• Tunnel and Underground Space
• /
• v.16 no.5 s.64
• /
• pp.387-393
• /
• 2006

This paper introduces the combination of two blasting methods applied to reduce blast-vibration and increase blast efficiency. NDC (New Deck Charge) blasting method using air deck effect with separation tube made of paper was effective to reduce blast-vibration, while blast efficiency was decreased a little in the bottom of a blasthole. Wide Space blasting method has an advantage to control the fragmentation and to increase blast efficiency over conventional blasting methods. In this study new blasting method combining NDC blasting method and Wide Space blasting method was applied to the field, it was confirmed to reduce blast-vibration and increase blast efficiency. It is expected to make useful blasting method to cover the public complaints and to shorten construction time by accumulating blasting data using new method with various conditions.

• Proceedings of the Korean Society for Rock Mechanics Conference
• /
• 2005.10a
• /
• pp.293-301
• /
• 2005

• Journal of the Korea Organic Resources Recycling Association
• /
• v.32 no.2
• /
• pp.37-48
• /
• 2024

Wastewater treatment plants (WWTPs) are obligated to reduce carbon emissions as a part of public sector greenhouse gas (GHG) emission reduction targets. However, Sewage Statistics(2022) shows that CO₂ emissions per wastewater treatment volumes have decreased by only 3.03 % compared to 2020, which is far from enough to meet the Nationally Determined Contribution (NDC) targets. This study aimed to find operational conditions of biological reactors that minimize total carbon footprint (CFP). Total CFP considers both direct emissions from biological processes and indirect emissions from energy consumption. A study was conducted using a computer simulation program which is called as EQPS for a 4-stage BNR WWTP. The results showed that total CFP was reduced by 10.97% compared to the design condition when the mixed liquor recirculation (MLR) was set to 100 % of the influent flow. The N₂O emission factor (EF) of the target WWTP was calculated to be 0.138-0.199 %, which is significantly lower than the IPCC default value of 1.6 %. This study proposes a method to minimize total CFP in WWTPs by optimizing biological reactor operation and emphasizes the need for further research on N₂O emission reduction.