絮凝-活性炭-过氧化氢复合工艺处理醇酸废水

本文采用絮凝-活性炭-过氧化氢组合工艺处理醇酸废水,探讨了不同处理技术的最佳工艺条件和处理效果。结果表明,絮凝剂添加量0.5%、静置沉淀24h时絮凝效果最好。在反应温度60℃、反应时间4h、反应pH值为4、活性炭添加量2%、过氧化氢添加量6%时氧化条件最佳。在此条件下,醇酸废水COD去除率为82.33%,脱色率为93.75%。

醇酸树脂生产废水厌氧生物降解研究

针对醇酸树脂生产废水COD高、成分复杂等问题,以螺旋对称流厌氧反应器(SSSAB)为载体,对比研究了物化预处理对SSSAB处理醇酸树脂生产废水效果的影响,考察是否可通过使用SSSAB省略传统预处理,并确定了废水中有机物的种类。结果表明:SSSAB对经物化预处理的水样的厌氧处理效果优于未经物化预处理的水样,但两者均达到了良好的降解效果。未经物化预处理的水样在平均进水COD为9133 mg/L,水力停留时间(HRT)为1.25 d,有机负荷(OLR)为7.2 kg/(m^(3)·d)(以COD计,下同)时,SSSAB对COD的去除率为89.36%;经物化预处理的水样在平均进水COD为6399 mg/L,HRT=0.83 d,OLR=7.56 kg/(m^(3)·d)时,SSSAB对COD的去除率为94.62%。GC-MS分析表明醇酸树脂生产废水主要有机组分为对二甲苯和邻二甲苯,峰面积占总出峰面积的比例分别为46.57%和30.42%;经物化预处理后,主要有机组分为苯乙酮和苯酚,峰面积占比例分别为80.49%和12.38%;这4种有机组分在厌氧降解后均未检出,表明SSSAB具有较好的有机物降解效果,并且使用SSSAB反应器在一定程度上可以省略传统预处理。

Recycling and depolymerization of waste polyethylene terephthalate bottles by alcohol alkali hydrolysis

In this work,a novel alcohol alkali hydrolysis method was explored for the preparation of terephthalic acid(TPA)from waste polyethylene terephthalate(PET).First,a series of single factor experiments on the depolymerization rate of waste PET bottles and the yield of TPA were conducted to determine the optimized experimental conditions,in terms of reaction time,reaction temperature,dosage of ethylene glycol and sodium bicarbonate,amount of distilled water and stirring rate.Then IR spectra and elemental analysis were carried out for the characterization of obtained product.Under optimal experimental conditions,over 98%PET can be depolymerized into the target product(TPA)and the purity and yield of TPA are over 97%and 94%,respectively.Both the experimental and analytical results support a feasible process for the preparation of TPA from waste PET.It is expected that this alcohol alkali hydrolysis method can promise an effective way for the sustainable recycling of waste PET.