• Corrosion Science and Technology
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• v.19 no.6
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• pp.296-301
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• 2020

Failure analysis on the welded type 304 pipe used for cooling water piping in the district heating primary side was conducted. Inorganic elements and bacteria in the cooling water and in corrosion products were analyzed, and the weldment was inspected by microscopy and a sensitization test. Corrosion damages were observed in the heat-affected zone, on weld defects such as incomplete fusion or excessive penetration caused by improper welding, or/and at the 6 o'clock position along the pipe axial direction. However, the level of concentration of chloride in the cooling water as low as 80 ppm has been reported to be not enough for even a sensitized type 304 steel, meaning that the additional corrosive factor was required for these corrosion damages. The factor leading to these corrosion damages was drawn to be the metabolisms of the types of bacteria, which is proved by the detection of proton, sulfur containing species, biofilms, and both bacteria and corrosion product analyses.

• Journal of Animal Science and Technology
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• v.64 no.5
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• pp.885-896
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• 2022

This experiment was conducted to investigate the effects of three different copper (Cu) sources (one inorganic and two organics) and levels (0, 50, and 100 mg/kg) on the growth performance, Cu digestibility, fecal mineral excretion, serum mineral concentration, jejunal morphology, and serum biochemical profile of growing pigs. A total of 42 male, growing pigs (31.08 ± 1.82 kg) were randomly assigned to seven treatments consisting of one negative control (0 mg/kg of added Cu level) and treatments with copper sulfate (CuSO4), Cu-amino acid complex (CuAA), and Cu-hydroxy-4-methylthio butanoate chelate complex (CuHMB) at 50 and 100 mg/kg each for 28 d. Pigs fed 50 or 100 mg/kg of Cu showed improved (p < 0.05) average daily gain and feed intake. Although Cu excretion decreased (p < 0.01) in pigs fed 100 mg/kg of organic Cu sources compared to those fed CuSO4, there was no difference between the Cu sources in pigs fed 50 mg/kg. However, the apparent total tract digestibility of Cu increased (p < 0.01) in pigs fed organic Cu sources compared with that in pigs fed CuSO4. The addition of CuHMB increased (p < 0.01) serum phosphorus and sulfur concentrations; however, there were no effects of source and level on jejunal morphology and serum biochemical profile. These results suggest that the inclusion (50 mg/kg) of organic Cu sources (CuAA and CuHMB) in the growing pig diet could be beneficial for growth performance and Cu availability and may reduce environmental pollution.

• Economic and Environmental Geology
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• v.44 no.1
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• pp.21-35
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• 2011

Inorganic and organic geochemical characteristics of Devonian bitumen carbonates in Alberta were studied using two drilling cores, Saleski 03-34-88-20w4 and Saleski 08-01-88-20w4, taken from the Core Research Center of Canada. The results of elements analyses showed high Total Inorganic Carbon, low Total Nitrogen and Total Sulfur, and Rock-Eval pyrolysis showed double $CO_2$ peaks in the oxidation part. These mean that the Devonian bitumen carbonates are mainly composed of dolomite formed by diagenesis, and its crystal texture is dominantly subhedral to anhedral but often euhedral. Bitumen contents were 3.6~19.0% in Saleski 3-34-88-20w4 and 5.0~16.4% in Saleski 08-01-88-20w4, respectively. As samples color become dark, bitumen and Total Organic Carbon contents are generally increasing in two cores. The results of biomarker analyses showed that the contents of resins and asphaltenes were 5~28% higher than those of saturated hydrocarbon, interring that the bitumen has been heavily biodegradated. According to the results of carbon isotope analyses in each component of bitumen, asphaltenes had highest values and the others had constant values. However, their values were varied in the range of normal crude oil (-18~-30‰).

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.1 s.28
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• pp.93-102
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• 2007

Particle materials sink in bottom and dissolved inorganic substances release from sediment and many kinds of materials continuously exchange in sediment and water column as well as transfer and transformation in sediment. The study of sediment quality means the state of sediment pollution relation of the water quality, sediment biota, materials fluxes between sediment and water column, transformation of materials in sediment is being important in recent. The state of sediment quality imply that the history of water pollution for long time, because the sediment quality does not change temporally. The sediment quality of bottom water can be used as a good indicator of pollution at present and in future. The major index of sediment qualities are the content of nutrients and hazard materials such as metals, Ignition Loss (IL), Total Sulfur (TS), Oxidation Reduction Potential (ORP), sediment COD, color, odor and the release of nutrients from sediment. However, there are some arguments between researchers about compare to estimation of sediment quality and sampling and analysis of sediment. In this study, I will introduce the method of sediment sampling, analyzing and estimating of the sediment pollution.

• Clean Technology
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• v.24 no.1
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• pp.70-76
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• 2018

Pyrolysis of Saccharina japonica in an Auger reactor was conducted by varying the temperature and the auger speed and then physicochemical properties of the S. japonica-derived pyrolysis oil were analyzed. The maximum yield of S. japonica-derived pyrolysis oil (32 wt%) was obtained at a pyrolysis temperature of $412^{\circ}C$ and an auger speed of 20 rpm. Due to low carbon content and high oxygen content in the pyrolysis oil, the higher heating value of S. japonica-derived pyrolysis oil was $23.6MJ\;kg^{-1}$, which was about 60% that of conventional hydrocarbon fuels. By GC/MS analysis, 1,4-Anhydro-d-galactitol, dianhydromannitol, 1-hydroxy 2-propanone and isosorbide were identified as the main chemical compounds of S. japonica-derived pyrolysis oil. The bio-char has low higher heating value ($13.0MJ\;kg^{-1}$) due to low carbon content and high oxygen content and contains a large amount of inorganic components and sulfur.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.12
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• pp.1126-1133
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• 2010

A two-stage biofilter was constructed and utilized to determine the removal efficiency when treating dynamic loading of a mixture of odorous compounds including benzene, toluene, p-xylene, ammonia and hydrogen sulfide. A yeast strain, Candida tropicalis, and a sulfur oxidizing bacterial (SOB) strain, Acidithiobacillus caldus sp., were immobilized in polyurethane media and packed in the two-stage biofilter. The experiment of dynamic loading variation was composed of (1) stepwise loading variation of all the odorous compounds (total EC test), (2) stepwise loading variation of each odorous compound, and (3) intermittent loading variation with 2-day-off and 3-day-on. The total EC test showed that the maximum elimination capacity was $61\;g/m^3/hr$ for total VOCs, and 5.2 and $9.1\;g/m^3/hr$ for ammonia and hydrogen, respectively. In addition, the inhibition between VOCs was observed when the loading of each individual VOC was varied. Especially the stepwise increase in toluene loading resulted in decreases of benzene and p-xylene removal efficiencies about 30% and 25%, respectively. However, the inhibition between organic and inorganic compounds was not observed. The intermittent loading variation with 2-day-off and 3-day-on showed that greater than 95% of the overall removal efficiency was restored in two days after the loading resumed. Consequently, the two-stage biofilter packed with immobilized microorganisms showed advantages over conventional biofilters for the simultaneous treatment of the mixture of organic and inorganic odorous compounds.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.9
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• pp.1035-1043
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• 2007

A leachate containing an elevated concentration of organic and inorganic compounds has the potential to contaminate adjacent soils and groundwater as well as downgradient areas of the watershed. Moreover high-strength ammonium concentrations in leachate can be toxic to aquatic ecological systems as well as consuming dissolved oxygen, due to ammonium oxidation, and thereby causing eutrophication of the watershed. In response to these concerns landfill stabilization and leachate treatment are required to reduce contaminant loading sand minimize effects on the environment. Compared with other treatment technologies, leachate recirculation technology is most effective for the pre-treatment of leachate and the acceleration of waste stabilization processes in a landfill. However, leachate recirculation that accelerates the decomposition of readily degradable organic matter might also be generating high-strength ammonium in the leachate. Since most landfill leachate having high concentrations of nitrogen also contain insufficient quantities of the organic carbon required for complete denitrification, we combined a shortcut biological nitrogen removal (SBNR) technology in order to solve the problem associated with the inability to denitrify the oxidized ammonium due to the lack of carbon sources. The accumulation of nitrite was successfully achieved at a 0.8 ratio of $NO_2^{-}-N/NO_x-N$ in an on-site reactor of the sequencing batch reactor (SBR) type that had operated for six hours in an aeration phase. The $NO_x$-N ratio in leachate produced following SBR treatment was reduced in the landfill and the denitrification mechanism is implied sulfur-based autotrophic denitrification and/or heterotrophic denitrification. The combined leachate recirculation with SBNR proved an effective technology for landfill stabilization and nitrogen removal in leachate.