residue as the raw material. As one of the preconceived raw material to produce high-quality coal-based carbon material, the changes of structure of CLP during liquid-phase carbonization process have been detailed investigated in this study. Actually, FTIR and curve-fitted method were used to quantitative analyze the aromaticity index (Iar), the ratio of CH3/ CH2, and basic functional groups (C=C, C=O, and C–O) of CLP and its liquid-phase carbonization products. Polarizing microscope, XRD and curve-fitted methods were used to characterize the microstructures of CLP and derived products. The results show that, branched chain and C=O group are the active reaction point in liquid-phase carbonization process. What’s more, 450 °C is a critical temperature point on the severe thermal polycondensation of CLP. The XRD and curve-fitted analysis of CLP and its liquid-phase carbonization products shows that, the stacking height (Lc), parallel layers (N), and the numbers of aromatic ring in each layer (n) are gradually larger with the improve of liquid-phase carbonization temperature.
본 연구는 여러 해조류 소재 중에서 국내 생산량이 많고 연소가 뛰어나 수율이 높은 해초액 화합물을 대량생산 실용화가 가능한 것을 목표로 하며, 해조류인 미역 다시마 톳 기타 김 등을 이용하는 것으로서 주로 원료확보는 폐자원 해조류 등을 이용하여 고온에서 Poly step trap식 건류 공정 적용인 탄화공정을 수반함으로서 생성된 해초 액을 개발하는 연구다. 이를 분리 정제하는 기술적 공정을 개발하고 나아가 시제품을 개발하여 농업, 식품, 비료, 의약품 대체화를 추진함과 동시에 제일 문제시 되고 있는 식품 첨가제를 해결함으로서 고 부가치성 창출과 바이오 생물약제 원료로 개발하고자 하였다. 그래서 해초 액을 추출 분리 및 정제연구를 실시하여 화합물 분석실험을 추진하였다. 그리고 목초액과 성분비교 우위성 입증실험을 성분비교실험을 통해서 비교 검증실험을 추진하였다.
4D carbon fiber preforms were manufactured by weaving method and their carbon fiber volume fractions were 50% and 60%. In order to form carbon matrix on the preform, coal tar pitch was used for matrix precursor and high density carbon/carbon composites were obtained by high densification process. In this process, manufacture of high density composites was more effective according to pressure increasement. When densificating the preform of 60% fiber volume fraction with 900 bar, density of the composites reached at 1.90 g/cm3 after three times processing. Degree of pressure in the densification process controls macro pore but it can not affect micro pore. During the carbonization process, micro pore of the preform were filled fully by once or twice densification processing. But micro pore were not filled easily in the repeating process. Therefore, over three times densification processing is the filling micro pore.
석탄계 핏치의 열처리 온도 및 압력에 따른 결정화도와 기공도 그리고 산화저항성 등을 관찰하였으며, hexagonal type 4D 탄소/탄소 복합재를 석탄계 핏치로 가압함침 및 탄화시킨 다음 가해준 압력이 고밀도화에 미치는 영향을 관찰하였다. 석탄계 핏치의 가압탄화 압력이 흑연화도에 크게 영향을 미치지 않았으며, 기공면적비에 있어서는 압력을 600bar로 상승시켜 줌으로써 상압 처리한 경우 보다 1.5배 정도 감소 하였다. 650˚C까지 열처리하여 얻은 코우크스의 산화반응 개시온도는 처리압력이 증가함에 따라서 지연되었다. 탄소/탄소 복합재의 함침압력을 100bar에서 600bar로 상승시켜 줄 경우 밀도 증가율이 크게 향상 되었으며 기공도는 감소하였다.
본 연구에서는 2D-woven fabric에 결합재로 페놀수지를 사용하여 성형한 CFRP의 탄화거동을 관찰하였다. TMA분석 결과 적층 두께방향에서는 365-370˚C 법선방향에서는 118-128˚C 에서 치수변화가 일어났다. 각 온도 구간별로 광학현미경으로 관찰한 결과 CFRP제조시 형성된 크랙이나 기공은 열처리온도에 따라 성장하였으며, 400-500˚C 부근에서 새로운 많은 크랙이 형성되었다. 기공률과 밀도가 400-500˚C 에서 급격히 변화한 것을 볼 때 이 구간에서 복합재 내부에서 크랙이 형성 및 성장하는 것을 알 수 있었다. 따라서 CFRP를 탄화할 때 승온속도를 구간별로 조절할 필요성이 있는 것으로 판단되었다.
Using a mixture of sewage sludge and woody waste, optimal conditions for the bio-briquette process of carbonization residue were evaluated by compressive strength and bulk density. For the bio-briquette process, the optimal conditions were determined to be a molding temperature of 110oC and a moisture content of 10%. As the lignin in the carbonization residue can be used as a natural binder because of its plasticizing property, the bio-briquette process uses this property. To increase the compressive strength to >3.50 MPa, binders such as polyvinyl alcohol (PVA), guar gum, and starch were mixed in the carbonization residue. At 3 wt.% of PVA, 3 wt.% of guar gum, and 5 wt.% of starch, the conditions of binder usage were evaluated. To examine the cost in the bio-briquette production with the addition of the binder, the proportion of binder cost for the bio-briquette production were evaluated at 9.2% for PVA, 8.6% for guar gum, and 3.3% for starch, and starch was determined to be the best binder for the bio-briquette process.
Since sewage sludge has low heating value as an energy source, it is desirable that sewage sludge is mixed with woody waste to enhance energy potential. Among thermal methods for waste to energy, carbonization process is used in this study. In order to estimate reaction kinetics for carbonization process using mixture of woody waste and sewage sludge, the content of sewage sludge is varied from 10 ~ 30% in mixture of woody waste and sewage sludge in carbonization process. Carbonization time is changed from 10 min to 50 min and carbonization temperature is varied from 250oC to 350oC. The carbonization process for mixture of woody waste and sewage sludge was optimized at carbonization temperature of 300oC for 20 min, 20% of sewage sludge content. As increased carbonization temperature, reaction rate constant, frequency factor and degree of carbonization were increased. As increased the content of sewage sludge, conversion, ash content and degree of carbonization were decreased. At optimal conditions for carbonization process, frequency factor and activation energy in Arrhenius equation can be decided by 3.61 × 10−2 min−1, 7,101.8 kcal/kmol respectively.
Carbonization using chicken manure was used to obtain an energy source. In order to estimate the reaction rate at theoptimal conditions for chicken manure in carbonization process it is estimated the reaction kinetics for the process. Thecarbonization process for chicken manure was optimized at carbonization temperature 300oC to 400oC in 20minutes. Fromthe examination of conversion characteristics of chicken manure, carbonization reaction can be described by the 1st orderkinetic reaction. Frequency factor(A) of reaction rate for chicken manure was evaluated to be 0.55×10−2min−1 and theactivation energy was estimated to be 3,815.0kcal/kmol. As increased carbonization temperature from 250oC to 400oC,reaction rate constant of chicken in the 1st order kinetic reaction is also increased from 0.0604min−1 to 0.1383min−1.In this study, carbonization degree of chicken manure in carbonization process was estimated by kinetic reaction deduction.The result of kinetic reaction in carbonization of chicken manure was evaluated to be 1st order kinetic reaction.
Hydrothermal carbonization (HTC) is a highly effective technique for treating lignocellulosic biomass and organic waste of various shapes and moisture content. The solid product of HTC is friable, hydrophobic, and increased in mass and energy densification compared to the raw biomass. also solid product is similar regardless of the type of biomass used. A liquid solution of five carbon and six carbon sugars, along with various organic acids and 5-HMF, is also produced from HTC of lignocellulosic biomass. The gaseous phase product consists mostly of CO2. Solid product has the similar characteristics to low rank coal. The solid fuel characteristics of feedstock was increased with reaction temperature and time via HTC process. However, mass yield was decreased with increasing temperature and time. Therefore, it is necessary to optimize the reaction temperature and time for HTC. The HTC process produces the solid product and a large amount of water. Thus the reuse or treatment techniques of liquid product is necessary. Therefore, potential of biological treatment of HTC liquid product was evaluated.
Carbonization process with pig manure is carried out to estimate the reaction kinetics with increasing carbonizationtime and temperature in the process. From the examination of conversion characteristics of pig manure, carbonizationreaction can be described by the 1st order kinetic reaction. Degree of carbonization, which can be expressed by C/H moleratio, is increased with increasing carbonization temperature. As increased carbonization temperature from 250oC to 400oC,reaction rate constant in the 1st order kinetic reaction is also increased from 0.0622min−1 to 0.1999min−1. Frequency factorand activation energy in Arrhenius equation for pig manure in the carbonization process can be decided by 1.06×10−3min−1 and 5441.8kcal/kmole, respectively. From the results of the reaction kinetics including TGA and SEM analysis,it is desirable that pig manure should be carbonized below carbonization temperature 400oC.