• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제2권1호
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• pp.9-19
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• 1998

A laboratory study was conducted to investigate the immobilization of the laboratory waste sludge, mainly from chemical oxygen demand (COD) waste, using cementitious binders. The binders were: Ordinary Portland Cement (OPC), and lime-Rice Husk Ash(RHA) cement. The economic evaluation was done for three different kinds of cementitious binders, namely, OPC, Portalnd Rice Husk Ash Cement (PRHAC) which contained rice husk ash 50 percent by dry weight, and lime-RHA cement. The result showed that lime-RHA cement was the cheapest. The applicability of Freundlich's desorption isotherm was studied to assess the teachability of sludges. The teachability of cement mortars was found to follow the desorption isotherms. Therefore, it was concluded that based on this test, the leachate concentrations of the solidified heavy metals could be predicted, approximately by the Freundlich's isotherm desorption modeling.

• 한국환경과학회지
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• 제2권1호
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• pp.9.2-19
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• 1993

A laboratory study was conducted to investigate the immobilization of the laboratory waste sludge, mainly from chemical oxygen demand (COD) waste, using cementitious binders. The binders were: Ordinary Portland Cement (OPC), and lime-Rice Husk Ash (RHA) cement. The economic evaluation was done for three different kinds of cementitious binders, namely, OPC, Portaind Rice Husk Ash Cement (PRHAC) which contained rice husk ash U percent by dry weight, and lime-RHA cement. The result showed that lime-RHA cement was the cheapest. The applicability of Freundlich's desorption isotherm was studied to assess the teachability of sludges. The teachability of cement mortars was found to follow the desorption isotherms. Therefore, it was concluded that based on this test, the leachate concentrations of the solidified heavy metals could be predicted, approximately by the Freundlich's isotherm desorption modeling.

• Advances in concrete construction
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• 제7권2호
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• pp.75-85
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• 2019

The present study is focused on the mechanical and durability properties of ternary blended cement concrete mix of different grades 30 MPa, 50 MPa and 70 MPa. Three mineral admixtures (fly ash, silica fume and lime sludge) were used as a partial replacement of cement in the preparation of blended concrete mix. The durability of ternary blended cement concrete mix was studied by exposing it to acids HCl and $H_2SO_4$ at 5% concentration. Acid mass loss factors (AMLF), acid strength loss factor (ASLF) and acid durability factor (ADF) were determined, and the results were compared with the control mix. Chloride ions penetration was investigated by conducting rapid chlorination penetration test and accelerated corrosion penetration test on control mix and ternary blended cement concrete. From the results, it was evident that the usage of these mineral admixtures is having a beneficiary role on the strength as well as durability properties. The results inferred that the utilization of these materials as a partial replacement of cement have significantly enhanced the compressive strength of blended concrete mix in 30 MPa, 50 MPa and 70 MPa by 42.95%, 32.48% and 22.79%. The blended concrete mix shown greater resistance to acid attack compared to control mix concrete. Chloride ion ingress of the blended cement concrete mix was low compared to control mix implying the beneficiary role of mineral admixtures.

• 한국환경농학회지
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• 제22권2호
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• pp.87-93
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• 2003

하수오니의 농경지 유입에 따른 작물의 생육상황, 피해증상 및 부위별 무기성분 함량에 미치는 석회의 개량 효과를 검토하고, 토양 및 식물체중의 화학성분이 식물생육에 미치는 영향을 살펴보기 위하여 공단하수오니 및 석회를 조합 처리하고 3요소구를 대조구로 하여 열무의 생육상과 화학성분 함량을 분석 비교하였다. 시험 후 토양의 화학성은 하수오니구가 3요소구와 비교하여 EC, T-N 및 미량성분 함량은 높았고, Av, $P_2O_5$ 및 치환성 양이온은 낮게 나타났다. 하수오니 시용구에서 열무의 피해증상으로 잎의 황백화 현상을 보였으나 석회처리구에서는 생육이 양호하였고 황백화 현상도 나타나지 않았다. 하수오니 시용구에서 석회의 개량효과로 열무 생육과 수량감소를 경감시키는 효과가 나타났으며, 특히 하수오니 50 Mg/ha 구에서는 무처리에 비해 잎과 뿌리의 수량이 각각 29%, 48% 증수되었다. 하수오니 시용구에서 3요소구와 비교하여 열무증의 유효성분인 P, K, Ca 및 Mg 함량이 낮았으나 석회처리로 열무에 흡수된 유효성분 함량이 높아지는 경향을 보였다. 토양 및 열무 엽중의 Cu, Zn, Ni 함량을 열무 잎의 T-N과는 정의 상관, P 및 양이온과는 부의 상관을 보였다. 열무중의 Cu, Zn, Ni함량은 잎과 뿌리 모두에서 열무 생체수량과 고도의 부의 상관을 보였다. 2차 회귀식에 의해 계산된 열무 엽중의 Cu, Zn에 대한 5% 수량감소 농도는 각각 22.4, 349 mg/kg이었다.

• 한국농공학회지
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• 제39권5호
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• pp.64-70
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• 1997

Sludge is generated in the process of water and wastewater treatment, and it has been causing various problems environmentally and economically. The firing technology in pottery industry was applied to the sludge treatment, and the final product was called artificial soil. For the production of artificial soil, lime and chabazite was used as additive, and the mixed material was thermally treated in the firing kiln at $300^{\circ}$ temperature for about 15 minutes. The physico-chemical characteristics of the artificial soil was analyzed and it showed that the artificial soil could be used as a soil conditioner for farmland. The concentrations of the toxic heavy metals in the artificial soil were lower than those in the soil quality standard for farmland. It was high in permeability, total nitrogen and total phosphorous concentrations and surface area of the artificial soil compared to the common field soil. Preliminary cost analysis showed that the sludge treatment cost for artificial soil was less than the disposal cost in the current landfill disposal method. This study illustrated that the artificial soil production process can be a feasible alternative for sludge treatment, and produced artificial soil may he applied to farmland without causing significant adverse effect. Further study is recommended for practical application of the system and verification of the longterm effect of the artificial soil on farmland.

• 동력기계공학회지
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• 제18권3호
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• pp.93-99
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• 2014

The purpose of this paper is to manufacture the non-sintered ceramic used lime and industrial waste. The used materials were basalt powder sludge, calcium hydroxide(Ca(OH)2) and additives such as calcium stearate and $TiO_2$. The mixing ratios between Ca(OH)2 and sludge were 5:5, 6:4 and 8:2, respectively. The ceramic forms were pressured by 100, 200 and 300 bar and cured in 14% CO2 for 12 days. The behaviors of compressive strength, specific gravity, water absorption and pH of ceramic form were investigated. The results were compressive strength of over 36 MPa, water absorption of over 8.8%, pH value of over 12.3. And these results satisfied GR F 4006 and 4031 standard.

• 자원리싸이클링
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• 제3권3호
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• pp.12-20
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• 1994

제철공정에서 발생하는 각종 분진 및 Sludge류는 미세한 입도와 Zn, Alkali의 높은 농도 때문에 소절공정에의 직접활용이 곤란하다. 이러한 성분 및 입도상의 문제를 극복하기 위하여 이들 폐기물로부터 새로운 Flux를 개발하여 철광석 소결공정에 적용하였다. 소결 Dust와 석회석 Sludge를 혼합 예비소성하여 얻은 Calcium ferrite를 새로운 Flux로써 철광석의 소결에 적용한 결과 소결 생산성을 향상시키고 소결광의 상온강도를 개선하는 효과를 얻을 수 있었다.

• 한국토양비료학회지
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• 제45권6호
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• pp.961-967
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• 2012

본 연구에서는 6 종류의 안정화제의 중금속 안정화 효율을 평가하기 위해 생물학적 평가 방법을 이용하였다. 12 종의 식물을 대상으로 한 스크린 실험에서 청경채를 선발하여 이를 안정화제 평가에 사용하였다. 식물 독성실험 결과 농용석회와 제강슬래그는 청경채의 뿌리 신장에, 백운석은 지상부 신장에 각각 악영향을 주었다. 화학적 평가 방법뿐만 아니라 생물학적 평가 방법을 고려하였을 때에는 AMD 슬러지가 가장 추천되어질 만한 것으로 판단된다. 그러나 토양 환경과 청경채의 특수성 때문에 위 결과를 일반화 하는 것은 어려우며 명확한 결과 도출을 위해서 재배기간의 조정과 추가적인 화학 침출 평가 방법 등이 필요해 보인다.

• 한국환경농학회지
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• 제21권1호
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• pp.38-44
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• 2002

공단 하수오니의 농경지 유입에 따른 토양의 중금속 함량과 작물체로의 중금속 흡수이행에 미치는 석회시용 효과를 조사하였다. 공단하수오니 및 돈분퇴비를 각각 25, 50 Mg/ha 시용토양에 석회를 3 Mg/ha 처리하여 알타리무를 재배 수확한 후 토양과 작물체 중의 중금속 함량을 분석하였다. 시험후 토양의 중금속 함량은 공단하수오니구에서 대조구 (NPK 처리구) 및 돈분퇴비구보다 높았으며, 특히 공단하수오니 50 Mg/ha 시용구에서는 구리, 아연, 니켈 및 크롬함량이 대조구와 비교하여 12$\sim$48배 높은 농도를 보였다. 공단하수오니 시용으로 알타리무로 흡수 이행된 구리, 아연 및 니켈 함량은 증가하여 알타리무 엽중의 농도가 식물독성 피해농도를 초과하는 수준이였다. 공단하수오니 시용토양에서 석회시용으로 알타리무 엽과 뿌리중 구리, 아연 및 니켈 함량은 크게 경감되었으며, 시험후 토양의 pH와 알타리무중 구리, 아연 및 니켈 함량과는 고도의 부의 상관을 보였다 이상의 결과에서 석회시용이 중금속이 다량 함유된 하수오니 유입으로 인한 작물의 독성피해와 중금속 흡수 이행성을 경감시킬 수 있는 일시적인 개량방법으로 이용될 수 있을 것으로 생각되었다.

• 한국농공학회지
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• 제40권2호
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• pp.102-111
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• 1998

Large amount of sludge have been generating in the process of water and wastewater treatment in urban area, and it has been making many environmental problems. Currently almost of sludge is landfilled, and since sludge is difficult to handle and dehydrate, the permeated water from the filled-in ground contaminate the surrounding soil and groundwater which may cause serious environmental and sociological problems. The organic component in sludge can be almost removed through the heat treatment process, and the final product is called artificial soil or artificial media according to the temperature control. To produce artificial media using sludge, chabazite and lime were used as an additive, and the mixture of sludge & additives was thermally treated in the firing kiln at about 800~1, 100。C for about fifteen minutes. The physical and chemical characteristics of the produced artificial media were analyzed, and it showed that it can be used as an artificial media for plant production or soil conditioner for farmland. The concentrations of the toxic heavy metals in the artificial media were lower than the soil quality standard for farmland. The characteristics of produced artificial media, using the mixture of sludge and additives through the heat treatment, is similar to the natural chabazite and soil. The analyzed result of the mineral composition of artificial media showed that it has a characteristics similar to natural stable soil, so the produced artificial media may be applied to farmland or water culture without causing adverse effect. Therefore this study showed that the above process can be a feasible alternative for sludge treatment.