摘要
为探索硫酸钾肥对黄河水泥沙在静止状态下沉降的影响,以硫酸钾浓度和泥沙粒径为参数,用移液管法研究了5种硫酸钾浓度和4种粒径范围段(<100,50~100,34~50,<34μm)黄河泥沙的沉降过程,探讨不同硫酸钾浓度对细颗粒泥沙沉降絮凝的影响。结果表明:硫酸钾浓度越大,含沙量下降越快,泥沙沉降速度越大,初始粒径<100μm,当硫酸钾浓度分别为0,2.86,7,14mmol/L时,沉降30min后相对含沙量分别为35.35%,30.75%,27.02%,14.00%,中值沉速ω50分别为1.55,3.00,3.91,4.93cm/min;泥沙初始粒径越小,硫酸钾促进絮凝沉降的作用越明显,<34μm的泥沙受硫酸钾影响最大,当硫酸钾浓度从0增大到60mmol/L时,初始粒径为<34μm的泥沙絮凝后的中值沉降速度从1.38cm/min增加到8.53cm/min,增加518.12%,初始粒径为34~50μm的泥沙絮凝后的中值沉降速度从6.29cm/min增加到8.43cm/min,增加34.02%,初始粒径为50~100μm的泥沙中值沉降速度从7.12cm/min增加到7.59cm/min,增加6.60%;泥沙粒径越小,硫酸钾浓度越大,对絮凝后中值粒径的影响越大,当硫酸钾浓度从0增大到60mmol/L时,初始粒径为50~100μm的泥沙絮凝后中值粒径与硫酸钾浓度之间无明显规律,不同处理间无显著差异,硫酸钾基本对该粒径段泥沙絮凝沉降没有影响,初始粒径为34~50μm的泥沙絮凝后的中值粒径从38.8μm增加到41.0μm,增大5.76%,初始粒径<34μm的泥沙絮凝后中值粒径从15.7μm增加到21.6μm,增大37.82%;絮凝后沉降泥沙中小粒径颗粒相对含量减少,大粒径颗粒相对含量增加,最大粒径变大,泥沙初始粒径为<34μm、硫酸钾浓度为60mmol/L处理絮凝后最大粒径为200μm。研究成果为解决水肥一体化过程中的滴灌堵塞问题提供了参考。
There are many factors affecting the flocculation and sedimentation of fine sediments.The objective of this study was to explore the effect of potassium sulfate fertilizer on the sedimentation of the static Yellow River water.Taking potassium sulfate concentration and sediment particle size as parameters,five potassium sulfate concentrations and four particle size ranges(<100,50~100,34~50,and<34μm)of Yellow River sediment were studied by pipette method.In the sedimentation process,the effects of different potassium sulfate concentrations on the flocculation of fine sediments were discussed.The results showed that the higher the concentrations of potassium sulfate were,the faster the sediment concentration decreased,the higher the sedimentation velocity was.The initial particle size was<100μm,and when the concentrations of potassium sulfate were 0,2.86,7,14 mmol/L,the sedimentation time was 30 min,the relative sediment concentrations were 35.35%,30.75%,27.02%,14.00%,and the median sedimentation speedω50 was 1.55,3.00,3.91 and 4.93 cm/min,respectively.The smaller the initial sediment particle size was,the more obvious the promotion effect of potassium sulfate on flocculation sedimentation was.The sediment of<34μm sediment was most affected by potassium sulfate.When the potassium sulfate concentration increased from 0 to 60 mmol/L,the median sedimentation velocity after flocculation with initial particle size<34μm increased from 1.38 cm/min to 8.53 cm/min,increased by 518.12%,and the median sedimentation velocity after flocculation with initial particle size of 34~50μm increased from 6.29 cm/min to 8.43 cm/min,with an increase of 34.02%.The median sedimentation velocity of sediment from 50 to 100μm increased from 7.12 cm/min to 7.59 cm/min,with an increase of 6.60%.The smaller particle size of sediment and the greater concentration of potassium sulfate gave the greater influence on the median particle size after flocculation.When the concentrations of potassium sulfate increased from 0 to 60 mmol/L,there was
作者
李学凯
牛文全
张文倩
王亚琼
温圣林
杨小坤
LI Xuekai;NIU Wenquan;ZHANG Wenqian;WANG Yaqiong;WEN Shenglin;YANG Xiaokun(Key Laboratory of Agricultural soil and Water Engineering in Arid and Semiarid Areas,Ministry of Education,Water and Architecture Engineering,Northwest A&F University,Yangling,Shaanxi 712100)
出处
《水土保持学报》
CSCD
北大核心
2019年第4期140-146,227,共8页
Journal of Soil and Water Conservation
基金
国家重点研发计划项目(2016YFC0400202)
国家自然科学基金项目(51679205)
宁夏重点研发计划项目(2018BBF02006)
杨凌示范区科技计划项目(2018GY-08)
关键词
硫酸钾
静水沉降
黄河泥沙
粒径级配
potassium sulphate
hydrostatic sedimentation
Yellow River sediment
particle size grading
