沼气发酵系统是一个复杂的生态系统,其污泥微生物超过99%是不可培养的。为了优化沼气池纤维素的转化效率、沼气的产率和开展污泥微生物多样性研究,本研究采用化学裂解法、溶菌酶裂解法和QIAampDNA Stool Mini Kit提取了沼气池污泥样品...沼气发酵系统是一个复杂的生态系统,其污泥微生物超过99%是不可培养的。为了优化沼气池纤维素的转化效率、沼气的产率和开展污泥微生物多样性研究,本研究采用化学裂解法、溶菌酶裂解法和QIAampDNA Stool Mini Kit提取了沼气池污泥样品中微生物的总DNA,对三种方法的DNA得率、纯度、大片段提取效果以及是否含有PCR反应抑制剂进行了研究,最后对16S rRNA基因V3区的扩增产物进行了PCR变性梯度凝胶电泳(PCR-DGGE)分析。与化学裂解法和QIAamp DNA Stool Mini Kit法相比,溶菌酶裂解法得到的DNA量大、片段长、片段分布广、PCR扩增效率高;同时PCR-DGGE图谱显示,溶菌酶裂解法可更好地展示沼气池污泥中微生物的多样性。该结果为进一步提高沼气池中纤维素的转化效率和沼气生产优势菌种的质和量打下了一定的前期基础。展开更多
The purpose of this work was to study the potential to enhance biogas production from pulp and paper mill sludge by the use of thermal pre-treatment in combination with chemical pre-treatment. Biogas from waste is a r...The purpose of this work was to study the potential to enhance biogas production from pulp and paper mill sludge by the use of thermal pre-treatment in combination with chemical pre-treatment. Biogas from waste is a renewable fuel with very low emissions during combustion. To further reduce the use of fossil fuels, more biogas substrates are necessary. Pulp and paper mill sludge is a large untapped reservoir of potential biogas. Pulp and paper mill sludge was collected from a mill that produces both pulp and paper and has a modified waste activated sludge system as part of its wastewater treatment. Pre-treatments were chosen heat (70 ~C or 140℃) combined with either acid (pH 2 or pH 4) or base (pH 9 or pH 11, obtained with Ca(OH)2 or NaOH). Biogas potential was tested by anaerobic digestion batch assays under mesophilic conditions. All pre-treatments were tested in six replicates. Biogas volume was measured with a gas-tight syringe and methane concentration was measured with a gas chromatograph. The methane yield from sludge subjected to thermal pre-treatment at 70℃ did not differ from the untreated sludge, but thermal pre-treatment at 140℃ had a positive effect. Within the 70℃ thermal pre-treatment group, the pH 2 acid was the most successful chemical pre-treatment, and Ca(OH)2 pH 9 had the least effect with no measurable improvement in methane yield. For the 140 ℃ thermal pre-treatment group, acid and NaOH impacted methane production negatively, while the Ca(OH)2-treated sludge did not differ from sludge with no chemical pre-treatment. In conclusion, thermal pre-treatment at 70℃ showed no effect, whereas, pre-treatment at 140℃ improved methane yield with 170%, and for this sludge additional, chemical pre-treatments are unnecessary.展开更多
This paper presents the results obtained for the effluent dewatering properties of anaerobic digestion of secondary sludge (SS) and anaerobic co-digestion of mixture of this sludge with the distillery wastewater (D...This paper presents the results obtained for the effluent dewatering properties of anaerobic digestion of secondary sludge (SS) and anaerobic co-digestion of mixture of this sludge with the distillery wastewater (DW) under thermophilic (55±1 ℃), 5 L of working volume, three parallel lab-scale conditions. Its mixtures were prepared with a DW content of 25%and 50% and the C/N ratios of mixtures are 13.1 and 17.6, respectively. The effluent dewatering properties were evaluated under stable conditions which the biogas yield and the effluent pH were steady. The natural settleability, biogas yield, centrifugal dewatering, centrifugal supernatant turbidity and specific resistance filtration (SRF) were investigated. The results showed that the effluent dewatering properties of anaerobic co-digestion of mixtures between SS and DW were better than that of anaerobic digestion of SS alone. In the anaerobic digestion system with the feed were SS, mixture of SS and a DW content of 25%and 50% in order, the net biogas yield of secondary sludge in ADSA,ADSB and ADSC were 0.42 0.507 and 0.511 m3 biogass/kg.VS.d ; compared with the biogas yield in anaerobic digestion system A (ADSA), the biogas yield in anaerobic digestion system B (ADSB) and anaerobic digestion system C (ADSC) had been increased by more than 20% respectively; the SRF of three digested sludge are(were) from 6.8×10^13, 1. 1×10^13 to 5.1×10^12 m/Kg, natural settling rates of 12 h are 26, 37 and 56% and that of 24 h are 32%, 45% and 59% respectively; the centrifugal dewatering rate of 3 min at speed of 1000 rpm were 16%, 31% and 51% respectively; the turbidity of centrifugal supernatant were 804, 754 and 678FTU simultaneously.展开更多
Processing cow manure into biogas is a solution to reduce air pollutant, because it reduces the smell of the manure up to 70%. Besides producing biogas, the sludge of biodigester can also serve as solid and liquid fer...Processing cow manure into biogas is a solution to reduce air pollutant, because it reduces the smell of the manure up to 70%. Besides producing biogas, the sludge of biodigester can also serve as solid and liquid fertilizer. The solid fertilizer can be used as carder of entomopathogenic fungi to control the pest which lives underground. The research aimed to investigate the benefits of biodigester sludge as fertilizer and carrier of entomopathogenic fungi (Cordyceps sp.) to control white grub pest. The use of organic fertilizer and pesticide in the cultivation can minimize the environmental hazard. The method used in the study was completely randomized design with four treatments, which were the addition of Cordyceps sp. corn media as much as 0, 10, 20 and 30 g/kg of sludge. Every addition was repeated three times to corn planted in a tub. To examine the effect of the treatments, the data were analyzed with ANOVA and Duncan test was applied when differences occurred between treatments. The results of the research showed that the nutrients contained in the manure which had been processed into biogas were not lost. The plants cultivated in the planting medium supplemented with sludge grew healthier, bigger, taller and had stronger and longer roots. On the contrary, the plants cultivated without sludge addition were vulnerable to white grub attack. The Cordyceps sp., which was added into the sludge, was effective to control the white grub. The concentration of Cordyceps sp. as much as 20 g/kg of sludge in corn planting medium was the most effective concentration to control white grub pest.展开更多
This paper presents bench scale experiments related to anaerobic co-digestion of aerobic sewage sludge from a pilot WWTP (waste water treatment plants), raw glycerol from a biodiesel industry and food waste. Assays ...This paper presents bench scale experiments related to anaerobic co-digestion of aerobic sewage sludge from a pilot WWTP (waste water treatment plants), raw glycerol from a biodiesel industry and food waste. Assays were conducted in 100 mL non-stirring penicillin vessels, at 30 ℃ and planned according to three optimization phases: (1) binary mixture of sewage sludge and FW (food waste); (2) binary mixture of sewage sludge and glycerol; and (3) ternary mixture of sewage sludge, FW, and glycerol. In the first and second phases, the highest SMP (specific methane production) was achieved by 10% (v/v) FW and 0.5% (v/v) glycerol mixtures. The optimization of the ternary mixture during the third phase was reached by the combination of 10% (v/v) FW and 0.4% (v/v) glycerol. Despite the low SMP value, the addition of glycerol and FW contributed to doubling the SMP value of the sludge sample control.展开更多
文摘沼气发酵系统是一个复杂的生态系统,其污泥微生物超过99%是不可培养的。为了优化沼气池纤维素的转化效率、沼气的产率和开展污泥微生物多样性研究,本研究采用化学裂解法、溶菌酶裂解法和QIAampDNA Stool Mini Kit提取了沼气池污泥样品中微生物的总DNA,对三种方法的DNA得率、纯度、大片段提取效果以及是否含有PCR反应抑制剂进行了研究,最后对16S rRNA基因V3区的扩增产物进行了PCR变性梯度凝胶电泳(PCR-DGGE)分析。与化学裂解法和QIAamp DNA Stool Mini Kit法相比,溶菌酶裂解法得到的DNA量大、片段长、片段分布广、PCR扩增效率高;同时PCR-DGGE图谱显示,溶菌酶裂解法可更好地展示沼气池污泥中微生物的多样性。该结果为进一步提高沼气池中纤维素的转化效率和沼气生产优势菌种的质和量打下了一定的前期基础。
文摘The purpose of this work was to study the potential to enhance biogas production from pulp and paper mill sludge by the use of thermal pre-treatment in combination with chemical pre-treatment. Biogas from waste is a renewable fuel with very low emissions during combustion. To further reduce the use of fossil fuels, more biogas substrates are necessary. Pulp and paper mill sludge is a large untapped reservoir of potential biogas. Pulp and paper mill sludge was collected from a mill that produces both pulp and paper and has a modified waste activated sludge system as part of its wastewater treatment. Pre-treatments were chosen heat (70 ~C or 140℃) combined with either acid (pH 2 or pH 4) or base (pH 9 or pH 11, obtained with Ca(OH)2 or NaOH). Biogas potential was tested by anaerobic digestion batch assays under mesophilic conditions. All pre-treatments were tested in six replicates. Biogas volume was measured with a gas-tight syringe and methane concentration was measured with a gas chromatograph. The methane yield from sludge subjected to thermal pre-treatment at 70℃ did not differ from the untreated sludge, but thermal pre-treatment at 140℃ had a positive effect. Within the 70℃ thermal pre-treatment group, the pH 2 acid was the most successful chemical pre-treatment, and Ca(OH)2 pH 9 had the least effect with no measurable improvement in methane yield. For the 140 ℃ thermal pre-treatment group, acid and NaOH impacted methane production negatively, while the Ca(OH)2-treated sludge did not differ from sludge with no chemical pre-treatment. In conclusion, thermal pre-treatment at 70℃ showed no effect, whereas, pre-treatment at 140℃ improved methane yield with 170%, and for this sludge additional, chemical pre-treatments are unnecessary.
文摘This paper presents the results obtained for the effluent dewatering properties of anaerobic digestion of secondary sludge (SS) and anaerobic co-digestion of mixture of this sludge with the distillery wastewater (DW) under thermophilic (55±1 ℃), 5 L of working volume, three parallel lab-scale conditions. Its mixtures were prepared with a DW content of 25%and 50% and the C/N ratios of mixtures are 13.1 and 17.6, respectively. The effluent dewatering properties were evaluated under stable conditions which the biogas yield and the effluent pH were steady. The natural settleability, biogas yield, centrifugal dewatering, centrifugal supernatant turbidity and specific resistance filtration (SRF) were investigated. The results showed that the effluent dewatering properties of anaerobic co-digestion of mixtures between SS and DW were better than that of anaerobic digestion of SS alone. In the anaerobic digestion system with the feed were SS, mixture of SS and a DW content of 25%and 50% in order, the net biogas yield of secondary sludge in ADSA,ADSB and ADSC were 0.42 0.507 and 0.511 m3 biogass/kg.VS.d ; compared with the biogas yield in anaerobic digestion system A (ADSA), the biogas yield in anaerobic digestion system B (ADSB) and anaerobic digestion system C (ADSC) had been increased by more than 20% respectively; the SRF of three digested sludge are(were) from 6.8×10^13, 1. 1×10^13 to 5.1×10^12 m/Kg, natural settling rates of 12 h are 26, 37 and 56% and that of 24 h are 32%, 45% and 59% respectively; the centrifugal dewatering rate of 3 min at speed of 1000 rpm were 16%, 31% and 51% respectively; the turbidity of centrifugal supernatant were 804, 754 and 678FTU simultaneously.
文摘Processing cow manure into biogas is a solution to reduce air pollutant, because it reduces the smell of the manure up to 70%. Besides producing biogas, the sludge of biodigester can also serve as solid and liquid fertilizer. The solid fertilizer can be used as carder of entomopathogenic fungi to control the pest which lives underground. The research aimed to investigate the benefits of biodigester sludge as fertilizer and carrier of entomopathogenic fungi (Cordyceps sp.) to control white grub pest. The use of organic fertilizer and pesticide in the cultivation can minimize the environmental hazard. The method used in the study was completely randomized design with four treatments, which were the addition of Cordyceps sp. corn media as much as 0, 10, 20 and 30 g/kg of sludge. Every addition was repeated three times to corn planted in a tub. To examine the effect of the treatments, the data were analyzed with ANOVA and Duncan test was applied when differences occurred between treatments. The results of the research showed that the nutrients contained in the manure which had been processed into biogas were not lost. The plants cultivated in the planting medium supplemented with sludge grew healthier, bigger, taller and had stronger and longer roots. On the contrary, the plants cultivated without sludge addition were vulnerable to white grub attack. The Cordyceps sp., which was added into the sludge, was effective to control the white grub. The concentration of Cordyceps sp. as much as 20 g/kg of sludge in corn planting medium was the most effective concentration to control white grub pest.
文摘This paper presents bench scale experiments related to anaerobic co-digestion of aerobic sewage sludge from a pilot WWTP (waste water treatment plants), raw glycerol from a biodiesel industry and food waste. Assays were conducted in 100 mL non-stirring penicillin vessels, at 30 ℃ and planned according to three optimization phases: (1) binary mixture of sewage sludge and FW (food waste); (2) binary mixture of sewage sludge and glycerol; and (3) ternary mixture of sewage sludge, FW, and glycerol. In the first and second phases, the highest SMP (specific methane production) was achieved by 10% (v/v) FW and 0.5% (v/v) glycerol mixtures. The optimization of the ternary mixture during the third phase was reached by the combination of 10% (v/v) FW and 0.4% (v/v) glycerol. Despite the low SMP value, the addition of glycerol and FW contributed to doubling the SMP value of the sludge sample control.