[Objective] This study aimed to provide reliable theoretical basis for re- source utilization of sludge. [Method] By using pot experiment, variations of the yield index and salt content of rape and the accumulation of...[Objective] This study aimed to provide reliable theoretical basis for re- source utilization of sludge. [Method] By using pot experiment, variations of the yield index and salt content of rape and the accumulation of three kinds of heavy metals in rape plants and soil including Hg, As and Zn were explored. [Result] The results showed that medium sludge level （50 g/pot） significantly increased the rape yield and root/shoot ratio; when the application amount of sludge reached 100 g/pot, the fertil- ization effect of sludge on potted rape yield was significantly reduced. Compared with chemical fertilizer and chicken manure, sludge promoted N and P absorption of rape more significantly, but the effect of sludge application on K absorption was less significant than chicken manure. Sludge can increase the soil salinity, which is higher than the chemical fertilizer and chicken manure, but the effect was not significant. Compared with chemical fertilizer and chicken manure treatments, the Hg, As and Zn contents in rape plants and soil after sludge application increased, to be specific, Hg content increased relatively significantly. Hg, As and Zn contents in rape plants and soil were all in accordance with China National Safety Standards for Heavy Met- als in Vegetables and China National Environmental Quality Standards for Soils. [Conclusion] Short-term sludge application will not lead to secondary heavy metal pollution of agricultural soils, but the Hg content should be monitored and controlled in long-term sludge application.展开更多
Based on the analysis of the properties of oily sludge samples,the effect of modification parameters,such as liquid to solid (L/S) ratio,agitation temperature,agitation intensity,agitation time and pH on the modificat...Based on the analysis of the properties of oily sludge samples,the effect of modification parameters,such as liquid to solid (L/S) ratio,agitation temperature,agitation intensity,agitation time and pH on the modification of oily sludge was investigated with the content of oil remnants in dry sludge as a reference index. Remixing experiments were carried out according to a simplex-lattice design,where Sx4056 was used as the demulsifier,petroleum sulfonate as the surfactant and sodium silicate (Na2SiO3) as the dispersant. The surface modification reagent formulation was optimized by a regression equation on the modified effect and based on the amounts of surface modification reagents. The results show that the content of the oil remaining in dry oily sludge is 0.28% of 10.15% oily sludge,when the reagent concentration rises to 3.5 g/L under the optimum experimental conditions.展开更多
Oil fields present a potential ecological risk to nearby farmland soil. Here we present a new method designed to evaluate the ability of winter wheat(Triticum aestivum) to contribute to the dissipation of polycyclic a...Oil fields present a potential ecological risk to nearby farmland soil. Here we present a new method designed to evaluate the ability of winter wheat(Triticum aestivum) to contribute to the dissipation of polycyclic aromatic hydrocarbons(PAHs), which are priority pollutants in soils contaminated by oily sludge. The influence of different doses of oily sludge on the dissipation of PAHs was studied along with individual PAH profiles in soils after different periods of plant growth. Five soil samples were artificially contaminated with different percentages of oily sludge(0 %, 5 %, 10 %, 15 % and 20 %). Winter wheat grew in the oily sludge–amended soils for 265 days.PAH content in the soils was monitored over the course of the study. The rate of PAH dissipation is related to the properties of different PAHs, period of winter wheat growth, and oily sludge application dose. Analysis for treated soils indicates that the dissipation of PAHs increased significantly over the first 212 days, followed by minimal changes over the final 53 days of treatment. In contrast, PAH dissipation slowed with increasing oily sludge application. For each PAH, the experimental results showed a significant compound-dependent trend. Winter wheat in the present study significantly enhanced the dissipation of PAHs in oily sludge–contaminated soil.展开更多
The aim of this research was to know the impact of planting leguminous cover crops （LCCs） of Mucuna bracteata and Calopogonium mucunoides in oil palm plantation on peatland on reducing CO2 emissions. Atmosphere temp...The aim of this research was to know the impact of planting leguminous cover crops （LCCs） of Mucuna bracteata and Calopogonium mucunoides in oil palm plantation on peatland on reducing CO2 emissions. Atmosphere temperature, peat surface temperature, in-closed chamber temperature and peat surface CO2 fluxes were monitored on two adjacent experimental plots. The first experimental plot was on the newly opened peat surface （NOPS） and another was on the eight years planted oil palm land （EPOL）. The closed chamber techniques adopted from International Atomic Energy Agency （IAEA） （1993） were implemented to trap CO2 emissions emitted from 24 treatment plots at the 1st, 3rd and 6th months observations. Average CO2 fluxes observed on no LCCs plots in the NOPS site were 61.25 ± 8.98, 33.76 ± 2.92 and 33.75 ± 3.45 g/m2.h, while in the EPOL site were 55.38 ± 15.95, 29.90 ± 5.32 and 27.70 ± 4.62 g/mLh at the 1st, 3rd and 6th months monitoring, respectively. Average CO2 fluxes observed on the planted M. bracteata plots in the NOPS site were 68.2 ± 24.5, 12.88 ± 3.70 and 10.40 ± 1.28 g/m2.h, whereas in the EPOL site were 54.04 ± 6.70, 11.45 ± 2.00 and 9.33 ± 3.49 g/m2.h at the 1st, 3rd and 6th months monitoring, respectively. Average CO2 flux observed on the planted C. mucunoides plots in the NOPS site were 66.5 ± 23.7, 15.41 ± 1.51 and 9.74 ± 2.55 g/m2.h, while in the EPOL site were 47.00 ± 5.00, 9.34 ± 1.23 and 10.52 ± 4.80 g/m2.h at the 1st, 3rd and 6th months, respectively. P-value for the experimental sites was 0.008 （〈 0.05）, indicating the significant difference in the level of CO2 fluxes between the sites. P-value for the treatments in the experimental plots was 0.000 （〈 0.05）, indicating markedly different level of CO2 fluxes among treatments. P-value for the age ofM. bracteata and C. mucunoides planted on the experimental plots was 0.000 （〈 0.05）, indicating the significant difference in the level of CO2 fluxes due to the enhanced LCCs age performing at the increase of shading effects. The comparison of CO2 fluxes among experimental plots shows that planting M. bracteata and C. mucunoides on the peatland could reduce CO2 emission.展开更多
The hydrolysate of waste sludge was used as the feedstock of biodiesel production,and its technological feasibility was investigated.Waste sludge,collected from No.3 Municipal Wastewater Treatment Plant of Xi’an,was ...The hydrolysate of waste sludge was used as the feedstock of biodiesel production,and its technological feasibility was investigated.Waste sludge,collected from No.3 Municipal Wastewater Treatment Plant of Xi’an,was hydrolyzed in two parallel reactors firstly.Yeast was added into one reactor for bioaugmentation,and the other reactor without yeast was used as a control.Then an acid-catalyzed in situ esterification process was carried out to convert the hydrolysate to biodiesel.The results of hydrolysis showed that the reactor bioaugmented with yeast could promote hydrolysis compared with the control one because of an obvious variance in total suspended solid(TSS),volatile suspended solid(VSS)and soluble chemical oxygen demand(SCOD).Furthermore,gas chromatography(GC)analysis exhibited that the total volatile fatty acid(VFA)was low in the hydrolysate of bioaugmentation reactor;however,its yield of the fatty acid methyl esters(FAMEs)by in situ esterification was obviously higher when compared with the control one.Therefore,it may be inferred that the hydrolysate of bioaugmentation was mainly inclined to longer-chain fatty acid rather than to VFA.Anyway,an FAMEs yield of 9.24%(wt%)from dried sludge was attained after the 12-d bioaugmentation hydrolysis and succedent esterification.This value was not only higher than that of the control one but also higher than that reported in previous literature.The above results illuminated that it was feasible to produce biodiesel from the bioaugmented hydrolysate of waste sludge.展开更多
Sludge palm oil （SPO） is an attractive feedstock and a significant raw material for biodiesel production. The use of SPO can lower the cost ofbiodiesel production significantly. In this study biodiesel fuel was prod...Sludge palm oil （SPO） is an attractive feedstock and a significant raw material for biodiesel production. The use of SPO can lower the cost ofbiodiesel production significantly. In this study biodiesel fuel was produced from SPO by esterification process using P-toluenesulfonic acid （PTSA） as acid catalyst in different dosages in presence of methanol to convert free fatty acid （FFA） to fatty acid methyl ester （FAME）. Batch esterification process of SPO was carried out to study the influence of PTSA dosage （0.25-10% wt/wt）, molar ratio of methanol to SPO （6：1-20：1）, temperature （40-80 ℃）, reaction time （30-120 min）. The effects of those parameters on the yield of crude biodiesel and conversion of FFA to FAME were monitored. The optimum condition for batch esterification process was 0.75% wt/wt, 10：1 molar ratio, 60 ℃ temperature and 60 minutes reaction time.展开更多
The interaction of Si anions with Al sites during the hydration process was observed by NMR, IR and SEM to understand the reaction mechanism of the hydrates formation mixed with oil shale calcined at different tempera...The interaction of Si anions with Al sites during the hydration process was observed by NMR, IR and SEM to understand the reaction mechanism of the hydrates formation mixed with oil shale calcined at different temperatures. As the reaction progressed, the coordination of Al （Ⅳ, Ⅴ, and Ⅵ） changed almost completely to Ⅳ, when mixed with oil shale calcined at 700 ℃. However, when mixed with oil shale calcined at 400 ℃, some 6-coordination of Al still remained in the hydrates. Under the function of alkaline solutions, which were produced with the hydration of clinker, a certain amount of Si and Al atoms dissolved or hydrolyzed from aluminosilicate, formed geomonomers in solutions, and then polycondensed to form networks.展开更多
基金Supported by Scientific and Technological Support Project for Quality and Safety Testing and Monitoring of Bulk Agricultural Products Produced in Beijing(Z090905-01040901)Cooperation Project of Beijing Drainage Group Co.Ltd."Study on Agronomic and Environmental Effects of Long-term Application of Sludge"~~
文摘[Objective] This study aimed to provide reliable theoretical basis for re- source utilization of sludge. [Method] By using pot experiment, variations of the yield index and salt content of rape and the accumulation of three kinds of heavy metals in rape plants and soil including Hg, As and Zn were explored. [Result] The results showed that medium sludge level （50 g/pot） significantly increased the rape yield and root/shoot ratio; when the application amount of sludge reached 100 g/pot, the fertil- ization effect of sludge on potted rape yield was significantly reduced. Compared with chemical fertilizer and chicken manure, sludge promoted N and P absorption of rape more significantly, but the effect of sludge application on K absorption was less significant than chicken manure. Sludge can increase the soil salinity, which is higher than the chemical fertilizer and chicken manure, but the effect was not significant. Compared with chemical fertilizer and chicken manure treatments, the Hg, As and Zn contents in rape plants and soil after sludge application increased, to be specific, Hg content increased relatively significantly. Hg, As and Zn contents in rape plants and soil were all in accordance with China National Safety Standards for Heavy Met- als in Vegetables and China National Environmental Quality Standards for Soils. [Conclusion] Short-term sludge application will not lead to secondary heavy metal pollution of agricultural soils, but the Hg content should be monitored and controlled in long-term sludge application.
基金Project(50974119) supported by the National Natural Science Foundation of ChinaProject(2006A019) supported by the Science and Technology Fund of China University of Mining and Technology
文摘Based on the analysis of the properties of oily sludge samples,the effect of modification parameters,such as liquid to solid (L/S) ratio,agitation temperature,agitation intensity,agitation time and pH on the modification of oily sludge was investigated with the content of oil remnants in dry sludge as a reference index. Remixing experiments were carried out according to a simplex-lattice design,where Sx4056 was used as the demulsifier,petroleum sulfonate as the surfactant and sodium silicate (Na2SiO3) as the dispersant. The surface modification reagent formulation was optimized by a regression equation on the modified effect and based on the amounts of surface modification reagents. The results show that the content of the oil remaining in dry oily sludge is 0.28% of 10.15% oily sludge,when the reagent concentration rises to 3.5 g/L under the optimum experimental conditions.
基金jointly supported by National Natural Science Foundation of China(41541025)Open Research Fund Program of Shandong Provincial Key Laboratory of Eco-Environmental Science for Yellow River Delta(Binzhou University)(2015KFJJ01)
文摘Oil fields present a potential ecological risk to nearby farmland soil. Here we present a new method designed to evaluate the ability of winter wheat(Triticum aestivum) to contribute to the dissipation of polycyclic aromatic hydrocarbons(PAHs), which are priority pollutants in soils contaminated by oily sludge. The influence of different doses of oily sludge on the dissipation of PAHs was studied along with individual PAH profiles in soils after different periods of plant growth. Five soil samples were artificially contaminated with different percentages of oily sludge(0 %, 5 %, 10 %, 15 % and 20 %). Winter wheat grew in the oily sludge–amended soils for 265 days.PAH content in the soils was monitored over the course of the study. The rate of PAH dissipation is related to the properties of different PAHs, period of winter wheat growth, and oily sludge application dose. Analysis for treated soils indicates that the dissipation of PAHs increased significantly over the first 212 days, followed by minimal changes over the final 53 days of treatment. In contrast, PAH dissipation slowed with increasing oily sludge application. For each PAH, the experimental results showed a significant compound-dependent trend. Winter wheat in the present study significantly enhanced the dissipation of PAHs in oily sludge–contaminated soil.
文摘The aim of this research was to know the impact of planting leguminous cover crops （LCCs） of Mucuna bracteata and Calopogonium mucunoides in oil palm plantation on peatland on reducing CO2 emissions. Atmosphere temperature, peat surface temperature, in-closed chamber temperature and peat surface CO2 fluxes were monitored on two adjacent experimental plots. The first experimental plot was on the newly opened peat surface （NOPS） and another was on the eight years planted oil palm land （EPOL）. The closed chamber techniques adopted from International Atomic Energy Agency （IAEA） （1993） were implemented to trap CO2 emissions emitted from 24 treatment plots at the 1st, 3rd and 6th months observations. Average CO2 fluxes observed on no LCCs plots in the NOPS site were 61.25 ± 8.98, 33.76 ± 2.92 and 33.75 ± 3.45 g/m2.h, while in the EPOL site were 55.38 ± 15.95, 29.90 ± 5.32 and 27.70 ± 4.62 g/mLh at the 1st, 3rd and 6th months monitoring, respectively. Average CO2 fluxes observed on the planted M. bracteata plots in the NOPS site were 68.2 ± 24.5, 12.88 ± 3.70 and 10.40 ± 1.28 g/m2.h, whereas in the EPOL site were 54.04 ± 6.70, 11.45 ± 2.00 and 9.33 ± 3.49 g/m2.h at the 1st, 3rd and 6th months monitoring, respectively. Average CO2 flux observed on the planted C. mucunoides plots in the NOPS site were 66.5 ± 23.7, 15.41 ± 1.51 and 9.74 ± 2.55 g/m2.h, while in the EPOL site were 47.00 ± 5.00, 9.34 ± 1.23 and 10.52 ± 4.80 g/m2.h at the 1st, 3rd and 6th months, respectively. P-value for the experimental sites was 0.008 （〈 0.05）, indicating the significant difference in the level of CO2 fluxes between the sites. P-value for the treatments in the experimental plots was 0.000 （〈 0.05）, indicating markedly different level of CO2 fluxes among treatments. P-value for the age ofM. bracteata and C. mucunoides planted on the experimental plots was 0.000 （〈 0.05）, indicating the significant difference in the level of CO2 fluxes due to the enhanced LCCs age performing at the increase of shading effects. The comparison of CO2 fluxes among experimental plots shows that planting M. bracteata and C. mucunoides on the peatland could reduce CO2 emission.
基金Supported by Excellent Project from Shaanxi Administration of Foreign Expert Affairs in 2011International Cooperation Project of Shaanxi Province(No.2011KW-34)
文摘The hydrolysate of waste sludge was used as the feedstock of biodiesel production,and its technological feasibility was investigated.Waste sludge,collected from No.3 Municipal Wastewater Treatment Plant of Xi’an,was hydrolyzed in two parallel reactors firstly.Yeast was added into one reactor for bioaugmentation,and the other reactor without yeast was used as a control.Then an acid-catalyzed in situ esterification process was carried out to convert the hydrolysate to biodiesel.The results of hydrolysis showed that the reactor bioaugmented with yeast could promote hydrolysis compared with the control one because of an obvious variance in total suspended solid(TSS),volatile suspended solid(VSS)and soluble chemical oxygen demand(SCOD).Furthermore,gas chromatography(GC)analysis exhibited that the total volatile fatty acid(VFA)was low in the hydrolysate of bioaugmentation reactor;however,its yield of the fatty acid methyl esters(FAMEs)by in situ esterification was obviously higher when compared with the control one.Therefore,it may be inferred that the hydrolysate of bioaugmentation was mainly inclined to longer-chain fatty acid rather than to VFA.Anyway,an FAMEs yield of 9.24%(wt%)from dried sludge was attained after the 12-d bioaugmentation hydrolysis and succedent esterification.This value was not only higher than that of the control one but also higher than that reported in previous literature.The above results illuminated that it was feasible to produce biodiesel from the bioaugmented hydrolysate of waste sludge.
文摘Sludge palm oil （SPO） is an attractive feedstock and a significant raw material for biodiesel production. The use of SPO can lower the cost ofbiodiesel production significantly. In this study biodiesel fuel was produced from SPO by esterification process using P-toluenesulfonic acid （PTSA） as acid catalyst in different dosages in presence of methanol to convert free fatty acid （FFA） to fatty acid methyl ester （FAME）. Batch esterification process of SPO was carried out to study the influence of PTSA dosage （0.25-10% wt/wt）, molar ratio of methanol to SPO （6：1-20：1）, temperature （40-80 ℃）, reaction time （30-120 min）. The effects of those parameters on the yield of crude biodiesel and conversion of FFA to FAME were monitored. The optimum condition for batch esterification process was 0.75% wt/wt, 10：1 molar ratio, 60 ℃ temperature and 60 minutes reaction time.
基金Supported by the National Science and Technology (2006BAE03A11)the National Natural Science Foundation of China(50674062)
文摘The interaction of Si anions with Al sites during the hydration process was observed by NMR, IR and SEM to understand the reaction mechanism of the hydrates formation mixed with oil shale calcined at different temperatures. As the reaction progressed, the coordination of Al （Ⅳ, Ⅴ, and Ⅵ） changed almost completely to Ⅳ, when mixed with oil shale calcined at 700 ℃. However, when mixed with oil shale calcined at 400 ℃, some 6-coordination of Al still remained in the hydrates. Under the function of alkaline solutions, which were produced with the hydration of clinker, a certain amount of Si and Al atoms dissolved or hydrolyzed from aluminosilicate, formed geomonomers in solutions, and then polycondensed to form networks.
