• 한국환경과학회지
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• 제11권10호
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• pp.1081-1087
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• 2002

This study was performed to research the characteristics of suspended particulate for Yellow Sand of January, 1999 in Busan. Yellow Sand frequency during 13 years(1988~2000) in Busan showed maximum in April(57%), next to March(21%), May(16%). According to result of 850hPa weather map and backward isentropic trajectory, this event originated from the Gobi Desert and the Loess Plateau of China. And three mode was found in time series of TSP and PM10 concentration, primary peak showed the maximum hourly concentration at ali station. Gamjeondong as industrial site showed the highest TSP concentration and also had the longest high concentration($geq700\mu\textrm{g}/m^3$). In PM10, concentration of primary peak showed maximum value at Yeonsandong, maximum concentration of secondary and third peak was Deokcheondong. Lasted time from primary peak to secondary peak was about 30 hours, between secondary peak and third peak was 18 hours in Busan, The traveling time between occurrence of Yellow Sand the finding of it was 8~9 hours in Busan and 4~5 hours in central area.

• 한국환경과학회지
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• 제25권7호
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• pp.999-1005
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• 2016

The H water treatment plant has been operating since 1982 and has had no renovation. It is assumed that the filters have been operated for more than 30 years and therefore are deteriorated. Many of the filters show an unequal state of air scouring during backwashing. For this study one filter, which was presumed most deteriorated among eighteen filters, was selected as a model filter for renovation. Some of the effects seen after renovation of the underdrain system were a lower average filtrated turbidity by approximately 0.02 NTU and an equal backwash state throughout the filter bed. Sand wash efficiencies by backwash before renovation of the underdrain system were 28%, 8%, and 5% at the surface, 50 cm depth, and 100 cm depth, respectively, and after renovation of the underdrain system were 94%, 26%, and 15%, respectively. The standard deviation of the effective sand size was 0.025-0.033 mm before renovation of the underdrain system and 0.002-0.011 mm after renovation of the underdrain system, meanings there was equal backwash pressure throughout the filter. Filtration time after renovation was approximately 2 times longer than before renovation.

• 환경영향평가
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• 제12권2호
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• pp.99-108
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• 2003

We collected and analyzed PM10 samples to account for the characteristics of heavy metallic elements for yellow sand and non-yellow sand during springtime of 2002 at Busan, The mean PM10 mass concentration for springtime of 2002 was $219.82{\mu}g/m^3$ with the maximum $787.50{\mu}g/m^3$ and the minimum $19.44{\mu}g/m^3$. The mean concentration of metallic elements contained in PM10 are shown as follows : Si>Ca>Fe>Al>Na, respectively. The ratio of mean PM10 mass concentration for yellow sand($362.7{\mu}g/m^3$) to that for non-yellow sand($48.3{\mu}g/m^3$) was 7.5, the significant positive correlation (P<0.05) was found between yellow sand and non-yellow sand. The metallic elements concentration ratios of yellow sand to the non-yellow sand were over 10 times for Al, Ca, Mg, 4~8 times for Fe, Si, Mn. But the concentration of Na, Cu, Zn for non-yellow sand was higher than those of yellow sand. The crustal enrichment factor of Cd, Cu, Pb, Zn, Cr, K, Mn, Na, Ni for yellow sand was higher that of non-yellow sand over 10 times, and concentration rate of soil particles of yellow sand was increased 2.3 times that of nonyellow sand.

• 한국지반공학회논문집
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• 제23권3호
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• pp.123-131
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• 2007

일련의 CID 삼축압축시험과 실내콘관입시험을 통하여 부산모래에서의 상태정수와 정규화된 콘저항치의 상관관계를 파악하였다. 삼축압축시험결과를 토대로 부산모래의 한계상태선을 도출하였으며 3개의 한계상태정수는 $M=1.39(\phi_{cs}=34^{\circ}),\;\Gamma=1.07$ 및 $\lambda=0.068$인 것으로 산출되었다. 부산모래의 상태정수와 정규화된 콘저항치의 상관관계는 $(q_c-p)/p'=27.6\exp(-10.9\Psi)$의 식으로 표현되었으며, 이는 응력이력에 관계없이 동일함을 확인하였다. 문헌조사를 통해 얻은 다른 모래시료의 정규화된 콘저항치 기울기 m 및 $\Psi=0$에서의 절편값 $\kappa$를 비교 분석한 결과, 부산모래는 유사한 $\lambda_{ss}$ 값을 갖는 모래시료 중 가장 큰 $\kappa$값을 보였으나, m과 $\kappa$가 $\lambda_{ss}$와 갖는 관계는 기존에 발표된 자료와 일치함을 확인하였다.

• 한국환경과학회지
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• 제16권10호
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• pp.1157-1167
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• 2007

In an effort to interpret the characteristics of fine particle concentrations in Busan, time variations of hourly monitored concentrations $PM_{10}$ (Particulate Matter with aerodynamic Diameter ${\le}10\;{\mu}m$) in Busan are analyzed for the period from 2000 to 2005. The characteristics of aerosol second generation formation process is also interpreted qualitatively, by using the statistical analysis of the meteorological variables including temperature, wind speed, and relative humidity. The result shows some significant annual, seasonal, weekly and diurnal variations of $PM_{10}$ concentrations. In particular, seasonal(i.e., spring) variations are governed by frequency of yellow sand events even for the non-yellow sand cases where yellow-sand days are eliminated in our analysis. However, in seasonal variation, summer season predominate lower $PM_{10}$ concentrations due to the frequent precipitation, and weekly and diurnal variations are both found to be reflecting the emission rate from traffic amount. Correlation coefficients between $PM_{10}$ concentration and meterological variables for non-yellow sand days show overall negative correlation with visibility, wind speed, cloud amounts, and relative humidity. However for non-precipitation days, during non-yellow sand period positive correlation are found clearly with relative humidity, suggesting the importance of secondary aerosol formation in Busan that can be achieved by both homogeneous aerosol formation and heterogeneous transformations resulting from hygroscopic aerosol characteristics.

• 한국주조공학회지
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• 제22권3호
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• pp.121-129
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• 2002

According to the investigation of waste $CO_2$ molding sand in the 15 steel foundries in Busan and Gyeong area, about 1 ton of waste $CO_2$ molding sand per ton of steel castings production was produced In order to reduce amount of $Na_2O$, Loss of Boiling (L.O.B), Loss of Ignition (L.O.I), Conductivity and PH which are present in the waste $CO_2$ molding sand below the reclamation effect, more than 50% of elimination for reclamation was required. It was found that the waste $CO_2$ molding sand does not contain a harmful component designated by industrial waste materials. Reclamation of the waste $CO_2$ molding sand was practically achieved by an abrasive-dry reclamation process. According to bench time of the sodium silicate-bonded $CO_2$ molding sand, reduction of compressive strength and surface stability index(S.S.I) become slowdown. Therefore, the reclaimed sand could be allowed the reuse of molding sand in $CO_2$ molding process including core sand.

• 자원환경지질
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• 제16권2호
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• pp.65-78
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• 1983

This report deals with the sedimentological study of the littoral sand of beaches in the Busan area. The purpose of this report is to know the grain size, mineralogical composition, heavy mineral and clay mineral of the beach sands, and gravity measurements of the Nagdong River Deltas. 1) As a whole, the littoral sand of the beaches are composed of uniformly medium grained, moderately sorted and nearly symmetrical. The barrier sand of the Nagdong Estuary is composed of fine grained, well sorted and nearly symmetrical. 2) The littoral sand of the beaches is transported by saltation and rolling. The barrier sand of the Nagdong Estuary is transported by suspension and saltation. 3) In the littoral sand of the beaches, the ratio of feldspar to quartz is 1 :2.31 and in the barrier sand of the Nagdong Estuary 1:1.40. 4) The content of heavy mineral of samples ranges from 0.54 to 3.87 %. The principal heavy minerals are hornblende, pyroxene, epidote, garnet, leucoxene, zircon, apatite, magnetite, hematite and ilmenite with minor accessories of rutile and olivine. 5) The x-ray diffraction analysis of the clay mineral informs the existence of quartz, feldspar, kaolinite and montmorillonite. The montmorillonite is considered to have been derived from the alteration of acidic volcanic rocks. 6) To determine the depositional structure of the Nagdong Estuary, Gravity measurements were made. Free air anomaly ranges from 14.5 mgal to 33.5 mgal and Bouguer anomaly ranges from 14.3 to 23.5 mgal and both are closely related to the topography. According to the interpreted layer structure, the upper layer composing sand, silt and clay, the intermediate layer composing sand with gravel, the lower layer composing weathered and soft rock, and bed rock composing hornfels or andesite. 7) The depositional environments of the study, the littoral area is dominated by the marine environment and the Nagdong Estuary by the mixed environment.

• 한국지반공학회논문집
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• 제26권4호
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• pp.27-36
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• 2010

사질토의 상태정수를 현장시험으로부터 추정하기 위해 실내 챔버에 조성된 부산사에 대해 딜라토미터 시험을 수행하였다. 시험결과, 수평증폭계수($K_D/K_0$)와 상태정수($\Psi$)의 관계는 반대수축상에서 선형관계를 보였으나, 응력이력에 의한 잔류수평응력의 영향으로 과압밀 시료가 정규압밀 시료에 비하여 동일한 상태정수에서 수평증폭계수의 값이 작게 평가되었다. 유효응력으로 정규화된 딜라토미터 계수($E_D/\sigma_m'$)와 상태정수의 관계는 반대수축상에서 선형관계를 만족하였으며, 다소의 분산은 있으나 응력이력에 관계없이 하나의 관계식으로 표현 기능하였다. 다만 응력수준의 영향으로 과압밀 상태보다 정규압밀 상태의 분산이 약간 크게 발생되었으며 구속압이 증가할수록 관계곡선이 하향 이동하는 경향이 나타났다. 기존에 연구된 Ticino sand 및 Toyoura sand와 비교한 결과, $K_D/K_0-\Psi$ 관계는 혼재되어 분포하였으나, $E_D/\sigma_m'-\Psi$ 관계는 시료 압축성의 영향으로 Toyoura sand가 Ticino snad 및 부산사의 상부에 위치하였다.

• 한국환경과학회지
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• 제22권3호
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• pp.371-378
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• 2013

After identifying species by collecting the suspended and attached algae mat inhabiting in the slow sand-filter, Spirogyra sp., Mougeotia sp. and Closterium sp. were main green algae and Synedra sp. was diatom algae. Among them green algae Spirogyra sp. was dominant species. A result of observing the life mode of apple snail for a month after introducing into the slow sand-filter, apple snail eggs were discovered on the filter walls 2 weeks after introducing, 4 weeks later lots of eggs were observed all of the slow sand-filter walls, it means there is no problem for apple snail to live in the slow sand-filter. The observation result for algae removal potential by introduced apple snail after 2 months later, slow sand-filter where apple snail were introduced, a few algal mat were observed. On the other hand, no introduced apple snail into the slow sand-filter, lots of suspended algal mats were formed in the water and attached algal mats on the sand surface as well, these algal mat induced much of operating problems.

• 대한환경공학회지
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• 제34권2호
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• pp.73-78
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• 2012

낙동강 원수와 급속 사여과 처리수중에 함유된 인공 사향물질(Synthetic Musk Compounds, SMCs) 3종에 대해 오존처리 공정에서의 제거특성을 살펴본 결과, Musk Ketone (MK)이 AHTN (7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene)과 HHCB (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[c]-2-benzopyran)에 비해 오존처리에 의한 제거율이 낮게 나타났다. 그리고 동일한 운전조건에서 원수에 함유된 SMCs의 제거율은 원수 중에 함유된 오존 소모물질들에 의한 영향으로 급속 사여과처리수에 함유된 경우보다 제거율이 훨씬 낮았다. 오존 투입농도 0.5~10.0 mg/L에서 낙동강 원수와 급속 사여과 처리수 중에 함유된 3종의 SMCs에 대한 제거 속도상수(k)는 오존 투입농도가 증가할수록 급격히 증가하는 경향을 나타내었고, 반감기 역시 오존 투입농도 증가에 비례하여 급격히 감소하였다. 전/후오존 공정이 갖추어진 낙동강 하류에 위치한 정수장들의 경우, 전오존 공정은 최대 1.5~2.0 mg/L의 오존 투입농도로 2~4분 및 후오존 공정은 최대 2.0~2.5 mg/L의 오존 투입농도로 6~8분 정도의 체류시간을 가지도록 설계되어져 있어 비교적 고농도의 SMCs가 유입될 경우에는 오존처리만으로는 이들 물질들에 대한 제어가 어려운 것으로 나타났다.