Background
The goal to which the experts of Dunea are committed to every day is the production of high quality and reliable drinking water in harmony with nature. Over 1.2 million people living in the western part of South Holland rely on Dunea to supply drinking water 24 hours a day. Water is abstracted in the dunes between the cities Monster and Katwijk located along the North Sea coast. The method for preparing drinking water is unique and not used anywhere else in the world. Dune passage is a natural treatment method whereby human errors are practically ruled out and forms an environmentally friendly alternative to the purification of water with chemicals. The water resources in the dunes are sufficient for months of supply. Besides the purification of drinking water, Dunea manages the stunning nature of the dunes and protects the abstraction of drinking water.
• Sensor with special coating and IP 68 allows for buried installation
• Fully welded maintenance free construction with no moving parts
• Accurate and reliable measurements
Measurement requirements
Dunea required electromagnetic flowmeters for the accurate measurement of the volume of water that is transported from its water resources in the dunes to its purification plant. The pipe has a diameter of DN 900. The main requirement of Dunea for the flowmeter has been that it is installed underground and that it is protected against temporary submersion. Also the accuracy and reliability of the measurement have been taken into consideration while selecting a flowmeter. In order to maintain the water balance, Dunea gets permission for abstracting water from its resources and therefore the volumes of water needs to be monitored accurately. See the location of the flowmeter, any repair or maintenance activities that need to be done are very costly..
Solution
For applications where the flowmeter is subject to temporary or permanent submersion under water, such as in basements, pits or locations where the meter is buried underground, KROHNE has an excellent solution: the OPTIFLUX 2000.
• The measuring tube consists of a fully welded stainless steel construction. As a result the construction is 100% water tight and leak free. It is not necessary to use burial (‘bitu’) tape as is often the case with threaded constructions.
• The flow meter can be constructed entirely of stainless steel and has no plastic parts. Also the connection box on the flow sensor, for housing the power cables between the flow sensor and the converter, can be supplied in stainless steel. Competitive products often use plastic materials, whose quality deteriorate over time and may cause leaks.
• The cables can be poured off already during manufacturing in the factory in lengths specified by the customer. During installation no additional actions are needed.
• The flow sensor can be provided with a ground coating especially developed for the buried installations.
Customer benefits
The excavation of a meter, for example for maintenance purpose, comes with high costs which the customer wants to avoid as much as possible. The maintenancefree construction of OPTIFLUX 2000, as described above, gave Dunea the confidence to choose for the KROHNE solution. Moreover, the PTIFLUX 2000 is very easy to install. Integrated diagnostic functions offer the customer the assurance that should problem arise either in the process or with the flow meter, the customer receives a warning. This construction is used by Dunea and many other clients already for years to their complete satisfaction in underground installations.
Products Used
OPTIFLUX 2000 electromagnetic flowmeter
• Diameter range up to DN3000
• IP 68 protection class
• Polypropylene or hard rubber liner
