine 55 l circular plastic tanks were stocked by 12 ?sh to form three experimental *** dif ferences in tilapia performance were observed between the control and the FM 25 diet. Chemical composition of ?sh did not dif fer signi?cantly among treatments except for protein and selenium contents where the highest values were recorded in the control treatment. The highest mineral content was recorded in ?oc collected from the control tanks, while calcium content showed its highest value in ?oc collected from FM 50 e ? uent. These data indicate that replacing soybean meal with LPFM up to 25%, had no negative ef fect on growth performance and potentially may improve the system sustainability. Meanwhile, the adverse ef fect of more inclusion of LPFM in tilapia diet may be attributed to the higher content of ash. In other word,minerals seem to cause more energy utilization in ?sh fed ?oc meal since it is needed to maintain osmotic homeostasis.

关键词： microbial flocs alternative protein sources tilapia diet sustainability

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Effects of Different Cations on the Flocculation and Sedimentation of Static Fine-Grained

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Journal of Environmental & Earth Sciences 2023年第2期5卷 1-14页

作者： Xiaomin Liu Yaotian Yang Rui Wang Wenjuan Wang Qiang Luo College of Water Conservancy and Civil Engineering Inner Mongolia Agricultural UniversityHohhotInner Mongolia010018China Collaborative Innovation Center for Integrated Management of Water Resources and Water Environment in the Inner Mongolia Reaches of the Yellow River HohhotInner Mongolia010018China Inner Mongolia JinHua Yuan Environmental Resource Engineering Consulting Co. ItdHohhotInner Mongolia010020China Wuhai Wuda District Agriculture of Animal Husbandry and Water Affairs Bureau WuhaiInner Mongolia016000China Yellow River Hai Bo-Wan Water Conservancy Project Development Center WuhaiInner Mongolia016000China

Natural water bodies mostly contain cations,and the type and content of these cations are the main factors affecting the flocculation of fine-grained cohesive sediments and the floc sedimentation rate at the interface between clear and turbid *** the microscopic aspect,this study examined the changing patterns of porosity and the fractal dimension of the flocs of fine-grained cohesive *** experiments under different sediment contents and electrolyte conditions were conducted,and microscopic images of the flocs were analysed using Image-Pro Plus(IPP)and MATLAB based on the fractal *** the macroscopic aspect,this study experimentally investigated the flocculation and sedimentation of fine-grained cohesive sediments and proposed a sedimentation rate equation by introducing an ion concentration-related parameter into an existing sedimentation rate equation(stagnation zone)based on the adsorption isotherm *** equation proposed in this study was validated with measured *** calculated values were in good agreement with the measured values,with a relative error of 16%.The findings of this study provide a reference for further research on the flocculation and sedimentation of fine-grained cohesive sediments in different water bodies.

关键词： flocs Electrolyte Fractal dimension Porosity Sedimentation rate

Fate of proteins of waste activated sludge during thermal alkali pretreatment in terms of sludge protein recovery

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Frontiers of Environmental Science & Engineering 2019年第2期13卷 115-123页

作者： Xiaoli Song Zhenghua Shi Xiufen Li Xinhua Wang Yueping Ren Laboratory of Environmental Biotechnology School of Environmental and Civil EngineeringJiangnan UniversityWuxi 214122China Jiangsu Key Laboratory of Anaerobic Biotechnology Wuxi 214122China Jiangsu Cooperative Innovation Center of Technology and Material of Water Treatment Suzhou 215009China

Proteins are the major organic component s of waste activated sludge(WAS);the recovery of sludge proteins is economically *** efficiently recover sludge proteins,WAS should undergo hydrolysis pretreatment to fully release proteins from sludge flocs and microbial cells into aqueous *** of the most widely used chemical methods for that is thermal alkali hydrolysis(TAH).Here,the soluble protein concentration achieved the highest level over 90 min of TAH pretreatment at 80°C;the sludge floc disintegration and microbial cell destruction were maximized according to the content profiles of bound extracellular polymeric substance(EPS)and ribonucleic acid(RNA)of *** less proteins broken down to materials with small molecular weight and less melanoidin generated were *** pretreatment at 80°C for 90 min resulted in the solubilization of 67.59% of sludge proteins.34.64% of solubilized proteins was present in soluble high molecular;1.55% and 4.85% broke down to polypeptides and amino *** lost proteins via being converted to ammonium and nitrate nitrogen accounted for 9.44% of solubilized *** was important to understand the fate of sludge proteins during TAH pretreatment in terms of protein recovery,which would be helpful for designing the downstream protein separation method and its potential application.

关键词： Sludge flocs Microbial cells Hydrolysate Protein breakdown Melanoidin

Filter Efficiency with Red Rock as Post-Treatment of Stabilization Pond Effluent, Prototype Case Study San Marcos, Carazo, from April to September 2019

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Open Journal of Applied Sciences 2022年第5期12卷 806-817页

作者： Víctor Rogelio Tirado Picado American University (UAM) Managua Nicaragua

An experimental unit was built which was located in the vicinity of the domestic wastewater treatment plant of the Municipality of San Marcos in the Department of Carazo. Said unit consisted of two welded metal barrels with a total height of 1.8 m and a diameter of 0.90 m, likewise, this unit comprised three functional zones;the first or input area composed of a collection unit, a driving unit, a flow control unit, and two distribution units;the second or packed zone, which is the axis of the system because it is there where bacterial growth takes place and where the removal of organic matter takes place;and an outlet composed of PVC pipe [1]. The main objective of this work was to determine how efficient a rocky filter turns out to be, using stabilization pond effluent as a post-treatment unit using red concrete as a filter medium. The study consisted in carrying out laboratory tests on water samples taken from the influent and effluent of a filter made up of red rock, as a filter medium, in order to determine the percentage of organic matter removal efficiency that it has used a hydraulic retention time of 19 hours, 15 hours, and 12 hours [2]. Among the aspects to be considered in the experimental study was the characterization of the effluent from the treatment system of San Marco, Carazo, to determine the quality of water that will be of interest to the study [3]. In this stage, four composite samplings were carried out, two of 12 hours and two of 24 hours, in which physical, chemical, and microbiological parameters were analyzed. Likewise, to determine the efficiency of the filter, the same parameters considered in the characterization of the lagoon effluent were analyzed, obtaining removal efficiencies of up to 55.53% in organic matter, and 64.60% in suspended solids for a hydraulic retention time of 19 hours;In the same way, the efficiency of the filter was carried out for retention times of 15 hours and 12 hours, in which organic matter removals of 67.84% an

关键词： Design Filter Flow flocs Transport Water Quality

Comparison of Coagulation Efficiencies of Tannic Acid Containing Turbidity Water by using Alum and Poly-aluminum Chloride as Coagulants

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Comparison of Coagulation Efficiencies of Tannic Acid Contai...

Interplay Factors Involved in the Inadequate Performance of Four Activated Sludge Systems in Northern Gauteng-South Africa

2011 International Conference on Agricultural and NaturalResources Engineering (ANRE 2011)

作者： Chen Zhong-lin Wang Xiao-rong Shen Ji-min Wang Bin-yu Liu Xiao-wei Zhao Sheng-xin State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology

Coagulation efficiencies of alum and poly-aluminum chloride（PACl） were compared for treating tannic acid containing turbidity water in terms of residual turbidity, p H, UV254, DOC, Zeta potential and residual aluminumThe growth and microtopography of flocs were also studied by the system of photo collected, electron microscope and atom force microscopeThe results showed that alum could removal turbidity, UV254 and DOC more efficiently than PACl with lower residual alum;after the addition of coagulants, the flocs formed by PACl appeared earlier and were larger than that by alum;the sediments formed by PACl contained more waterTherefore, alum was more efficient than PACl for treating tannic acid containing turbidity water.

关键词： Coagulation tannic acid alum PACl flocs

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Journal of Environmental Science and Engineering 2010年第6期4卷 1-12页

作者： M.N.B. Momba M. Dungeni Environmental Water and Earth Sciences Tshwane University of Technology Arcadia 0001 South Africa

A recent study conducted on the four activated systems serving the surrounding communities in the Northern Gauteng revealed the failure of three of these wastewater treatment plants to remove enteric pathogenic bacteria and protozoan parasites such as Cryptosporidium and Giardia spp. To determine the factors involved in the inadequate performance of the plants, the following parameters were considered： the design characteristic of the plants, the microbiological structure and the physical characteristics of the plants. The results revealed that higher than optimal influent loadings and inadequate aeration systems, observed in Baviaanspoort, Refilwe and Rayton Water Care Works （WCW） increased the composition of filamentous bacteria in flocs and decreased the diversity of protozoan species in the sludge. Sequentially, these resulted in the poor settling properties of the sludge at these plants. However, Zeekoegat WCW showed optimum influent loads and adequate aeration systems. This maintained balance in the microbial community, resulting in good clarification of the sludge.

关键词： Performance activated sludge design capacity protozoa flocs settleability.

新型高铁硅混凝剂形成的铅絮体的分形维数分析(英文)

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新型高铁硅混凝剂形成的铅絮体的分形维数分析(英文)