본 연구는 온실의 온도와 CO2농도를 높이기 위해 DME버너용 연료로 DME가스를 사용했을 때 DME 연소가스의 성능을 결정하고 겨울에 상추와 양배추의 엽록소 함량 그리고 무게와 건조무게에 대한 영향정도를 조사하기 위해 수행되었다. 각각 온실1과 온실2에 처방 된 DME-1과 DME-2 처방은 덕트의 평균 DME 유량 17.4 m3 min-1과10.2 m3 min-1으로 구성됐으며, 대조군(DME-3)으로 남겨진 온실3에는 DME 가스가 공급되지 않 았다. DME 공급 시간은 각각 주차 별로 1주차는 하루당 0.5시간, 2주차는 1시간, 3주차는 1.5시간, 4주차는 2 시간으로 설정하였다. 각각 처방마다 엽록소 함량과 상추와 배추의 건조 전, 후 중량을 측정했으며, 연구결과 무처리구인 온실3과 비교하여 온실1과 온실2 의 CO2 농도는 각각 265%, 174% 증가하였고, 온도의 경우 4.8oC, 3.10oC 상승하였다. DME 가스를 제외한 다른 조건이 같은 온실에서 재배된 상추와 양배추의 엽록소 함량과 생체중, 건물중은 온실1에서 (유의적으로) 가장 높았으며, 온실2는 대조구 온실보다 높았다. 이러한 결과는 DME가스 연소에 의한 CO2 농도 차이에 기인된 것으로 판단된다. 일반적으로 가스연소에 의해 발생되는 유해가스 증상은 나타나지 않았으며 동절기 난방과 CO2 공급이 동시에 필요할 경우 DME가스가 기존의 경유 또는 LPG 등을 대체할 수 있는 가능성을 확인하였다. 향후 정밀한 연구를 통하여 효율적인 난방방식으로의 검토가 적극 필요하다고 판단된다.

The experiment was conducted to determine the performance of DME combustion gas when used as a fuel for DME burner for raising temperature and CO2 concentration in greenhouse and also to examine its effects on chlorophyll content, and fresh and dry weight of lettuce and Chinese cabbage. DME-1 and DME-2 treatments consisted of average DME flow quantity in duct were 17.4 m3 min-1 and 10.2 m3 min-1 respectively to greenhouse-1 and greenhouse- 2 and no DME gas was supplied to greenhouse-3 which was left as control (DME-3). DME supply times were 0.5 hr day-1, 1 hr day-1, 1:30 hrs day-1 and 2 hrs day-1 on week 1, 2, 3, and 4 respectively. Chlorophyll content and fresh and dry weight of lettuce and Chinese cabbage were measured for each treatment and analyzed through analysis of variance with a significance level of P<0.05. The result of the study showed that CO2 concentration increased up to 265% and 174% and the level of temperature elevated 4.8oC and 3.1oC in greenhouse-1 and 2, respectively as compared to greenhouse- 3 due to application of DME combustion gas. Although, the same crop management practices were provided in greenhouse-1, 2 and 3 at a same rate, the highest change (p<0.05) of chlorophyll content, fresh weight and dry weight were found from the DME-1 treatment, followed by DME-2. As a result, DME combustion gas that raised the level of temperature and CO2 concentration in the greenhouse-1 and greenhouse-2, might have an effect on growth of lettuce and Chinese cabbage. At end of experiment, the highest fresh and dry weight of lettuce and Chinese cabbage were measured in greenhouse-1 and followed by greenhouse-2. Similarly chlorophyll content of greenhouse-1 and greenhouse-2 were more compared to greenhouse-3. In general, DME was not producing any harmful gas during its combustion period, therefore it can be used as an alternative to conventional fuel such as diesel and liquefied petroleum gas (LPG) for both heating and CO2 supply in winter season. Moreover, endorsed quantify of DME combustion gas for a specified crop can be applied to greenhouse to improve the plant growth and enhance yield.

Abstract
Introduction
Materials and Method
    1. Experimental Design
    2. Properties of DME
    3. Data Collection and Analysis
Results and Discussion
    1. Temperature and CO2 pattern
    2. Fresh and Dry weight of Lettuce and Chinese cabbage
    3. Chlorophyll content in Lettuce and Chinese cabbage
Conclusions
Literature Cited
적 요

• Jayanta Kumar Basak(Department of Bio-systems Engineering, Gyeongsang National University/Department of Environmental Science and Disaster Management, Noakhali Science and Technology University) | 쟌타 구마 바삭
• Waqas Qasim(Department of Bio-systems Engineering, Gyeongsang National University) | 와카스 카심
• Fawad Khan(Department of Bio-systems Engineering, Gyeongsang National University) | 파와드 칸
• Frank Gyan Okyere(Department of Bio-systems Engineering, Gyeongsang National University) | 프랑크 갼 오시레
• Yongjin Lee(Department of Bio-systems Engineering, Gyeongsang National University) | 이용진
• Elanchezhian Arulmozhi(Department of Bio-systems Engineering, Gyeongsang National University) | 에린지 아루모지
• Jihoon Park(Department of Bio-systems Engineering, Gyeongsang National University) | 박지훈
• Wonjun Cho(Bio Friends Inc.) | 조원준
• Hyeon Tae Kim(Department of Bio-systems Engineering, Gyeongsang National University) | 김현테 Corresponding author