• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.95-96
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• 2006

Stainless steel sludge is generated as a waste in the grinding process, and the possibility of recycling stainless steel is considered here. In this study, we considered the possibility of using the stainless steel sludge as metal powder for MIM or raw material for metal foam. For the MIM process, the metal powder will need some improvement, and flotation and spheroidizing processes of the sludge are necessary. For fabrication of the metal foam, untreated sludge can be used, and steel foam about 90% porosity is produced.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.77-80
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• 2004

In this paper, we have investigated the characteristics of the magnetic abrasive using sludge on polishing of internal finishing of seamless stainless steel (STS304) tube applying magnetic abrasive polishing. Either white alumina (WA) or green carborundum (GC) grain was used to resin sludge at a low temperature, and the sludge of magnetic abrasive powder was synthesized and crushed into 200 meshes. Surface roughness was measured before and after polishing, and more than 40% of improvement of surface roughness was achieved when WA grain was used under a specific condition. Even though some degree of surface roughness due to deeper scratches still exist, but the result showed a prospective magnetic abrasive polishing using sludge with WA or GC grains.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.432-436
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• 2001

In this study, calcium sulfate(gypsum) powder was obtained using waste sulfuric acid and stainless refinery sludge by- produced from chemical reagent and the iron industry, by the neutralization of waste sulfuric acid. As variables for the experiment the mole ratio of the H$_2$SO$_4$ : Ca(OH)$_2$, the pH, the reaction temperature and time, the amount of catalyst were used. The crystal shape and microstructure of obtained powder were observed by XRD and SEM, and the thermal property was investigated by DTA. As the NaCl is added 0~20wt% as a catalyst to the H$_2$SO$_4$ : Ca(OH)$_2$, system it can be found that the crystal shape goes through the processes as follows : gypsum dihydratlongrightarrowgypsum hemihydrate＋gypsum dihydratelongrightarrowgypsum hemihydrate. And gypsum hemihydrate is $\beta$-type as the result of DTA. As waste sulfuric acid and stainless refinery sludge were used, the pH of reacted solution (which was 0.8) was rapidly raised up to 8~9 by the addition of stainless sludge and gypsum dihydrate was produced as a by-product. Therefore, it was found that stainless refinery sludge is sufficiently applicable for the neutralization of waste sulfuric acid.

• 동굴
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• 제78호
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• pp.23-27
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• 2007

In this paper, we have investigated the characteristics of the magnetic abrasive using sludge on polishing of internal finishing of seamless stainless steel tube applying magnetic abrasive polishing. Either white alumina grain was used to resin sludge at a low temperature, and the sludge of magnetic abrasive powder was synthesized and crushed into 200 meshes. Surface roughness was measured before and after polishing, and more than 40% of improvement of surface roughness was achieved when grain was used under a specific condition. Even though some degree of surface roughness due to deeper scratches still exist, but the result showed a prospective magnetic abrasive polishing using sludge with white alumina grains.

• 한국자동차공학회논문집
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• 제12권6호
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• pp.151-157
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• 2004

In this paper deals with behavior of the magnetic abrasive using sludge on polishing characteristics in a new internal finishing of seamless stainless steel tube applying magnetic abrasive polishing. The magnetic abrasive using sludge-abrasive grain WA and GC used to resin bond fabricated low temperature. And sludge of magnetic abrasive powder fabricated that sludge was crused into 200 mesh. The previous research have made an experiment in the static state the movement of magnetic abrasive grain is nevertheless in the dynamic state. In this paper, We could have investigated into the changes of the movement of magnetic abrasive grain. In reference to this result, we could have made the experiment which is set under the condition of the magnetic flux density, polishing velocity according to the form of magnetic brush.

• 동굴
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• 제82호
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• pp.8-12
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• 2007

In this paper, we have investigated the characteristics of the magnetic abrasive using sludge on polishing of internal finishing of seamless stainless steel tube applying magnetic abrasive polishing. Either green carborundum(GC) grain was used to resin sludge at a low temperature, and the sludge of magnetic abrasive powder was synthesized and crushed into 200 meshes. Surface roughness was measured before and after polishing, and more than 38% of improvement of surface roughness was achieved when grain was used under a specific condition. Even though some degree of surface roughness due to deeper scratches still exist, but the result showed a prospective magnetic abrasive polishing using sludge with green carborundum grains.

• 한국표면공학회지
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• 제42권1호
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• pp.53-57
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• 2009

Recovery of heavy-metallic component from a waste solution of factory was undertaken by the solar cell electricity. The solution was obtained from an electrolytic etching process of 316L stainless steel. The electrolysis of the solution for recovery of heavy metallic components was made with platinum plated titanium mesh anode and copper plate cathode. Analysis for the solution and electro-winned materials were made by EDS, XRD and SEM. Iron, chromium, and sulfur components were recovered on the cathode from the solution. Result of EDS analysis for the electro-winned materials revealed that some metal oxide were contained in the recovered material. The recovered materials were expected to have metallic form only by the electrolysis, but metal compounds were contained because of weak solar cell power. Nickel and manganese component in the solution doesn't recovered by this electrolysis process, but they made a sludge with phosphoric acid in the solution.

• Transactions on Electrical and Electronic Materials
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• 제6권3호
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• pp.128-132
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• 2005

In this paper, we have investigated the characteristics of the magnetic abrasive using sludge on polishing of internal finishing of seamless stainless steel (STS304) tube applying magnetic abrasive polishing. Either white alumina (WA) or green carborundum (GC) grain was used to resin sludge at a low temperature, and the sludge of magnetic abrasive powder was synthesized and crushed into 200 meshes. Surface roughness was measured before and after polishing, and more than $40\%$ of improvement of surface roughness was achieved when WA grain was used under a specific condition. Even though some degree of surface roughness due to deeper scratches still exist, but the result showed a prospective magnetic abrasive polishing using sludge with WA or GC grains.

• 자원리싸이클링
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• 제1권1호
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• pp.23-28
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• 1992

용매추출법을 이용하여 스텐레스 산세폐액으로부터 산과 니켈 및 크롬 등의 유가금속을 효과적으로 회수하기 위한 처리공정을 개발하고자 하였다. 현재까지 일본, 스웨덴 및 캐나다 등에서 이와같은 폐산을 처리하기 위한 몇가지 기술이 개발된 바 있으나 이들 방법은 대부분 산의 회수만을 주목적으로 한 것이기 때문에 폐산에 함유된 금속성분이 수산화물 스러지로 그대로 폐기되는 결점을 지니고 있다. 본 실험은 질산 및 불산과 함께 금속성분인 니켈과 크롬을 회수하여 정제산을 산세공정에 재상용하는 한편 처리과정에서 발생하는 스러지양을 최소한으로 줄이고자 하는 목적에서 시도되었다. 질산과 불산의 혼산은 TBP를 추출재로 사용한 용매추출에 의해 효과적으로 회수할 수 있었으며 여기에서 나온 폐액은 중화침전에 의해 철분을 제거한 다음 최종적으로 D2EHPA를 추출제로 사용하여 니켈과 크롬을 분리회수 할수 있었다.

• Korean Chemical Engineering Research
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• 제50권2호
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• pp.211-216
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• 2012

염화제이철 수용액에 의한 스테인레스 강판의 식각반응에 관한 연구를 수행하였다. 식각액 교반속도, 식각온도, $Fe^{3+}$ 이온 농도, 식각액의 유리산도 및 비중 등 여러 공정변수가 식각속도에 미치는 영향에 대해 조사하였고, 그 결과, AK(aluminum-killed) 철, 크롬(chlomium) 강, 그리고 스테인레스 강(STS430J1L 합금)의 식각반응이 1차 반응식을 잘 따름을 알 수 있었다. 또한 식각액의 피로도(fatigue ratio)가 16% 이하로 유지되면 식각액 내에 슬러지가 발생하지 않으며, 식각된 강판의 표면거칠기 또한 좋아짐을 알 수 있었다. 본 연구에서 조사한 범위 내에서는, 식각액의 보메(Baume)가 증가하면 식각속도는 감소하나 유리산도가 식각속도에 미치는 영향은 미비함을 알 수 있었다. 한편 본 연구의 실험결과는 공정모델링을 통해 유도된 식각속도식의 계산결과와 잘 일치함을 알 수 있었다.