• Journal of Korean Society of Environmental Engineers
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• v.27 no.1
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• pp.93-100
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• 2005

Comparative thickening and dewatering characteristics of municipal wastewater sludge were investigated in terms of separated and combined treatment of primary and secondary BNR sludge. Also, various conditioning methods such as cation polymer addition, steam and ultrasonication treatment were examined to improve dewaterability of sludge. The dewaterability was measured by using specific resistant test, wedge zone simulator and centrifuge. The result of the sludge thickening test revealed that separated thickening was better in terms of solids recovery and supernatant quality. Particularly, the thickening of primary sludge with high solids (about 3.5% TS) showed very poor solid separation. The addition of cation polymer showed better conditioning characteristic for dewatering and the optimal polymer dosage was 0.26% for primary sludge, 0.43% for secondary sludge and 0.38% for combined sludge. Contrary to the result of the thickening, the dewatering test revealed that dewatering of the combined sludge is better than that of separated sludge, representing better solids separation and filtrate quality. The polymer addition was essential to improve dewaterability in filter (belt) press type dewatering but it was inefficient for the dewatering of secondary sludge only. The centrifuge type dewatering showed better performance and the dewaterability was slightly improved when the polymer was added. Based on the results of this research a sustainable sludge treatment process, particularly in terms of the recycle water quality and solids recovery, was proposed.

• Resources Recycling
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• v.13 no.3
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• pp.12-18
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• 2004

A study on the enhancement of the dewaterability of sewage sludge was carried out by using the sea waste materials as a dewatering aid. It was made from a starfish and a shell by heating at $105∼700 ^{\circ}C$ and centrifuge and belt press were used as a mechanical dewatering process. The moisture content of sludge cake was reduced by 15∼22% (w/w) after addition of the dewatering aid at the dose of 1∼8 g/100mL of digested sludge. CST (capillary suction time) was measured to evaluate the effect of dewatering aid on sludge dewatering properties. CST was reduced after addition of a shell while increased after addition of a starfish. Enhancement of dewaterability after addition of a shell was better than that of a starfish. The heating temperature effect of the dewatering aid on dewaterability was not clear.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1999.10a
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• pp.196-197
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• 1999

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.04a
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• pp.47-47
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• 2000

초지기의 생산성을 극대화 하기 위한 방법은 초지기의 고속화와 광폭화를 통한 대형화이다. 다품종 소량 생산에서는생산 설비의 대형화가 비효율적이기 때문에 고속 광폭화는 주로 신문용지의 생산에 적용되어 왔다. 그러나 현재 인쇄용지 분야에 있어서도 생산성 향상의 일환으로 고속 초지기들이 도입되고 있으며, 2000m/min에 도달하기 위한 노력이 진행 중이다. 장망식 초지기에서는 와이어의 하부로만 탈수가 일어나기 때문에 제조된 종이는 표면과 이면의 구조적 차이가 발생한다.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2002.05a
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• pp.56-56
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• 2002

제지산업의 발전에 따라 치환도가 다른 여러 가지 용도의 양성 전분이 개발되어 적 용되고 있다. 특히 보류제로서 양성전분을 사용할 경우 보류 향상과 더불어 강도개선 효과를 동시에 얻을 수 있는 이점을 지니고 었다. 하지만 용수 조건의 악화, 미세분 함 량의 증가 등과 같은 점차 열악해지는 초지공정에 적용하기 위해서는 보다 높은 치환 도의 전분이 요구 되고 있다. 이에 본 연구에서는 고치환 양성 전분이 초지계 내에 첨가되었올 경우 나타나는 홉 착 특성을 파악하고, 보류 및 탈수 성능을 평가함으로서 올바른 적용 방법을 제시하고 적용 효율의 극대화를 모색하고자 하였다. 산-염기 세척과정을 거쳐 제조한 활엽수 BKP를 이용해 지료를 조성하고, DDA

• The KSFM Journal of Fluid Machinery
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• v.7 no.2 s.23
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• pp.35-40
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• 2004

A generation rate of sludge in Korea had increased dramatically about $200\%$ for a decade. A requirement for high efficiency dewatering system being possible to produce the low water content cake have suggested due to the appearance of commercial and social problems about handling of dewatered cake. The conventional dewatering system with mechanical compression device was not suitable to produce the low water content cake and didn't cope with lots of requirements. Therefore, this paper was to develop the high efficient filter press with the compressive and heating forces through the heating plate to be built between membrane fillet plates. It is possible to produce the low water content cake and improve the dewatering rate, so this equipment positively coped with several types of problems related to the sludge dewatering. The plate heated by heat transfer materials such as steam, hot water and thermo-oil made the sludge make the residual moisture within the cake to discharge easily and to improve the dewatering efficiency of equipment. The pilot scale experiment with 500kg of cake production showed that the dewatering efficiency determined by the final water content and dewatering velocity was improved $30\%$ more than the conventional dewatering equipment.

• 유체기계공업학회:학술대회논문집
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• 2003.12a
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• pp.278-283
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• 2003

A generation rate of sludge in Korea had increased dramatically about 200 % for a decade. A requirement for high efficiency dewatering system being possible to produce the low water content cake have suggested due to the appearanceof commercial and social problems about handling of dewatered cake. The conventional dewatering system with mechanical compression device was not suitable to produce the low water content cake and didn'tcope with lots of requirements. Therefore, this paper was to develop the high efficient filter press with the compressive and heating forces through the heating plate to be built between membrane filter plates. It is possible to produce the low water content cake and improve the dewatering rate, so this equipment positively coped with several types of problems related to the sludge dewatering. The plate heated by heat transfer materials such as steam, hot water and thermo-oil made the sludge make the residual moisture within the cake to discharge easilyand to improve the dewatering efficiency of equipment. The pilot scale experiment with 500kg of cake production showed that the dewatering efficiency determined by the final water content and dewatering velocity was improved 30% more than the conventional dewatering equipment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.4
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• pp.874-880
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• 2007

Capillary Suction Time(CST) and Specific Resistance to Filtration(SRF) were commonly used to evaluate the sludge dewatering behaviors. A coupled equation was developed through the mathematical theory which represented both CST and SRF as the physical filterability of the ultrasonically treated sludge. The model for coupling CST and SRF includes both equipment variables and variables related to sludge characteristics, and verified with the results from experiments. The results of the theoretical and experimental study showed that a good correlation relationship among dewaterability indices.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.1
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• pp.1-6
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• 2015

The purpose of this study is to suggest the effective operation method by developing prediction model for the gas production rate, an indicator of the effectiveness of anaerobic digestion tank, using data mining. At the result, gas production estimate model is developed by using ANN within 10% error. It is expected to help operation of anaerobic digestion by suggesting selected parameter. Meanwhile case based reasoning is applied to develop dewatering cake management technology. Case based reasoning uses the most similar examples of past when a new problem occurs, therefore in this study, management measures are developed that proposes dewatering cake minimization with the minimum change by applying the case based reasoning to sludge disposal process.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2005.06a
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• pp.43-69
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• 2005