• 한국물환경학회지
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• 제31권6호
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• pp.625-631
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• 2015

In this study, low cost bio-flocculants, chitosan, cationic starch and Mg-sericite, were used as a flocculant to harvest freshwater microalgae, Chlorella vulgaris. Chitosan, cationic starch and Mg-sericite separated successfully >98% of C. vulgaris at following optimal parameters: 90 mg/L chitosan at pH 6-7, 70 mg/L cationic starch at pH 9-10 and 50 mg/L Mg-sericite at pH 4-5. A relatively high correlation coefficient (R²) of 0.9993 for chitosan, 0.9971 for catonic starch and 0.9924 for Mg-sericite was obtained. The investigated flocculants amount increased linearly with increasing the microalgae amount. The biopolymer, Mg-sericite, was more effective than that of other investigated flocculants. These results indicated that a bio-flocculants, chitosan, cationic starch and Mg-sericite, could prove to be an effective flocculant for economical production of microalgae biomass. In addition, Mg-sericite was more effective comparing to the other investigated flocculants.

• 한국환경과학회지
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• 제30권2호
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• pp.135-143
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• 2021

This study executed evaluation of drying characteristics based on the polymer injection rate (8%, 10% and 12%) and the drying method[NIF(near-infrared ray). According to this study analyzed VS, VS/TS, and calorific value compared with 'the auxiliary fuel standard of the thermoelectric power plant and the combined heat & power plant'. The results are as follows. In the case of NIR, the VS was slightly changed at the early stage of the material preheating period and the constant drying rate period with low moisture evaporation. But VS reduction was shown higher as moisture was dried. In the case of non-digested sludge with high VS content, the VS reduction rate by drying was shown lower than that of digested sludge. As the flocculant injection rate increased, the VS loss due th drying was found to be small. Also, the higher the flocculant injection rate was the longer the drying time. Especially, in the case of the NIR drying equipment, as the moisture content of sewage sludge decreased(moisture content 20~40%), the loss of net VS also showed a tendency to increase sharply. It is shown that the high calorific value according to the drying time of the non-digested sludge was changed from 590 kcaℓ/kg to 3,005 kcaℓ/kg and from 539 kcaℓ/kg to 2,796 kcaℓ/kg.

• Applied Biological Chemistry
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• 제41권6호
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• pp.465-470
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• 1998

미생물이 생산하는 유기폐수처리용 생물응집제를 개발하기 위하여 보관균주 및 자연계로부터 100 units/ml 이상의 응집활성을 나타내는 응집제 생산균주를 1차로 분리하고 돈분폐수에서 가장 높은 제거율을 보인 KH-54를 최종 선별하였다. 선별된 균주는 Aeromonas hydrophila로 동정되었으며 응집제 생산을 위한 최적 배양조건은 2.0% mannitol, 0.05% ammonium chloride, 0.02% $KH_2PO_4$, 0.01% $MgSO_4{\cdot}7H_2O$, 0.05% yeast extract 조성의 배지와 초기 pH 7.0, 배양온도 $25^{\circ}C$ 및 교반속도 150 rpm 의 환경인자들이었다. 상기의 조건으로 4일 배양하였을 때 770 units/ml의 응집활성과 81%의 높은 nephelometer turbidity unit(NTU) 제거율을 나타내었으며 이 응집물질은 돈분폐수 이외 두부공업폐수 92%, 제당폐수 78%, 주정공업폐수 68% 및 항생물질 발효공업폐수 36%의 NTU 제거율을 각각 나타내었다.

• 유기물자원화
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• 제15권4호
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• pp.125-130
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• 2007

다양한 환경으로부터 음식물류폐수에 응집특성을 보이는 미생물 6종을 분리하였다. 동정한 결과, 이들은 각각 Bacillus pumilus, Enterobacter sp., Pantotea agglomerans, Bacillus licheniformis, 그리고 두 종류의 Bacillus sp. 균주들로 밝혀졌다. 분리된 미생물중 Enterobacter sp.(YK102), Bacillus sp.(YK103), Pantotea agglomerans (YK104) 등, 3균주의 경우, 대조군으로 사용된 분양균주 Zoogloea ramigera와 비교하여 카올린에 대한 응집율이 모두 8배 이상 높은 것으로 나타났다. 음식물류폐수에 대한 응집실험에서는 Enterobacter sp.(YK102) 균주가 가장 높은 응집능을 보였으며, 대조군으로 사용된 Pseudomonas fluorescens보다 약 2.5배 높은 것으로 나타났다.