CSR Charter Ⅰ Creating Value for Customers
Safety and Security 2: Processing Stage
Principle and Outline
Gas processing is a core and vital part of the Daigas Group's business operations. Its Senboku LNG Terminal and Himeji LNG Terminal process LNG into city gas and supply it to customers in a stable manner and to respond appropriately to their city gas demand. We are renovating and repairing our aging gas-processing facilities to secure facility safety and stable gas supply over the coming 10 years. We are also striving to devise more advanced safety and anti-disaster measures.
Flow of city gas manufacturing
LNG, used as a raw material of city gas, is transported by tankers and stockpiled in tanks set up at processing terminals. The LNG brought in is vaporized using heat from seawater. Its calorific value is adjusted and gas odor elements are added before it is delivered to customers as city gas.
Safety Measures at LNG Terminals
Our system docks LNG tankers safely
At the Osaka Gas LNG terminals at Senboku and Himeji, we strive for complete safety on site and in the surrounding areas. This safety begins as soon as the tankers carrying LNG dock at dedicated piers at the LNG terminals.
The tankers bringing LNG from around the world are docked with the utmost concern for safety. Osaka Gas developed its own system specifically for safely docking tankers through a series of processes. This system uses a GPS to monitor in real time the position of the tankers to an accuracy of 10 cm as they enter and leave the port, and dock and undock.
LNG tank safety measures
The LNG transported by tanker is fed into LNG tanks from the dock. To ensure a stable supply of natural gas, our two LNG terminals have a total of 29 LNG tanks, including one of the world's largest land-based tanks.
Tanks are equipped with advanced earthquake-proof technology. Should there be a gas leak, the tanks have dikes to stop the LNG from flowing to the outside. And there are high-expansion foam discharge systems and water curtain facilities to contain any spilt LNG.
Development and commercialization of a LNG tank using state-of-the-art technologies
Construction of the No. 5 LNG tank at the Senboku LNG Terminal, which began in 2012, was completed and its operation started in December 2105. The material of the interior wall of the tank is made from 7% nickel (Ni) steel, which contains 20% less of the rare metal nickel than conventional 9% Ni steel. This technology contributes to reducing procurement of material, the precious earth resource.
In addition, the Slipform engineering method* was employed in the construction of the concrete wall that constitutes the outer part of the tank. The use of this engineering method, the first for a domestic LNG tank, enabled significant shortening of construction duration. The completion of the No. 5 tank further ensured a stable city gas supply.
Odorization aids gas leak detection
At Osaka Gas's two LNG terminals, the LNG brought in by tankers at a temperature of -160℃ is vaporized using the heat of sea water, then the heating value of the gas is adjusted before it is delivered to customers.
Because natural gas is odorless, it is given a specific odor so that it can be detected in case of a gas leak.
Monitored 24 hours a day, 365 days a year
Central control rooms at LNG terminals carry out around-the-clock monitoring and operation of all processes from receipt of LNG, vaporizing of the gas, to delivery of the product.
These central control rooms also carry out monitoring and operation of all of the incident detectors and surveillance cameras so that problems are detected promptly and prevented from spreading.
If an incident detector picks up a problem, an alarm is sounded in the central control room and staff are on the scene immediately.
Disaster Prevention at LNG Terminals
Regular emergency drills
In addition to periodic operating drills using an operational control simulator, the LNG terminals hold drills to prepare for disasters and other emergency situations. We use these drills to continuously raise safety awareness among employees and improve their ability to safely manage our operations.
We hold a range of disaster drills as often as possible. These include fire drills using our on-site fire engines at each terminal, company-wide earthquake drills that are designed to deal with damage from an earthquake, spot drills with no prior notice given of the time or content of the drill, and joint drills with other companies operating in the neighborhood and local governments.
Conducting a Company-Wide Earthquake Drill along with a Business Continuity Plan (BCP) Training
In July 2013 the Daigas Group formulated the Business Continuity Plan (BCP) in the Event of Large-scale Disasters and Accidents and shared it across the Group to improve its ability to respond to accidents and disasters.
The BCP will in principle be reviewed once a year, in addition to earthquake drills education/ training via e-learning and other means to foster greater understanding among employees.
In the event of a large-scale earthquake, the Group must do all it can to ensure business continuity as well as to respond to the immediate needs associated with the disaster.
In fiscal 2017, by conducting BCP drills and earthquake drills together, the Group analyzed problems that surfaced through the drills and enhanced the comprehensive ability to respond to a large-scale disaster.