摘要
向污泥中加入NaOH进行微波热水解实验.结果表明,每1 g污泥悬浮固体(SS)添加NaOH 0.1 g时,污泥中的挥发性悬浮固体(VSS)快速水解,170℃的VSS溶解率达到60%以上,热水解后污泥的有机物含量(VSS/SS)降低至25%.80、120、150和170℃热水解5 min的污泥液相COD浓度分别为9.8、12.8、15.1和14.5 g/L,相应SCOD/TCOD为24.0%、31.3%、36.9%和35.6%.随温度的升高和时间的延长热水解污泥pH越低,最低值〉10.5.在每1 g SS添加0-0.2g NaOH的范围内,当添加量〉0.05 g时,VSS和SS的溶解率增加幅度降低.分别对NaOH添加量0.05 g热水解5 min和添加量0.1 g热水解1 min的污泥进行BMP厌氧消化实验.结果表明,添加量为0.05 g时热水解污泥的厌氧消化性能提高,经150℃处理污泥的产气量最大,比未处理污泥高28.5%,而在添加量为0.1 g时,污泥的厌氧消化性能受到抑制,产气量低于未处理污泥.
NaOH was added into sludge to improve thermal hydrolysis when heated with microwave irradiation. Volatile suspended solid (VSS) rapidly dissolved into aqueous phase when adding 0.1 g NaOH per gram into suspended solid (SS) of sludge. More than 60% of VSS solubilized at 170℃ , and VSS to SS ratio of treated sludge reduced to 25% . For 5min treatment, soluble COD (SCOD) in treated sludge liquid phase was 9.8, 12.8, 15.1, and 14.5g/L respectively at 80,120,150 and 170℃ . Accordingly, the SCOD to TCOD (total COD) ratio was 24.0% , 31.3 % , 36.9 % and 35.6 % . The pH of the microwave heated sludge decreased with higher temperature and longer hydrolysis time, while the finale pH of different testes were still higher than 10.5. Alkali dose effect on organic matters dissolving was analyzed at the range of 0-0.2 g NaOH into per gram SS. Results showed that when alkali dose was above 0.05 g, the rapid dissolving trend became level for VSS and SS. BMP (biochemical methane potential) test was used to investigate treated sludge digestibility at NaOH dose of 0.05g with 5min microwave heating at set temperature and 0. 1 g with lmin heating. Results showed that adding 0.05 g NaOH improved sludge anaerobic digestion, the biogas production was 28.5 % higher than control at 150℃, while adding 0.1 g NaOH would inhibit treated sludge digestion process.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2009年第9期2678-2683,共6页
Environmental Science
基金
国家高技术研究发展计划(863)项目(2006AA06Z384)
关键词
污泥
碱
微波
热水解
sludge
alkali
microwave
thermal hydrolysis