Industries & Applications - Power Energy

Title: Demineralized (DM) Water Plant

Industry: Power,Cement,Steel or any industry, which needs (DM) water

Business Challenge:
Demineralization is the process of removing mineral salts from water by using the ion exchange process. Dematerialized water also known as Deionizer water, water that has had its mineral ions removed. Mineral ions such as cations of sodium, calcium, iron, copper, etc. and anions such as chloride, sulphate, nitrate, etc. are common ions present in water. Deionization is a physical process, which uses specially manufactured ion exchange resins, which provides ion exchange site for the replacement of the mineral salts in water with water forming H+ and OH- ions. Process automation can make a major contribution to improving plant efficiency. To increasing availability, increasing efficiency, and controlling emissions is a major requirement of the power industry today, and its importance will grow in the future. This causes industrial organizations to purchase control and instrumentation systems first on price, so that organization is able to control, monitor the complete plant remotely with ease access.

We are committed to provide solutions to its customers as “start with, live with, and grow with”. In order to help operations in industry and realize a greater value, lower cost-of-ownership from their automation technology investments. This approach is applicable to end users in particular & developing regions, which are increasingly concerned about the long-term costs of maintaining their control systems assets. Compact Programmable Logic Controllers (PLCs) to meet the needs of customers with a wide range of industrial infrastructure projects.

The Master Logic solution provides the versatility and low cost commonly associated with PLCs and augments it with a global support network and the ability to integrate with the industry’s newest control systems-Experion-HS. A versatile line-up of I/O modules and networking options enables flexibility in how the controller fits into an entire automation scheme. The Master Logic (ML PLC) & EPKS Control system integration enables to read/write PLC data and monitor PLC alarms and events from Experion Station. Master Logic is designed to bring power and robustness to very high-speed logic, interlock and sequencing applications. Using the Experion-HS SCADA system we can generate the graphical (Standard/Customized) representation as per the application requirement.

Activities comes under the Engineering solution of each control system –

  • Engineering Documentation (HDM,I/O Assignment, System Architecture)
  • Software development (Control logic, Graphics, Database, Alarm management)
  • FAT (Factory Acceptance Test)-Visual inspection & testing of hardware
  • Site Commissioning
  • SAT (Site Acceptance Test)-operation & maintenance Training, Handover etc.

Here is the detail of all above-mentioned packages that are controlled & operated from ML PLC & Experion-HS SCADA

Application: DM Water Plant
De-mineralization technology is the proven process for treatment of water. A DM Water System produces mineral free water by operating on the principles of ion exchange, Degasification, and polishing. Dematerialized Water System finds wide application in the field of steam, power, process, and cooling. Clarified water shall be available at battery limit, which shall be initially passed through PSF for the purpose of filtration. Outlet of PSF shall be stored in Filter Water storage tank. Filtered water from this tank is utilized for different plant services. ACF is provided for the removal of organic matter and residual chlorine, if any in water, which will be potable water. Outlet from PSF enters into the Softener units and the Demineralization (DM) units of Strong Acid Cation Exchanger, Degasser Towers with storage tanks and Degassed Water Transfer Pumps, Strong Base Anion Exchanger, and Mixed Bed Exchanger. The DM water from MB shall be sent to the DM water storage tank. DM water from this tank is pumped for regeneration through 2 Nos. of DM regeneration pumps. Drain from various vessels and regeneration waste from various units like SF, SAC, SBA and MB are collected through the drain channel and taken to Neutralization Pit for pH conditioning and then for disposal. The neutralized effluent from N-pit is transferred to Effluent treatment plant through Effluent Transfer pumps. The back wash waste of PSF, ACF & final rinsing waste from the various units like SF, SAC, SBA and MB is collected through the drain channel and taken to Filter Backwash Pit.

Benefits of Automation /Control system for various applications -

  • Monitor & Control the entire system from control room.
  • Live status from the field.
  • Interface option to communicate with third-party devices using user-defined protocol.
  • Enhanced redundancy features including fast switchover time, high-speed synchronization and dual ring topology option.
  • Flexibility of network options (Fast Ethernet, Modbus ASCII/RTU/TCP)
  • Variety of I/O modules including channel-to-channel isolation
  • Robust diagnostics (system/error logs, system monitoring, network monitoring, ping test, frame monitor)
  • Tight integration with Experian HS via dedicated protocol
  • Integrated programming and engineering environment with Soft Master.

The control operation performed in three different ways i.e. Auto, semi auto & manual mode.

  1. In semi-auto mode, the starting of a service/backwash/regeneration will be through keyboard operation to be initiated by operator. Once operator initiates the operation of regeneration/backwash, the sequence of regeneration/backwash shall be automatic. Upon completion of complete regeneration/backwash, the service cycle will proceed after initiation of the same by the operator. Operator in coordination will complete sequence of Pressure Sand Filter and Activated Carbon Filter backwashing with the Ion-exchange units of respective streams.

  2. Under remote-manual mode, each step / sequence of regeneration / backwash will be initiated by the operator from keyboard. In local-manual mode, the individual valves/pumps etc. can be operated locally and the operator can also decide duration of each step.

  3. Each solenoid-operated valve will be provided on the HMI. Green indicates that the valve is open and Red indicates that the valve is closed.

The operation of softener Unit /Demoralized (SAC/SBA/MB) plant performed with the following details

  1. The following PBs shall be configured on the HMI to perform operation in Auto/Semi auto:

    1. START– To start the REGENERATION operation.
    2. STOP – To stop the REGENERATION operation.
    3. HOLD / RELEASE – Press to HOLD the step and RELEASE to proceed to next step.
    4. SKIP – To skip the existing step.

  2. Different Valves/Drives open/close or start/stop based on the below sequence operation logic:

    Service Mode: Rinse/Refill/service/Off
    Backwash Mode: Backwash/Air Release/Rinse
    Mixed Bed Exchanger & its valve sequence:

  • Typical Standard Graphics
  • Typical System Architecture
  • Project Detail
Capacity Analog Input Analog Output Digital Input Digital Output Total I/O Customer Name
2 X 660MW Thermal Power Plant 59 17 874 350 1300 Rajasthan RajyaVidyutUtpadan Nigam Ltd