Festo Valves > Festo DAPS actuators managing water on the South African Coast

A coastline in South Africa that has a water shortage is looking for a solution; the solution to this is simple improvements to their water treatment plant.

Here’s how droughts were avoided using Festo pneumatic products to improve their water supply issues. Using Festo DAP and DLP actuators linked to MLV valve terminals for pneumatic control.

On the South African coast you are not short of nutritional water. The South African water treatment plant receives their freshwater via groundwells in addition to the reservoir dam in the mountains, in recent years the water level has dropped considerably. The lower water level is caused by the growing requirement for H20 as a result of buildings being built quickly. This has led to the South African authorities taking action, which includes improvements to the old water treatment plant by adding additional automation to improve performance.

The South African authorities wanted to swap electric valves for closing and opening ball valves or butterfly valves with pneumatic actuators.

Festo convinced the South African authorities that using pneumatics would lower installation, initial capital costs and investment, compared with the electrical equivalents by as much as fifty percent.

During their lifetime pneumatic drives are maintenace free. Build ups may appear that result in considerably greater breakaway torques due to the fact that process valves are not regularly actuated. This particular overload protection of pneumatics is a vital function here. When the drive involves a period of standstill, the pressure can be simply improved in the pressure regulator to be able to apply more force therefore no need for expensive maintenance. A benefit is that compressed air is available even in the event of a power cut, due to an air reservoir for preparation and generation.

The South African authorities’ substituted butterfly valves found at filter basins for pneumatic positioners and actuators from Festo in addition to installing control loops that have both level and flow sensors. The slide valves and butterfly valves in the ultra filtration plants and sand bed filters in the water treatment plant are currently built with DAPS and DLP actuators.  DLP , is the perfect solution for safety, shut off and control slide valves. It works right on the slide gate therefore guaranteeing numerous positions that could be approached precisely. As it has a large corrosion resistance therefore it can be utilized with no difficulties outside and will not be impacted by the Coasts salty atmosphere. The Festo DAPS actuator can control both butterfly valves as well as ball valves with numerous media flows and an angle rotation that it limited to 90 degrees.

The rotation is created from the scotch yoke mechanism, therefore helping to address the valves high breakaway rotation. Festo decentralised MPL valve terminal is the main part of pneumatic systems used in water technology. They are perfect for the quick and easy automation solutions that feature maximum interaction of the pneumatic and electric parts as well as process valves. Festo valve terminals possess modular configuration relevant to the number of Festo process valves, whereas the fieldbus supplies  systems with a individual, well defined, standardised interface between your controller (PLC) as well as the valve terminal. The system concept benefits from the fact that additions or changes can easily be produced, while not needing to buy new equipment.

Festo butterfly valves are controlled by Festo MPA valve terminal. They in addition have the information of the filters present position by identifying its differential pressure, flow rate and fill level.  If a filter needed to be cleaned, the PLC that controls the valve terminal, and this inturn then the butterfly valves are actuated, in line with the cleaning programme. After the cleaning is complete, the normal function resumes. Festo valve terminals are set up according how many pneumatic drives it has, limit switches or measuring equipment.

The improved water plant now has a total capacity of twenty eight million litres of water that is drinkable every day. The groundwater that is pumped directly into the plant is then treated by a biological filter system.

For more information on the Festo DAPS Actuator or any Festo pneumatics products contact us at Electroquip today.