하수슬러지의 퇴비화를 촉진할 수 있는 방안을 검토하기 위하여 2월 및 8월에 하수슬러지를 채취하여 생균수를 측정한 결과 하수종말처리장에서의 폐수처리시 유입수량 변동, 양이온성 polyacrylamide의 사용량 및 기후 변동을 포함하는 여러 조건의 변화에 따라 미생물 종과 미생물수의 변동이 많았으며, 미소후생동물의 종류 및 활동성도 계절에 따른 차이가 있었다. 양이온성 polyacrylamide가 미생물 생육에 미치는 영향을 조사한 결과 양이온성 polyacrylamide의 농도가 0.8% 이상일 때는 모든 균주의 생육이 저해되었으나 0.2% 이하에서는 균 생육에 지장을 초래하지 않았다. 하수슬러지의 퇴비화 과정중에 관여하는 미생물의 균종과 균수를 조사하고자 하였으나 미생물의 생태적 생리적 특성과 퇴비화의 일정한 상관관계를 도출할 수는 없었다. 그러나 유기물 함량과 bulking agent로 톱밥을 투여하였을 경우 미생물의 균종과 균수의 증가가 관찰되었다. 하수종말처리장의 폭기조 투입직전 활성슬러지, 폭기조내 활성슬러지, 하수슬러지와 bulking agent로 톱밥을 혼합처리하여 관찰한 결과 Fragilaria sp., Proales sp., Vorticella sp., Schizothrix sp., Anabaena sp., Zoothaminium sp., Epstylis sp., Arcella sp., Balantidium sp., Actinophrys sp., Synedra sp., Euglypha sp., Ulothrix sp., Anacystis sp., 및 Clostium sp. 등의 다양한 미소 후생동물이 관찰되었다. 특히 전기간에 걸쳐 Fragilaria sp., Proales sp., Vorticella sp. 몇 Schizothrix sp.가 관찰되었다. 슬러지 내에 존재하는 세균, 효모, 방선균, 곰팡이, 미세조류, 원생동물 및 하등동물은 하수슬러지의 퇴비화 또는 감량화 과정 중에 존재하여 공극의 확보와 같은 물리적인 퇴비화 촉진과 생물학적 분해작용에 의한 퇴비화 촉진 효과를 얻을 수 있을 것이다.

The feasibility study of using converter slag as a solidifying agent of digested sewage sludge cake has been performed. The availability of converter slag as solidifying agent has been investigated by several trial tests. Based on the trial test results, the optimum mixing ratios of sludge cake and solidification additive are estabilished. Finally the solidification characters of sludge cake are elucidated by SEM and EDS. It is ascertained that converter slag with a small amount of quicklime enhences the solidification. From the result of pH test, overall pH of specimens tends to decrease slowly with curing time. After solidifying specimens had been cured for 7 days, these are water-cured for 24 hours. The weight and strength of all the specimens are nearly the same regardless of the mixed ratios of solidifying agent. The result of leaching tests for four heavy metal ions, Cd, $Cr^{6+}$, Pb and Cu show that the leaching strength becomes below the decision criteria of the specific wastes, respectively. The SEM observation of the delicate structure shows that needlelike crystals appear after solidification which are not observed before. From the EDS analysis, it is found that the main ingredients of needlelike crystals are Ca, Si, Al and O.

The dewatering characteristics of the sewage sludge was investigated through the experimental observations and model simulations. The activated sludge and the anaerobically digested sludge were examined for the dewaterability evaluation within the pressure range of $0{\sim}10^6N/m^2$. Modified Buchner funnel test and compression test by the consolidometer were conducted to evaluate average specific resistance, porosity, and moisture percentage of filter cake. Shirato's technique of compression-permeability test was followed for the pressure range lower than about $10^2N/m^2$. The flocculation effects on sludge dewatering was also examined for ferric chloride and polymeric flocculant. The application of hydrated lime which can be used for flue-gas desulfurization showed improved moisture percentage, and was thought to have positive feasibility in combined system of sludge dewatering and incineration. Determined characteristic constants were applied to Tiller's cake filtration model to simulate liquid pressure distribution and porosity distribution in cake. Model simulations showed a sharp drop of the porosity close to the cake-medium interface for the highly compressible material such as the activated sludge and the anaerobically digested sludge.

Laboratory experiments were conducted to investigate the effect of digestion temperature on the settleability and dewaterability of anaerobically digested sludge. The digesters were operated at a hydraulic retention time of 20 days with a loading rate of 0.63~0.66kg volatile solids per cubic meter per day at the temperature of $35^{\circ}C$ and $55^{\circ}C$. A mixed primary and secondary municipal sludge was used as a feed. The interface height of the sludge during settling test was recorded to identify settleability. As a measure of dewaterability of the sludge, specific resistance and capillary suction time were also measured with and without chemical conditioning. Higher digestion efficiency was obtained at $55^{\circ}C$ than $35^{\circ}C$. However, the settleability and dewaterability of the sludge at $35^{\circ}C$ were quite higher than those of the sludge digested at $55^{\circ}C$. The optimum dosages of ferric chloride for sludge conditioning were 0.4% and 0.6% at $35^{\circ}C$ and $55^{\circ}C$, respectively. The filtrate COD of the sludge digested at $55^{\circ}C$ was higher than at $35^{\circ}C$, which means that poor dewaterability of the sludge result in high filtrate COD.

This study investigated microbial communities and their diversity in a full-scale mesophilic anaerobic digester treating sewage sludge. Influent sewage sludge and anaerobic digester samples collected from a wastewater treatment plant in Busan were analyzed using high-throughput sequencing. It was found that the microbial community structure and diversity in the anaerobic digester could be affected by inoculation effect with influent sewage sludge. Nevertheless, distinct microbial communities were identified as the dominant microbial communities in the anaerobic digester. Twelve genera were identified as abundant bacterial communities, which included several groups of syntrophic bacteria communities, such as Candidatus Cloacimonas, Cloacimonadaceae W5, Smithella, which are (potential) syntrophic-propionate-oxidizing bacteria and Mesotoga and Thermovigra, which are (potential) syntrophic-acetate-oxidizing bacteria. Lentimicrobium, the most abundant genus in the anaerobic digester, may contribute to the decomposition of carbohydrates and the production of volatile fatty acids during the anaerobic digestion of sewage sludge. Of the methanogens identified, Methanollinea, Candidatus Methanofastidiosum, Methanospirillum, and Methanoculleus were the dominant hydrogenotrophic methanogens, and Methanosaeta was the dominant aceticlastic methanogens. The findings may be used as a reference for developing microbial indicators to evaluate the process stability and process efficiency of the anaerobic digestion of sewage sludge.

In this study, we evaluated the effect of the type of sewage sludge (digested, non digested) on drying efficiency according to the polymer injection rate. The drying characteristics were shown using a near-infrared ray (NIR) and a microwave. As a result of the drying characteristics with NIR at a polymer dose ratio of 8%, the heating up period is up to 6 minutes after the start of the drying experiment. Afterwards, the constant rate drying period of the digested sludge (A, C and G sites) was 6 minute → 18 minute, showing a rapid decrease in moisture. On the other hand, non digested sludge (B, D, E, F, H, I, J and K sites) showed gradual drying characteristics compared to digested sludge until complete drying (10%). As the polymer dose ratio of 10% and 12%, the heating up period for digested sludge is up to 6 minute after the start of the experiment. Afterwards, the constant rate drying period of the digested sludge was 6 minute → 20 minute, showing a rapid decrease in moisture. On the other hand, the heating up period of non digested sludge was up to 10 minute after the start of the experiment, and the constant rate drying period was 10 minute → 22 minute, which was shorter than digested sludge. As a result of the drying characteristics with microwave at a polymer dose ratio of 8%, 10% and 12%, the constant rate drying period the digested sludge was 4 minute → 20~22 minute, showing a rapid decrease in moisture. On the other hand, non digested sludge of the constant rate drying period was 4 minute → 22~30 minute, which was longer than digested sludge.

This study executed evaluation of drying characteristics based on the polymer injection rate (8%, 10% and 12%) and the drying method[NIF(near-infrared ray). According to this study analyzed VS, VS/TS, and calorific value compared with ‘the auxiliary fuel standard of the thermoelectric power plant and the combined heat & power plant’. The results are as follows. In the case of NIR, the VS was slightly changed at the early stage of the material preheating period and the constant drying rate period with low moisture evaporation. But VS reduction was shown higher as moisture was dried. In the case of non-digested sludge with high VS content, the VS reduction rate by drying was shown lower than that of digested sludge. As the flocculant injection rate increased, the VS loss due th drying was found to be small. Also, the higher the flocculant injection rate was the longer the drying time. Especially, in the case of the NIR drying equipment, as the moisture content of sewage sludge decreased(moisture content 20∼40%), the loss of net VS also showed a tendency to increase sharply. It is shown that the high calorific value according to the drying time of the non-digested sludge was changed from 590 ㎉/㎏ to 3,005 ㎉/㎏ and from 539 ㎉/㎏ to 2,796 ㎉/㎏.

This study was performed to test the feasibility of thermophilic (55oC) co-digestion of municipal sewage sludge and food wastes. The management variables of co-digestion were the mixed ratios of municipal sewage sludge and food waste hydraulic retention times (HRTs). During the operation of thermophilic co-digestion, the reactor pH ranged from 7.0 to 7.5 and the reactor alkalinity remained above 3,200 to 4,000 mg/L as CaCO3. The volatile fatty acids concentration increased as the HRT shortened from 20 days to 10 days and the mixture ratio increased to 1:4, but did not reach toxic levels for co-digestion of sewage sludge and food wastes. Methane productivity increased gradually as the organic loading rate increased. Maximum methane productivity reached 1.03v/v-d at an HRT of 10 days and at the mixture ratio of 1:4. The TVS removal efficiency decreased from 70.6% to 58.3% as the HRT shortened from 20 days to 10 days. TVS removal efficiency ranged from 57.0% to 77% during the entire operation. It is likely that thermophilic co-digestion of sewage sludge and food wastes is a very effective method both to environmentally treat food waste and to economically produce gas for energy.

The treatment of sewage sludge using hydrothermal carbonization (HTC) can be an attractive alternative to conventional sludge disposal, but it should be accompanied by a drying process that uses Refuse-derived Fuel (RDF). However, the largest proportion of the energy demand in sludge-drying techniques is for heat sources, which has led to increased operation and maintenance costs. Recovering residual heat to apply to sludge drying significantly reduces both the operating cost and the greenhouse gas emissions. Suitable integration can be realized between drying technology and waste-to-energy (WtE) plants through the recovery of waste heat in WtE conversion as a heat source for sludge drying. This present paper investigates the indirect disk drying performance of the hydrothermal carbonization of sewage sludge using a low-temperature heat source in a laboratory and proposes an integration process with the drying technology of hydrothermal carbonization using waste heat. This paper concludes with experimental results that indirect disk drying technology can be applied in waste-heat recovery systems.

The amount of sewage sludge emission is gradually increasing every year. However, the Ocean dumping of sewage sludge was prohibited since 2012 by london convention 96 protocol. Therefore, ground disposal method for recycling organic waste or utilizing to energy technology was needed. The heat is generated when sewage sludge has decomposed with the aerobic microbes. In this study, the heat would be applied to dehydrate sewage sludge. The drying efficiency was evaluated according to Air Flow Rate(AFR) and the mixing proportion of the returned sludge. At the experiments used returned sludge Which was dried at 40% moisture content. As a result, the most high temperature was indicated when it mixed 30% and optimal AFR for maintaining aerobic condition was 200 mL/min.kg. During 14days of Biodrying, the highest temperature of reactor was 46℃ and maintained 5~7days are higher than 40℃. and also 18.8% of moisture was eliminated. These results show that using Biodrying to sewage sludge has economic potential compared to hot-air drying and can be one of the method to produce SRF with additional treatment.

최근 세계적으로 신재생에너지에 대한 관심이 커지고 있으며, 국내의 경우 폐바이오매스를 이용하는 친환경적인 에너지원으로써 활용할 수 있는 연료화 기술이 각광받고 있다. 국내 폐바이오매스는 크게 식품폐기물, 축산폐기물, 농산부산물, 임산부산물 및 하수슬러지 등으로 구분할 수 있으며, 이를 에너지원으로 전환하는 공정은 생물학적, 열화학적 공정으로 크게 구분할 수 있다. 국내 하수슬러지의 경우, 해양투기가 금지된 이후 에너지로 전환하여 재활용하기 위한 연구가 활발히 진행되고 있으며, 2014년 환경부에 따르면 전국 하수슬러지 처리시설은 98개 지자체에서 96개의 하수슬러지 처리시설이 운영되고 있고, 추가적으로 18개의 시설이 설계 및 건설되고 있다. 이 중 대부분의 시설은 고화 및 건조연료화를 통해 하수슬러지 처리량 저감을 하고 있으나, 고화 및 건조 연료화를 통한 하수슬러지 저감은 슬러지 자체의 높은 수분함량으로 인해 상대적으로 많은 에너지를 필요로 한다. 본 연구는 하수슬러지의 연료화를 위해 열화학적 공정 중 하나인 반탄화 공정을 이용하여 10 TPD급 폐바이오매스 반탄화 반응 시스템을 구성하였다. 원료물질인 하수슬러지의 높은 수분함량에 따른 열량 부족 문제를 극복하기 위해 폐목재를 혼합하여 사용하였으며, 반응온도(250-350℃)와 하수슬러지와 폐목재 혼합물의 혼합비(6:4, 4:6)에 대하여 운전 조건의 최적화 연구를 수행하였으며, 결과적으로 반탄화물 수율 70% 이상, 생성된 탄화물의 고위발열량 4,000 kcal/kg 이상의 운전조건을 도출할 수 있었다. 이와 더불어 생산된 반탄화물의 원소분석에 따른 C, H, O의 구성비는 저품위 석탄과 유사하게 나타남을 확인할 수 있었다.

The purpose of this study was to confirm the applicability of aerobic granular sludge (AGS) in the advanced sewage treatment process. Simulated influent was used in the operation of a laboratory scale reactor. The operation time of one cycle was 4 h and the reactor was operated for six cycles per day. The volume exchange ratio was 50%. The influent was injected in divisions of 25% to increase the removal efficiency of nitrogen in every cycle. As a result, the removal efficiencies of CODCr and TN in this reactor were 98.2% and 76.7% respectively. During the operation period, the AGS/MLVSS concentration ratio increased from 70.0% to 86.7%, and the average SVI30 was 67 mL/g. The SNR and SDNR were 0.073 0.161 kg NH4 +-N/kg MLVSS/day and 0.071 0.196 kg NO3 --N/kg MLVSS/day respectively. These values were higher or similar to those reported in other studies. The operation time of the process using AGS is shorter than that of the conventional activated sludge process. Hence, this process can replace the activated sludge process.

Using a mixture of sewage sludge and woody waste, optimal conditions for the bio-briquette process of carbonization residue were evaluated by compressive strength and bulk density. For the bio-briquette process, the optimal conditions were determined to be a molding temperature of 110oC and a moisture content of 10%. As the lignin in the carbonization residue can be used as a natural binder because of its plasticizing property, the bio-briquette process uses this property. To increase the compressive strength to >3.50 MPa, binders such as polyvinyl alcohol (PVA), guar gum, and starch were mixed in the carbonization residue. At 3 wt.% of PVA, 3 wt.% of guar gum, and 5 wt.% of starch, the conditions of binder usage were evaluated. To examine the cost in the bio-briquette production with the addition of the binder, the proportion of binder cost for the bio-briquette production were evaluated at 9.2% for PVA, 8.6% for guar gum, and 3.3% for starch, and starch was determined to be the best binder for the bio-briquette process.

The amount of sewage sludge that is emitted is gradually increasing every year. However, since 2012, because of the London Protocol, the oceanic dumping of sewage sludge has been prohibited. Therefore, for recycling organic waste, either the ground disposal method has to be used or technological solutions that develop energy from such waste have to be identified. Heat is generated when the sewage sludge has decomposed by aerobic microbes. In this study, to dehydrate sewage sludge, heat was applied and the drying efficiency was evaluated according to the air flow rate (AFR) and the proportional mixing of the returned sludge. For the experiments, returned sludge that was dried to 40% moisture content was used; consequently, the highest temperature was obtained when the moisture content was 30% and, for maintaining aerobic conditions, the optimal AFR was 200 ml/min·kg. During biodrying for 14 days, the highest temperature of reactor was 46℃, which was maintained at higher than 40℃ for 5-7 days; moreover, 18.8% of moisture was eliminated. These results show that using biodrying for treating sewage sludge has economic potential compared to hot-air drying; moreover, with additional treatment, biodrying can be one of the methods for producing Bio Solid Refuse Fuel (Bio-SRF).

유기성 폐기물 중 하나인 하수슬러지는 하수처리시설 중 1차 침전지와 생물학적 처리 단계에서 대량 발생한다. 이러한 하수슬러지는 재활용, 소각, 매립, 그리고 해양투기 방식으로 처리되어 왔으며, 국내에서는 발생량의 절반이상이 해양투기에 의해 처리되어왔다. 하지만 2012년 런던협약에 의해 해양투기가 금지됨에 따라 하수슬러지 처리에 관한 문제가 급부상 하였고, 최근에는 고형연료로의 재활용에 대한 많은 연구가 이루어지고 있다. 하지만 고형연료의 요구함수율을 충족시키기 위하여 탈수슬러지의 추가적인 건조과정이 필요하다. 하지만 높은 수분을 함유하고 있어 건조과정이 길어지고 고형연료로써 가치가 떨어져 경제적으로 어려움이 있다. 따라서, 본 연구에서는 하수슬러지의 건조방법 중 하나인 Bio-drying공법을 사용하였으며, 무분별하게 폐기되는 한약재 부산물을 혼합하여 적용하였다. Bio-drying은 생분해성 폐기물이 퇴비의 초기 단계를 통해 빠르게 가열되어 폐기물 흐름에서 수분을 제거하여 전체 중량을 감소시키는 과정이다. Bio-drying 공정에서 강제통풍뿐만 아니라 생물학적 열에 의해 건조 속도가 증가한다. 유기물의 호기성 분해를 통해 자연적으로 이용 가능한 생물학적 열의 주요 부분은 혼합 된 슬러지와 관련된 표면 및 결합수를 증발 시키는데 이용된다. 이 열 발생은 보충화석 연료가 필요 없고 최소한의 전력 소비로 Biomass의 수분 함량을 감소시킨다. 이에 본 연구에서는 Bio-drying을 통하여 하수슬러지와 한약재 부산물을 비율에 따라 혼합하여 Bio-drying의 20일 동안의 건조효율을 살펴보았다. 또한, 혼합물의 특성분석을 통하여 고형연료로써의 이용가능성을 평가해보았다.

하수슬러지와 음식물류폐기물을 포함한 유기성폐기물은 도시의 산업화, 인구 증가에 따라 그 규모와 발생량이 증가하고 있는 추세이다. 하수슬러지의 경우, 2003년 이후로 연평균 4.6 %씩 꾸준히 증가하여 2014년 기준 597 개소 하수처리장에서 약 10,112.7 ton/d 정도 발생되었다. 같은 해 음식물류폐기물은 총 생활폐기물 발생량의 27.4 %인 13,697.4 ton/d 규모로 배출되었다. 2012년 이후 음식물류폐기물을 필두로 해양투기가 전면 금지되면서 유기성폐기물의 육상처리와 신재생 에너지원으로서 효과적 활용에 대한 정책 추진과 연구가 진행되어왔다. 매립, 소각을 포함한 육상처리 방법 중, 바이오가스화는 혐기소화 과정에서 신재생 에너지원인 메탄가스를 생산하는 시설로 현 상황에 대응하는 새로운 방안으로 각광받고 있다. 전국 12개소 하수슬러지 단독 및 병합처리 바이오가스화 시설을 대상으로 현장조사 및 정밀모니터링을 실시하였다. 사계절 평균으로 정밀모니터링 결과를 정리하였을 때, 시설의 효율성 분석에서 유기물분해율은 VS 기준 55.2 %, CODcr 기준 48.7 %로 나타났다. 병합처리 시설의 유입 VS 농도는 단독처리시 2.59 % 보다 1.6배 높은 4.05 %로 조사되었다. 대상 시료의 원소분석시 평균 C/N비는 유입 7.7, 유출 6.5로 낮은 수치를 보였다. 시설의 안정성 분석에서 혐기소화조 유출액의 VFAs은 수분석시 427 mg/L, 기기분석시 42 mg/L로 분석되었으며, 소화슬러지 탈리여액의 질소와 인은 TN 1,229 mg/L, TP 155 mg/L 등으로 안정적인 운전범위에 속하였다.

국내 하수처리장의 바이오가스화 시설은 낮은 농축율로 인한 저농도 유입수, 공정 흐름별 운영기술에 대한 노하우 부족 및 관리 미숙으로 인하여 혐기소화 효율이 미국 등 선진국 대비 약 54.2 %에 불과한 실정이다. 환경부는 바이오가스화 효율을 증진하고 하수슬러지를 바이오매스로 활용하기 위하여 2010년부터 전국적으로 에너지자립화 사업을 추진하였다. 특히 혐기소화조가 미설치된 하수처리장을 대상으로 음식물류폐기물과 병합소화시 연계 하수처리장의 유입 수질 등을 사전에 검토한 후 신규 소화조를 건설을 진행하고 있다. 하수슬러지 단독 및 병합처리 시설의 혐기소화조 내부 유출액에 대한 최우점 미생물 종을 분석하고 바이오가스화 시설의 주요 운전인자(유기물부하율, 메탄가스 발생량, C/N 비 등) 간의 정준상관분석을 실시하였다. 하수슬러지 단독 및 병합처리 시설의 상관관계 분포가 뚜렷이 구분되었으며, 메탄가스 생성율은 음폐수의 영향으로 VFAs, C/N비, VS/TS 등과 비례관계를 보임과 동시에 Mesotoga, Methanosaeta 미생물 군이 우점하는 경향을 보였다. 또한 하수슬러지 단독처리 바이오가스화 시설의 혐기소화조에서는 Copro-thermobacter, Methanosarcina 등의 미생물 분포가 높게 나타났다.

산업의 발달과 생활수준이 높아짐에 따라 에너지의 사용량이 증가되고 있는데 이중 대부분은 화석연료에 의해 충족되고 있다. 하지만 화석연료의 한계성과 온실가스 발생 등의 환경문제로 인해 새로운 대체 에너지 연구개발에 대한 관심이 크다. 바이오매스는 탄소중립이 가능한 친환경적 재생에너지 이다. 특히, 하수처리장에서 발생량이 지속적으로 증가되고 처리의 어려움을 가지고 있는 하수 슬러지 폐기물은 청정에너지와 자원으로 전환이 가능한 바이오매스이다. 이러한 바이오매스 폐기물의 전환기술 중 현재 관심을 가지고 연구가 진행되고 있는 것은 하수 슬러지를 열분해 또는 가스화 해서 바이오 가스, 바이오 오일, 슬러지 촤(sludge char)의 에너지를 생산하는 방법이다. 최근에는 마이크로 웨이브 가열방식에 의한 바이오매스 열적처리 방식에 대한 연구가 진행되고 있다. 마이크로웨이브 방식은 기존의 외부 열풍가열 방식과 달리 마이크로파가 직접 바이오 셀 내부로 침투해 물질분자와 원자 등을 진동시켜 직접 열을 발생시키는 유전체 가열이 진행된다. 이로 인해 기존의 가열방식에 비해 가열효율(heating efficiency)과 가열 율(heating rate)이 높고 이로 인해 가열시간이 단축되는 장점을 가지고 있다. 본 연구에서는 슬러지 폐기물을 바이오매스-CCS 기술(biomass-CCS technology)적용을 위한 새로운 형태의 마이크로웨이브 열적처리 기술을 개발하고자 한다. 이를 위해 마이크로웨이브 유전체가열 특성을 활용하여 탈수 슬러지를 건조-가스화 연속 일체형으로 진행하는 에너지 전환 특성을 파악하였다. 가스화 실험의 경우는 연소 전 포집 기술의 이산화탄소 분리공정에서 포집된 것을 활용하는 측면에서 이산화탄소 가스화에 대한 연구를 수행하였다. 이산화탄소 가스화 시 생성물은 가스, 촤, 타르인데 그 중 가스가 가장 많이 생성되고 잔류 탄화물인 슬러지 촤(sludge char) 그리고 중질 탄화수소인 타르의 순으로 생성되었다. 가연성 생성가스(producer gas)는 주로 수소와 일산화탄소가 생성되었고 일부 메탄과 탄화수소(THCs: C2H4,C2H6,C3H8)포함되었다.

This paper is containing two study. The one is a land treatment of sewage sludge reduction through the indirect heating method and the other verifies conversion possibility of sludge organic matter to auxiliary fuel, steel thermal insulation material, byproduct fertilizer compost and find the suitable recycling method for J city. It was confirmed that about 88 percent of weight reduction for transportation efficiency and method verification. The analysis result of the carbonized product component showed the average low heating value of about 2,850 kcal and the moisture content of 1.4% which means the sludge is suitable as a fuel.