돈분과 배추사일리지 혼합물을 이용한 바이오가스 생산

( Kafle,G. K ),박종태 ( J. T. Park ),김상헌 ( S. H. Kim ),성경일 ( K. I. Sung ) 강원대학교 농업생명과학연구원(구 농업과학연구소) 2011 강원 농업생명환경연구 Vol.23 No.4

The anaerobic co-digestion of Chinese cabbage waste silage (CCWS) and swine manure (SM) was carried out at mesophilic temperature (36-38oC) under batch mode. The mixtures ratios of SM and CCWS were 100:0, 75:25, 67:33, 33:67 and 0:100 (SM:CCWS) on a volatile solid (VS) basis at OLR of 16 gVS/L and F/M ratio of 1.6. After 40 days of digestion, biogas yield was calculated to be 425, 408, 410, 342 and 196 mL/gVS added for the SM:CCWS (100:0), SM:CCWS (75:25), SM:CCWS (67:33), SM:CCWS (33:67) and SM:CCWS (0:100), respectively. The result also showed that CCWS content in the feed can be used up to 67% (VS basis) without decreasing the methane yield per unit feedstock input (mL/g substrate added).

Isoxazolone Derivatives as Potent Inhibitors of PTP1B

Kafle, Bhooshan,Cho, Hyeong-Jin Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.1

Effects of Delignification on Crystalline Cellulose in Lignocellulose Biomass Characterized by Vibrational Sum Frequency Generation Spectroscopy and X-ray Diffraction

Kafle, K.,Lee, C. M.,Shin, H.,Zoppe, J.,Johnson, D. K.,Kim, S. H.,Park, S. SPRINGER SCIENCE + BUSINESS MEDIA 2015 Bioenergy research Vol.8 No.4

Barbituric Acid Derivatives as Protein Tyrosine Phosphatase Inhibitors

Kafle, Bhooshan,Bhattarai, Bharat Raj,Cho, Hyeong-Jin Korean Chemical Society 2011 Bulletin of the Korean Chemical Society Vol.32 No.1

Anaerobic Digestion Treatment for the Mixture of Chinese Cabbage Waste Juice and Swine Manure

Kafle, Gopi Krishna,Kim, Sang-Hun,Shin, Beom-Soo Korean Society for Agricultural Machinery 2012 바이오시스템공학 Vol.37 No.1

Purpose: The objective of this study was to investigate the feasibility of anaerobic digestion of Chinese cabbage waste juice (CCWJ) and swine manure(SM). Methods: The anaerobic digestion test was conducted under batch and continuous conditions at mesophilic temperature ($36-38^{\circ}C$). The batch test was divided into Experiment I and II. In the Experiment I, biogas potential and production rate of CCWJ was evaluated. In Experiment II the effect of F/M ratio (2.0, 3.2, 4.9) at mixture ratio of 25:75(CCWJ: SM, % vol. basis) on biogas yield was studied. Results: CCWJ produced biogas and methane yield of 929 and 700 mL/g VS added respectively. The biogas yield from the mixture of CCWJ and SM was almost same at F/M ratio of 2.0 and 3.2 but dropped by 14% when F/M ratio increased from 3.2 to 4.9. In continuous test the mixture of CCWJ and SM (25:75, % vol. basis) produced biogas yield of 352 mL/g VS added which is around 11% higher compared to biogas yield from SM alone. Addition to biogas yield digester performance was also improved with co-digestion of CCWJ with SM. Conclusions: The results showed that the anaerobic digestion of CCWJ with SM could be promising for improving both the biogas yield and digester performance at mesophilic temperature.

Kinetic Study of the Anaerobic Digestion of Swine Manure at Mesophilic Temperature: A Lab Scale Batch Operation

Kafle, Gopi Krishna,Kim, Sang-Hun Korean Society for Agricultural Machinery 2012 바이오시스템공학 Vol.37 No.4

Purpose: The kinetic evaluation was performed for swine manure (SM) degradation and biogas generation. Methods: The SM was anaerobically digested using batch digesters at feed to inoculum ratio (F/I) of 1.0 under mesophilic conditions ($36.5^{\circ}C$). The specific gas yield was expressed in terms of gram total chemical oxygen demand (mL/g TCOD added) and gram volatile solids added (mL/g VS added) and their effectiveness was discussed. The biogas and methane production were predicted using first order kinetic model and the modified Gompertz model. The critical hydraulic retention time for biomass washout was determined using Chen and Hashimoto model. Results: The biogas and methane yield from SM was 346 and 274 mL/ TCOD added, respectively after 100 days of digestion. The average methane content in the biogas produced from SM was 79% and $H_2S$ concentration was in the range of 3000-4108 ppm. It took around 32-47 days for 80-90% of biogas recovery and the TCOD removal from SM was calculated to be 85%. When the specific biogas and methane yield from SM (with very high TVFA concentration) was expressed in terms of oven dried volatile solids (VS) basis, the gas yield was found to be over estimated. The difference in the measured and predicted gas yield was in the range of 1.2-1.5% when using first order kinetic model and 0.1% when using modified Gompertz model. The effective time for biogas production ($T_{Ef}$) from SM was calculated to be in the range of 30-45 days and the critical hydraulic retention time ($HRT_{Critical}$) for biomass wash out was found to be 9.5 days. Conclusions: The modified Gompertz model could be better in predicting biogas and methane production from SM. The HRT greater than 10 days is recommended for continuous digesters using SM as feedstock.

Evaluation of the Biogas Productivity Potential of Fish Waste: A Lab Scale Batch Study

Kafle, Gopi Krishna,Kim, Sang Hun Korean Society for Agricultural Machinery 2012 바이오시스템공학 Vol.37 No.5

Purpose: The biogas productivity potential of fish waste (FW) was evaluated. Methods: Batch trials were carried out in 1.3 L glass digesters kept in a temperature controlled chambers at $36.5^{\circ}C$. The first order kinetic model and the modified Gompertz model were evaluated for biogas production. The Chen and Hashimoto model was used to determine the critical hydraulic retention time (HRT $_{Critical}$) for FW under mesophilic conditions. The feasibility of co-digestion of FW with animal manure was studied. Results: The biogas and methane potential of FW was found to be 757 and 554 mL/g VS, respectively. The methane content in the biogas produced from FW was found to be 73% and VS removal was found to be 77%. There was smaller difference between measured and predicted biogas production when using the modified Gompertz model (16.5%) than using first order kinetic model (31%). The time period for 80%-90% of biogas production ($T_{80-90}$) from FW was calculated to be 50.3-53.5 days. Similarly, the HRT $_{Critical}$ for FW was calculated to be 13 days under mesophilic conditions. The methane production from swine manure (SM) and cow manure (CM) digesters could be enhanced by 13%-115% and 17%-152% by mixing 10%-90% of FW with SM and CM, respectively. Conclusions: The FW was found to be highly potential substrate for anaerobic digestion for biogas production. The modified Gompertz model could be more appropriate in describing anaerobic digestion process of FW. It could be promising for co-digestion of FW with animal manure.

Tar fouling reduction in wood pellet boiler using additives and study the effects of additives on the characteristics of pellets

Kafle, S.,Euh, S.H.,Cho, L.,Nam, Y.S.,Oh, K.C.,Choi, Y.S.,Oh, J.H.,Kim, D.H. Pergamon Press 2017 ENERGY Vol.129 No.-

Fouling of tar in wood pellet boiler reduces its thermal efficiency and demands periodical maintenance to keep its original performance. The fouling of tar in wood pellet boiler was studied along with the physical and thermal characteristics of the pellets. Four different samples were prepared and accessed: a sample of control pellets without additives and three other samples each with 2% additives (dolomite and/or lime). Experiments for each sample were carried out in the pellet boiler for 20 h and fouling of tar is investigated. It is observed that the fouling of tar is drastically reduced in the pellets with additives 1% dolomite plus 1% lime: 76% by area-density (kg/m<SUP>2</SUP>) and 82% by thickness (mm). At the same time, the particle density, mechanical durability, bulk density, and heating value are also found to be improved leading to an improved overall performance of the pellets and the boiler. The pellets with the additives are, therefore, found to be a better option to reduce tar in wood pellet boilers and are recommended.

Anaerobic digestion of Chinese cabbage waste silage with swine manure for biogas production: batch and continuous study.

Kafle, Gopi Krishna,Bhattarai, Sujala,Kim, Sang Hun,Chen, Lide Taylor Francis ; Publications Division, Selper Ltd 2014 Environmental Technology Vol.35 No.21

<P>The aim of this study was to investigate the potential for anaerobic co-digestion of Chinese cabbage waste silage (CCWS) with swine manure (SM). Batch and continuous experiments were carried out under mesophilic anaerobic conditions (36-38C). The batch test evaluated the effect of CCWS co-digestion with SM (SM: CCWS=100:0; 25:75; 33:67; 0:100, % volatile solids (VS) basis). The continuous test evaluated the performance of a single stage completely stirred tank reactor with SM alone and with a mixture of SM and CCWS. Batch test results showed no significant difference in biogas yield up to 25-33% of CCWS; however, biogas yield was significantly decreased when CCWS contents in feed increased to 67% and 100%. When testing continuous digestion, the biogas yield at organic loading rate (OLR) of 2.0 g VSL?1 d?1 increased by 17% with a mixture of SM and CCWS (SM:CCWS=75:25) (423 mL g?1 VS) than with SM alone (361 mL g?1 VS). The continuous anaerobic digestion process (biogas production, pH, total volatile fatty acids (TVFA) and TVFA/total alkalinity ratios) was stable when co-digesting SM and CCWS (75:25) at OLR of 2.0 g VSL?1 d?1 and hydraulic retention time of 20 days under mesophilic conditions.</P>

Emissions of Odor, Ammonia, Hydrogen Sulfide, and Volatile Organic Compounds from Shallow-Pit Pig Nursery Rooms

Kafle, Gopi Krishna,Chen, Lide Korean Society for Agricultural Machinery 2014 바이오시스템공학 Vol.39 No.2

Purpose: The objective of this study was to measure emissions of gases (ammonia ($NH_3$), hydrogen sulfide ($H_2S$) and carbon dioxide ($CO_2$)), volatile organic compounds (VOC) and odor from two shallow pit pig nursery rooms. Gas and odor reduction practices for swine operations based on the literature were also discussed. Methods: This study was conducted for 60 days at a commercial swine nursery facility which consisted of four identical rooms with mechanical ventilations. Two rooms (room 1 (R1) and room 2 (R2)) with different pig numbers and ventilation rates were used in this study. The pig manure from both the R1 and R2 were characterized. Indoor/outdoor temperatures, ventilation rates/duration, $NH_3$, $H_2S$, $CO_2$, and VOC concentrations of the ventilation air were measured periodically (3-5 times/week). Odor concentrations of the ventilations were measured two times on two days. Three different types of gas and odor reduction practices (diet control, chemical method, and biological method) were discussed in this study. Results: The volatile solids to total solids ratio (VS/TS) and crude protein (CP) value of pig manure indicated the pig manure had high potential for gas and odor emissions. The $NH_3$, $H_2S$, $CO_2$ and VOC concentrations were measured in the ranges of 1.0-13.3, 0.1-5.7, 1600-3000 and 0.0-1.83 ppm, respectively. The $NH_3$ concentrations were found significantly higher than $H_2S$ concentrations for both rooms. The odor concentrations were measured in the range of $2853-4432OU_E/m^3$. There was significant difference in odor concentrations between the two rooms which was due to difference in pig numbers and ventilation duration. The literature studies showed that simultaneous use of dietary control and biofiltration practices will be more effective and environmentally friendly for gas and odor reductions from pig barns. Conclusions: The gas and odor concentrations measured in the ventilation air from the pig rooms indicate an acute need for using gas and odor mitigation technologies. Adopting diet control and biofiltration practices simultaneously could be the best option for mitigating gas and odor emissions from pig barns.