Spent Calgon Filtrasorb activated carbon (SAC) from glycerine deodorization unit was evaluated for the removal of methylene blue (MB). The SAC was used without further modification. The SAC was characterized for BET surface area, pH, pHpzc and FTIR to determine the textural and chemical properties of SAC. The batch adsorption study of MB was carried out under different initial concentrations (5–500 mg/L), pH (2–11) and contact time (0–200 h). The SAC was found to have high BET surface area, pore volume and average pore diameter of 735 m2/g, 0.292 cm3/g and 2.56 nm, respectively. The properties of SAC contributed to high MB adsorption capacity of 283 mg/g. The equilibrium data fitted well with Langmuir model, indicating monolayer adsorption; while the activation energy (Ea) of Dubinin–Radushkevitch (D–R) model is lower than 8 kJ/mol, signifying physisorption. The adsorption kinetics was best illustrated by pseudo-second-order model, while the intraparticle diffusion and Boyd models suggested that film diffusion is the rate-controlling step. These findings showed that Calgon Filtrasorb SAC from glycerine deodorization unit can be potentially reused an adsorbent for the removal of dyes.
It is necessary to develop a device for the design of wet scrubber with a more efficient deodorization performance in order to enhance the odor reducing effect of the wet scrubber. Therefore in this study, the superiority of the new wet scrubber with the centrifugal separation function different from the conventional wet scrubber was analyzed by the computational fluid dynamics. From CFD analysis, the pressure and velocity distribution, the peak vorticity, the retention time and the flow uniformity were calculated and compared with the performance characteristics of the centrifugal separator. As the results of CFD analysis, the peak vorticity and retention time of the gas flow were increased about 22% and the flow uniformity was improved about 7.2% by the centrifugal separator. Therefore the centrifugal separator in the wet scrubber will improve the deodorizing effect and the cleaning condition of the gas.
This paper presented experimental results for photocatalytic air cleaner removal performance for malodorous compounds generated from rest room. Photocatalytic oxidation (PCO) efficiency was up to 80∼ 90% for NH3 in chamber, 29.3% for H2S, 79.6% for CH3SH, 58.8% for DMDS individually. PCO efficiency for DMS(Dimethy Sulfide) and DMDS(Dimethyl Disulfide) were relatively lower than that of NH3 and CH3SH, this results indicate that DMS and DMDS removal process were effected by by-products of photocatalytic oxidation and humidity. Ozone was relatively low (below 5ppb) under the test conditions through photocatalytic oxidation. It is necessary to test a reliability of the air cleaner for a longtime under the various indoor conditions. But, prototype photocatalytic air cleaner will promise useful air cleaner for indoor air quality applications.
The deodorization performances of ammonia, acetic acid and acetaldehyde were tested for each of all forty five air cleaners sold in the online shops and department stores. The removal performances of toluene and formaldehyde were also investigated and the results were compared to the deodorization performances for the air cleaners. Filter-type and complex type air cleaners which used activated carbon filters showed superior in odor removal performances to those of ionizer type and wet type air cleaners. Toluene and formaldehyde were readily removed for the most of filter-type and complex type air cleaners. Ionizer air cleaners had little removal ability for the toluene and formaldehyde.
현재 국내 생활폐기물 고형연료화 시설은 SRF 생산에 초점을 맞춰 생물할적 처리공정이 결여된 MT 시설의 형태로 도입되었는데 이로 인해 설계 운전범위보다 높은 함수율의 생활폐기물 반입시에 선별 효율 감소로 폐기물 반입량 대비 30~45%의 비율로 잔재물이 발생하고 있다. 이런 잔재물은 함수율 40% 이상을 보이고 있어 직매립시에서 오염부하를 증가시키고, 또한 매립에 따른 처분비용 발생으로 전체 시설 운영비의 약 20%를 차지하고 있는 실정이다. 매립지 부하 경감 및 고형연료화 시설의 운영비 저감을 위해 발생 잔재물을 재활용 할 필요가 있는데 양 및 질적인 측면을 볼 때, 함수율을 떨어뜨린 후 선별하게 되면 추가적인 SRF를 회수할 수 있다고 판단하여 잔재물의 함수율 저감을 위해 생물학적 처리공정인 Bio-drying을 적용하였다. 이는 폐기물 내 생분해성 유기물질이 미생물에 의해 호기성 분해시 발생하는 열을 이용해 폐기물의 수분을 건조시키는 방법으로 건조과정에서 자연건조 대비 다량의 배가스(악취 포함)를 배출하게 된다. 이에 본 연구에서는 생활폐기물 잔재물(저품위 혼합폐기물)에 대해 Bio-drying으로 건조하는 과정에서 발생하는 악취 특성 분석 및 해당 악취에 대해 약액세정과 활성탄이 적용된 복합 탈취설비의 성능을 확인하고자 하였다.
A aqueous solution of malodorants (i.e., n-valeraldehyde, n-valeric- acid, 2-methylisoborneol, and trimethylamine) was exposed to 200kHz ultrasound with a power of 6.0W/cm2 per unit volume in a sonochemical reactor under room temperature and atmospheric pressure condition. The concentration of malodorants decreased with irradiation time, indicating pseudo-first-order kinetics. The removal efficiency of malodorants was about from 50% to 96% decomposed after 90 minutes sonication. At the deodorization, it was determined by triangle odor bag(TOB) method for odor sensory measurement, and it indicated that over 60% of relative odors were deodorized with degradation by the sonication.
Continuous deodorization of malodorous sulfur compounds by Thiobacillus neapolitanus R-10 immobilized onto a polypropylene pellet was studied using a column reactor at 30℃. The maximum amounts of immobilized cells was 5.3 g/ℓ polypropylene with 5 × 7.5㎜ in pellet size, and the amounts of immobilized cells in the higher part of the column was as twice as in the lower part. The optimum pH and temperature for removal of dimethyl sulfide were 6.0 and 30℃, respectively. When 5-20 ㎕/ℓ of hydrogen sulfide and methylmercaptan were employed 98% of removal efficiency were achieved. In contrast, lower concentrations of dimethyl sulfide and dimethyldisulfide should be supplied to meet satisfactory deodorization efficiency. The immobilized cell column was successfully operated for the deodorization of mixture of sulfur compounds over 15 days without significant loss of initial activity achieving high efficiency.
The present study was performed to develop the removal system of the offensive gases, including hydrogen sulfide of acid gas, ammonia or amine of base gas, from the nightsoil treatment plant. In order to remove the offensive gases, the Fe-EDTA system liquid phase catalytic oxidation method with the bubble lift column reactor was employed. From the results obtained it was confirmed that the offensive gases can be deodorized simultaneously and also hydrogen sulfide of acid gas, ammonia of base gas completely removed at pH 6.45. In addition, as input gases feed rate the efficiency of acid gas did not change but the efficiency of base gases decreased to approximately 90% at pH 6.0. From the result of particle size analyzer, it was found that the particle sizes including sulfur and other impurites grew up to 21μm over 72hour reaction time.