• 한국물환경학회지
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• 제37권2호
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• pp.75-91
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• 2021

Ocean dumping manure was prohibited in Korea until the end of 2012. Undumped manure was treated by resourcification, purification, and public process in a facility. But poor storage of untreated manure and overproduced compost can pollute river water. In this study, linear regression, Mann-Kendall, Seasonal Mann-Kendall, LOWESS trend, and Spearman's correlation analysis were conducted for investigating the changes in the water quality of Bukhan and Imjin river before and after the prohibition of ocean dumping. In 2017, the Imjin Riv er basin had more than 5.7 times liv estock breeding heads than the Bukhan Riv er basin and more than 3.5 times livestock manure. The areas of land, farmland, and nutrient balance were also higher in the Imjin River basin. Since the two basins have different environments, it is expected that the characteristics of changes in water quality due to the increase in livestock manure generation and treatment methods will be different when comparing the water quality trends before and after the ban. The result of the trend analysis revealed a decrease in EC before the ban but an increase afterward. T-N and BOD of Imjin river increased slightly before the ban but demonstrated great enhancement thereafter. Other sites and T-P exhibited no trend. The correlation analysis result showed that the increase in the number of livestock rearing was correlated with the increase in T-P of Bukhan River and BOD of Imjin River. The increase in livestock manure production was not correlated with the Imjin River basin, while a correlation was observed with the Bukhan River with an increase in T-N and EC and the decrease in T-P.

• 한국농공학회논문집
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• 제52권5호
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• pp.37-45
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• 2010

Manure recycling as fertilizer is one of solutions for the environmental problem related with livestock manure treatment as well as the ocean dumping ban act prohibiting manure disposal to the ocean. For the manure disposal, forest area can be a candidate place because the area has a wide range of applicable sites. However, the manure application to the forest has a possibility of causing environmental impacts including water quality problems due to nutrient loading. Therefore it is necessary to investigate water quality impact from manure disposal to the forestry plantation. In this study, ground and soil water quality had been monitored in the bio-circulation experimental forest where low concentration liquid manure (LCLM) was applied. Soil and groundwater samples were collected and analyzed weekly from April to October in 2008 and 2009. The mean and variation of NO3-N concentration in soil water of LCLM treatment places showed higher concentration than the reference places declining during growing season. In the case of groundwater from monitoring well in the downstream of disposal site, the $NO_3$-N concentration was 3.59 mg/L in 2008 and 3.26 mg/L in 2009 in average showing higher concentration than the reference well although the concentration was not exceed the national drinking water standard. To investigate the source of nitrate, $\delta^{15}N$ isotope analysis was also implemented. Its result showed that the LCLM application could be the nitrate source requiring further long-term monitoring soil and water quality.

• 한국산학기술학회논문지
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• 제16권11호
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• pp.7227-7236
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• 2015

수산물 가공폐수의 배출특성 결과, 불규칙한 유입부하로 안정적인 처리에 어려움이 있는 것으로 조사되었다. 수산물 가공폐수와 같은 고농도 유기성 폐수처리에는 가압부상조 운영이 매우 중요하다. 가압부상조의 운전 factor를 조사한 결과, A/S ratio 0.05(설계기준 0.01), 가압공기 압력은 8bar(설계기준 6bar), 가압탱크 압력은 6bar(설계기준 4.5bar), HRT는 60sec(설계기준 10sec)로 운영하였다. 또한 재순환율은 40% 이상(설계기준 30%), 표면 부하율은 $13.7m^3/m^2{\cdot}hr$ 이하(설계기준 $17.7m^3/m^2{\cdot}hr$ 이하)로 변경하여 최초 설계기준에 비하여 운전 factor를 유입특성에 따라 변화시켜 가압부상조의 성능을 향상시켰다. 유입부하 검토결과, BOD는 유입 설계기준 대비 140.7%, $COD_{Mn}$는 120.32%, SS는 106.3%로 조사되었으며, T-N은 135.5%, T-P는 173.3%로 설계기준보다 높게 유입되고 있었다. 처리시설의 연간 운영비를 조사한 결과, 슬러지 처리비(27.7%)와 약품비(26.0%)가 높은 비중을 차지하였으며, 슬러지 처리비는 해양투기 금지로 더욱 상승할 것으로 판단된다. 수산물 가공폐수 처리단가는 1톤당 3,858원으로 하수처리비용(142.6원/ton)에 비해 27배 이상으로 높게 조사되었는데, 이는 고농도의 유기물과 영양염류를 포함하고 있기 때문으로 판단된다.