• 에너지공학
• /
• 제29권3호
• /
• pp.34-41
• /
• 2020

Used disposable diapers have been considered for a long time as a type of waste difficult to recycle and valorize due to their composite nature including plastic, cellulose pulp, a super absorbent polymer and either urine, feces or both. Therefore, the fate of disposed diapers often is either incineration or landfill burial which both have various adverse environmental impacts. However, used disposable diapers contain nutrients: cellulose is an organic matter while urine and feces contain non negligible amounts of nitrogen, phosphorus and potassium which are primary nutrients included in most chemical fertilizers used in agriculture. In a scope of waste recycling and valorization, this study focuses on developing a method to achieve nutrient solution extraction from used disposable diapers. The experiment essentially consists in shredding the diapers and letting them macerate in solutions of sodium hydroxide with various concentrations to allow breaking down of the cellulose and super absorbent polymer and release of urine and feces before sterilizing the solutions in an autoclave to remove potential coliform bacteria. At the end of the experiment, a set of parameters is measured for the final solution to identify concentrations of nutrients as well as presence or absence of harmful substances. Results are discussed and directions for future studies are suggested, which include mechanization of the diapers shredding process or added aeration to enhance nitrification and absorption of extracted nutrients from plants.

• Asian-Australasian Journal of Animal Sciences
• /
• 제14권8호
• /
• pp.1144-1148
• /
• 2001

The implications of incorporating deoiled rice bran (DORB) in diet on the utilization of certain nutrients had been examined through balance studies made with 6- and 10- week-old Japanese quails. The stuffs evaluated in this study had their origin from two different types of processes- a batch extraction (DORB-B) and another continuous process (DORB-C), and each included at 10, 20 or 30% level in an iso-nitrogenous and iso-caloric diet. On chemical analyses, the DORB-B was found to contain crude protein, 19.0; ether extract, 0.79; total ash, 17.05; Ca, 0.11; P, 1.92; glucose, 2.35 and starch 11.22 g/100 g day matter. Corresponding values for DORB-C were 15.02, 1.56, 13.0, 0.40, 2.76, 2.16 and 19.0, respectively. The data on nutrient balances with quails fed diets containing the two-types of DORB suggested no significant (p>0.05) differences in per cent retention of diet dry matter (DM), organic matter (OM), ether extract (EE), gross energy (GE), nitrogen (N), crude fiber (CF), calcium (Ca) or phosphorus (P) content attributable to the extraction process. The age of the birds also appeared to have no significant (p>0.05) effect on nutrient utilization by them. However, the level of inclusion of DORB had a significant (p<0.05) effect on nutrient utilization by quails in that the retention of dietary N, EE, CF, Ca and P was better at lower than at higher levels. It is concluded that the DORB, irrespective of extraction process, can safely be employed upto 20% level in diet of adult Japanese quails without noticeable interference in utilizing the major dietary nutrients.

• Preventive Nutrition and Food Science
• /
• 제7권1호
• /
• pp.12-17
• /
• 2002

Simultaneous determination of nine water-soluble vitamins contained in multi-nutrient tablets was carried out by reversed phase high-performance liquid chromatography (RP-HPLC) equipped with analytical $C_{18}$ column and UV (270 nm) detector. Those standard vitamins were successfully separated within 23 minutes by gradient elution with solvent A (0.5 M potassium phosphate monobasic) and solvent B (0.25 M potassium phosphate monobasic-methanol, 1:1). Calibration curves showed good linealities with correlation coefficients (> 0.92) in tested ranged respectively. The detection limits were considered to be 2.1 ng for ascorbic acids 60 ng for Vit B$_{6}$ 3 ng for p-aminobenzoic acid, 9 ng for niacinamide, 9 ng for thiamin, 5.0 ng for folic acid and 1.5 ng for riboflavin at 0.05 a.u.f.s. Solid phase extraction through Sep-Pak (C$_{18}$ ) cartridge was successfully applied for purification of water soluble vitamins in commercial multi-nutrient tablets.ts.

• Environmental Engineering Research
• /
• 제21권3호
• /
• pp.265-275
• /
• 2016

In this study, the microalga Neochloris oleoabundans was cultivated in a sustainable manner using diluted anaerobic digestate to produce biomass as a potential biofuel feedstock. Prior to microalgae cultivation, the anaerobic digestate was characterized and several pretreatment methods including hydrogen peroxide treatment, filtration, and supernatant extraction were investigated and their impact on the removal of suspended solids as well as other organic and inorganic matter was evaluated. It was found that the supernatant extraction was the most convenient pretreatment method and was used afterwards to prepare the nutrient media for microalgae cultivation. A bench-scale experiment was conducted using multiple dilutions of the supernatant and filtered anaerobic digestate in 16 mm round glass vials. The results indicated that the highest growth of the microalga N. oleoabundans was achieved with a total nitrogen concentration of 100 mg N/L in the 2.29% diluted supernatant in comparison to the filtered digestate and other dilutions.

• 농촌계획
• /
• 제8권1호
• /
• pp.60-68
• /
• 2002

A Modified CREAMS model, CREAMS-PADDY was developed to simulate the hydrology and nutrient transport at an irrigated rice paddy. The hydrology at a paddy was simulated by a daily water balance routine which reflects daily inflow, outflow, and water level changes. The soil erosion was simulated using modified USLE. The nutrient transport for total nitrogen and phosphorus were depicted for various phases of each constitute such as extraction, percolation, mineralization, and plant uptakes. Field monitoring was conducted to investigate the water quality changes at a paddy field at three times a week during the growing season of 1996. The proposed model simulates the water quality of the paddy reasonably well, and is found to be applicable to field conditions.

• Journal of Microbiology and Biotechnology
• /
• 제3권2호
• /
• pp.115-122
• /
• 1993

Poly(3-hydroxybutyrate)(P(3HB)) accumulation under nutrient-rich condition with various amounts of $(NH_4)_2 SO_4$ was systematically investigated. The results of the electron-microscopy and the solvent extraction showed that the P(3HB) accumulation is unavoidable even under nutrient-rich condition. This indicates that in a two-step culture of Alcaligenes eutrophus H16, the researches should be careful in interpreting the data of polyhydroxyalkanoates(PHAs) accumulation in terms of the carbon-source fed in the second step because the two-step culture product contains the P(3HB) produced under nutrient-rich condition. The polyester production capability in a two-step batch culture of A. eutrophus H16(ATCC 17699) was also investigated using various saccharides and their derivatives such as glucose, fructose, gluconic acid, glucaric acid, sorbitol, lactose, galactose, and mannose. The polyesters synthesized were characterized by 500 MHz$^{1}H-NMR$ spectroscopy, intrinsic viscosity$[\eta]$ measurement in chloroform and differential scanning calorimetry(DSC). 500 MHz $^{1}H-NMR$ analysis showed that all polyesters synthesized generally contained 1~2 mol% of 3HV. Another finding is that the glucose utilization can be increased by changing the autoclaving procedure of the substrate to enhance the P(3HB) production yield up to 46 wt% of P(3HB) in dry cells.

• Journal of Biosystems Engineering
• /
• 제31권6호
• /
• pp.463-473
• /
• 2006

Automated sensing of soil macronutrients would allow more efficient mapping of soil nutrient spatial variability for variable-rate nutrient management. The capabilities of ion-selective electrodes for sensing macronutrients in soil extracts can be affected by the presence of other ions in the soil itself as well as by high concentrations of ions in soil extractants. Adoption of automated, on-the-go sensing of soil nutrients would be enhanced if a single extracting solution could be used for the concurrent extraction of multiple soil macronutrients. This paper reports on the ability of the Kelowna extractant to extract macronutrients (N, P, and K) from US Corn Belt soils and whether previously developed PVC-based nitrate and potassium ion-selective electrodes could determine the nitrate and potassium concentrations in soil extracts obtained using the Kelowna extractant. The extraction efficiencies of nitrate-N and phosphorus obtained with the Kelowna solution for seven US Corn Belt soils were comparable to those obtained with IM KCI and Mehlich III solutions when measured with automated ion and ICP analyzers, respectively. However, the potassium levels extracted with the Kelowna extractant were, on average, 42% less than those obtained with the Mehlich III solution. Nevertheless, it was expected that Kelowna could extract proportional amounts of potassium ion due to a strong linear relationship ($r^2$ = 0.96). Use of the PVC-based nitrate and potassium ion-selective electrodes proved to be feasible in measuring nitrate-N and potassium ions in Kelowna - soil extracts with almost 1 : 1 relationships and high coefficients of determination ($r^2$ > 0.9) between the levels of nitrate-N and potassium obtained with the ion-selective electrodes and standard analytical instruments.

• 생물환경조절학회지
• /
• 제5권2호
• /
• pp.167-173
• /
• 1996

1. 레이저변위계 및 x-y로봇을 이용하여 계측한 3차원 데이터를 컴퓨터실의 PC/AT에 데이터를 전송하고, Visual Basic(Microsoft)을 이용하여 프로그램화한 화상처리시스템에 의해 머스크멜론 네트의 추출과 그 특징을 확인할 수 있었다. 2. 시용 배양액농도 및 배양액 시용시기를 다르게 함으로써 네트의 높이 및 폭의 차이를 확인하는 것이 가능했다. 3. 머스크멜론 네트의 특징인 높이 및 폭은 시용 배양액농도에 따라서 각각 다르다는 것을 알 수 있었다. 배양액의 농도가 낮을수록 네트의 점유율은 낮아지고, 폭은 넓어지는 경향이 보였다.

• ALGAE
• /
• 제17권3호
• /
• pp.187-194
• /
• 2002

A seaweed biofilter/production system of being developed to reduce the environmental impact of marine fish farm effluent in coastal ecosystems as a part of an integrated aquaculture system. Several known seaweed taxa and their cultivars have been considered as candidate biofilter organisms based on their species-specific physiological properties such as nutrient uptake kinetics and their economic value. Porphyra is an excellent cadidate and shows efficient nutrient extraction properties. Rates of ammonium uptake were maintained at around 3 ${\mu}moles{\cdot}g{\cdot}dw^{-1}{\cdot}min^{-1}$ at 150 ${\mu}M$ inorganic nitrogen at $10^{\circ}C$. Ulva is another possible biofilter candidate with an uptake rate of 1.9 ${\mu}moles{\cdot}g{\cdot}dw^{-1}{\cdot}min^{-1}$ under same conditions. A simple uptake/growth and harvest model was applied to estimate the efficiency of the biofilter/production system. The model was deterministic and used a compartment model structure based on difference equations. The efficiency of Porpyra filter was estimated over 17% of ${NH_4}^+$ removal from the contimuous supply of 100 ${\mu}mole{\cdot}l^{-1}\;{NH_4}^+\;at\;100l{\cdot}sec^{-1}$ flow rate.

• Journal of Ginseng Research
• /
• 제34권1호
• /
• pp.68-75
• /
• 2010

This study sought to optimize the extraction and enzymatic treatment conditions of Panax ginseng leaves, stems, and roots for the production of fermented ginseng. The optimization enhanced the extraction of total saccharide, a nutrient and growth-activating factor for Lactobacillus bacteria. The hydrolysis of ginseng leaves, stems, and roots was tested with eight enzymes (Pentopan, Promozyme, Celluclast, Ultraflo, Pectinex, Ceremix, Viscozyme, and Tunicase). The enzymatic hydrolysis conditions were statistically optimized by the experimental design. Optimal particle size of ginseng raw material was <0.15 mm, and optimal hydrolysis occurred at a pH of 5.0-5.5, a reaction temperature of 55-$60^{\circ}C$, a Ceremix concentration of 1%, and a reaction time of 2 hr. Ceremix produced the highest dry matter yield and total saccharide extraction. Ginseng leaves were found to be the most suitable raw material for the production of fermented ginseng because they have higher carbohydrate and crude saponin contents than ginseng roots.