To mitigate carbon emissions, the government aims to transition to renewable energy sources including hydrothermal energy, specifically through wastewater heat recovery. This process involves extracting heat from wastewater or treated water. However, assessments of demand sources for local cooling and heating have predominantly focused on the proximity of nearby facilities, without conducting comprehensive demand analyses or defining explicit supply areas. This study proposes a methodology for prioritizing suitable wastewater treatment plants (WWTPs) for the implementation and expansion of renewable energy. The methodology is based on the gross floor area of potential wastewater heat demand surrounding WWTPs. Initially, potential supply and demand sources were identified based on the capacity of WWTPs and the gross floor area of buildings capable of utilizing wastewater heat. In the Republic of Korea, 330 WWTPs with a capacity of 5,000 m3/day or more have been recognized as demand sources for wastewater heat recovery. The provision of treated wastewater to structures located within a 500 m radius of the WWTPs for heat recovery is considered a feasible option. The potential wastewater heat demand and renewable energy cluster were identified among the surrounding buildings and complexes A total of 13 potential supplies were identified, provided that the gross floor exceeded 60,000 m². Finally, after prioritizing based on WWTPs with these conditions, the underground plant located in the downtown area was ranked as the highest priority. If further analysis of economic feasibility, CO2 reduction, and energy efficiency are conducted, this approach can be expanded and applied within the framework the Water-Energy Nexus. Wastewater heat can be utilized not only as a renewable energy source but also as a means to enhance wastewater reuse through the supply of treated wastewater.

In this study, dual drainage system based runoff model was established for W-drainage area in G-si, and considering the various rainfall characteristics determined using Huff and Mononobe methods, the degree of flooding in the target area was analyzed and the risk was compared and analyzed through the risk matrix method. As a result, the Monobe method compared to the Huff method was analyzed to be suitable analysis for flooding of recent heavy rain, and the validity of the dynamic risk assessment considering the weight of the occurrence probability as the return period was verified through the risk matrix-based analysis. However, since the definition and estimating criteria of the flood risk matrix proposed in this study are based on the return period for extreme rainfall and the depth of flooding according to the results of applying the dual drainage model, there is a limitation in that it is difficult to consider the main factors which are direct impact on inland flooding such as city maintenance and life protection functions. In the future, if various factors affecting inland flood damage are reflected in addition to the amount of flood damage, the flood risk matrix concept proposed in this study can be used as basic information for preparation and prevention of inland flooding, as well as it is judged that it can be considered as a major evaluation item in the selection of the priority management area for sewage maintenance for countermeasures against inland flooding.

들기름 및 미강유를 베이스로 개발한 혼합 식용유는 오메가-3 지방산인 리놀렌산 함량이 약 20% 정도로 매우 높다. 이는 기존의 일반 식용유 중 오메가-3 지방 함량이 매우 높은 콩기름과 카놀라유의 리놀렌산 함량이 각각 6% 및 10% 내외인 점을 감안하면, 이들 식용유에 비하여 새로 들기름과 미강유를 혼합한 식용유는 2~3배 높은 비율로 오메가-3 지방산을 제공할 수 있어서, 오메가-3 지방산 섭취가 부족한 현대인의 식단에서 중요한 오메가-3 지방산 급원으로서의 역할을 할 수 있을 것이다. 뿐만 아니라, 토코페롤 함량도 약 46.77 ㎎/ 100 g oil 정도인데, 가장 주목할 일은 토코페롤 동족류 중 비타민 E의 활성이 가장 강한 알파-토코페롤(31.71 ㎎/100 g oil)이 가장 많이 존재하여, 총 토코페롤의 64%를 차지하고 있어서 비타민 E로서의 기능이 높다. 혈중 콜레스테롤 함량을 낮추는 기능성이 알려진 파이토스테롤 함량이 들기름과 미강유를 혼합한 식용유에 약 7,200 ppm 함유되어 있어, 일반적인 식용유의 3,000 ppm의 약 2.3배에 달한다. 본 연구에서 개발한 들기름과 미강유를 혼합한 식용유는 일반적인 식용유인 콩기름과 거의 유사한 산화안정성을 갖는 것으로 확인되어, 일반 들기름에 비하여 현저히 높은 산화안정성이 확보되었다.