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Simulation of Gas-Water Two-Phase Flow in Tight Gas Reservoirs Considering the Gas Slip Effect
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作者 Mingjing Lu Zenglin Wang +3 位作者 Aishan Li Liaoyuan Zhang Bintao Zheng Zilin Zhang 《Fluid Dynamics & Materials Processing》 EI 2023年第5期1269-1281,共13页
A mathematical model for the gas-water two-phase flow in tight gas reservoirs is elaborated.The model can account for the gas slip effect,stress sensitivity,and high-speed non-Darcy factors.The related equations are s... A mathematical model for the gas-water two-phase flow in tight gas reservoirs is elaborated.The model can account for the gas slip effect,stress sensitivity,and high-speed non-Darcy factors.The related equations are solved in the framework of a finite element method.The results are validated against those obtained by using the commercial software CMG(Computer Modeling Group software for advanced recovery process simulation).It is shown that the proposed method is reliable.It can capture the fracture rejection characteristics of tight gas reservoirs better than the CMG.A sensitivity analysis of various control factors(initial water saturation,reservoir parameters,and fracturing parameters)affecting the production in tight gas wells is conducted accordingly.Finally,a series of theoretical arguments are provided for a rational and effective development/exploitation of tight sandstone gas reservoirs. 展开更多
关键词 Tight gas reservoir gas-water two-phase flow numerical simulation fractured horizontal well gas slip effect
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Effect of powdered activated carbon on Chinese traditional medicine wastewater treatment in submerged membrane bioreactor with electronic control backwashing 被引量:8
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作者 LIU Xiao-lei REN Nan-qi MA Fang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第9期1037-1042,共6页
Chinese traditional medicine wastewater, rich in macromolecule and easy to foam in aerobic biodegradation such as Glycosides, was treated by two identical bench-scale aerobic submerged membrane bioreactors (SMBRs) o... Chinese traditional medicine wastewater, rich in macromolecule and easy to foam in aerobic biodegradation such as Glycosides, was treated by two identical bench-scale aerobic submerged membrane bioreactors (SMBRs) operated in parallel under the same feed, equipped with the same electronic control backwashing device. One was used as the control SMBR (CSMBR) while the other was dosed with powdered activated carbon (PAC) (PAC-amended SMBR, PSMBR). The backwashing interval was 5 min. One suction period was about 90 min by adjusting preestablished backwashing vacuum and pump frequency. The average flux of CSMBR during a steady periodic state of 24 d (576 h) was 5.87 L/h with average hydraulic residence time (HRT) of 5.97 h and that of PSMBR during a steady periodic state of 30 d (720 h) was 5.85 L/h with average HRT of 5.99 h. The average total chemical oxygen demand (COD) removal efficiency of CSMBR was 89.29% with average organic loading rate (OLR) at 4.16 kg COD/(m^3.d) while that of PSMBR was 89.79% with average OLR at 5.50 kg COD/(m^3.d). COD concentration in the effluent of both SMBRs achieved the second level of the general wastewater effluent standard GB8978-1996 for the raw medicine material industry (300 mg/L). Hence, SMBR with electronic control backwashing was a viable process for medium-strength Chinese traditional medicine wastewater treatment. Moreover, the increasing rates of preestablished backwashing vacuum, pump frequency, and vacuum and flux loss caused by mixed liquor in PSMBR all lagged compared to those in CSMBR; thus the actual operating time of the PSMBR system without membrane cleaning was extended by up to 1.25 times in contrast with the CSMBR system, and the average total COD removal efficiency of PSMBR was enhanced with higher average OLR. 展开更多
关键词 electronic control backwashing powdered activated carbon membrane bioreactor aerobic process wastewater treatment
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Application of a novel backwashing process in upflow biological aerated filter 被引量:7
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作者 Jinshui Yang Weijie Liu +3 位作者 Baozhen Li Hongli Yuana Meiping Tong Jinsong Gao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第3期362-366,共5页
To improve the efficiency of backwashing in upflow biological aerated filter (BAF), a novel backwashing process named air-water siphon backwashing (AWSB) was proposed and applied on laboratory scale. The effects o... To improve the efficiency of backwashing in upflow biological aerated filter (BAF), a novel backwashing process named air-water siphon backwashing (AWSB) was proposed and applied on laboratory scale. The effects of backwashing on turbidity and suspended solid (SS) in backwashing efluent using this new backwashing process were compared with those of traditional backwashing process, namely air-water backwashing (AWB). In AWB, the turbidity of backwashing efluent maintained 100 NUT when consumed 60 min and 10.5 L water. However, in AWSB, it declined to 44 NUT, consumed 40 min, and 7 L water. The COD removal of BAF after backwashing was also analyzed. The average removal rate of COD in the reactor backwashed by AWB and AWSB was 89.34% and 90.91%, respectively. Compared with AWB, the backwashing interval had been prolonged 35%. The volume of backwashing water in that AWSB was only 66.7% of that in AWB. The results demonstrated that AWSB required less water and took shorter backwashing timerelative to AWB to achieve the same turbidity of backwashing efluent, and AWSB was more effective in removing fouling than that of AWB. More significant advantage of AWSB was that the backwashing interval was effectively prolonged 展开更多
关键词 biological aerated filter air-water siphon backwashing chemical oxygen demand
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Gas-water stratified flow patterns from electromagnetic tomography 被引量:7
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作者 Wang Xiaoxing Wu Xiling 《Petroleum Science》 SCIE CAS CSCD 2009年第3期254-258,共5页
Because of gravitational differentiation of multi-phase fluids, gas-water flow is usually stratified in highly inclined or horizontal gas wells. By using electrode arrays to scan flowing fluids, electromagnetic tomogr... Because of gravitational differentiation of multi-phase fluids, gas-water flow is usually stratified in highly inclined or horizontal gas wells. By using electrode arrays to scan flowing fluids, electromagnetic tomography can identify the flow patterns of mixed fluid from the different electrical properties of gas and water. The responses for different gas-water interface locations were calculated and then physical measurements were undertaken. We compared the results of the numerical simulation with the experimental data, and found that the response characteristics were consistent in the circumstances of uniform physical fields and stratified flows. By analyzing the signal characteristics, it is found that, with the change of the interface location, the response curves showed "steps" whose position and width were decided by the location of fluid interface. The measurement accuracy of this method depended on the vertical distance between adjacent electrodes. The results showed that computer simulation can simulate the measurement of the electromagnetic tomography accurately, so the physical experiment can be replaced. 展开更多
关键词 Electromagnetic tomography stratified flow gas-water numerical simulation physical experiment
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Pore-Throat Combination Types and Gas-Water Relative Permeability Responses of Tight Gas Sandstone Reservoirs in the Zizhou Area of East Ordos Basin, China 被引量:5
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作者 LI Mi GUO Yinghai +2 位作者 LI Zhuangfu WANG Huaichang ZHANG Jingxia 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第3期622-636,共15页
With the aim of better understanding the tight gas reservoirs in the Zizhou area of east Ordos Basin,a total of 222 samples were collected from 50 wells for a series of experiments.In this study,three pore-throat comb... With the aim of better understanding the tight gas reservoirs in the Zizhou area of east Ordos Basin,a total of 222 samples were collected from 50 wells for a series of experiments.In this study,three pore-throat combination types in sandstones were revealed and confirmed to play a controlling role in the distribution of throat size and the characteristics of gas-water relative permeability.The type-I sandstones are dominated by intercrystalline micropores connected by cluster throats,of which the distribution curves of throat size are narrow and have a strong single peak(peak ratio>30%).The pores in the type-II sandstones dominantly consist of secondary dissolution pores and intercrystalline micropores,and throats mainly occur as slice-shaped throats along cleavages between rigid grain margins and cluster throats in clay cement.The distribution curves of throat size for the type-II sandstones show a bimodal distribution with a substantial low-value region between the peaks(peak ratio<15%).Primary intergranular pores and secondary intergranular pores are mainly found in type-III samples,which are connected by various throats.The throat size distribution curves of type-III sandstones show a nearly normal distribution with low kurtosis(peak ratio<10%),and the micro-scale throat radii(>0.5μm)constitute a large proportion.From type-I to type-III sandstones,the irreducible water saturation(Swo)decreased;furthermore,the slope of the curves of Krw/Krg in two-phase saturation zone decreased and the two-phase saturation zone increased,indicating that the gas relative flow ability increased.Variations of the permeability exist in sandstones with different porethroat combination types,which indicate the type-III sandstones are better reservoirs,followed by type-II sandstones and type-I sandstones.As an important factor affecting the reservoir quality,the pore-throat combination type in sandstones is the cumulative expression of lithology and diagenetic modifications with strong heterogeneity. 展开更多
关键词 tight gas sandstone pore-throat COMBINATION type THROAT characteristic gas-water relative permeability Zizhou area ORDOS Basin
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Membrane Fouling Alleviation by Chemically Enhanced Backwashing in Treating Algae-Containing Surface Water: From Bench-Scale to Full-Scale Application
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作者 Xiaobin Tang Tiecheng Guo +7 位作者 Haiqing Chang Xiao Yue Jinlong Wang Haikuan Yu Binghan Xie Xuewu Zhu Guibai Li Heng Liang 《Engineering》 SCIE EI CAS 2022年第12期40-49,共10页
Ultrafiltration(UF)has been increasingly implemented in drinking water treatment plants;however,algae and their secretions can cause severe membrane fouling and pose great challenges to UF in practice.In this study,a ... Ultrafiltration(UF)has been increasingly implemented in drinking water treatment plants;however,algae and their secretions can cause severe membrane fouling and pose great challenges to UF in practice.In this study,a simple and practical chemically enhanced backwashing(CEB)process was developed to address such issues using various cleaning reagents,including sodium hypochlorite(NaClO),sodium chloride(NaCl),sodium hydroxide(NaOH),sodium citrate,and their combinations.The results indicate that the type of chemical played a fundamental role in alleviating the hydraulically irreversible membrane fouling(HIMF),with NaClO as the best-performing reagent,followed by NaCl.Furthermore,a CEB process using a combination of NaClO with NaCl,NaOH,or sodium citrate delivered little improvement in the alleviation of membrane fouling compared with NaClO alone.The optimized dosage and dosing frequency of NaClO were 10 mg·L^(-1) two times per day.Long-term pilot-scale and full-scale experiments further verified the feasibility of the CEB process in relieving algae-derived membrane fouling.Compared with the conventional hydraulic backwashing without chemical involvement,the CEB process can effectively remove the organic foulants including biopolymers,humic substances,and proteinlike substances by means of oxidization,thereby weakening the cohesive forces between the organic foulants and the membrane surface.Therefore,the CEB process can efficiently alleviate the algae-related membrane fouling with lower chemical consumption,and is proposed as an alternative to control membrane fouling in treating the algae-containing surface water. 展开更多
关键词 Ultrafiltration Membrane fouling Hydraulically irreversible membrane fouling Chemically enhanced backwashing(CEB) Algae-containing surface water
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Biomass and microbial activity in a biofilter during backwashing
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作者 白宇 张杰 +2 位作者 李一凡 郜玉楠 李泳 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第5期427-432,共6页
Biomass and microbial activity in backwashing processes of a biofilter for tertiary treatment were investigated. The microbial groups revealed new distribution along the biofilter depth after low flow rate backwashing... Biomass and microbial activity in backwashing processes of a biofilter for tertiary treatment were investigated. The microbial groups revealed new distribution along the biofilter depth after low flow rate backwashing for a short time. Then the start-up process was accelerated by backwashing. The biomass profile and microbial activity profile both varying with depth before and after backwashing, can be mathematically described by quadratic equations. Using the profiles, the difference of oxygen demand can be calculated to determine the airflow rate during backwashing. Combined with the difference between biofilters and rapid gravity filters, analysis of biomass and microbial activity can determine more accurately the required airflow rate during backwashing. 展开更多
关键词 微生物 活性 生物过滤器 废水处理工艺 需氧量
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Simultaneous Carbon and Nitrogen Removal in Wastewater Treatment Using a Partially Packed Biological Aerated Filter (BAF) without Backwashing Process
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作者 Z. Amir S. Fatihah +1 位作者 M. Denecke S.M. Zain 《Journal of Environmental Science and Engineering》 2010年第7期15-23,共9页
关键词 曝气生物滤池 反冲洗过程 除碳 废水处理 混合动力系统 盒装 容积负荷
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两种方法清洗消毒达芬奇机器人手术臂的效果比较
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作者 黎云霞 孙美花 +3 位作者 楼丽琼 喻杰 黎佳瑶 徐敏 《中国当代医药》 CAS 2024年第4期46-49,53,共5页
目的探讨达芬奇机器人手术臂有效的清洗消毒方法。方法回顾性分析2022年1月至2023年4月江西省人民医院手术室使用后的达芬奇机器人手术臂200件达芬奇机器人手术臂作为研究对象,按照不同的操作流程将其分为观察组(100件)与对照组(100件)... 目的探讨达芬奇机器人手术臂有效的清洗消毒方法。方法回顾性分析2022年1月至2023年4月江西省人民医院手术室使用后的达芬奇机器人手术臂200件达芬奇机器人手术臂作为研究对象,按照不同的操作流程将其分为观察组(100件)与对照组(100件)。观察组采用流动水冲洗+腹腔镜酶剂浸泡+超声波清洗机超声+蒸汽清洗机清洗手术臂操作端+高压水枪纯水漂洗+全自动清洗机清洗消毒。对照组清洗消毒流程为流动水冲洗+腹腔镜酶剂浸泡+超声波清洗机超声+刷洗手术臂操作端+高压水枪纯水漂洗+全自动清洗机清洗消毒。采用目测检查法(四倍带光源放大镜)、腺苷三磷酸(ATP)生物荧光快速检测法进行检测,计算清洗质量不合格的返洗率,比较两组的清洗消毒操作平均耗时。结果观察组的目测检查法返洗率低于对照组,观察组的ATP生物荧光检测返洗率低于对照组,差异有统计学意义(P<0.05)。观察组清洗消毒平均耗时短于对照组,差异有统计学意义(P<0.05)。结论蒸汽清洗机清洗消毒达芬奇机器人手术臂效果比手工刷洗清洗消毒效果更为理想,可节约大量清洗消毒时间,有效节约稀有医疗资源。 展开更多
关键词 达芬奇机器人手术臂 蒸汽清洗机 清洗消毒 返洗率 效果观察
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反冲洗对4种换炭模式下生物活性炭层生物量和水质指标的影响
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作者 方芳 《净水技术》 CAS 2024年第2期190-197,共8页
以水厂砂滤池出水作为生物活性炭柱的反冲洗水,研究了4种换炭模式下反冲洗前后炭层中生物量和出水水质指标的变化情况。结果表明,旧炭(已经运行使用3年的颗粒炭)的装填比例对炭层中生物量和出水水质指标均有不同程度的影响。通常情况下... 以水厂砂滤池出水作为生物活性炭柱的反冲洗水,研究了4种换炭模式下反冲洗前后炭层中生物量和出水水质指标的变化情况。结果表明,旧炭(已经运行使用3年的颗粒炭)的装填比例对炭层中生物量和出水水质指标均有不同程度的影响。通常情况下,全新炭柱上的生物量略高于旧炭,但反冲洗后旧炭比例高的炭柱生物量损失率更低。气水先后反冲洗后总生物量的损失率比单独水冲后总生物量的损失大,但附着生物量的损失基本不变,说明生物活性炭池可尝试使用单独水反冲洗。除高锰酸盐指数(COD_(Mn))变化不明显外,紫外吸光度(UV_(254))、可溶性有机碳(DOC)、生物可降解溶解性有机碳(BDOC)、生物不可降解溶解性有机碳(NBDOC)和三卤甲烷生成潜能(THMFP)的去除率在反冲洗后均有不同程度的上升。因此,反冲洗有利有弊,它既能冲刷掉部分附着在活性炭上的生物膜,对生物的冲刷力较强,同时又能恢复活性炭的吸附能力,使有机物的去除效果增强。反冲洗对填装精制新炭的4#炭柱炭层的吸附容量的恢复力最强,但其生物量的损失率却最大,说明相对于填装粗制新炭的3#炭柱,4#炭柱上的生物系统抵抗水力冲刷能力相对较弱,因此,精制或粗制炭的选择应根据活性炭池是主要发挥其吸附能力还是生物降解能力的需要进行。 展开更多
关键词 生物活性炭池 反冲洗 生物量 出水水质 三卤甲烷生成潜能(THMFP) 换炭
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全国英语阅读大赛对英语教学的反拨效应研究
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作者 朱之红 《石家庄铁路职业技术学院学报》 2024年第1期74-78,共5页
语言测试对语言教学和学习具有促进作用。本研究在阐释反拨效应基本原理的基础上,对全国英语阅读大赛进行分析,探讨该赛事对大学英语教学的正面反拨效应和启示,重点研究大赛对教学内容的调整、教学模式的创新以及教学评价体系的影响。... 语言测试对语言教学和学习具有促进作用。本研究在阐释反拨效应基本原理的基础上,对全国英语阅读大赛进行分析,探讨该赛事对大学英语教学的正面反拨效应和启示,重点研究大赛对教学内容的调整、教学模式的创新以及教学评价体系的影响。旨在顺应大学英语教学改革的时代潮流,提升大学英语教学效果。 展开更多
关键词 全国英语阅读大赛 反拨效应 大学英语教学
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基于PLC的滤站自动控制系统设计
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作者 南丽霞 《现代制造技术与装备》 2024年第1期179-181,共3页
针对滤站的污水处理流程,设计基于可编程逻辑控制器(Programmable Logic Controller,PLC)的滤站自动控制系统,并详细阐述该系统的硬件设计、软件设计。通过应用自动控制系统,滤站能够自动完成污水处理流程,缩短人工时间,提高工作效率。
关键词 可编程逻辑控制器(PLC) 滤站 自动控制系统 过滤 反洗
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泵前无压网式过滤器水力性能试验及研究
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作者 雷辰宇 刘贞姬 +3 位作者 宗全利 杨昊 龙洋娟 陆辰 《灌溉排水学报》 CAS CSCD 2024年第6期68-75,共8页
【目的】探究不同灌溉水源及反清洗装置参数对一种新型无压网式过滤器水力性能的影响。【方法】以一种无压网式过滤器为研究对象,利用多因素方差分析探究在过滤流量为120~160 m^(3)/h、颗粒质量浓度为0.2~0.8g/L以及反清洗装置的反冲洗... 【目的】探究不同灌溉水源及反清洗装置参数对一种新型无压网式过滤器水力性能的影响。【方法】以一种无压网式过滤器为研究对象,利用多因素方差分析探究在过滤流量为120~160 m^(3)/h、颗粒质量浓度为0.2~0.8g/L以及反清洗装置的反冲洗流量为1~20 m^(3)/h、滤筒转速为1~4r/min梯度下的最终水头损失以及过滤器能量损耗的影响因素贡献度。【结果】(1)不同工况下,颗粒质量浓度对无压网式过滤器的水力性能影响效应极低,贡献度仅为0.0108,过滤流量项比初始含沙量项贡献度大于159%;(2)利用Quadratic模型对一般的回归分析修正较好,模型残差值为0.8044,远高于其他模型,调整R2为0.9861;(3)当过滤流量为120.198 m^(3)/h,滤筒转速为1.112 r/min,自清洗流量为19.934 m^(3)/h,满足能量损失最小为16.024k Pa。【结论】Quadratic水力性能模型的预测能力能较好的符合试验值,通过优选最佳值,可以使能量损失达到最小化的目标,满足实际应用。 展开更多
关键词 网式过滤器 无压过滤器 水力性能 反冲洗 多因素方差检验
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Simulation of Two-Phase Flowback Phenomena in Shale Gas Wells
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作者 Yongwei Duan Zhaopeng Zhu +2 位作者 Hui He Gaoliang Xuan Xuemeng Yu 《Fluid Dynamics & Materials Processing》 EI 2024年第2期349-364,共16页
The gas-water two-phaseflow occurring as a result of fracturingfluidflowback phenomena is known to impact significantly the productivity of shale gas well.In this work,this two-phaseflow has been simulated in the framework... The gas-water two-phaseflow occurring as a result of fracturingfluidflowback phenomena is known to impact significantly the productivity of shale gas well.In this work,this two-phaseflow has been simulated in the framework of a hybrid approach partially relying on the embedded discrete fracture model(EDFM).This model assumes the region outside the stimulated reservoir volume(SRV)as a single-medium while the SRV region itself is described using a double-medium strategy which can account for thefluid exchange between the matrix and the micro-fractures.The shale gas adsorption,desorption,diffusion,gas slippage effect,fracture stress sensitivity,and capillary imbibition have been considered.The shale gas production,pore pressure distribution and water saturation distribution in the reservoir have been simulated.The influences of hydraulic fracture geometry and nonorthogonal hydraulic fractures on gas production have been determined and discussed accordingly.The simulation results show that the daily gas production has an upward and downward trend due to the presence of a large amount of fracturingfluid in the reservoir around the hydraulic fracture.The smaller the angle between the hydraulic fracture and the wellbore,the faster the daily production of shale gas wells decreases,and the lower the cumulative production.Nonplanar fractures can increase the control volume of hydraulic fractures and improve the production of shale gas wells. 展开更多
关键词 Shale gas fracturingfluid backflow the stimulated reservoir volume gas-water two-phase production
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Backwash Effects of Language Testing in EFL Classrooms
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作者 赵秦岭 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2002年第S3期100-105,共6页
The article presents some major researches concerning the concept of backwash effect of language testing; analyses both the positive and negative effects and their implications in EFL classrooms; then provides some su... The article presents some major researches concerning the concept of backwash effect of language testing; analyses both the positive and negative effects and their implications in EFL classrooms; then provides some suggested ways to be followed when creating positive backwash effects on teaching and learning. 展开更多
关键词 backwash EFFECT positive/beneficial negative/harmful EFL CLASSROOMS
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Microscopic experiment on efficient construction of underground gas storages converted from water-invaded gas reservoirs
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作者 JIANG Tongwen QI Huan +4 位作者 WANG Zhengmao LI Yiqiang WANG Jinfang LIU Zheyu CAO Jinxin 《Petroleum Exploration and Development》 SCIE 2024年第1期203-212,共10页
Based on the microfluidic technology,a microscopic visualization model was used to simulate the gas injection process in the initial construction stage and the bottom water invasion/gas injection process in the cyclic... Based on the microfluidic technology,a microscopic visualization model was used to simulate the gas injection process in the initial construction stage and the bottom water invasion/gas injection process in the cyclical injection-production stage of the underground gas storage(UGS)rebuilt from water-invaded gas reservoirs.Through analysis of the gas-liquid contact stabilization mechanism,flow and occurrence,the optimal control method for lifecycle efficient operation of UGS was explored.The results show that in the initial construction stage of UGS,the action of gravity should be fully utilized by regulating the gas injection rate,so as to ensure the macroscopically stable migration of the gas-liquid contact,and greatly improve the gas sweeping capacity,providing a large pore space for gas storage in the subsequent cyclical injection-production stage.In the cyclical injection-production stage of UGS,a constant gas storage and production rate leads to a low pore space utilization.Gradually increasing the gas storage and production rate,that is,transitioning from small volume to large volume,can continuously break the hydraulic equilibrium of the remaining fluid in the porous media,which then expands the pore space and flow channels.This is conducive to the expansion of UGS capacity and efficiency for purpose of peak shaving and supply guarantee. 展开更多
关键词 water-invaded gas-reservoir underground gas storage cyclical injection-production gas-water contact gas storage and production rate UGS capacity expansion control method
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核桃壳过滤器滤料漏失分析及应对策略
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作者 范勇强 路立杰 《化工管理》 2024年第20期136-138,共3页
海上某平台是注水开发油田,且多为高含水油井。随着调整井作业、换大泵等提产措施实行,生产水处理量逐年增加,而核桃壳过滤器作为水处理中最后一级设备,对水质达标具有重要作用。然而,近期在下游水处理系统过程中发现较多核桃壳滤料,持... 海上某平台是注水开发油田,且多为高含水油井。随着调整井作业、换大泵等提产措施实行,生产水处理量逐年增加,而核桃壳过滤器作为水处理中最后一级设备,对水质达标具有重要作用。然而,近期在下游水处理系统过程中发现较多核桃壳滤料,持续下去会使滤料漏失更加严重,导致部分油和悬浮物固体吸附在核桃壳表面能力降低,核桃壳反洗频次增加,滤料漏失恶性循环,缩短核桃壳更换周期。针对此问题,现场排查、分析原因及试验论证,通过优化核桃壳反洗流量和反洗力度,将核桃壳滤料漏失量控制在合理范围,有效控制了核桃壳滤料漏失,处理效果明显得到改善,提高再生能力,大大降低了人工时和物资消耗。 展开更多
关键词 滤料漏失 反洗流量 反洗力度 再生能力
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污水处理厂脱氮生物滤池的自动控制方法研究
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作者 项胜 《自动化仪表》 CAS 2024年第6期116-120,共5页
污水处理厂通常在二级生物池后增加高效沉淀池与脱氮生物滤池以进行提标改造,从而达到出水A级排放标准的目的。结合某污水处理厂脱氮生物滤池的工程实践,对滤池的全自动生产控制进行了研究,提出了一种自动控制方法。首先,采用时序顺控... 污水处理厂通常在二级生物池后增加高效沉淀池与脱氮生物滤池以进行提标改造,从而达到出水A级排放标准的目的。结合某污水处理厂脱氮生物滤池的工程实践,对滤池的全自动生产控制进行了研究,提出了一种自动控制方法。首先,采用时序顺控法实现反冲洗控制流程,以满足全工艺自动化要求。其次,采用冒泡法实现优先级选择,解决了控制模式单一的问题。最后,设计了滤池构筑物三维图作为终端界面辅助,增强了上位机系统的可读性。该方法在传统的自控方案上作了一定的优化,使滤池可在多种控制模式下运行,达到全自动与可视化运行的水平。该方法不仅可以为水厂运营减少人力成本,还可以为其他滤池模型的自控专业与工艺研究人员提供参考。 展开更多
关键词 污水厂 提标改造 脱氮生物滤池 反冲洗 控制策略 优先级
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反洗系统投用对芳烃联合装置的影响
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作者 王一帆 《山西化工》 CAS 2024年第5期149-151,共3页
某石化公司芳烃联合装置采用吸附分离工艺生产对二甲苯(PX)。自2014年吸附塔换剂投用至2020年期间,在带来巨大经济效益的同时,伴随着吸附剂寿命老化,性能下降等问题,导致PX纯度持续恶化,PX收率持续降低。为改善PX纯度,提高PX收率,经公... 某石化公司芳烃联合装置采用吸附分离工艺生产对二甲苯(PX)。自2014年吸附塔换剂投用至2020年期间,在带来巨大经济效益的同时,伴随着吸附剂寿命老化,性能下降等问题,导致PX纯度持续恶化,PX收率持续降低。为改善PX纯度,提高PX收率,经公司研究决定,投用吸附塔反洗系统。自反洗系统投用后PX纯度由99.72%上升至99.78%,PX收率由93.5%上升至97.6%,经核算反洗系统投用后年增效约4399万元。 展开更多
关键词 反洗系统 PX纯度 PX收率
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煤砂双层滤料滤池气水反冲洗参数探究及应用
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作者 张欢 刘霄鹏 +3 位作者 王栋 谷雷严 杨建华 冯文 《净水技术》 CAS 2024年第3期68-75,116,共9页
为解决济阳某10万m^(3)/d水厂煤砂双层滤料滤池反冲洗不彻底、滤料流失、混层等问题,对滤池进行了水反冲流体力学(CFD)模拟,指导水冲阶段反冲洗强度的选取,并在现场进行了中试试验。试验结果表明:采用气水反冲洗模式,当气冲阶段qs=17.0 ... 为解决济阳某10万m^(3)/d水厂煤砂双层滤料滤池反冲洗不彻底、滤料流失、混层等问题,对滤池进行了水反冲流体力学(CFD)模拟,指导水冲阶段反冲洗强度的选取,并在现场进行了中试试验。试验结果表明:采用气水反冲洗模式,当气冲阶段qs=17.0 L/(m^(2)·s)、t=3 min时;水冲阶段,梯度提升水冲强度,在q_(w1)=4.5 L/(m^(2)·s)、t_(1)=2 min,q_(w2)=7.0 L/(m^(2)·s)、t_(2)=3 min,q_(w3)=17.5 L/(m^(2)·s)、t_(3)=3 min时,反冲洗后滤料含泥量可控制在0.1%以下,并可恢复滤料混层。将最优参数在工程现场应用后,有效解决水厂反冲洗问题,延长过滤周期,滤池反冲洗年耗水量减少192720 m^(3)。 展开更多
关键词 煤砂双层滤料滤池 CFD 模拟 气水反冲洗 含泥量 混层
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