손준익 Jun Ik Son , 김기헌 Ki Heon Kim , 홍용희 Yong Hee Hong , 황동건 Dong Gun Hwang , 오길종 Gil Jong Oh

DOI:10.9786/kswm.2014.31.6.591

Abstract

In this study those currently operating pyrolysis oil plant were selected for the investigation. The yield of the oil and fuel was assessed for its use as fuel and the char component analysis, and the reaction time to collect contaminants collected and analyzed. As the result, about 40% of the oil was yielded and oil could be used as an alternative fuel. Char’s leaching test analysis result was satisfied with the landfill standard. And emission of Dioxin and pollutants was analyzed. The highest concentration of dioxin was 0.7347 ng I-TEQ/Sm3. The result satisfied the requirement however the emission concentration was changed depending on the input Fuel. Therefore the appropriate pollution control facility should be required.

Key Words

Pyrolysis, Oil, Char

전태완 Tae Wan Jeon , 정미정 Mi Jeong Jeong , 이지영 Ji Young Lee , 강영렬 Young Yeul Kang , 박종은 Jong Eun Park , 홍수연 Soo Hyun Hong , 정성경 Seong Kyeong Jeong , 신선경 Sun Kyoung Shin

DOI:10.9786/kswm.2014.31.6.598

Abstract

For management of hazardous waste, the Ministry of Environment regulates fewer items and has fewer test methods for toxic chemicals than developed countries. Regulated items should be expanded in order to strengthen the management of hazardous waste and comply with international trends. For conducting to quantify the cost and value of the expansion, we estimated the amount of toxic waste and evaluated applicability and economic effects of the expansion of regulated items to the industry. Through a survey of domestic and foreign studies, we reviewed the substances (e.g. F and Ni) that are regulated as hazardous chemicals and planed a road-map for gradual expansion of regulated items. The analysis of treatment cost had been focused on the result of leachate and total content analysis of regulated 7 inorganic materials (Hg, Pb, Cd, As, Cu, Cr+6, and CN) and unregulated 8 inorganic metals (F, Ni, Zn, Se, Sb, Ba, Be, V), and also total content analysis of unregulated 4 organic materials (PAHs, PCDD/DFs, HCB, and PCBs) in Korea. With the result of content concentration of unregulated 8 inorganic metals, we could estimate that they were discharged about 4.644 million ton/year from industries in Korea. Also, The amount of waste from oil refining, steel, and casting factory was more than 50% of total generated waste in Korea.

Key Words

Hazardous waste, Regulated items, Inorganic metals

임대원 Dea Won Lim , 최병수 Byeong Soo Choi , 김진우 Jin Woo Kim , 김슬기 Seul Ki Kim , 김태석 Tea Seok Kim , Jeeban Poudel , 권우택 Woo Teck Kwon , 오세천 Sea Cheon Oh

DOI:10.9786/kswm.2014.31.6.609

Abstract

In this work, the separation characteristics of CO2 from CO2 and CH4 mixed gas was studied using pressure swing adsorption (PSA) process. Zeolite 13X was used as an adsorbent to adsorb CO2 from gaseous stream in a fixed-bed of adsorbent. The adsorption experiments were performed with various gas flow rates, adsorption pressures and temperatures. The deactivation model was used to analyze the adsorption kinetics of CO2 using the experimental breakthrough data. From this work, it was found that the activation energies of adsorption and deactivation were 29.15 and 13.0 kJ/mol, respectively. And the experimental breakthrough curves were agree very well with the adsorption isotherm models based on Freundlich equation.

Key Words

Adsorption, PSA, CO2, Zeolite, Adsorption Kinetics

이관호 Kwan Ho Lee

DOI:10.9786/kswm.2014.31.6.616

Abstract

In this study, the field construction with the prefabricated lightweight plastic foundation using recycled plastic for sewage pipeline and triple wall PE sewer pipe was carried out to verify the construction workability of prefabricated plastic foundation and deformation resistance potential of triple wall PE sewer pipe. The construction procedure in field was followed the KS standard. The measured vertical deformations of PE pipe are average 2.35 mm which means around 1% of deformation for 300 mm diameter of PE pipe. Judging from the type of foundation, the use of plastic foundation (Case B & Case C) showed lower deformation due to differential settlement than that of sand bedding foundation. Especially, the plastic foundation made a relatively uniform deformation of PE pipe. However, the sand foundation represented the non-uniform deformation of PE pipe.

Key Words

Pipe deformation, Triple wall PE sewer pipe, Prefabricated lightweight plastic foundation, Recycled plastic, Field construction

김석환 Seok Hwan Kim , 임병란 Byung Ran Lim , 이수구 Soo Koo Lee

DOI:10.9786/kswm.2014.31.6.623

Abstract

This study was performed to evaluate the drying characteristics of food waste in oil vacuum evaporation system with drying conditions and composition of food waste. The food waste was collected and separated into 4 categories such as vegetables, fruits, grain (rice), meats and others. which composition were 41.9%, 26.7%, 2.8%, 25.5% and 0.4%, respectively. Each food waste separated was dried and compared its characteristics in the same condition of vacuum pressure (.450 mmHg), temperature (110oC) and mixing ratio (oil : food waste = 1 : 1) for 90 min of drying period. The experimental results showed that the moisture contents of dried vegetables, fruits and meats were less than 10%. However the grain was hard to be dried which moisture content was much high as 24.5%. This high value of the grain was thought due to the viscosity of grain which prohibit oil penetration and water vaporization during drying process. In order to compare drying characteristics with operating parameters, vacuum pressure, temperature and mixing oil type were changed. The operating temperature and vacuum pressure were major sensitive parameters. As the temperature increase and the pressure lower, the drying rate of food waste was increased and its efficiency was also improved. Especially, the moisturecontent of dried food waste was lower than 5% which was satisfied SRF standard 10% at the temperature over 110oC. Compared the effect of mixing oil type, waste cooking oil was more effective than refined oil in viewpoint of drying efficiency. However, there is no difference of drying efficiency between fresh and waste cooking oil.

Key Words

Food waste, Vacuum, Evaporation, Drying characteristics

이동진 Dong Jin Lee , 정진 Jin Chung , 강준구 Jun Gu Kang , 김영란 Young Lan Kim , 황동건 Dong Gun Hwang , 이성수 Sung Soo Lee , 김기헌 Ki Hean Kim , 이수영 Su Young Lee

DOI:10.9786/kswm.2014.31.6.629

Abstract

In this study the production of methane gas and the removal efficiency of nutrients in the anaerobic co-digestion facilities with food waste/food waste leachate (FWL), animal manure and food waste leachate (A-MIX), and sewage sludge and food waste leachate (S-MIX) were investigated. The average amount of the theoretical methane production was 578.4 CH4·L/kg·VSin from the anaerobic digestion facilities with FWL, 606.0 CH4·L/kg·VSin from those with A-MIX and 570.0 CH4·L/kg·VSin from those with S-MIX, respectively. The amount of the practical methane production was 350.7 CH4·L/ kg·VSin from the anaerobic digestion facilities with FWL, 379.5 CH4·L/kg·VSin from those with A-MIX and 348.8 CH4·L/ kg·VSin from those with S-MIX, respectively. The nutrient compositions of FWL were 3.2 g/100 g for carbohydrates, 1.8 g/100 g for proteins and 1.9 g/100 g for lipids. The nutrient compositions of A-MIX were 0.4 g/100 g for carbohydrates, 2.55 g/100 g for proteins 0.4 g/100 g and 0.7 g/100 g for lipids, respectively. The nutrient compositions of S-MIX were 0.4 g/100 g for carbohydrates, 2.4 g/100 g for proteins 1.6 g/100 g and 0.4 g/100 g for lipids, respectively. The removal ratio of carbohydrate was very high over 75% in all facilities and that of lipid was very low below 25%.

Key Words

Food waste leachate, Methanegas production, Nutrients removal

성진호 Jin Ho Sung , 서용칠 Yong Chil Seo , 장하나 Ha Na Jang , 백승기 Seung Ki Back , 정법묵 Bup Mook Jeong , 김정훈 Jeong Hun Kim , 정승재 Seung Jae Jung , 조윤탁 Yun Tak Cho

DOI:10.9786/kswm.2014.31.6.638

Abstract

Fossil fuel combustion generates large amount of green house gas and it was considered major emission source causing global warming. For reducing green house gas, renewable energy resources have been emerged as an alternative energy. Among those resources, waste has been considered major resource as one of renewable energy, but it has been not utilized sufficiently. In Korea, there are lots of efforts to utilize sewage sludge as one of renewable energy resources due to waste to energy project of government. In this paper, sewage sludge was utilized as main fuel in order to recover heat energy source using oxy-fuel combustion in 30 KWth circulating fluidized bed (CFB) pilot plant. Firstly, basic characteristics of sewage sludge were analyzed and fuel feed rate was calculated by stoichiometry oxygen demand. For producing 30 kw thermal energy in pilot plant, the feeding rate of sewage sludge was calculated as 13 kg/hr. In oxy-fuel combustion, oxygen injection rate was ranged from 21% to 40%. Fluidized material was more suitably circulated in which the rate of U/Umf was calculated as 8 at 800oC. Secondly, Temperature and pressure gradients in circulation fluidized bed were compared in case of oxy and air combustion. Temperature gradients was more uniformly depicted in case of 25% oxygen injection when the value of excess oxygen was injected as 1.37. Combustion efficiency was greatest at the condition of 25% oxygen injection rate. Also, the flue gas temperature was the highest at the condition of 25% oxygen injection rate. Lastly, combustion efficiency was presented in case of oxy and air combustion. Combustion efficiency was increased to 99.39% in case of 25% oxygen injection rate. In flue-gas composition from oxy-fuel combustion, nitrogen oxide was ranged from 47 ppm to 73 ppm, and sulfur dioxide was ranged from 460 ppm to 645 ppm.

Key Words

Sewage sludge, Oxy-fuel combustion, Circulating fluidized bed, Combustion efficiency, Flue gas composition

이승희 Seung Whee Rhee

DOI:10.9786/kswm.2014.31.6.646

Abstract

Most spent foundry sand (SFS) is disposed in waste containment facilities; only 41.4% beneficially reused in recycling. In foreign countries, some spent foundry sand is finding uses in highway bases and retaining structures, asphalt concrete, and pavement bases. However, limited information is available on the use of SFS as a component in the base or subbase layers of pavements. Large volumes of SFS can be used in roadway construction, so this information is very important. In this study, the geotechnical properties of SFS amended road base material such as particle size, turbidity, and permeability were estimated to decided the optimal conditions in thermal stabilization. At the optimal conditions, abrasion test and California bearing ratio (CBR) test were conducted to evaluate the degree of qualification for the standard of subbase layers of pavement. Also, the hazardous characteristics of SFS were evaluated by Korea extraction test (KET) and toxicity characteristic leaching procedure (TCLP). It was realized that SFS can be used as auxiliary material in pavement subbase when particle size of SFS was amended by mixing with another pavement materials.

Key Words

Spent foundry sand, Auxiliary material, Stabilization, Pavement subbase

조재범 Jae Beom Cho , 최한나 Han Na Choi , 조은하 Eun Ha Cho , 김병수 Byung Soo Kim , 최미영 Mi Young Choi , 박병곤 Byung Gon Park

DOI:10.9786/kswm.2014.31.6.654

Abstract

The objectives of this research was to evaluate the anaerobic digestibility of waste actizvated sludge (WAS) and waste beverages in beverages manufacturing industry using BMP test under various conditions. Also, the effects of physical (ultrasonic) and biological (lactobacillus) solubilization process on anaerobic digestibility of WAS were thoroughly studied. The soluble chemical oxygen demand (SCODCr)/total chemical oxygen demand (TCODCr) ratio of WAS was 0.15 but the SCODCr/TCODCr ratio after solubilization was increased 17.5% by ultrasonic, 18.8% by lactobacillus respectively. The results of BMP test, methane gas productivity as mixing ratio of WAS and waste beverages were 156 ml CH4/gCODCr, 164 ml CH4/gCODCr and 182 ml CH4/g CODCr, respectively 9 : 1, 8 : 2, 7 : 3 before the solubilization of WAS. As the mixing ratio of waste beverages increase, VFAs concentration and methane productivity was increased. Also, methane gas productivity as mixing ratio after the solubilization of WAS using ultrasonic and lactobacillus was increased 3.3 ~ 11.3%, 11.1 ~ 15.2% respectively. From the results, it was judged that anaerobic digestion using WAS and waste beverages could be feasible.

Key Words

Biogas, BMP test, Waste activated sludge, Waste beverages

문종욱 Jong Wook Moon , 김병윤 Byung Yun Kim

DOI:10.9786/kswm.2014.31.6.662

Abstract

Recently, in our country has been heightened awareness of the performance of non-combustible construction materials and eco-friendly. In addition, bottom ash can be used as a high-value, but it is a situation that is buried. Therefore, the basic experimental study results on the development possibility of eco-friendly nonflammable floor finishing materials using the bottom ash, which is an industrial byproduct, are as follows: (1) As a test result of the compressive strength of mortar conducted to review the use possibility of bottom ash as a floor finishing material, the standard mix that did not use bottom ash showed 31.3 MPa, a 25% replacement mix showed 33.7 MPa and a 50% replacement mix showed 33.6 MPa. Consequently, higher results of the compressive strength of mortar were demonstrated up to the 50% replacement mix, compared to the standard mix. (2) As a flow test result by addition of superplasticizer, the flow was 215 mm in the 0.2% added mix, and 253 mm in the 0.4% added mix. However, material separation was confirmed in the case of the 0.4% added mix. Therefore, the addition meeting 190 mm set forth in the KS F 4041 was 0.2%. (3) As a result of bond strength test to review bond strength with concrete structure, it was 1.26 MPa in case polymer powdercontent was 2%, except for 1.02 MPa of basic mix, and it was 1.75 MPa in the case of 4%, and all these met1.2 MPa and more of bond strength set forth in the KS. (4) As a result of a wear resistance experiment conducted to review the use possibility as a floor finishing material for parking lot, the mix meeting 0.15 mg/mm2 or less of wear resistance set forth in the KS F 4041 was the case of 4% of polymer powder addition, which showed 0.13 mg/mm2.

Key Words

Bottom ash, Flooring, Self leveling mortar, Underground parking

송우영 Woo Young Song , 김혜숙 Hey Suk Kim , 신미수 Mi Soo Shin , 장동순 Dong Soon Jang , 이재구 Jae Goo Lee

DOI:10.9786/kswm.2014.31.6.671

Abstract

In order to ensure the high carbon conversion in a short residence time in a coal slurry entrained gasifier, the objective of this study lies in to investigate the effect of important variables to influence on the complex reacting flow and thereby to clarify the physical feature occurring inside the gasifier using a comprehensive gasifier computer program. To this end, the gasification process of a 1.0 ton/day gasifier is numerically modeled using the code of Fluent and systematically investigated with the change of major design and operation parameters. Special emphasis is given on the effect of the particle size distribution on the gasification process, since it is associated with various length and time scales via multiphase and with complex reacting flows. Three different particle sizes are tested for a given coal mass flow rate, the first is 70 μm mean diameter with Rosin-Rammler distribution based on the actual measurement. But in the other two cases two uniform mean particle diameters are employed, that is, very fine 1 μm and 70 μm with mean diameter itself. The calculation results of these three cases show quite different flow pattern, temperature and reacting flows probably caused by the different particle trajectory as well as reaction rate. However, the results obtained can be explained in a consistent manner with particle size. Especially, it is noted that the presence of coal particle, the diameter of which is larger than that of mean diameter of Rosin-Rammler distribution, shows a significantly retarded gasification reaction in a gasifier, even if its mass fraction is less than 50%.

Key Words

Coal slurry entrained gasifier, CFD model, Particle size distribution

박용규 Yong Kyu Park , 윤기원 Ki Won Yoon

DOI:10.9786/kswm.2014.31.6.681

Abstract

In this study, from the material properties of the aggregates into the actual applications were evaluated for utilizing the air-cooled blast furnace slag as the coarse aggregates (SG) in PHC piles. The physical and chemical characters of the SG were satisfied the standards presented in KS F 2544 for concrete blast furnace slag aggregates. And it was satisfied the environmental-factor-evaluation, including the soluble, heavy metal elution and total mercury content, and etc. In case the non-washed type SG is used, the S/A ratio adjustment according to micro-powder of the aggregate surface and chemical admixture adjustment are needed in order to satisfy the aimed material properties. As the replacement ratio of SG increased, the manifestation rate of compressive strength of the PHC piles was decreased. Particularly, in case non-washing type SG, the manifestation rate more decreased. Therefore, the elimination of the pop-out materials and cleaning process are necessary for the production process for using the SG as coarse aggregates of PHC Piles

Key Words

Blast Furnace Air-Cooled Slag, Coarse Aggregate, PHC Pile

류선영 Sun Young Ryu

DOI:10.9786/kswm.2014.31.6.689

Abstract

A pink-colored china body has a feeling of warmth was manufactured using basalt sludge and white clay. Mechanical properties and microstructure of fired bodies were investigated by XRD, SEM and UV spectroscopic. The china body containing 60wt% of basalt sludge fired at 1050oC for 30 min showed a bulk density of 1.76 g/cm3, water absorption of 16.25% and bending strength of 5.25 N/mm2, and value of CIE L*, a*, b* is 67.64, 7.82, 8.17 respectively. A phase of Piustite and maghemite included in basalt sludge transferred to phase of Hematite with a pink color under oxydation atmosphere, over 1,000oC. It appeared black when the firing temperature was higher than 1,100oC.

Key Words

China body, Basalt sludge, Hematite phase, Pink color

윤석표 Seok Pyo Yoon

DOI:10.9786/kswm.2014.31.6.695

Abstract

In this study, to understand the current status of solid waste management in China, the author presented generation and treatment status of municipal solid waste in China, and the composition of municipal solid waste in the Southern China. Also following important definition and control measures for solid waste management in China were reviewed. (1) The definition of solid waste, (2) Solid waste identification guide, (3) Leaching test for the determination of hazardous waste, (4) Standard for pollution control on the landfill site of municipal solid waste, (5) Municipal solid waste landfill harmless evaluation criteria, and (6) Twelve Five national municipal solid waste treatment facilities construction plan.

Key Words

China, Waste management, Definition of waste, Identification, Leaching test