【作者】 张锐；

【导师】 邓宇； 朱孟府；

【作者基本信息】 天津科技大学 ， 化学工程（专业学位）， 2017， 硕士

【摘要】 水力空化因其在发生过程中产生巨大的能量,近年来成为众多水处理学者的研究重点,然而这种技术并不成熟还没有被工厂大规模使用,因此需要研究水力空化特性,为将来应用奠定基础。为探究水力空化应用前景,本文主要通过FLUENT流场模拟、亚甲基蓝降解、纳米羟基磷灰石分散研究了水力空化的氧化特性与分散特性。基于FLUENT软件K-ε模型对孔板水力空化反应器中流体流动进行数值模拟,选择孔隙率与孔数相同排布不同、孔数与排布相同孔隙率不同、孔隙率相同孔数不同三种规律的系列孔板模拟分析初步得出结论:所做系列孔板空化器中,圆环排布比交错排布、十字排布的孔板空化器的空化效果要好;相同排布的孔板孔径小的孔板空化器空化效果要好;相同孔隙率孔数多的孔板空化器空化效果要好。水力空化降解有机物特性采用亚甲基蓝为水中模拟污染物,研究了操作条件与孔板结构对亚甲基蓝降解效果的影响,其中孔板结构采用了与模拟部分相同的规律,除了讨论水力空化氧化降解有机物特性外,目的还在于对模拟部分进行实验验证。通过实验数据分析得出以下规律,亚甲基蓝降解率随着初始浓度的增加而降低,随着溶液温度与入口压力增加有先增大后减小的趋势,随着空化时间的延长不断增加,最终趋于平缓。水力空化技术降解亚甲基蓝最佳操作条件为:入口压力0.35 MPa、时间4.0 h、MB初始浓度0.53 mg·L-1、溶液温度35 ℃,最佳工艺下MB降解率平均值为11.9%。水力空化降解有机物符合一级动力学反应模型。将最佳孔板空化器进行应用性研究,对水中纳米羟基磷灰石进行分散实验,由Zeta电位仪、SEM分析得知,水力空化-分散剂联合作用对水中纳米羟基磷灰石分散效果较好。水力空化-分散剂分散水中纳米羟基磷灰石最佳工艺为:HA浓度0.50 g·L-1、Nap:HA为10:1、入口压力0.35 MPa、空化时间25 min、空化温度20 ℃。分散后的分散体系剩余沉降率平均为82.0 w%,粒径平均为191.2 nm。更多还原

【Abstract】 Hydraulic cavitation is a new type of water treatment technology in recent years.It is a phase change process of liquid from liquid phase to gas phase.Cavitation growth and collapse in the liquid generated when the local high temperature and pressure,shock waves,high-speed jet and other extreme physical conditions.In the hydraulic machinery,cavitation should be avoided as much as possible,so as to avoid damaging the machinery.However,this kind of characteristic can also make the chemical reaction difficult to be realized under normal conditions.As we are using,the energy released by cavitation exerts a great influence on the chemical physics process Strengthen.However,this technology is not mature enough to be used on a large scale in factories.Therefore,it is necessary to study the characteristics of hydraulic cavitation and lay the foundation for future applications.In order to explore the application prospect of hydraulic cavitation,this paper mainly studied the oxidation and dispersion characteristics of hydraulic cavitation by FLUENT flow field simulation,methylene blue degradation and nano-hydroxyapatite dispersion.Based on the FLUENT software κ-ε model,the numerical simulation of the fluid flow in the orifice hydrodynamic cavitation reactor was conducted.The selected porosity and pore number were the same.The pore numbers were the same with the same arrangement and the same number of pores were different.The series of perforated plate cavitator,the annular arrangement than the staggered arrangement,the cross-arranged perforated plate cavitator cavitation effect is better;the same arrangement of the orifice plate,a small aperture plate cavitator empty the effect is better;the same porosity of the hole plate,the hole number of holes cavitator cavitation better.Hydrodynamic cavitation degradation of organic matter using methylene blue as a simulated pollutant in water,the operating conditions and the orifice plate structure on the degradation of methylene blue effect,in which the orifice plate structure with analog part of the same rules,in addition to discuss the hydrodynamic cavitation oxidative degradation of organic matter The purpose of the feature is to experimentally verify the simulation part.The experimental results show that the degradation rate of methylene blue decreases with the increase of the initial concentration,and then increases with the increase of the operating time as the solution temperature and inlet pressure increase first and then decrease,and the increase rate slowing shrieking.The optimum operating conditions for hydrocyanation degradation of methylene blue were as follows:inlet pressure 0.35 MPa,time 4.0 h,MB initial concentration 0.53 mg·L-1 and solution temperature 35 ℃.The average MB degradation rate under the optimum conditions was 11.87%.Hydrodynamic cavitation degradation of organic compounds in line with the first-order kinetic reaction model.The optimum orifice plate cavitator was applied to study the water nano-hydroxyapatite dispersion experiment by Zeta potential analyzer,SEM analysis that the combination of hydrodynamic cavitation-dispersant nano-hydroxyapatite dispersed in water The effect is better.The optimum conditions of hydrodynamic cavitation-dispersant dispersive nano-hydroxyapatite were HA concentration 0.50 g·L-1,Nap:HA 10:1,inlet pressure 0.35 MPa,operating time 25 min and dispersion temperature 20 ℃.The dispersion rate of dispersed system averaged 82.0 w%and the average particle size was 191.2 nm.更多还原