【作者】 顾锡慧；

【导师】 周集体；

【作者基本信息】 大连理工大学 ， 环境工程， 2008， 博士

【摘要】 高盐高浓度有机废水的排放带来十分严重的环境污染，由于它不仅含有高浓度的盐分，同时还含有大量有毒、难降解的溶解性有机物，传统处理工艺均存在一些难于克服的缺点和局限性。近年来，我国在树脂法处理高浓度有机化工废水及资源化技术的开发和应用方面取得了较大进展，各种新型吸附剂的合成和应用已成为环保领域十分活跃的研究方向之一。在此背景下，本文利用树脂对有机物的选择吸附性及容易再生的特点，提出了针对高盐有机废水的一种新型处理方法——大孔吸附树脂吸附分离-生物再生法。本文针对芳香胺和酚类化合物的物理和化学特性，选用西安蓝深交换吸附材料有限责任公司生产的XDA-1大孔吸附树脂，主要从吸附等温线、热力学和动力学等方面就高盐苯胺／苯酚废水在XDA-1上的吸附作用及传质过程进行了研究，并考察了生物法对吸附饱和的树脂再生的可行性和稳定性，以期为大孔吸附树脂在高盐有机废水的治理应用中提供一定理论基础。本文主要研究内容与结果如下：1．大孔树脂XDA-1可有效分离苯胺／苯酚和NaCl，溶液pH和初始苯胺浓度的增大均可强化苯胺的吸附去除，吸附质以分子形态为主存在的溶液pH范围有利于吸附。分析大孔树脂XDA-1吸附法处理高盐苯胺／苯酚废水的过程发现：XDA-1的吸附容量与溶液的含盐量呈正相关。Freundlich吸附等温线方程可以很好地解释此吸附过程，苯胺和苯酚在XDA-1表面上是优惠吸附过程，K_F变化说明吸附属于放热过程；在一定温度下，K_F随着NaCl含量的提高而增大，说明苯胺和苯酚的吸附量与NaCl含量呈正相关；热力学研究表明苯胺和苯酚在XDA-1表面的吸附为焓推动的自发的物理吸附过程，吸附的主要作用力为范德华力、氢键、偶极间力及疏水作用。动力学研究表明苯胺和苯酚在XDA-1上的吸附符合准二级动力学吸附速率方程，吸附速率常数随着溶液盐度增大而增大。苯胺和苯酚吸附速率与溶液盐度分别符合下列关系：苯胺：q_t=(18．85·C_NaCl+503．83)·exp(-(0.082·C_NaCl+0．1577)/t)苯酚：q_t=(83．58·C_NaCl+23．35)·exp(18．31·C_NaCl-5．90/t)苯胺和苯酚在XDA-1上内扩散过程为吸附速率主要控制步骤，同时还受颗粒外扩散的影响。吸附初始阶段大孔和中孔的内扩散系数稍低于吸附后期平衡阶段。2．生物再生过程包括物理解吸和生物降解两部分，苯胺解吸速率（V_d）与XDA-1的平均剩余吸附容量（Qr）有关，其数学关系满足V_d=0．2697exp（0．0195Qr）。综合物理解吸和生物降解两方面因素，确定最适的饱和树脂生物再生条件是在30℃、pH=7．0、固液比为1：400 g/mL和再生时间120 h。采用大孔树脂吸附-生物再生法处理高盐苯胺废水效果稳定，六次吸附／再生循环过程中，NaCl的分离效率和树脂生物再生效率分别稳定在98．3％和92．3％以上。3．苯酚解吸速率（V_d）与XDA-1的平均剩余吸附容量（Qr）有关，其数学关系满足：综合物理解吸和生物降解两方面因素，确定最适的饱和树脂生物再生条件是在30℃、pH=7．0、固液比为1：1500g/mL和再生时间48 h。采用大孔树脂吸附-生物再生法处理高盐苯酚废水效果稳定，六次吸附／再生循环过程中，XDA-1对NaCl的分离效率均为98％以上，生物再生效率维持在81％以上。4．生物法再生饱和吸附树脂是可行的，但再生树脂的比表面积、总孔容积并不能得到完全恢复，平均孔径也有所增加。吸附剂的吸附性能与表面结构特性密切相关，再生XDA-1吸附容量的下降正是这些吸附剂表面结构的变化的宏观体现。吸附质残留和生物附着均是导致大孔吸附树脂XDA-1生物再生不完全并有所下降的原因。5．饱和吸附苯胺／苯酚的大孔吸附树脂XDA-1的生物再生机理符合浓度梯度假说。在前人研究的基础上，本研究对处理高盐苯胺／苯酚废水的大孔吸附树脂的生物再生过程的数学描述进行简化。利用这两个处理体系的生物再生数据进行模型验证，发现此模型能较好的预测饱和吸附苯胺／苯酚的XDA-1的生物再生过程。本研究为实现芳香胺及酚类高盐有机废水的处理提供了一条可行而有效途径。更多还原

【Abstract】 The discharge of high salinity and high organic concentration wastewater causes serious environmental pollution. As it contains not only high concentration of salinity, but also a great quantity of solvable organic compounds, which are toxic and hard for degradation, the performances of conventional processes were always uncompetitive and unstable. Recently, the polymeric adsorption resin has been widely used in the treatment of organic wastewater. The synthesis and application of new kinds of adsorbent is one of the most active research focuses in the area of environmental protection. Thus, a new treatment process which integrated the polymeric resin adsorption separation and biological regeneration was established for treating hyper-saline organic wastewater. Resin XDA-1 offered by Xi’an Lanshen Special Resins Co. Ltd. （China） was selected for aromatic amine and phenolic compounds removal according their physical and chemical properties. In this study, the adsorption characteristic, mass transfer process and mechanism of the combined process were investigated. The objective of this work is to validate the efficiency and stability of the use of a combined adsorption/bio-regeneration method for aniline/phenol treatment from hyper-saline effluents. The following works are carried out main experimental results and conclusions are as follows in this dissertation:1. The results show that aniline or phenol can be effectively separated from NaCl by resin XDA-1 adsorption. It was found that decreasing temperatures and increasing initial aniline concentration are beneficial for aniline and phenol adsorption. And adsorption is enhanced in pH values in which aniline or phenol mainly present as molar phase. The isotherm data of aniline and phenol adsorption fitted well with Freundlich equation. The adsorption of aniline and phenol onto XDA-1 were proved to be an exothemic process according to the changing trend of K_F. Parameter K_F, indicated the relative sorption capacity, increases with increasing ionic strength or decreasing temperature. The thermodynamic parameters indicate a spontaneous exothermic physic-sorption process, and the main adsorption forces are the van der Walls, hydrogen bonds, and hydrophobic interactions. Adsorption kinetics follows pseudo-second-order rate expression. It was demonstrated that the presence of salt enhances the adsorption removal of aniline and phenol from aqueous. The strong influence of salts on the structure of water and water solubility of the hydrophobic adsorbate accelerate the aniline and phenol adsorption onto the surface of XDA-1 resin. It was shown that adsorption capacity of XDA-1 was enhanced with the increase of salinity, and the relationships between instantaneous adsorption of aniline or phenol and salinity could be expressed as follows,Aniline:Q_t=(18．85·C_NaCl+503．83)·exp(-0.082·C_NaCl+0．1577/t)Phenol:q_t=(83．58·C_NaCl+23．35)·exp(18．31·C_NaCl-5．90/t)Results indicate that the intra-particle diffusion rate is the main control step of aniline or phenol adsorption, and the adsorption process is also affected by external diffusion. The intra-particle diffusion coefficients of macropore and mesopore at the adsorption initial phase are low than that of micropore.2. Bio-regeneraton process contains physical desorption process and biodegradation process. It was indicated that the residual adsorption capacity of aniline on XDA-1 （Qr） could be well correlated with the desorption velocity （V_d）. The relation can be expressed as follows,Comprehensive considering these two factors, the optimum conditions for bioregeneration of aniline exhausted XDA-1 resin were settled as 30℃, pH=7, the ratio of solid mass and aqueous solution volume being 1/400 g/mL, and 120 h. Under the optimum conditions for bio-regeneration, the exhausted XDA-1 can be recovered successfully. The adsorption and bio-regeneration process repeated for up to six cycles, the PR and NaCl SE of XDA-1 remained 92.3% and 98.3%, respectively.3. It was indicated that the residual adsorption capacity of phenol on XDA-1 （Qr） could be well correlated with the desorption velocity （V_d）. The relation can be expressed as follows,Comprehensive considering effect factors of physical desorption and biodegradation process, the optimum conditions for bioregeneration of phenolic exhausted XDA-1 resin were settled as 30℃, pH=7, the ratio of solid mass and aqueous solution volume being 1/1500 g/mL, and 48 h. Under the optimum conditions for bio-regeneration, the exhausted XDA-1 can be recovered successfully. The adsorption and bio-regeneration process repeated for up to six cycles, the PR and NaCl SE of XDA-1 remained above 81% and 98%, respectively.4. It is feasible for renew exhausted adsorption resin by bio-regeneration method. However, the specific surface area and total pore volume of samples can not be recovered completely with this mothod. And the average pore diameter increases after bio-regeneration process. There is a close relations between adsorption performance and the surface and structure characteristic of adsorbents. The decreased adsorption capacity of regenerated XDA-1 resin is the macroscopical phenomon of these changes of surface and structure characteristic of adsorbents. And the remaining of adsorbate and the attachment of microorganisms on XDA-1 surface are two reasons resulted in the loss of PR.5. Bio-regeneration of XDA-1 resin loaded with aniline/phenol is due to a concentration gradient. A simplified model was developed to describe the bio-regeneration process of exhausted adsorption resin. It is demonstrate that this model is very good to predict the bio-regeneration process.This research provided an efficient and practical method for the treatment of hyper-saline wastewater loaded with aromatic amine or phenolic compounds.更多还原