养猪场沼渣提取高附加值产品——腐植酸的工艺研究

The Technique of Extracting Humic Acid from Pig Manure Biogas Fermentation Residue

针对养猪场沼渣产生量大,直接作为肥料,污染严重这一难题,文章以养猪场湿沼渣为原料,以盐酸、氢氧化钠、硫酸为助剂从中提取高附加值产品——腐植酸,优化了盐酸用量、活化温度、活化时间及氢氧化钠用量等影响沼渣提取腐植酸的因子。对于含水率94.19%,质量50 g的沼渣,当盐酸用量为50 m L,盐酸活化时间为45 min,活化温度为80℃、氢氧化钠用量为22 mmol时,可得纯腐植酸产品290 mg。红外光谱、核磁氢谱显示提取的腐植酸存在羟基、芳香烯烃等基团,扫描电镜(SEM)显示其形貌、结构未见明显差异,有利于该工艺工业化应用。从养猪场沼渣中提取腐植酸不仅原料易得、工艺操作比较简单,而且提取的腐植酸能够进一步提纯作为医用,产品附加值高,对于养猪场沼渣资源化利用意义重大。

The amount of biogas residue in the pig farm is large,and direct using as fertilizer will cause pollution problems. In this paper,the humic acid,a high valued product,was extracted from the pig farm biogas fermentation residue adopting hydrochloric acid,sodium hydroxide and sulfuric acid as accessory ingredient. The influence factors as dosage of hydrochloric acid,activation temperature and time,and concentration of sodium hydroxide,were optimized. Under dosage of hydrochloric acid 50 m L,activation time of 45 min,activation temperature of 80℃,and the sodium hydroxide concentration of 22 mmol,290 mg of pure humic acid product were obtained from 50 g of biogas residue with 94. 19% of moisture content. The spectra of IR and HNMR showed the presence of hydroxyl,aromatic olefin in the extracted humic acid. Scanning of electron microscopy（ SEM） showed that its morphology and structures did not have obvious difference.