污泥与生物质共热解制备生物质炭工艺优化及吸附性能
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摘要
通过污泥与秸秆(玉米秸秆、水稻秸秆、小麦秸秆、芝麻秸秆)慢速共热解的方法,在不同热解温度(300℃、400℃、500℃、600℃)、热解时间(0.5h、1h、1.5h、2h)及配比(污泥与生物质1∶0、1∶0.5、1∶1、1∶2)条件下制备4种生物质炭,即SCBC(污泥-玉米秸秆生物质炭)、SRBC(污泥-水稻秸秆生物质炭)、SWBC(污泥-小麦生物质炭)、SSBC(污泥-芝麻生物质炭),研究了不同热解条件对生物质炭产率、pH、元素组成、表面特征、吸附性能的影响,并根据吸附性能筛选出各生物质炭的最优制备工艺。结果表明,热解温度为500℃、热解时间为2h、污泥与玉米秸秆、芝麻秸秆配比为1∶1时,污泥与水稻秸秆、小麦秸秆配比为1∶2时,制备的生物质炭吸附性能最优。最优制备工艺条件下,4种生物质炭吸附性能相比:SWBC>SRBC>SCBC>SSBC。
Biochars were produced by slow co-pyrolysis of sewage sludge and straws(corn straw, rice straw, wheat straw, sesame straw) at different pyrolysis temperatures(300℃, 400℃, 500℃, 600℃), pyrolysis times(0.5 h, 1 h, 1.5 h, 2 h) and ratios(sludge/biomass 1∶0, 1∶0.5, 1∶1, 1∶2). The four types of biochars were labelled SCBC(biochar derived from sludge and corn straw), SRBC(biochar derived from sludge and rice straw), SWBC(biochar derived from sludge and wheat straw), SSBC(biochar derived from sludge and sesame biomass), respectively. The effect of different pyrolysis temperatures, times, and ratios on pH, yields, ash contents, pore characteristics, and adsorption capacity was studied. Based on the adsorption properties, the optimum production process of biochar was determined. The results showed that when the pyrolysis temperature was 500℃, the pyrolysis time was 2 h, the ratio of sludge to corn straw and sesame straw was 1∶1, the ratio of sludge to rice straw and wheat straw was 1∶2, the adsorption performance of biochar was the best. Under the optimum preparation conditions, the adsorption properties of four kinds of biochars followed the order: SWBC>SRBC>SCBC>SSBC. This study provides technical support for the utilization of sewage sludge and straws.
Biochars were produced by slow co-pyrolysis of sewage sludge and straws(corn straw, rice straw, wheat straw, sesame straw) at different pyrolysis temperatures(300℃, 400℃, 500℃, 600℃), pyrolysis times(0.5 h, 1 h, 1.5 h, 2 h) and ratios(sludge/biomass 1∶0, 1∶0.5, 1∶1, 1∶2). The four types of biochars were labelled SCBC(biochar derived from sludge and corn straw), SRBC(biochar derived from sludge and rice straw), SWBC(biochar derived from sludge and wheat straw), SSBC(biochar derived from sludge and sesame biomass), respectively. The effect of different pyrolysis temperatures, times, and ratios on pH, yields, ash contents, pore characteristics, and adsorption capacity was studied. Based on the adsorption properties, the optimum production process of biochar was determined. The results showed that when the pyrolysis temperature was 500℃, the pyrolysis time was 2 h, the ratio of sludge to corn straw and sesame straw was 1∶1, the ratio of sludge to rice straw and wheat straw was 1∶2, the adsorption performance of biochar was the best. Under the optimum preparation conditions, the adsorption properties of four kinds of biochars followed the order: SWBC>SRBC>SCBC>SSBC. This study provides technical support for the utilization of sewage sludge and straws.
引文
[1]桂成民,李萍,王亚炜,等.剩余污泥微波热解技术研究进展[J].化工进展,2015,34(9):3435-3443,3475.
[2]李懂学.中小型污水厂剩余污泥合成燃料的实验研究[D].重庆:重庆大学,2008.
[3]邓辉,李政家,金志文,等.棉秆与污泥共热解制备生物炭工艺优化及其结构与吸附性能[J].农业工程学报,2016,32(24):248-254.
[4]卢再亮,李九玉,姜军,等.生活污水污泥制备的生物质炭对红壤酸度的改良效果及其环境风险[J].环境科学,2012,33(10):3585-3591.
[5]施川.污泥生物炭作为吸附剂和酸性土壤改良剂的可行性研究[D].北京:北京林业大学,2016.
[6]郑凯琪.污泥生物炭对环境中Pb、Cd固持的研究[D].扬州:扬州大学,2016.
[7]JIN Junwei,WANG Minyan,CAO Yucheng,et al.Cumulative effects of bamboo sawdust addition on pyrolysis of sewage sludge:biochar properties and environmental risk from metals[J].Bioresource Technology,2017,228:218-226.
[8]张阿凤,潘根兴,李恋卿.生物黑炭及其增汇减排与改良土壤意义[J].农业环境科学学报,2009,28(12):2459-2463.
[9]CORNELISSEN G,GUSTAFSSON O,BUCHELI T D,et al.Extensive sorption of organic compounds to black carbon,coal,and kerogen in sediments and soils:mechanisms and consequences for distribution bioaccumulation,and biodegradation[J].Environmental Science&Technology,2005,39(18):6881-6895.
[10]张栋,刘兴元,赵红挺.生物质炭对土壤无机污染物迁移行为影响研究进展[J].浙江大学学报(农业与生命科学版),2016,42(4):451-459.
[11]彭文龙.生物质炭表面物质对微生物的影响研究[D].重庆:重庆大学,2014.
[12]俞花美,陈淼,邓惠,等.蔗渣基生物质炭的制备、表征及吸附性能[J].热带作物学报,2014,35(3):595-602.
[13]汤斯奇,王经臣,JAEHAC Ko.不同热解终温和保留时间下污泥生物质炭孔隙结构特征[J].北京大学学报(自然科学版),2017,53(5):890-898.
[2]李懂学.中小型污水厂剩余污泥合成燃料的实验研究[D].重庆:重庆大学,2008.
[3]邓辉,李政家,金志文,等.棉秆与污泥共热解制备生物炭工艺优化及其结构与吸附性能[J].农业工程学报,2016,32(24):248-254.
[4]卢再亮,李九玉,姜军,等.生活污水污泥制备的生物质炭对红壤酸度的改良效果及其环境风险[J].环境科学,2012,33(10):3585-3591.
[5]施川.污泥生物炭作为吸附剂和酸性土壤改良剂的可行性研究[D].北京:北京林业大学,2016.
[6]郑凯琪.污泥生物炭对环境中Pb、Cd固持的研究[D].扬州:扬州大学,2016.
[7]JIN Junwei,WANG Minyan,CAO Yucheng,et al.Cumulative effects of bamboo sawdust addition on pyrolysis of sewage sludge:biochar properties and environmental risk from metals[J].Bioresource Technology,2017,228:218-226.
[8]张阿凤,潘根兴,李恋卿.生物黑炭及其增汇减排与改良土壤意义[J].农业环境科学学报,2009,28(12):2459-2463.
[9]CORNELISSEN G,GUSTAFSSON O,BUCHELI T D,et al.Extensive sorption of organic compounds to black carbon,coal,and kerogen in sediments and soils:mechanisms and consequences for distribution bioaccumulation,and biodegradation[J].Environmental Science&Technology,2005,39(18):6881-6895.
[10]张栋,刘兴元,赵红挺.生物质炭对土壤无机污染物迁移行为影响研究进展[J].浙江大学学报(农业与生命科学版),2016,42(4):451-459.
[11]彭文龙.生物质炭表面物质对微生物的影响研究[D].重庆:重庆大学,2014.
[12]俞花美,陈淼,邓惠,等.蔗渣基生物质炭的制备、表征及吸附性能[J].热带作物学报,2014,35(3):595-602.
[13]汤斯奇,王经臣,JAEHAC Ko.不同热解终温和保留时间下污泥生物质炭孔隙结构特征[J].北京大学学报(自然科学版),2017,53(5):890-898.