• Journal of the Korean Wood Science and Technology
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• v.52 no.4
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• pp.363-374
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• 2024

Nyamplung (Calophyllum inophyllum L.) seeds, which account for 40% of the fruit, have been used as a raw material for biofuels, and the seed shells remaining after their extraction are wasted. In this study, we investigated the potential of waste Nyamplung seed shells in the form of pellets as a biomass energy resource. A completely randomized research design was implemented to evaluate the effects of torrefaction and heat treatment on the quality of produced pellets. Two observed treatments, namely, particle size (0.18-0.25, 0.25-0.43, and 0.43-0.84 mm) and torrefaction temperature (200℃, 225℃, and 250℃), were investigated. Our results showed that the calorific value of torrefied Nyamplung seed-shell pellets ranged from 4,245.60 to 4,528.00 cal/g, fulfilling the Indonesia Nasional Standard (≥ 4,000 cal/g). The quality of pellets were the best when produced from raw materials with a particle size of 0.18-0.25 mm and torrefaction temperature of 225℃. Thus, we concluded that waste Nyamplung seed shells are a good raw material for the production of pellets.

• Journal of Biosystems Engineering
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• v.43 no.1
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• pp.59-71
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• 2018

Purpose: Cellulose nanocrystals (CNCs) are natural polymers that have been promoted as a next generation of new, sustainable materials. CNCs are invaluable as reinforcing materials for composites because they can impart improved mechanical, chemical, and thermal properties and they are biodegradable. The purpose of this review is to provide researchers with information that can assist in the application of CNCs extracted from waste agricultural byproducts (e.g. rice husks, corncobs, pineapple leaves). Methods & Results: This paper presents the unique characteristics of CNCs based on agricultural byproducts, and lists processing methods for manufacturing CNCs from agricultural byproducts. Various mechanical treatments (microfluidization and homogenization) and chemical treatments (alkali treatment, bleaching and hydrolysis) can be performed in order to generate nanocellulose. CNC-based composite properties and various applications are also discussed. Conclusions: CNC-based composites from agricultural byproducts can be combined to meet end-use applications such as sensors, batteries, films, food packaging, and 3D printing by utilizing their properties. The review discusses applications in food engineering, biological engineering, and cellulose-based hydrogels.

• Journal of the Korean Wood Science and Technology
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• v.43 no.5
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• pp.548-557
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• 2015

This study investigated environmental assessments of leachate containing formaldehyde from medium density fiberboard (MDF) disposed in laboratory-scale simulated landfills. Environmental impact assessment of leachate was conducted by measuring formaldehyde, toxicity, biochemical oxygen demand (BOD), chemical oxygen demand (COD), bacterial enumeration, and pH. Amount of formaldehyde in leachate from MDF in soil decreased to the level of soil only treatment by 28 days, and toxicity decreased as the amount of formaldehyde decreased. BOD and COD levels in leachate from the treatments containing MDF exceeded permissible discharge levels of BOD or COD throughout the experimental period. The pH levels of all treatment were within permissible discharge range except on day 0. Fewer bacteria were observed in leachate from MDF in soil treatment than other treatments (MDF only, cured UF resin in soil, and soil only). Consequently, the leachate from disposal of MDF in soil detrimentally affect on environment. However, soil buffered formaldehyde leaching and pH on leachate in this study. Waste MDF may be required the pre-water soaking treatment for leaching formaldehyde to reclaim on land.

• International journal of advanced smart convergence
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• v.5 no.2
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• pp.18-23
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• 2016

Cell walls of microalgae consist of a polysaccharide and glycoprotein matrix providing the cells with a formidable defense against its environment. Anaerobic digestion (AD) of microalgae is primarily inhibited by the chemical composition of their cell walls containing biopolymers able to resist bacterial degradation. Adoption of pre-treatments such as thermal, thermal hydrolysis, ultrasound and enzymatic hydrolysis have the potential to remove these inhibitory compounds and enhance biogas yields by degrading the cell wall, and releasing the intracellular algogenic organic matter (AOM). This paper preproposal stage investigated the effect of different pre-treatments on microalgae cell wall, and their impact on the quantity of soluble biomass released in the media and thus on the digestion process yields. This Paper present optimum approach to degradation of the cell wall by ultra-sonication with practical design specification parameter for ultrasound based pretreatment system. As a result of this paper presents, a microalgae system in a wastewater treatment flowsheet for residual nutrient uptake can be justified by processing the waste biomass for energy recovery. As a conclusion on this result, Low energy harvesting technologies and pre-treatment of the algal biomass are required to improve the overall energy balance of this integrated system.

• Korean Journal of Agricultural Science
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• v.51 no.1
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• pp.41-51
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• 2024

This study explored the effect of increased feed intake during the late gestation on the reproductive performance of sows, and fecal score in sows and piglets. A total of 21 crossbred [Landrace × Yorkshire] multiparous sows were randomly distributed into three treatments with seven replicates per treatment. Treatments: CON, 2.4 kg/day; TRT1, 3.2 kg/day; TRT2 , 3.6 kg/day. Body weight and body condition score of sow in different stages were not altered (p > 0.05) due to extra feed in late gestation. A linearly higher (p < 0.05) difference in backfat thickness during farrowing was found in this study. Average daily feed intake was increased (p < 0.05) linearly with extra feed in this experiment. The weaning body weight of piglets was increased (p < 0.05) with extra feed in the sow. The fecal score of sows and their piglets was similar (p > 0.05) in different levels of feed intake. In conclusion, extra feed to gestation sow showed a beneficial effect on improving the weaning piglet's body weight. Although there is a small improvement in the body weight of weaning pigs of sow fed 3.6 kg feed/day in the late gestation period, it is unlikely to be profitable enough to justify the additional waste of feed.

• Korean Journal of Poultry Science
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• v.33 no.3
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• pp.217-224
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• 2006

This study was carried out to investigate the effect of food-waste(FW) between weeks(0, 1, 2, 3, 4 week) and additive levels(0, 1, 3, 5, 10, 20%) on egg production and egg qualify in laying hens. One hundred sixty two White Leghorn laying hens at fifty weeks of age were used for this work. There was no significant difference on feed intake, egg production, and egg weight among all treatments. But, 20% FW group was decreased at 1, 2, and 3 week on egg production and it was recovered at 4 weeks(p<0.05). There was no difference on the eggshell thickness and egg yolk index among all treatments. However, eggshell breaking strength were $4.13kg/cm^2\;and\;4.04kg/cm^2$ at 3 week and 4 week, individually, and there was difference on eggshell breaking strength(p<0.05). Haugh unit and egg yolk color were high at 20% FW group as 92.3 and 9.4, individually, and there was shown the significant increasing in weeks and additive levels(p<0.05). Conclusionally, 20% FW group was decreased on egg production, while 5% FW group was maintained on egg production, and haugh unit and egg yolk color were cleary developed. Therefore, if the nutrients balance of FW diets were controlled, FW diets will be used with one of the valuable feed sources.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.12
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• pp.1095-1104
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• 2009

The objective of this research was to evaluate the feasibility of using oyster-shell and eggshell wastes for the stabilization of arsenic-contaminated soil. Artificial As(V) contaminated soil was mixed with 0~5% oyster-shell and eggshell wastes and each sample was incubated for 30 days in a controlled environment. The efficiency of each treatment was evaluated using various single extractants (1 N HCl, 0.1 N NaOH and 0.5 N $H_2SO_4$). The concentration of As(V) was reduced by 10% upon a 5% oyster-shell or eggshell waste treatments based on the Korea Standard Test method (1 N HCl extraction). Analogous trends were observed in the 0.1 N NaOH or 0.5 N $H_2SO_4$ extractions. In addition, the oyster-shell and eggshell waste treatments increased the pH of each soil from 6.54 (Control) to 7.62~7.94. The exchangeable Ca in each soil also sharply increased from 6.87 cmol(+)/kg (Control) to 12.77~20.18 cmol(+)/kg. Further research is needed to increase the effectiveness of the oyster-shell and eggshell waste for the stabilization of As(V) in the contaminated soil.

• Korean Journal of Environmental Agriculture
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• v.20 no.1
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• pp.8-14
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• 2001

To investigate the effects of waste sludge from antibiotic fermentation on the growth of young radish and chemical properties of soil, five levels of fertilizer, control (recommended fertilizer, $N-P_2O_5-K_2O=160-59-104$ kg/ha), AS(control + sludge 1,000 kg/ha), AC(control + conventional compost 1,000 kg/ha), SNS(control - subtracting 30% N of sludge + sludge 1,000 kg/ha) and SNC(control - subtracting 30% N of conventional compost + conventional compost 1,000 kg/ha) were applied and radish was grown twice with same treatments on May and August in 1998. Germination rate and early growth of young radish grown with AS and SNS were lower than those grown in control and with AC, SNC. This negative effects by adding the sludge in the early growth seemed to be caused by damage of ammonia gas released during degradation of the sludge in soil. However, yield of young radish showed no significant difference among all the treatments including the AS and SNS at the 1st and 2nd experiment, and these suggested that the latter half of growth of young radish was accelerated by adding the sludge. Contents of T-N in young radish and inorganic N in soil showed a tendency to increase by adding the sludge while antibiotic substance, cephalosporin-C, was not detected in plant material and soils after harvest of young radish in both experiments. Consequently, waste sludge from antibiotic fermentation, which contains high levels of organic matter and nitrogen could be used as an useful resource in agriculture.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.2
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• pp.185-192
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• 2010

The objective of this study was to investigate the effectiveness of stabilization for army firing range soil highly contaminated with Pb (total Pb: 29,000 mg/kg) using calcined waste oyster shells. The calcination was conducted to activate quicklime from calcite. In order to evaluate the effectiveness of calcination, both natural oyster shells (NOS) and calcined oyster shells (COS) were applied to the Pb contaminated soil. Stabilization was conducted by mixing the contaminated soil with oyster shell media at 5-20 wt% and cured for 28 days. Following 28 days of curing, Pb leachability was measured based on the Korean Standard Test method (0.1 N HCl extraction). The treatment results showed that the COS treatment outperformed the NOS treatment. All of the NOS treatments failed to meet the Korean warning standard of 100 mg/kg. However, the Pb concentrations were significantly reduced to 47 mg/kg and 3 mg/kg upon 15 wt% and 20 wt% COS treatments, respectively which passed the Korean warning standard. Moreover, -#20 mesh materials were more effective than the -#10 mesh materials in effectively reducing Pb leachability. The scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX) results indicated that Pb immobilization was strongly linked to Al and Si.

• Animal Bioscience
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• v.36 no.10
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• pp.1612-1618
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• 2023

Objective: In our previous study, we observed that the addition of waste cooking oil (WCO) reduced ammonia (NH₃) emissions during laboratory-scale composting of dairy cattle manure under low-aeration condition. Therefore, this study aimed to evaluate the effect of addition of WCO on NH₃ emissions reduction during pilot-scale composting of dairy cattle manure, which is close to the conditions of practical composting treatment. Methods: Composting tests were conducted using pilot-scale composting facilities (1.8 m³ of capacity). The composting mixtures were prepared from manure, sawdust, and WCO. Two treatments were set: without WCO (Control) and with WCO added to 3 wt% of manure (WCO3). Composting was conducted under continuous aeration at 40 L/min, corresponding to 22.2 L/(min·m³) of the mixture at the start of composting. The changes in temperatures, NH₃ concentrations in the exhaust gases, and contents of the composted mixtures were analyzed. Based on these analysis results, the effect of WCO addition on NH₃ emissions and nitrogen loss during composting was evaluated. Results: During composting, the temperature increase of the composting mixture became higher, and the decreases of weight and water content of the mixture became larger in WCO3 than in Control. In the decrease of weight, and the residual weight and water content of the mixture, significant differences (p<0.05) were detected between the two treatments at the end of composting. The NH₃ concentrations in the exhaust gases tended to be lower in WCO3 than in Control. Nitrogen loss was 21.5% lower in WCO3 than in Control. Conclusion: Reduction of NH₃ emissions by the addition of WCO under low aeration condition was observed in pilot-scale composting, as well as in laboratory-scale composting. This result suggests that this method is effective in reducing NH₃ emissions in practical-scale composting.