This study assesses greenhouse gas evolution from construction-material manufacturing facilities and estimates the potential reduction of these gases via the future massive sequestration of carbon dioxide. The scope of the evaluation specifically targets the global-warming potential in terms of kg-CO2 equivalent/tonnage industrial waste. Life cycle assessment (LCA) is a method to quantitatively analyze the input and output of a specific material resource during its life cycle from raw-material acquisition to final disposal as well as its environmental effect(s). LCA comprises four steps: its objective and definition of the scope, the entire life-cycle analysis list, an evaluation of its effects, and life-cycle analysis. The annual inflow of petro-ash reaches 300,000 tons, and this material is transported via screw-driving systems. The composition of the petro-ash is 1.2% volatile compounds, 6.8% fixed carbon and 92% ash contents. A total of 38,181,891 Nm3/yr of carbon dioxide is sequestrated, which is equivalent to 75,000 tons per annum and 304.5 kg/ton of petro-ash waste, with 250 kg/ton of the latter sequestrated as calcium carbonate. The final analysis on the effect of one ton of petro ash in construction materials showed 27.6 kg-CO2 eq emission. According to the final LCA analysis, only 27.6 kg-CO2 eq/ton was emitted by the petro-ash that was used in construction materials if CO2 fixation during carbonate mineralization was considered, where -250 kg-CO2 eq/ton positively contributed to the LCA. In the future, commercial-scale process modification via the realization of continuous processes and the more efficient reduction of carbon dioxide is anticipated.

The purpose of this study was to investigate and analyze continuous operation of food waste resources at Dongdaemun Environmental Resources Center and to improve the overall operation of the dry anaerobic digester facility. Korean domestic food wastes consist of 18% total solid (TS) content but food waste is difficult to utilize for dry anaerobic digestion. Other operational trouble-shooting resulted from the inherent design, construction and operation of such a biomass generation facility based on 100% utilization of dewatered cake with 35% TS concentration as feedstock, causing the accumulation of unwanted solid residues. A materials flow analysis obtained from actual operation of the anaerobic digestion facility revealed that the organic material loading rate (OLR) and its residence time were 8.3 kg-VS/m3·day and 18.3 days, which adversely affected stable operation. The OLR was occasionally > 15,000 mg/L organic acid concentration and the facility shut down. Such anomalies drastically reduced biogas production and increased organic matter loading in the wastewater, which exceeded the legally allowed concentration limit. Operation of this facility has been normalized to the targeted facility capacity of 98 m3/day based on the results of this study.

Mineral carbonation, the return technology of Carbon dioxide into the Nature as a generating source, has been studied by advanced countries. Industrial by-products can be used as economical resource for mineral carbonation. This study is intended as an investigation of effluent recycling of liquid carbonation with carbon dioxide fixation using industrial by-products. The nitrogen and carbon dioxide was used by mixing the same as the exhaust gas concentration 15vol%. Carbon dioxide absorbent was used as Mono Ethanol Amine (MEA) concentration of 5~30wt% and then concentration of carbon dioxide absorption were analyzed. After carbonation reaction, Concentration of dissolved inorganic cations and conversion of carbonation were analyzed by ion chromatography, thermogravimetric, x-ray diffraction, scanning electron microscope(SEM). Effluent was recycled MEA and water using RO system. These results Confirmed potential of CO2 reduction and Utilization of carbonation using industrial by-products.

In this study, we examined the liquid carbonation reaction using recycled aggregates as an industrial by-products. This research deals with carbon fixation with a precipitation reaction utilizing 5 wt% and 30 wt% alkanolamine absorbents in an aqueous calcium oxide solution. Unlike carbon fixation operated at high temperature and pressure that consumes a lot of energy, we conducted experiments at moderate temperature (303.15 K) and pressure (1 atm). By adding calcium oxide solution into the carbon dioxide saturated solution, carbonated recycled aggregate was formed. To verify the physical properties of products, XRD analysis was performed and SEM images were obtained.

In this work, we constructed the sulfur polymer cement(SPC) concrete using coal bottom ash from 4 thermal power stations in korea and investigated their practical data for production of industrial construction compounds. To manufacture the SPC concrete, we used batch concrete mixer with the heating jacket using hot oil. Also, coal bottom ash was used as a fine aggregate below 2 mm. When the SPC concrete were produced with diverse sulfur concentration (15, 20, 25, 30 wt%), compressive strength properties were analyzed. We got the compressive strength of the maximum 60 MPa. These experimental results could be effectively applied to the recycling technology of coal bottom ash.

The salt water generated from the salting process of kimchi production is difficult to treat biologically due to very high content of salt. When salt water is treated and discharged, it cannot satisfy the criteria for effluent water quality in clean areas, while resources such as the salt to be recycled and the industrial water are wasted. Therefore, in order to recycle salt water and improve the economy of kimchi production process, a basic study was conducted on the treatment using electrochemical oxidation of organic acids and organic matters existing in large volumes of salt water. The electrochemical treatment of organic matters has advantages over conventional methods such as active carbon absorption process, chemical oxidation, and biological treatment because the response speed is faster and it does not require expensive, harmful oxidizing agents. In this study, the electrochemical oxidation characteristics according to current density and pH were evaluated with acetic, lactic, and formic acids existing in large volumes of salt water. Acetic acid was refractory to electrochemical oxidation regardless of current density, while lactic acid showed high removal efficiency even at low amount of current. Furthermore, formic acid showed the highest current efficiency for the first 20 minutes and its removal rate increased together with the amount of current. In the experiments with the initial pH set to 4, 7, and 10, the removal rate of organic acids tended to be higher at lower pH values. Because NaCl was used as the electrolyte, HOCl was produced at pH 4 and OCl− increased at pH7. The germicidal power of HOCl is about 40-80 times higher than that of OCl−. For this reason, the generation of HOCl with excellent oxidizing power increased at pH 4 and the highest removal rate was achieved. Furthermore, as salt water contains various organic matters, an experiment on organic acid compounds was conducted to see the effects they have on electrochemical oxidation. As a result, it was found that lactic acid and formic acid could be used for simultaneous treatment even when they coexisted, whereas acetic acid is refractory to electrochemical oxidation. Furthermore, lactic acid showed the highest electrochemical treatment efficiency, followed by formic acid, and acetic acid.