【作者】 杨斌；

【导师】 倪师军；

【作者基本信息】 成都理工大学 ， 地球化学， 2020， 博士

【摘要】 绵远河流域是四川省重要的磷肥和磷化工生产基地,其沿岸分布了多达千余座的工厂企业且该河流穿过了许多人口密集区。上游磷矿开采;中游农业灌溉,磷化肥的生产;下游城镇居民生活污水的排放等等,共同造成了绵远河严重的污染,严重危害着沿河两岸生活的居民的健康,也严重影响着两岸农作物的生长。以上各种工农业污染及生活污染的综合影响加大了河流污染源追溯及污染治理的难度。因此,如何有效地评价绵远河污染状况、污染物污染机理及来源并探索合理的污染治理技术是绵远河地区污染治理的关键问题。本文以国家自然基金项目《富磷水系铀的赋存形态及分配研究》（编号:41373120）为依托,详细测定了河水的理化性质以及TP（总磷）,TN（总氮）的含量,对水系沉积物的污染进行风险评价,测定了河水氢氧同位素地球化学特征,探索了有效提取河水磷酸根的方法,并对磷酸根中氧同位素值进行测定,探究了造成磷酸根氧同位素理论值与实测值差异的影响因素,并应用其对P的来源进行示踪,开发出了废水Pb²⁺去除的新技术。研究结果显示:绵远河水体pH（酸碱性）范围为7.9～8.7,均值8.41,水体偏碱性。水体Ec（电导率）范围为34～81,均值为45.7,水体可溶性盐浓度较高。水体Eh（氧化还原电位）范围为114～213m V,均值为154.2m V,水体Eh值较低。水体Do（溶解氧含量）范围为5.28～9.01ppm,均值为7.85ppm,水质在溶解氧指标上有所提升。水体中的TN含量范围为0.17～10.20mg/L,均值为2.34mg/L,超过国家Ⅲ类水质标准。水体TP含量范围为0.01～0.29mg/L,均值为0.10mg/L。水体属于富营养化水体。水系沉积物Cd的含量范围0.41～1.07 mg/kg,均值为0.60 mg/kg。Pb的含量范围11.8～36.80 mg/kg,均值为17.30 mg/kg。水系沉积物中Cd的单因子污染指数（C_fⁱ）范围为0.91～2.38,均值为1.33,单因子污染程度属于中度。Pb的单因子污染指数（C_fⁱ）范围0.44～1.37,均值为0.65,单因子污染程度属于低度。水系沉积物有效P含量范围3.6～99.8 mg/kg,均值为22.89 mg/kg。水系沉积物Cd的单因子潜在生态风险指数变化范围27.3～71.4,均值为39.8;Pb的单因子潜在生态风险指数变化范围2.2～6.85,均值为3.23。Cd和Pb的单因子潜在生态风险指数最大值均出现在C09号采样点连山镇。同时,连山镇也是水系沉积物Cd单因子潜在生态风险程度较高的镇,而所有采样点水系沉积物Pb单因子潜在生态风险程度均为低度。绵远河河水δD（氘核的绝对变差）的范围为-11.30～-10.36‰,均值为-10.83‰,δ¹⁸O(¹⁸O的绝对变差)的范围为-87.47～-79.07‰,均值为-83.27‰。δD从上游到下游,相对较稳定,而δ¹⁸O从上游到下游,呈现出由高到低再到高的变化特征。水体PO₄^3-中δ¹⁸O测试值范围为9.72‰～20.00‰,均值为20.59‰。从中游到下游,水温逐渐升高,而δ¹⁸O_p值呈现出先升高后降低的趋势,与水温的变化不具有相关性,这在一定程度上说明中游至下游的δ¹⁸O_p值几乎不受水温的影响。微生物作用和水体TP/TN比率是造成水体PO₄^3-中的δ¹⁸O_p理论值与实测值差异的可能因素。由此,可以推测,绵远河的P污染主要来至于四部分:上游是磷矿开采与冶炼;中游是工业企业排放的污水和农业灌溉区磷肥的使用;下游是城镇居民生活污水的排放。本次研究合成了一种新型吸附剂PVP/Fe₃O₄/GO复合材料,其具有良好的水分散性。作为制备的复合材料,用于去除Pb2+具有高度的选择性和高效率,易于重复使用。PVP/Fe₃O₄/GO复合材料处理不同废水样品,Pb²⁺去除率可达90%以上。特别是低含量Pb²⁺污水样品处理后,其中的Pb²⁺离子可进一步降至0.4ppb。因此,该复合材料可应用于水体中低含量Pb²⁺的去除,进一步降低水体Pb污染。更多还原

【Abstract】 The Mianyuan River Basin is an important production base of phosphate fertilizer and chemical industry in Sichuan Province.It has as many as 1000 factories and enterprises along the coast and the river runs through many densely populated areas.Upstream phosphate mining;agricultural irrigation in the middle reaches,the production of phosphorus and fertilizer;the discharge of domestic sewage from downstream urban residents,and so on,have jointly caused serious pollution in the Mianyuan River,seriously endangering the health of residents living on both sides of the river,and also seriously affecting the growth of crops on both sides of the river.The comprehensive influence of all kinds of industrial and agricultural pollution and domestic pollution has increased the difficulty of river pollution source tracing and pollution control.Therefore,how to effectively evaluate the pollution status,mechanism and source of pollution and explore reasonable pollution control technology is the key problem of pollution control in Mianyuan River area.Based on the National Natural Science Foundation project"Phosphorus-rich Water Uranium Occurrence Forms and Distribution Research"（No.41373120）,the physical and chemical properties of river water and the contents of TP（total phosphorus）and TN（total nitrogen）were determined in detail.Risk assessment of pollution of river sediments,determination of the geochemical characteristics of hydrogen and oxygen isotopes in river water,exploration of effective extraction methods for phosphate in river water,determination of oxygen isotope values in phosphates,exploration of factors affecting oxygen isotopes,and their application Traced the source of P and explored a new technology for removing lead ions in wastewater.The results show that:The range of water body pH（acid-base）in Mianyuan River was 7.9～8.7,the mean value was 8.41,and the water body was alkaline.The range of water Ec（conductivity）was 34～81,the mean value was 45.7,and the concentration of soluble salt in water was high.The range of water Eh（redox potential）was 114～213m V,the mean value was154.2m V,and the Eh value of water body was low.The range of water Do（dissolved oxygen content）was 5.28～9.01 ppm,the mean value was 7.85 ppm,and the water quality had improved on the dissolved oxygen index.The range of TN content in water was 0.17～10.20 mg/L,the mean value was 2.34,which exceeded the national class III water quality standard.The range of water TP content was 0.01～0.29 mg/L,and the mean value was 0.10 mg/L.Water body belonged to eutrophic water body.Water system sediment Cd content ranged 0.41～1.07 mg/kg,mean 0.60 mg/kg.Pb content ranged 11.8～36.80 mg/kg,mean 17.30 mg/kg.The pollution index（C_fⁱ）of Cd in water system sediments ranged from 0.91～2.38,with a mean of 1.33,and belonged to moderate pollution.The Pb pollution index（C_fⁱ）ranged from 0.44～1.37,with a mean of 0.65,and belonged to low pollution.The ranged of effective P content in water sediments 3.6～99.8 mg/kg,mean 22.89 mg/kg.The variation range of single factor potential ecological risk index Cd water system sediment was 27.3～71.4,and the mean value was 39.8;the variation range of single factor potential ecological risk index was 2.2～6.85,and the mean value was 3.23.Cd and Pb single-factor potential ecological risk index maximum appeared in Lianshan Town.Meanwhile,Lianshan Town also was a town with high potential ecological risk degree Cd single factor,while the potential ecological risk degree Pb single factor was low in all sampling sites.The range ofδD（absolute variation of deuterium）in the river water of Mianyuan River was-11.30～-10.36‰,and the mean value was-10.83‰.The range ofδ¹⁸O(absolute variation of ¹⁸O)was-87.47～-79.07‰,and the mean value was-83.27‰.δD from upstream to downstream,relatively stable,whileδ¹⁸O from upstream to downstream,showing a change from high to low to high.The range ofδ¹⁸O test values in water PO₄^3-was 9.72‰～20.00‰,and the mean value was 20.59‰.From the middle reaches to the downstream,the water temperature increased gradually,while theδ¹⁸O_p value showed the trend of first rising and then decreasing,which was not related to the change of water temperature,which indicated that theδ¹⁸O_p value from the middle reaches to the downstream was almost unaffected by the water temperature.The effect of microbial action on theδ¹⁸O_p value in water PO₄^3-was more intense.The higher theδ¹⁸O_p value in water PO₄^3-,the larger the water TP/TN ratio,the greater theδ¹⁸O_p value.The O isotope exchanged between river PO₄^3-and H₂O did not reach equilibrium.The above all revealed that theδ¹⁸O_p values of PO₄^3-in the water body retained P original source information.From this,it could be inferred that the P pollution of the Mianyuan River came mainly to four parts:the upper reaches were phosphate mining and smelting;the middle reaches were the sewage discharged by industrial enterprises and the use of phosphate fertilizer in agricultural irrigation areas;and the lower reaches were the discharge of domestic sewage from urban residents.A novel adsorbent PVP/Fe₃O₄/GO composite with good water dispersion was synthesized in this study.As the as-prepared composited for removal of Pb²⁺with high selectivity and efficiency and easy reuse.Furthermore,it could selectively removed Pb²⁺.In the presence of coexisting metal ions with higher separation factors the Pb²⁺removal rate could reach more than 90%when PVP/Fe₃O₄/GO the composited materials to treat different wastewater samples.The Pb²⁺ions in the river could be reduced to 0.4ppb,after sample treatment.Therefore,the composite material can be used to deal with the removal of water Pb²⁺in acid water and reduce the pollution Pb water bodies.更多还原