摘要
以NaOH作碱源,采用水热晶化法将粉煤灰转化成沸石。通过改变灼烧温度、NaOH浓度、液固比、晶化时间,考察合成条件对合成沸石阳离子交换容量的影响,并应用于焦化废水A/O出水的处理。结果表明:在灼烧温度为700℃、NaOH浓度为1 mol/L、液固比为5∶1 mL/g、晶化时间为36 h条件下,合成沸石的阳离子交换容量最高为167 mmol/100 g,是原粉煤灰的12.8倍,高于天然沸石的160 mmol/100 g;合成沸石处理焦化废水A/O出水的最佳条件是反应时间为1 h,沸石投加量为2 g/100 mL,pH值为6.0～9.0,此时NH3-N、COD去除率及出水质量浓度分别为46.7%、17.6%和62.6、197.8 mg/L,合成沸石对NH3-N的吸附符合Freundlich吸附等温式。
With NaOH as alkaline source, the coal fly ash could be transformed into zeolite by hydrothermal crystallization process. Through changing incandesce temperature, concentration of NaOH, liquid-solid ratio, crystallization time, the influence of synthesis condition on the cation exchange capacity of the synthesized zeolite was investigated, and then, the said zeolite was used to treat effluent from A/O coking wastewater treatment system. The results showed that： under the condition that, the incandesce temperature was 700℃, the mass concentration of NaOH was 1 mol/L, the liquid-solid ratio was 5 ： 1 mgL/g, the crystallization time was 36 h, the maximal cation exchange capacity of the synthesized zeolite was 167 mmol/100 g, which was 12.8 times the cation exchange capacity of the raw coal fly ash, higher than the natural zeolite（160 mmol/100 g）; the optimal condition for the synthesized zeolite treating effluent from A/O coking wastewater treatment system was： the reaction time was 1 h, the dosage of the said zeolite was 2 g/100 mL, the pH value was 6.0 - 9.0. Under the above condition, the removal rate of NH3-N and COD, the effluent concentration of the two were 46.7%, 17.6%, 62.6, 197.8 mg/L respectively, the adsoption of the synthesized zeolite on NH3-N fitted the Freundlich isotherm.
出处
《工业用水与废水》
CAS
2009年第2期68-71,共4页
Industrial Water & Wastewater
关键词
粉煤灰
沸石
水热晶化
焦化废水
coal fly ash
zeolite
hydrothermal crystallization
coking wastewater
