• 대한환경공학회지
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• 제36권4호
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• pp.265-270
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• 2014

영양 성분을 함유하고 있는 유기성 폐기물은 미생물에 의해 처리되어, 유용한 물질로 전환될 수 있다. 이러한 생물학적 공정에서 미생물 세포와 효소는 원료 물질인 기질과 함께 중요하다. 대규모화 공정에서도 미생물 세포와 효소는 공정 최적화에서 필수적인 요소이다. 본 연구에서는 이러한 생물학적 공정의 효율성을 높이는 목적으로 다량의 아미노산과 단백질을 함유하고 있는 많은 종류의 부패가 진전된 유기성 폐기물과 발효 식품에서 단백질 분해효소를 생산하는 미생물을 분리하였다. 단백질 분해 효소의 활성, 온도와 산도등 활성 조건과 활성 정도를 확인하여 선택된 균주들을 동정하였다. 산업적으로 저온에서 단백질을 분해하는 효소는 유기성 폐기물을 저온에서 처리할 수 있다. 저온에서 처리가 가능하다는 것은 폐기물의 처리 온도를 낮은 상태로 유지할 수 있어 그 만큼의 열(steam)비용을 줄일 수 있다. 또한 이 단백질 분해효소를 이용하여 단백질을 분해 후 다량의 아미노산을 생산할 수 있으므로 아미노산 생산 공정에도 적용이 가능하다. 이렇게 유기 폐기물을 처리하여 다양한 용도로 사용할 수 있으므로, 폐기물의 가치를 높일 수 있다. 다양한 활성 조건에서 단백질 분해효소를 다량으로 생산하는 균주를 분리하여 동정하고, 균주 배양 조건, 효소 생산의 최적 조건에 대한 연구를 수행하였다.

• Biomaterials and Biomechanics in Bioengineering
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• 제4권1호
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• pp.21-32
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• 2019

Eggshell is a waste material after the usage of egg. In this work, biowaste chicken eggshells were used for preparing carbonated hydroxyapatite (HA) nanoparticles of high purity through aqueous precipitation method at room temperature. The eggshell-derived HA will be a cost-effective bioceramics for biomedical applications and an effective material-recycling technology. Additionally, mulberry leaf extract was used as a template to regulate the morphology, size and crystallinity of HA, and the effects of pH value were also examined. Characterization of the samples was performed by X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. Scanning electron microscopy (SEM) was used to determine the size, shape and morphology of HA. The results indicate that only one phase of HA were synthesized in the both absence and presence of mulberry leaf extract at pH of 7 and above, while DCPD or DCPA/DCPD phase was observed at pH 4 condition. The crystallite sizes of the HA samples obviously decreased when adding mulberry leaf extract as a template, while they decreased gradually as the solution pH levels increased. With increasing pH level from 7 to 14, the rod-like HA nanoparticles gradually changed to spherical shape at pH 14. Note that, the obtained product is Mg and Sr containing A- and B-type carbonate HA at alkaline pH and it can be a potential material for biomedical applications.

• 한국응용과학기술학회지
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• 제40권1호
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• pp.179-187
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• 2023

바이오물질을 포함하는 나노발전기는 무공해 에너지원이며 생분해성 전자폐기물이라는 점에서 친환경적인 전자소자이다. 특히 바이오 물질이 바이오폐기물로부터 추출될 수 있다면 바이오폐기물의 양도 줄어들 것이다. 본 연구에서는 포유동물의 피부에 존재하는 동물성 콜라겐을 이용하여 마찰전기 나노발전기를 제작하였고 그 특성평가를 진행하였다. 마찰전기 나노발전기의 전기적 양극층은 회전 도포방법을 이용하여 콜라겐 막을 형성하여 구성하였으며, 주사전자현미경으로 막이 다공성임을 확인하였다. 제작한 마찰전기 나노발전기는 주기적인 기계적 운동에 의해 3 Hz에서 7 V부터 5 Hz에서 15 V의 개방전압과 5 Hz에서 3.8 ㎂의 단락전류를 보였다. 결론적으로, 콜라겐 함유 마찰전기 나노발전기는 센서와 같은 저전력 구동 장치의 전원이 될 수 있으며 전자 폐기물 감소에도 유용할 것으로 기대된다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.172-172
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• 2011

Anaerobic digestion(AD) has successfully been used for many applications that have conclusively demonstrated its ability to recycle biogenic wastes. AD has been successfully applied in industrial waste water treatment, stabilsation of sewage sludge, landfill management and recycling of biowaste and agricultural wastes as manure, energy crops. During AD, i.e. organic materials are decomposed by anaerobic forming bacteria and fina1ly converted to excellent fertilizer and biogas which is primarily composed of methane(CH4) and carbon dioxide(CO2) with smaller amounts of hydrogen sulfide(H2S) and ammonia(NH3), trace gases such as hydrogen(H2), nitrogen(N2), carbon monoxide(CO), oxygen(O2) and contain dust particles and siloxanes. The production and utilisation of biogas has several environmental advantages such as i)a renewable energy source, ii)reduction the release of methane to the atomsphere, iii)use as a substitute for fossil fuels. In utilisation of biogas, most of biogas produced from small scale plant e.g. farm-scale AD plant are used to provide as energy source for cooking and lighting, in most of the industrialised countries for energy recovery, environmental and safety reasons are used in combined heat and power(CHP) engines or as a supplement to natural. In particular, biogas to use as vehicle fuel or for grid injection there different biogas treatment steps are necessary, it is important to have a high energy content in biogas with biogas purification and upgrading. The energy content of biogas is in direct proportion to the methane content and by removing trace gases and carbon dioxide in the purification and upgrading process the energy content of biogas in increased. The process of purification and upgrading biogas generates new possibilities for its use since it can then replace natural gas, which is used extensively in many countries, However, those technologies add to the costs of biogas production. It is important to have an optimized purification and upgrading process in terms of low energy consumption and high efficiency giving high methane content in the upgraded gas. A number of technologies for purification and upgrading of biogas have been developed to use as a vehicle fuel or grid injection during the passed twenty years, and several technologies exist today and they are continually being improved. The biomethane which is produced from the purification and the upgrading process of biogas has gained increased attention due to rising oil and natural gas prices and increasing targets for renewable fuel quotes in many countries. New plants are continually being built and the number of biomethane plants was around 100 in 2009.