• Journal of Korean Society of Environmental Engineers
• /
• v.38 no.10
• /
• pp.574-579
• /
• 2016

This study assessed feasibility of making granular fertilizer with fly ash from a sewage sludge incinerator in Korea. Composition, characteristics, strength, and heavy metal contents of the granular fertilizers were investigated. Due to its high contents of phosphorus, fly ash from a sewage sludge incinerator could be used to make fertilizers. Granulation rates (2-4 mm granules) over 80% could be achieved as the fly ash contents were 15% or less of the fertilizer. Leaching tests of the fertilizers, based upon the Korean Standard Methods for Solid Wastes, showed the concentrations of heavy metals less than the risk limits. However, contents analysis of the fertilizers, based upon the Korean Standard Methods for Soils, experienced higher levels of heavy metals than the risk limits as the fly ash content exceeded 7% of the fertilizer. Thus, the fly ash needs to be added less than 7% of the fertilizer if there is no pretreatment to remove heavy metals.

• Resources Recycling
• /
• v.14 no.1
• /
• pp.39-46
• /
• 2005

A solid-state high power torch with inter-electrode insert (IEI) was developed to treat solid waste (for example, incinerated ash), and it's operation characteristics were obtained in the plasma facility test for waste treatment. According to torch test from this study, at the non-transferred mode voltage is increased by gas volume proportionally, and at the transferred mode it is not affected to voltage change. Especially arc voltage is sustained stable at the range of 10% of total Fe in slag. In addition, Electrical conductivity is 0.05~0.25${\Omega}^{-1}cm^{-1}$, torch efficiency is 75~85% and Erosion rate is 2${\times}10^{-6}~6{\times}10^{-6}$ kg/s.

• Journal of Korean Society of Environmental Engineers
• /
• v.30 no.5
• /
• pp.560-566
• /
• 2008

In this paper, the solidification behaviour and compressive strength of fly ash, cement, and waste stone powder were studied each separately and with addition of each in different proportions. And also, we assessed stabilizing ability of waste stone powder in cement which was added in fly ash. The particle size of waste stone powder was found smaller than the fly ash and cement particle sizes. Moreover, when mixing all(fly ash, cement, and waste stone powder) showed distinctive crystal structure, and improved stiffness. In case of mixing fly ash, cement and waste stone powder in different proportions, the compressive strength was exceeded to the predicted compressive strength of 10 kgf/cm$^2$. The XRD analysis showed high contents of CaO in fly ash and SiO$_2$ in case of waste stone powder sample. Heavy metal emission experiment showed the 3mg/L of Pb after 14 days of mixing 150 kg/m$^3$ of cement with the 80$\sim$100 kg/m$^3$ of waste stone powder, which is fulfilling the National Waste Management Policy.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2005.11a
• /
• pp.773-776
• /
• 2005

MSWI ash is the residue from waste combustion processes at temperature between $850^{\circ}C\;and\;1000^{\circ}C$. And the main components of MSWI ash are $SiO_2,\;CaO\;and\;Al_2O_3$. The aim of this study is to find a way to useful application of MSWI ash(after treatment) as a structural material and to investigates the hydraulic activity, compressive strength development, composition variation of such chemicallyi-activated MSWI ashes concrete. And it was found that early cement hydration, followed by the breakdown and dissolving of the MSWI-ashes, enhanced the formation of calcium silicate hydrates(C-S-H), The XRD and SEM-EDS results indicate that, both the hydration degree and strength development are closely connected with a curing condition and a chemically-activator. Compressive strengths with values in the 40.5MFa were obtained after curing the activated MSWI ashes with NaOH+water glass at $90^{\circ}C$.

• Journal of the Korean Ceramic Society
• /
• v.37 no.8
• /
• pp.768-773
• /
• 2000

Alnite clinker, which is based on CaO-SiO2-CaCl2 system, was synthesized by recycling Cl-containing waste, and its hydraulic properties were onvestigated. Alinite coinkers with two different chemical compositions were burned for 10∼30 minutes in the range of temperature, 1350∼1450$^{\circ}C$. The microstructures of those clinkers were characterized by powder X-ray diiffracuion analysis, optical microscope, and scanning electronic microscope and heat of hydration of alinite cements which was measured in order to investigate hydraulic properties. X-ray analysis shwoed that f-CaO in both clinkers with different compositions significantly was decreased with transforming C2S(belite) to C3S(alite). From the results of microscopy and scanning electron microscopy(SEM), crystal of synthesized alite(C3S) was larger and better crystallinity than that of ordinary portland cement.

• Journal of Environmental Science International
• /
• v.11 no.10
• /
• pp.1109-1116
• /
• 2002

This study analyzed concentrations of volatile organic compounds (VOCs) produced from incineration of papers at $600^{\circ}C$. The papers used in this study included A4 papers (new, printed with ink-jet, printed with carbon), newspapers (printed with bean oil, printed with a general newspaper ink), packaging box, document envelope, single-use paper cup, and cosmetic tissue. Papers were heated from room temperature upto $600^{\circ}C$ providing air inside of the electric furnace and then they were oxidized for 80 minutes at $600^{\circ}C$ maintaining the same air supply. VOCs emitted from the incineration process were sampled using an air sampling pump and bags for 160 minutes and then the components and concentrations of the VOCs were analyzed by a CC-MS. The most prominent chemical structure of the Vous identified from incineration of the papers was furans and then furans were followed by aromatics and aliphatic alkenes. About 40% of the identified VOCs contained double bonds, which have relatively a high ozone (ground level) formation potential, within their molecular structure. Also, some cancer suspecting compounds like benzene, dichlorormethane and chloroform were identified.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
• /
• 2008.04a
• /
• pp.277-280
• /
• 2008

• Proceedings of the Korea Society of Environmental Toocicology Conference
• /
• 2001.05a
• /
• pp.93-106
• /
• 2001

폐기물처리에 있어 기존 스토카 방식으로는 다이옥신 문제에 대한 근본적 해결과 발생된 소각잔재물의 처리가 곤란하다. 아울러 비산재 적정처리에 따른 운영비 부담이 증가와 매립시 잔재물중에 함유된 다이옥신등 유해물질의 미처리에 따른 매립지의 2차 오염을 유발시키고 있다. 인터넷등의 보급 확대에 따른 선진국의 환경규제내용을 실시간으로 확인할 수 있고 생활수준의 향상에 따른 Clean 환경에 대한 욕구가 증대되고있으며 환경호르몬 등의 유해물질에 대한 주민 피해의식 및 환경에 대한 주민의 요구 수준이 증대되고 있는 실정이다. (중략)

• Resources Recycling
• /
• v.15 no.5 s.73
• /
• pp.47-51
• /
• 2006

The total amount of ash generated from the municipal solid waste incineration(MSWI) in Korea was approximately 420,000 tons in 2005 including 68,000 tons of fly ash. Fly ash from MSWI generally contains high amount of CaO (upto ${\sim}50%$) due to the treatment of flue gas by spraying CaO-base materials. Currently, most of fly ash generated is finally ended up with specially designed landfill sites and only less then 20% of fly ash is recycled. In the present work, preparation of $CaCO_3$ from the MSWI ny ash was studied to promote the fly ash recycling. Fly ash obtained from the dust collector in stoker-type MSWI is used to selectively dissolve CaO by using the sugar solution. Then, $CO_2$ gas was passed through the dissolved solution to pro- duce $CaCO_3$ powder. The optimum conditions for CaO dissolution were solid content 10%, reaction time 15 minutes, sugar concentration $10{\sim}15%\;and\;pH\;10.5{\sim}11.0$. The high grade $CaCO_3$ powder was obtained and the experimental conditions are also discussed.

• Journal of the Korean Ceramic Society
• /
• v.41 no.3
• /
• pp.210-215
• /
• 2004

Porous ceramics for water-permeable paving brick was prepared by the sintering of mixed materials comprising of sewage sludge ash, waste porcelain fragment, waste glaze and low-grade clay at 1,000$^{\circ}C$ for 2 h, and the physical $.$mechanical properties, the permeability and the freeze-thaw resistance of specimens with preparation parameters were investigated. The physical mechanical properties were increased in specimens while porosity and permeability were decreased with increasing sewage sludge ash content and sintering temperature on the properties of specimens showed the opposite results. The bulk density, porosity, compressive strength and permeability (passed charge) of 30A60F specimens with 30 wt% of sewage sludge ash content, waste porcelain fragment size with 1∼2 mm and sintered at 1,000$^{\circ}C$ for 2 h were 2.17, 46.2%, 221 kgf/$\textrm{cm}^2$ and 3,150 coulombs, respectively. The permeability was increased with increasing waste porcelain fragment size, however compressive strength was decreased. The freeze-thaw resistance of 30A60F specimen with 1∼2 mm of fragment size was superior to that of the other specimens. The 30A60F specimens can be used for the water-permeable paving brick with the high permeability and adequate strength. The heavy metals included in the all specimens showed lower than the standard level.