• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.3
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• pp.5-13
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• 2019

This study is conducted to investigate the effects of anaerobic treatments of swine manure slurry alone and combination of livestock manure slurry and fruit pomace on biogas production. Anaerobic co-digestion was evaluated in mesophilic tank reactors for 96 day-incubation period. The organic matter loading of anaerobic digestion was 1 kg of volatile solids(VS) per $1m^3{\cdot}day$. The highest methane production was achieved from the combination of swine manure slury and mandarin pomace(70:30) treatment, whereas the lowest daily and cumulative methane yields was observed in swine manure slurry alone treatment. More than two-fold increase in bio-gas and methane production was obtained by combination of livestock manure slurry and mandarin pomace treatment, compared to the swine manure slurry alone treatment. The co-digestion of livestock manure and fruits pomace has advantages to enhance the production of methane gas, compared to digestion of swine manure slurry alone.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6B
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• pp.669-675
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• 2006

Intermittent aerobic digestion experiments using a sequencing batch reactor (SBR) were carried out in this study. Aeration ratio was found to be an important operation factor for the reduction of solids and nitrogen. As the sludge digested, organic nitrogen was released from the solids and oxidized to nitrate nitrogen. Biological denitrification was also significant and the denitrification rate was limited by aeration ratio. Under the condition of 0.25-0.75 of aeration ratio, acclimation of ammonia nitrogen was not observed and pH were preserved near neutral in the intermittent aerobic digestion. As the aeration ratio increased, solids reduction was increased whereas dissolved nitrogen removal was decreased. Based on the experiments, 17-2% of VSS reduction and over 80% of dissolved nitrogen removal were practicable by intermittent aerobic digestion using a SBR when the MSRT were designed 8-32 days and aeration ratio was operated about 0.25-0.75.

• Preventive Nutrition and Food Science
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• v.6 no.3
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• pp.180-186
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• 2001

Bone marrow cell proliferating arabinogalactan-like polysaccharide (ALR-3IIa-1-1) has been purified from rhizomes of Atractylodes lancea DC. In order to characterize the essential structure of ALR-3IIa-1-1 for expression of the activity, sequential enzymatic digestion using ego-$\alpha$-L-arabinofurasidase (AFase) and ego-$\beta$-D-(1longrightarrow3)-galactanase (GNase) was employed. After ALR-3IIa-1-1 was digested with the AFase, the GNase digestion cleaved only 10% and 23% of 3-linked and 3,6-branched galactose, respectively, from arabinose-trimmed ALR-3IIa-1-1 (AT-ALR-3IIa-1-1), and gave small amounts of intermediate size (AT-G-2) and shorter oligosaccharides (AT-G-3) fractions in addition to a large amount of the GNase resistant fraction (AT-G-1). When AT-G-1 was redigested gradually with the AFase and GNase, it released trace amounts of oligosaccharides in addition to a large amount of the resistant fraction. When the final enzyme-resistant fraction from AT-G-1 was digested simultaneously with both AFase and GNase, the resistant fraction was significantly degraded into two long fragments (3AT-3G-1 and 2). The mixture of digestion products from the first GNase digestion of AT-ALR-3IIa-1-1 showed a significantly decreased bone marrow cell proliferation activity to about 30% of the activity of ALR-3IIa-1-1, but the GNase resistant fraction (AT-7-1) still had significant activity. Although the second gradual enzymatic digestion of AT-G-1 showed a marginal decrease in activity, the resulting fragments (3AT-3G-1 and 2) by the final simultaneous enzymatic digestion lost most of the activity. Component sugar, methylation and FAB-MS analyses indicated that the digestion products (AT-G-21 AT-G-31 2AT-2G-2 and 2AT-2G-3) released from AT-ALR-3IIa-1-1 by the sequential enzymatic digestion contained galactose-containing oligosaccharides mainly comprising 6-linked galactose, that some of which were partially arabinosylated, and these oligosaccharides were attached to $\beta$-D-(1longrightarrow3)-galactan backbone in its non-reducing terminal side as side chains.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.8
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• pp.1152-1159
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• 2013

Four male lambs (Katahdin; average live weight $25.9{\pm}2.9$ kg) with "T" type cannulas in the rumen and proximal duodenum were used in a $4{\times}4$ Latin square experiment to evaluate the influence of supplemental dry distillers grain with solubles (DDGS) levels (0, 10, 20 and 30%, dry matter basis) in substitution for dry-rolled (DR) corn on characteristics of digestive function and digestible energy (DE) of diet. Treatments did not influence ruminal pH. Substitution of DR corn with DDGS increased ruminal neutral detergent fiber (NDF) digestion (quadratic effect, p<0.01), but decreased ruminal organic matter (OM) digestion (linear effect, p<0.01). Replacing corn with DDGS increased (linear, $p{\leq}0.02$) duodenal flow of lipids, NDF and feed N. But there were no treatment effects on flow to the small intestine of microbial nitrogen (MN) or microbial N efficiency. The estimated UIP value of DDGS was 44%. Postruminal digestion of OM, starch, lipids and nitrogen (N) were not affected by treatments. Total tract digestion of N increased (linear, p = 0.04) as the DDGS level increased, but DDGS substitution tended to decrease total tract digestion of OM (p = 0.06) and digestion of gross energy (p = 0.08). However, it did not affect the dietary digestible energy (DE, MJ/kg), reflecting the greater gross energy content of DDGS versus DR corn in the replacements. The comparative DE value of DDGS may be considered similar to the DE value of the DR corn it replaced up to 30% in the finishing diets fed to lambs.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.1
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• pp.90-96
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• 2008

In order to meet the stringent requirement of sludge disposal and to find ecological alternative, aerobic digestion coupled with alkaline pretreatment was studied. The treated sludge was tested for the potential of liquid fertilizer. In the aerobic digestion, it was obvious that the performance of digester B(fed with the sludge pretreated by NaOH) was better than that of digester A(fed with raw sludge) in terms of COD and SS removal. SS and VSS removal rates in digester B were 66% and 69%, respectively. At 5 days, TSS removal rate reached 47% in the digester B, which was 71% of final TSS removal rate. It revealed that the pretreatment process can shorten the retention time of aerobic digestion. 94.1% of TCOD in the raw sludge was reduced by alkaline pretreatment and aerobic digestion. Final SCOD was in the range of 220$\sim$230 mg/L implying the sludge was stabilized. Nitrification and pH drop were observed in the aerobic digestion. Final nitrate concentrations in digester A and B were 445.4 and 223.1 mg/L and final pH in digester B was 3.0. Biological assays reported that leaf size of cucumber seedling increased with nitrate concentration and sludge to soil ratio. The sludge treated by alkaline and aerobic digestion promoted the growth of seedling leaf and stem remarkably compared to raw sludge. In contrast, the aerobically digested sludge without pretreatment improved leaf growth and inhibited stem growth.

• Korean Chemical Engineering Research
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• v.48 no.1
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• pp.103-109
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• 2010

Anaerobic digestion has been widely used for the treatment of sludge, which is generated from the municipal and industrial wastewater treatment, for its volume reduction and methane production. Many researches on sludge pre-treatment have been carried out in order to enhance the performance of anaerobic digestion by increasing the hydrolysis of sludge which is the rate limiting step of anaerobic digestion. In this study, the effect of pre-treatment on sludge hydrolysis(solubilization), methane production and sludge reduction by anaerobic digestion after thermal, ultrasonic, and thermal-alkali sludge treatment were compared. Thermal-alkali treatment showed 67 and 70% solubilization with municipal and industrial wastewater sludge, respectively, while ultrasonic treatment and thermal treatment gave similar solubilization efficiency of 40% or more. Methane content of the anaerobic digestion gas reached 45~70% and pretreated sludge gave higher methane content than the control sludge. Methane production of thermal, ultrasonic, and thermal-alkali pre-treatment gave 2.6, 2.7, 3.5 times of municipal control sludge and 3.5, 4.1, 4.2 times of industrial control sludge, respectively. Sludge reduction of pre-treated sludge after anaerobic digestion gave 5~19% point higher than that of control sludge, and thermal-alkali treatment showed higher reduction efficiency than thermal and ultrasonic treatment. The results proved that pre-treatment contributed significantly not only for the methane production but also for the cost reduction of sludge treatment and disposal, and thermal-alkali treatment gave the best performance for the sludge treatment.

• Applied Chemistry for Engineering
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• v.28 no.5
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• pp.581-586
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• 2017

In this study, in order to find the feasibility of thermophilic biological pre-treatment for the co-digestion of food wastewater and sewage sludge, digestion efficiency of the combined thermophilic aerobic and mesophilic anaerobic process and its effect on methane production were investigated. Also, a lab-scale co-digestion process was operated to observe parameter changes according to the increase of organic loading rates using different dilution ratios of distilled water and food wastewater (1/3 [Run I], 2/3 [Run II] in addition to using the raw food wastewater [Run III]). The results indicated that co-digestion process maintained quite stable and constant pH during entire experiments. With regard to VS removal, the higher removal was observed in the combined process and the removal efficiency was 52.24% (Run I), 66.59% (Run II) and 72.53 (Run III), respectively. In addition, the combined process showed about an 1.6-fold improved methane production rate and significantly higher methane yield than that of using single anaerobic digestion process.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.351-352
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• 1989

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.292-294
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• 1989

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.7
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• pp.965-973
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• 2011

Our objective was to determine the differences in the rate and extent of dry matter digestion between barley subjected to differing agronomic variables. Two malting barley varieties, Copeland and Metcalfe were seeded at rates of 200 and 400 plants/$m^2$. Each of these varieties received nitrogen fertilizer at rates of 0, 30, 60 and 120 kg/ha, resulting in a total of 20 different barley grain samples. Samples were ground through a 6mm screen and approximately 3 g of each weighed into 50 ${\mu}m$ Dacron bags and sealed. The bags were incubated in three ruminally cannulated Holstein cattle for periods of 0, 3, 6 and 24 h. Using the data obtained from these incubations, rates of digestion were able to be predicted. The soluble fraction ranged from 0.229-0.327, the slowly degradable fraction ranged from 0.461-0.656, and the undegradable fraction ranged from 0.038-0.299. The rates of digestion ranged from 0.127-0.165 $h^{-1}$ and the effective degradability ranged from 0.527-0.757. At the Canora location, the Copeland samples which received 120 kg/ha of nitrogen fertilizer had a significantly lower (p = 0.013) soluble fraction than the rest of the samples at that location. A significant interaction (p = 0.009) was seen between the seeding rate and nitrogen fertilizer application with samples from the Canora location, as well as significant differences (p = 0.029) between nitrogen application rates in samples from the Indian head location. The rate of digestion of samples from the Indian head location differed (p = 0.020) between the two seeding rates, with samples seeded at 200 seed/$m^2$ having a slightly higher rate of degradation. Differences in the effective degradability were seen between the different nitrogen application rates with samples from both the Canora and Indian head locations, as well as an (p = 0.004) interaction between the seeding rate and nitrogen fertilizer application rate. Although there was not a clear correlation between the different variables, both nitrogen application and seeding rate did have a significant effect on the rates and extent of digestion across each of the four locations.