污泥是污水处理过程中的副产物,含有重金属、有机污染物、病原菌和寄生虫卵等有毒有害物质.为了明确堆腐对污泥中腐殖酸的影响,本研究在污泥∶草炭∶稻草=3∶1∶2(干重比)和55％含水量条件下,开展了为期30 d的堆腐试验.采用紫外光谱仪、红外光谱仪等仪器手段,研究了污泥堆腐过程中腐殖酸组成及结构变化.结果表明,污泥堆腐过程中腐殖酸含碳量呈先下降后上升的变化规律,但变幅较小;胡敏酸含碳量由23.5 g·kg-1逐渐增至51.4 g·kg-1,增幅为118.9％;而富里酸碳含量则由46.1 g·kg-1逐渐降至20.8 g·kg-1,降幅为54.8％.紫外光谱表明,堆腐过程中胡敏酸和富里酸的最大吸收峰位置没有发生明显变化,但峰形变宽,E465/E665值降低;傅立叶变换红外光谱表明,堆腐前后胡敏酸和富里酸特征吸收峰位置比较相近,但某些官能团的强度发生改变,堆腐后胡敏酸和富里酸的芳构化和腐殖化程度提高.%Sewage sludge originates as a by-product from the waste water treatment process.It includes lots of toxic and harmful substances such as heavy meatals,organic pollutants,pathogenic bacterias and parasitic ovums.In order to clarify the effects of composting on humic substances in sewage sludge,this study conducted composting experiment for 30 days under the initial condions of sewage sludge ∶ peat ∶ straw=3 ∶ 1 ∶ 2 (calculated by dry weight) and 55％ water content.The variation of the component and structure of humic substances in sewage sludge that occurred during composting was studied through the instruments of ultraviolet spectrograph and infrared spectrograph.The results indicated that,the concentrations of humic substances-carbon increased after an early decrease;the concentrations of humic acids-carbon ranged from 23.5 g·kg-1 to 51.4 g·kg-1 with a increasing rate of 118.9％,while the concentrations of fulvic acids-carbon ranged from 46.1 g·kg-1 to 20.8 g·kg-1 with a reduction rate of 54.8％.Ultraviolet spectroscopy detected no obvious change in the wavelength of the maximum absorption peak,but the peak shape was broadened,with decreased E465/E665 ratio.Fourier transform infrared spectroscopy revealed the similar peak pattems for humic acids and fulvic acids,but the intensities of some peaks became stronger at the end of the composting.The aromatization and humification of humic acids and fulvic acids increased during sewage sludge composting.
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