• Title/Summary/Keyword: oyster shell

Search Result 395, Processing Time 0.029 seconds

Evaluation of SO2 Absorption Efficiency for Calcined Oyster Shell Slurry Using a Simulated Spray Type-flue Gas Desulfurization (FGD) System: A Comparative Study with Limestone Slurry (모사 Spray Type 배연탈황설비를 이용한 소성패각 슬러리의 SO2 흡수능 평가: 석회석과의 비교연구)

  • Kim, Seok-Hwi;Hong, Bum-Uh;Lee, Jin-Won;Cha, Wang-Seok;Kim, Kangjoo;Moon, Bo-Kyung
    • Economic and Environmental Geology
    • /
    • v.52 no.2
    • /
    • pp.119-128
    • /
    • 2019
  • About 300,000 tones of oyster shell are annually produced in Korea and, thus, a massive recycling plan is required. Many desulfurizing studies using oyster shells with chemical composition of $CaCO_3$ have been performed so far; however, most of them have focused on dry desulfurization. This study investigates the possibility of using oyster shells for wet desulfurization after calcination. For this, a simulated wet desulfurization facility of spray type was devised and compared the SOx-stripping characteristics of calcined oyster shell with those of limestone. The calcined oyster shell slurry indicate a better desulfurizability than the slurries of raw shell or limestone because the oyster shell transformed to a more reactive phase ($Ca(OH)_2$) by the calcination and hydration. Because of this reason, when the calcined oyster shell slurries were used, the reaction residue showed the higher gypsum ($CaSO_4{\cdot}2H_2O$) contents than any other cases. In the continuous desulfurization experiments, calcined oyster shell slurry showed a wider pH variation than limestone or raw oyster shell slurries, another clear indication of high reactivity of calcined oyster shells for $SO_2$ absorption. Our study also shows that the efficiency of wet desulfurization can be improved by the use of calcined oyster shells.

Stabilizing Capability of Oyster Shell Binder for Soft Ground Treatment (표층/심층혼합처리용 굴패각 고화재의 고화성능 평가)

  • Yoon, Gil-Lim;Kim, Byung-Tak
    • Journal of the Korean Geotechnical Society
    • /
    • v.22 no.11
    • /
    • pp.143-149
    • /
    • 2006
  • An experimental study was carried out to investigate the stabilizing capability of oyster shell binder, which was developed using waste oyster shell inducing environmental pollutions by piling up out at the open or the temporary reclamation. The purpose of this paper is to compare stabilinzing capability of oyster shell binder and cement binder with treated soils. For this, a series of compressive laboratory tests were peformed to evaluate strength characteristics of treated soils by both oyster shell binder and cement binder with varing water content of dredged soils, different mixing rates of binder and curing days. Based on test results, eco-friendly binder manufactured by oyster shells showed more stabilizing capacity than cement binder and is estimated as good resource materials for soft soil improvements.

The Use of Oyster Shell Powders for Water Quality Improvement of Lakes by Algal Blooms Removal

  • Huh, Jae-Hoon;Choi, Young-Hoon;Lee, Hyun-Jae;Choi, Woo Jeong;Ramakrishna, Chilakala;Lee, Hyoung-Woo;Lee, Shin-Haeng;Ahn, Ji-Whan
    • Journal of the Korean Ceramic Society
    • /
    • v.53 no.1
    • /
    • pp.1-6
    • /
    • 2016
  • In this year, Koreans have a shortage in agricultural and drinking water due to severe algal blooms generated in major lakes. Waste oyster shells were obtained from temporary storage near the workplace at which oysters were separated from their shells. Heating ($1000^{\circ}C$ for 1 h in air) was employed to convert raw oyster shell powders into calcium oxide powders that reacted efficiently with phosphorus and nitrogen to remove algal blooms from eutrophicated wastewater. As the dispersed amount of heated oyster shell powders was increased, water clarity and visual light penetration were improved. Coagulation, precipitation and carbonation process of the heated oyster shell powders in a water purifier facilitated removal of eutrophication nutrient such as phosphorus and nitrogen, which is both beneficial and economically viable. $CO_2$ implantation by carbonation treatment not only produced thermodynamically stable CaO in oyster shells to derive precipitated calcium carbonate (PCC) but also accelerated algal removal by activation of coagulation and precipitation process. The use of oyster shell powders led to a mean reduction of 97% in total phosphate (T-P), a mean reduction of 91% in total nitrogen (T-N) and a maximum reduction of 51% in chemical oxygen demand (COD), compared with the total pollutant load of raw algal solution. Remarkable water quality improvement of algal removal by heated oyster shell powders and PCC carbonation treatment will allow utilization as water resources to agricultural or industrial use.

Effect of Oyster Shell Addition on the Dissolved Air Flotation and Sedimentation of Bulking Sludge (팽화슬러지의 용존공기부상과 침전에 미치는 굴패각 첨가의 영향)

  • Kim, Dong-Seog;Park, Young-Seek
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.29 no.1
    • /
    • pp.82-88
    • /
    • 2007
  • The objective of this study is to examine the effect of the waste oyster shell powder as the addition agent in bulking sludge thickening of paper manufacturing plant using DAF(Dissolved Air Flotation) and gravitational sedimentation. The effect of parameters such as dosage and size distribution of oyster shell were examined. The results showed that the optimum dosage of mixed oyster shell(size range : $\sim250{\mu}m$) was 0.8 g/L. The oyster shell addition of 5.0 g/L in sedimentation process was increased thickening concentration of 3.25 times. When 5.0 g/L of oyster shell was added in DAF process, water content of sludge was decreased from 95.5% to 82.7% in dewatering process using Buchner funnel test device. When size of oyster shell was divided four ranges($\sim53{\mu}m$, $53\sim106{\mu}m$, $106\sim150{\mu}m$, $150\sim250{\mu}m$), optimum size range for the flotation and dewatering was $53\sim106{\mu}m$.

Quality Characteristics and Storage Properties of Gat Kimchi added with Oyster Shell Powder and Salicornia herbacea Powder (굴 패각 가루와 함초 가루를 첨가하여 제조한 갓김치의 품질특성과 저장성)

  • Jung, Bok-Mi;Jung, Sun-Jin;Kim, Eun-Sil
    • Korean journal of food and cookery science
    • /
    • v.26 no.2
    • /
    • pp.188-197
    • /
    • 2010
  • In this study, the quality characteristics and storage properties of gat kimchi added with oyster shell powder and Salicornia herbacea powder were investigated during a storage time of 80 days at $5^{\circ}C$. After storage for 80 days, the average calcium contents were significantly higher in the kimchi containing the oyster shell powder and Salicornia herbacea powder than the control. In addition, the average hardness value was significantly higher in the OS4 group(oyster shell powder at 4% and Salicornia herbacea powder at 2%) than the control group, as well as the OS10 group(oyster shell powder at 10% and Salicornia herbacea powder at 2%) during storage for 80 days. The hunter b value of the OS4 group was significantly lower than the control group. During fermentation, gat kimchi containing the oyster shell powder and Salicornia herbacea powder had a higher pH and a lower acidity value than the control group. In terms of sensory evaluation, there were no significant differences between the control and calcium-added kimchi during fermentation. After 40 days of storage, the OS4 group showed a lower total viable count, as well as lower lactic acid bacteria, yeast and E. coli, as compared with the control and OS10 groups. Based on the microbial load, the gat kimchi containing the oyster shell powder showed limitations in terms of shelf life.

Study on the Heat and Mass Transfer Characteristics of Oyster Shell Flowing through the Bundle of Heating Pipes (가열원관군 주위를 유동하는 굴패각의 탈착과정에 대한 열 및 물질전달에 관한 연구)

  • Kim, Myoung-Jun
    • Journal of Power System Engineering
    • /
    • v.17 no.3
    • /
    • pp.28-34
    • /
    • 2013
  • This study is experimentally performed for using the oyster shell as a desiccant in the fluidized bed with bundle of heating pipe. The test material is oyster shell from fishery wastes which can use without costs. The main parameters of experiment are inlet air temperature, velocity of inlet air and heat flux of heating pipes. Also the geometry of heating pipe is treated as important parameter. From this study, the effect of inlet air temperature and input heat flux have much affect to increase the heat and mass transfer. On the other hand, the effect of inlet air velocity has less affect to increase the heat and mass transfer. And it is clarified that the oyster shell has sufficient probability for using as a desiccant in air-conditioning system.

A Strength Properties According to Water cement ratio using Oyster shell as Aggregate (굴 패각을 잔골재로 사용한 모르타르의 물시멘트비에 따른 강도특성)

  • Jung, Ui-In;Choi, In-Kwon;Heo, Min-Hoe;Kim, Bong-Joo;Won, Chul-Hee;Choi, Ho-Rim
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2016.10a
    • /
    • pp.154-155
    • /
    • 2016
  • Oyster shell is light weighted and its strength characteristic is similar to sand. So we produced mortar test piece using grounded oyster shell powder under 0.5mm, which is a standard of fine aggregate, and reviewed strength properties according to water cement ratio. In our test, we used two kinds of oyster shell particles: below 0.6mm and 1.2~2.5mm. Water cement ratio is varied 40% to 100% and we found that flexural strength and compressive strength are decreased in higher water cement ratio.

  • PDF

A Study on Size Distribution of Oyster Shell According to the Change of Inverter Cutter Mill Speed (커터 밀 인버터의 속도변화에 따른 굴 패각의 입도분포에 관한 연구)

  • Jung, Ui-In;Heo, Min-Hoe;Yu, Nam-Gyu;Kim, Bong-Joo;Won, Chul-Hee;Park, Jung-Hun
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2016.10a
    • /
    • pp.98-99
    • /
    • 2016
  • Oyster shell is light weighted and its strength characteristic is similar to sand so we have reviewed to find its suitability of aggregate. Therefore we found fineness modulus and size distribution of oyster shell by grinding it with inverter cutter mill varying inverter speed and screening size. In our test, the fineness modulus has tendency of decrease in higher speed and tendency of increase in bigger diameter of screening size. 5~2.5mm, 2.5~1.2mm, 1.2~0.6mm, and below 0.6mm of oyster shell particle size could be used in further test for suitability of aggregate.

  • PDF

Extraction of Precipitated Calcium Carbonate from Oyster Shell waste and Its Applications

  • Ramakrishna, Chilakala;Thenepalli, Thriveni;Nam, Seong Young;Kim, Chunsik;Ahn, Ji Whan
    • Journal of Energy Engineering
    • /
    • v.27 no.1
    • /
    • pp.51-58
    • /
    • 2018
  • In this paper, we reported that the influence of advanced functional mineral filler calcium carbonate ($CaCO_3$) extracted from oyster shell waste, which are rich mineral sources of $CaCO_3$. Oyster Shells, available in abundance, have no eminent use and are commonly regarded as waste. Their improper disposal causes a significant level of environmental concern and also results in a waste of natural resources. Recycling shell waste could potentially eliminate the disposal problem, and also turn an otherwise useless waste into high value added products. Oyster shell waste calcination process to produce pure lime (CaO) which have good anti-microbial property for waste water treatment and then focuses on its current applications to treat the coffee waste and its effluents for biological treatment and utilization as a fertilizers.

A Study on the Flexural and Compressive Strength of Mortar Mixed with Oyster Shell Powder and Egg Shell Powder (굴 패각 분말과 계란 껍데기 분말을 혼합한 모르타르의 휨·압축강도에 관한 연구)

  • Kim, Han-Nah;Shin, Dong Uk;Shin, Joung Hyeon;Hong, Sang Hun;Jung, Ui In;Kim, Bong Joo
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2020.11a
    • /
    • pp.94-95
    • /
    • 2020
  • Oyster shells are characterized by coarse and coarse grains, but similar in strength to sand, and egg shells are fine grains but weak in strength. In terms of supply and demand of raw materials, oyster shells can be supplied only in limited periods and regions in winter and south coast of the year, but egg shells have the advantage of being able to supply and supply nationwide 365 days. This study aims to study the change in strength characteristics by mixing oyster shell powder and egg shell powder with the same particle size and mixing up to 150%. The conclusions of the flexural and compressive strength tests of mortar mixed with oyster shell powder and egg shell powder are as follows. The 7-day flexural and compressive strength with ESP added and the 3-day flexural and compressive strength with OSP added were similar, which is thought to be because the strength of OSP is higher than that of ESP.

  • PDF