Written by Adva Harel, General Engineers

What do you do when you are thirsty? Naturally, you open the tab or use your home drinking device and simply pour water, and drink…

Did you ever stop to think how the water you drink is treated and delivered to us at the required quality level? Or what is the treatment process our water goes through – from its natural state, all the way through to deserve drinking?

Mekorot – Israel National Water Company – supplies most of the drinking water in Israel, and is in charge of the Filtration Plant where a GE Automation System is installed. The water treatment process is a technological advanced process based on a number of automation, and computerized monitoring systems. The clean water we drink goes through a long and complex journey which is controlled by GE Process Control system.

The vision

For Mekorot – delivering reliable water available 100% of the time and at the highest quality level is top priority. To achieve this, Mekorot established a Central Filtration Center at Eshkol Site, in northern Israel. This Filtration Center is one of its kind in Israel, and the 4^th largest worldwide.

The Filtration Center was already designed by Mekorot 20 years ago, after recognizing that the quality of water supplied from Lake Kinneret (Sea of Galilee) and other sources, must be improved. Therefore, a committee including representatives from the Israeli Government, recommended to Israel Water Authority to filter the water of the National Water Carrier, so that it continues to serve as the main source of drinking water in Israel. Following the acceptance of these recommendations, the Water Authority started evaluating the alternate options for handling the water filtration process, and the Central Filtration Center at Eshkol Site was established.

“We started building the plant back in September 2003 with the EL-PC Group, as a Turnkey Project” said Nuriel Meraro, Command & Control Engineering Manager of Mekorot’s Jordan Valley Division. “In parallel, Mekorot started preparing for the challenging task of operating and maintaining the plant.”  Nuriel adds that “the Central Filtration Plant is operated using two identical modules which work independently and have full back-up, to enable continuous and reliable operation. The process starts by pumping water from Lake Kinneret at the Sapir Site – as Lake Kinneret is 212 meters below sea level it has to be lifted to 152 meters above sea level. From Sapir Site, the pumped water flows through pipes and open canals to the Eshkol Site, where treatment and filtration processes are performed to bring them to the highest drinking quality levels.”  

Smart Control System and Energy Efficiency

“As the Engineering Manager responsible for Automation at Mekorot Jordan Valley Division, and along with our Process Engineering and Water Supply teams, we are in charge of writing the Functional Specifications of our systems and devices” notes Nuriel. “We aim to achieve high Energy Efficiency and Process Efficiency, so that we can facilitate cost reduction in the production of water. To achieve this we have to leverage operations support systems and programming tools, which enable real-time decision making”.

Nuriel supervises the implementation of infrastructure systems to best meet the requirements of the plant. “It is important for us to use state-of-the-art technology, understand the requirements of the system, and find the best solution for each element in the filtration process. We keep upgrading the system while in process. This proves to be a complex process as the plant operates 24×7 throughout the year – except once a year, when the flow of water in the National Carrier is stopped for maintenance and upgrades which cannot be performed while the water is flowing. Stopping the water flow in the National Carrier is a project for which we prepare half a year in advance!”

Overall Experience and Best Performance

We toured the Eshkol Site in northern Israel, and could not remain indifferent to the beautiful blue landscape of the plant. Our first stop was at the Settling Reservoir – the first step in the treatment of the water which flows from the National Carrier. At this point, Aluminum Sulfate is added to the water to generate the flocculation process – the formation of particles which float in the water into large and heavy crystals which sink to the bottom of the reservoir. The water then passes from the Settling Reservoir into two Thickeners which complete the process by hydraulic mixing at varying speeds. At the Eshkol site there is a chemical farm which stores 9 different types of chemicals to treat the water into high quality levels. At the other end of the reservoir, the water is gathered in another operational reservoir to regulate the flow of the water back into the National Carrier. After the flow of clean water is back in the National Carrier, it is transported south and into the national water supply system that runs throughout Israel. From there – water is transported to industrial, agricultural and urban customers.

“Another interesting project”, tells Nuriel “is the treatment system for the sludge of the filtration plant. Sludge settles in the Settling Reservoir from the process of filters cleaning. This sludge contains a lot of water we wish to return to the filtration process and turn into potable water. It is for this purpose that the need for a new Sludge Facility arose.  The sludge gets pumped from the Settling Reservoir and flows into Thickeners, then to Dryers and via a conveyance system into the Removal Containers. The returned water flows back into the Settling Reservoir – and this way precious water is saved!”

 Our next stop in our tour was the new and very impressive Control and Monitoring Center. Dozens of monitors reflect and track the automation system of the filtration plant, and in the near future – additional screens will be added to control and monitor the Sludge Treatment Process.

The Control and Automation Platform at the Filtration Plant is based on solutions from GE Intelligent Platforms, which are represented in Israel by General Engineers – GEIP Channel Partner for Automation and SW Solutions. According to Nuriel Meraro “the control system at the plant performs automatic monitoring and control of the devices from a single control center. This creates an environment in which minimal intervention by operational staff is required. General Engineers implemented a reliable and automated control system, working in Redundancy to provide the highest availability and enable full backup of the controller.”

The automation system is a mission critical system, since the filtration plant must operate at all times – otherwise water will not flow into the National Carrier. It is therefore crucial for the system to be available and provide a reliable and error-free response.

The Control System is based on PACSystem Rx3i PLCs by GE, in a redundant architecture, through all the control layers – from the I/O and end devices, to the controllers and the HMI system. The PLCs are wired with fiber optic cables to ensure fastest failover communication (communicates at the same scan time). The system includes 7 pairs of Rx3i PLCs, controlling 6000 I/O points in redundancy. According to Nuriel, the decision to select GE control system for the operation of the plant was based on a few criteria: Operation with fewer shifts and personnel, high availability of the system and high and proven reliability.

The control system is monitored with Proficy Cimplicity HMI/SCADA solution, by GE Intelligent Platforms. Customizing Proficy Cimplicity to the requirements of Mekorot enables optimal control of the Filtration processes.

Hertzel Perry, Technical Manager for Control and Communication Systems of General Engineers, suggests that “High availability and survivability of the industrial control systems (PLCs, HMI, and Data Collection) enable customers to dramatically reduce the downtime of the process during a breakdown or preventative maintenance, thus maximizing the efficiency and utilization of the system. PACSystem controllers along with Proficy Cimplicity HMI/SCADA system provide the highest flexibility in their implementation a well as cost reduction for the end customers. “

Zachi Stromza, Automation and SW Solution Division Manager of General Engineers, adds that “in the complex and diverse projects of our National Water Company – Mekorot, General Engineers introduced their various capabilities in the field of control and software, by implementing the solutions of General Electric. Mekorot faced challenging targets in the last seven decades of the Israeli Water market. We feel proud to be part of turning these challenges into reality with our advanced solutions and our engineering expertise. “