In this case study we will look at the optimisation of an RO installation at our customer Bruine de Bruin in Aalsmeer. The purpose of this RO installation is to obtain usable cooling water for the industry. Bruine de Bruin has been a manufacturer of various water treatment equipment since 1965 and, like JUMO, has a worldwide distribution network.
The membrane technology of reverse osmosis works by means of a pressure difference on two sides of a semi-permeable membrane. This membrane has the ability to separate the substances present in the water, such as salts, heavy metals, bacteria, viruses and moulds. Reverse osmosis is an environmentally friendly method. No chemicals are used.
An RO installation from Bruine de Bruin is fed with anaerobic spring water which is passed through the installation under the required pressure. So-called candle filters are used to keep external contamination out of the RO installation and prevent pipe failures. The water is forced through one or more elongated elements - also known as candles - in a pressure vessel. This is done from the outside in, leaving the particles to be caught on the outside. These filters are monitored by a differential pressure measurement. A centrifugal pump then brings the water to the desired working pressure so that the membranes can effectively separate the water and salts by means of reverse osmosis.
The delivery of every RO installation is preceded by the necessary research. First, the specific wishes of the customer are taken into account. Then, an analysis is made of the available water (feed water). There are many types of water; sea water, well water, tap water, waste water or surface water. Each type of water is different and makes specific demands on water treatment technology. Depending on the treatment, Bruine de Bruin applies various types of membranes, suitable, among other things, for tap water, brackish water, seawater or waste water.
In addition to the choice of membrane, water analysis is indispensable for any RO installation. The design of the required RO installation is determined by, among other things, the intended capacity and the quality of the water. To maintain the correct water quality in the RO installation, Bruine de Bruin used sensor technology from JUMO.
The water level in a clean water storage tank filled by the RO installation is continuously monitored using level sensors. During level monitoring, the measured pressure is transmitted to the measuring system of the level sensor as a standard signal. This signal is linearly proportional to the rising liquid column in the clean water storage. For this task, Bruine used level sensors from JUMO. The core of the JUMO MAERA level measurement probe is the piezoresistive measuring cell that stands out for its high load capacity and guarantees safe, reliable and temperature-resistant measurement. The integrated reverse polarity protection of the power supply protects the measuring instrument from damage and ensures maximum safety during start-up.
The candle filters installed on the RO installation are monitored by differential pressure measurement. For this purpose, de Bruin used the JUMO MIDAS pressure sensor. This pressure sensor offers long-term measurement stability of <0.2% and is easy to install, both mechanically and electrically. This pressure transmitter features a fully automatic measuring and calibration device and offers a diagnostic function on the switching circuit. With the Quickon clamping technology, the spring contacts ensure a reliable electrical connection, even in the event of large temperature fluctuations. This electrical connection significantly reduces installation time and associated costs.