01.03.2019 Istanbul
LEAK CONTROL SYSTEMS BETWEEN WALLS IN DOUBLE WALL TANK AND PIPE APPLICATIONS
When we look at the last 50 years in the world, with the widespread use of fuel, there has been a significant increase in the number of locations where fuel is stored and shipped through pipes. Industrial facilities, residential heating use, fuel stations, etc. There are many points of storage and use. Of course, this increasing usage rate has brought with it different problems. The environmental pollution caused by the leakages in the installed systems and the increasing pollution rate in groundwater have revealed the need for the development of safer structures, and the use of double-walled storage tanks and pipes developed after this need has been started. Double-walled applications enable the establishment of more durable and safe structures compared to single-walled systems, and the creation of uninterrupted testing and traceable structures has been ensured with the developed leak control systems.
In our country, the use of double-walled tanks, whose application area expanded in the early 2000s, has become mandatory since 2012. However, many fuel distribution companies only include double-walled pipe applications in their specifications.
Since the use of double-walled tanks is mandatory, the presence of a wall control system in tanks is mandatory in TS 12820 4.2.1.1, and the draft work of the new TS 12820 is shown as one of the mandatory methods to be applied in article 4.2.2.1.
As Tora Petroleum, we offer solutions for leakage control of double-walled systems with the Thomas Brand, which is produced by Gardner Denver, one of the world’s leading manufacturers.
Thomas is one of the world’s largest companies producing different types of pumps and has 5o years of experience in leak detection systems in double-wall applications, during which time it has implemented approximately 1 million leak control systems. It has been applied in many different areas from central heating system tanks in houses to fuel stations, from industrial facilities to terminals. All systems are designed according to the principle of pressure or vacuum operation EN13160 accordance with Class 1 standard.
Double-walled tanks produced in our country are largely of the type expressed as Class 1 and can be tested on the condition that pressure or vacuum is applied between the wall. It is possible to control leaks in these tanks with Thomas brand Wall Control systems produced in accordance with En13160-2 standard.
If it is necessary to briefly mention the application and working principles;
In the figure on the right, pressurized type (Thomas D9) Leakage control system application is seen. As can be seen from the figure, Sistem Elektronik performs leakage control through a panel. The control panel presses the tank wall cavity (pressure line) with the appropriate pressure hoses installed by passing the suction air through a drying filter, and in the same way, the pressure between the appropriate pressure hose and the wall is connected to the panel again (measurement line) to create a continuous measurable structure. The operational value of the pressure applied between the wall is 450 mB, and if this continuously measured pressure value falls below 375 mB, the control panel will generate an audible and visual alarm and warn the users.
One of the biggest advantages of Pressure Type systems is a very economical solution. It is possible to provide leakage control through a single control panel up to 6 tanks proportional to the tank capacity. This is an advantage that significantly reduces the unit cost per tank. However, other advantages are;
• Overpressure protection system
• Audible and Visual Alarm
• 1 x External relay output
• In case of leakage, the wall remains dry
• Air Dryer prevents dampening between the filter and the wall
If it is necessary to explain the working principle a little more, the amount of pressure applied between the wall is higher than the maximum hydrostatic pressure that may occur in the tank. In the event of a leak in the tank wall, regardless of the lower or upper point of the liquid, the pressure between the wall will decrease and the system will create an alarm as a result. In addition, since the pressure between the wall is higher than the hydrostatic pressure in the tank, the stored liquid is prevented from coming out or filling between the wall in case of leakage. Very small leaks between the wall or pressure changes due to temperature are compensated by the internal pump on the control panel, and in case of large leaks, the alarm will be activated on the panel as the pressure between the wall will decrease slowly. As can be seen in the figure, it is possible to connect a single panel to up to six tanks with the connection manifolds used. In order to understand which tank has a problem after the pressure loss and the alarm, the tanks will be checked one by one with the help of the valves on the connection manifold and the problematic tank will be detected in a short time. Thanks to this system, which is extremely easy to install and commission, it is possible to easily prevent many safety, environmental and financial losses and problems that may be serious, and it is enough to allocate a very small budget for this.