본 연구에서는 복막 투석 시스템에 있어서, 요소를 가수분해 후 발생하는 암모니아를 제거하기 위하여, 방사선 그라프트 중합법에 의해 다공성 중공사막에 술폰산기(SO3H)를 도입시킨 양이온 교환막(이때 얻어진 막을 SS막이라 함)을 합성하였다. 여기에 금속이온(Cu, Ni, Zn)을 이용하여 그라프트 체인을 가교시킨 이온가교형 양이온 교환막(이때 얻어진 막을 SS-M막이라 함)을 합성하여, SS막과 SS-M막의 투과 유속과 암모니아의 흡착에 대하여 고찰하였다. 술폰산기 밀도에 따라 순수투과 유속은 술폰산기 밀도가 높아짐에 따라 투과 유속이 급격히 감소하였으나, 금속 이온이 도입됨에 따라, 투과 유속이 빨라진다는 것을 알 수 있었다. SS막의 경우 암모니아 흡착은 이온교환기 용량에 따라 1 : 1로 흡착되었고, SS-M막 보다 높은 흡착량을 나타났다. 또한, SS막, SS-M막 모두 pH 9에서 가장 높은 흡착량을 나타냈다.
Removal of siloxane compounds is very important to protecting the biogas energy conversion system from decreased efficiency and parts damage. Among various siloxane removal technologies, adsorption towers are mostly used for performance and ease of operation. However, due to the difficulty of measuring the concentration of siloxane compounds in the gas stream and the complicated matrix of siloxane compounds, adsorption characteristics are not well known. In this study, the adsorption characteristics for multi siloxane components are experimentally studied. Four siloxane components are vaporized in the nitrogen stream supplied continuously to a lab-scale adsorption tank with commercially available silica gel or activated carbon and an FTIR (Fourier-transform infrared spectroscopy) analyzer was used for the online siloxane analysis to find out the adsorption characteristics. While a mixture of L2, L5, D4 and D5 adsorption capacity of silica gel and activated carbon are similar -11.13 and 11.56wt% respectively-adsorption characteristics of each adsorbent was well distinguished in terms of breakthrough behavior. Silica gel shows sequential breakthrough for each siloxane compound and a more noticeable unique time range for Rc > 1, while relatively simultaneous breakthrough was shown for activated carbon adsorbents.
Interest in the measurement of siloxane which reduces energy efficiency of biogas, has increased with its market extend. Even though the impinger absorption method takes long sampling time of 2-3 hours and need a complicated equipment, it has been typically used for the sampling method of siloxane. This study was conducted to apply the gas bag sampling method with tedlar bag and aluminium bag for improving the method of siloxane sampling. To compare efficiencies of siloxane sampling, the manufactured gas, landfill gas, and digestion gas were used as sample gases. According to the result, materials of gas bags did not cause measurement error and there was no loss of siloxane by adsorption on the inner surface of gas bag. The result of D4 calibration in the tedlar bag, showed higher than 0.99 in the coefficient of determination. In case of digestion gas, the analysis results of two samples collected by the tedlar bag and the impinger absorption were almost same. The differences of analysis result between landfill gas and digestion gas were considered due to the short sampling time and the absence of gas storage tank.