Holcim Philippines, Inc; Davao City (Philippines)
Published in: World Cement 2/07
Holcim Philippines partners with Siemens in rehabilitating its mothballed line to meet market requirement in Southern Mindanao
Holcim is one of the world's leading suppliers of cement and aggregates. The Group has majority and minority interests in more than 70 countries on all continents and employs some 90,000 people. Holcim Philippines, Inc. is the leading cement manufacturer in the Philippines and operates in 4 major plants - one in La Union, another in Bulacan, a third in Davao City and the Lugait Plant in Misamis Oriental.
The Holcim Philippines-Davao Plant services most of the markets in the Southern and Central Mindanao, ARMM and exports markets. Strategically located about 960 km south of Manila, Holcim Phils.-Davao Plant has 3 lines with a combined clinker potential of 5,760 TPD.
In order to meet the market requirement in Southern Mindanao, rehabilitation of Line Number 2, which has been mothballed since 2000 was a vital decision made by Holcim Philippines. A careful study and evaluation of the conditions of the mothballed line went underway with great emphasis on safety and time.
Holcim Philippines was faced with a challenge of putting back Line 2 in operation at the least cost and at the shortest time possible.The Solution
The better option that came next to the original plan of connecting the MCC and the field instrumentation using the existing technology via the PLC junction boxes was the use of fieldbus communication.
Holcim Philippines, Inc. with the much needed savings on time and costs of cabling, testing and loop-checking took the better option: for the MCC, using the SIMOCODE DP where the normal 2 to 3 days completion of 1 MCC design was reduced to 2 MCC designs per day; and for the field instrumentation, using the Profibus PA that was more cost effective over the traditional 4-20 mA wiring and that can provide large number of diagnostics features of field instruments.The PCS7 Process Control System
Looking for a new control system and the possibilities that are offered by Fieldbus communication, Holcim Philippines awarded Siemens the contract to change the existing control system of Line Number 2 to the CEMAT process control system based on Simatic PCS7.
CEMAT is a process control system specifically designed for cement plants and has been well proven in this harsh environment over many years. The Davao cement plant has CEMAT version 3 in operation since 1996. The latest version of CEMAT V6.1 is now based on the mainstream process control system of Siemens, Simatic PCS 7, and offers unique, open architecture for modern, future-proof and economic solution for the cement industry. The easy and fast engineering with predefined CEMAT modules reduces the time for engineering, installation and commissioning drastically.
Trial starts can be avoided and this saves energy and improves capacity utilization with the sophisticated fault diagnostic and annunciation of CEMAT. Operator personnel can rely on information which shows all faults without exception and ensuring system acceptance. Fast troubleshooting can be assured because of detailed fault indication with high-performance plausibility logic. The reduced downtime of the plant leads to high availability and therefore higher output of the plant.
Because the life cycle of a cement plant is much longer than the service life of a single control system version, it is essential that the strategy behind the development of a control system stays innovative. CEMAT for the cement industry is designed with the future in mind, to guarantee compatibility with ongoing innovation. Even older versions of CEMAT - from V1.8 to V5 - can either be connected to the latest version or upgraded to this and later versions without difficulty. This saves money when investing in new plant equipment or during system upgrades.Intelligent Motor Control Center (MCC)
The decision to replace the conventional MCC with the SIMOCODE DP was a major turn-over in the installation. It simplified the motor control, thus saving time while completely achieving the uncompromising motor protection features that it promised. A total 156 Simocode DP was installed, replacing the conventional MCC.
Simocode meets all requirements for future proof energy management and offers advantages in all areas: in process management, operation management or in switchboards. Simocode provides an open communication via Profibus DB which makes it very easy to integrate it into the process control system. With innovative software, which is part of the Simatic PCS 7, a user-friendly parameterization, diagnostic, operator control and visualization is possible. With the predefined CEMAT function blocks for the Simocode it is very easy and comfortable to integrate motors into the process control strategy of the cement plant.Process Instrumentation
Field instrumentation Profibus PA provides a lot of advantages in the field instrumentation such as easier and faster cabling among the list. This type of communication, in addition to the cost effectiveness it offers due to its physical measurement, has large number of diagnostic features that allows the unit to provide very detailed information about the conditions of the instruments. For example, the Siemens pressure transmitter Sitrans P DS III has a number of integral diagnostics and simulation functions which permit users to specifically assess the status of a device during commissioning, servicing and maintenance.
Preventive maintenance is supported by functions such as:
- Operating hours counters for measuring capsule and electronics module
- Event counters for limit violations
- Minimum/Maximum pointers for pressure, sensor temperature and electronics temperature to record process extremes
- Two freely-configurable timers which can generate a warning or an alarm when a set value has been reached.
The device diagnostics effectively support troubleshooting in the context of corrective maintenance. The following are monitored cyclically:
- Memory integrity of RAM, ROM and EEPROM using the checksum method
- Program execution by means of monitoring certain checkpoints (watchdog)
- Sensor break and linearization calculation function.
Simulation functions are additionally available for checking the configuration of the transmitter and the controller input for intended functionality. These also contribute toward fast and specific troubleshooting and thus toward an increase in the efficiency of maintenance.
Measures can be derived from combination of the abovementioned functions which make a contribution towards predictive maintenance and thus increase the plant availability and help increase productivity.
The advantage of providing this information in addition to physical measurement is that you can plan the maintenance well ahead and only when it is necessary. The instrument will warn you in advance when it needs maintenance according the condition of the instrument.
Another big advantage is that in case of breakdown of the instrument, it will tell you not only that the instrument has failed but it will tell you which part of the instrument broke down. This reduces the trouble shooting time and allows the service engineer to take the correct actions. For example, if an instrument broke down because of too high temperature, the service engineer knows that replacing the instrument might result in the breakdown of the replacement and that he has to correct the temperature problem.
Because of the importance of preventive and predictive maintenance, Siemens is now offering the diagnostic features in a large range of Process Instrumentation. Not only the Pressure transmitters, but also other instruments like valve positioners, gas analyzers, level switches and the "cement radar" Sitrans LR400 have these features included. (Include picture of LR400)
Cemat is optimized for integration of distributed field devices into the process control system. The Process Device Manager (PDM) software - integrated part of Simatic PCS 7 - allows easy parameterization and optimizes the handling of the field devices. With Simatic PDM, you can use one software program to configure a number of field devices by different manufacturers using a single user interface. Process device data can be easily set, changed, checked for plausibility, managed and simulated.
With Holcim Philippines and Siemens working together for the success of the undertaking, the objective to finish the project within the specified time frame was made possible by choosing the Profibus approach. In less than the target number of days, Line Number 2 was brought back to life and started to produce clinker by the end of April 2006 from a long mothballed period of time.
"It was a breakthrough in the process of installation and maintenance. I was involved in the Simatic S5 installation in 1996 for Line Number 3 and I realized that the time to install and commission
PCS7 is considerably shorter than the old control system. It is important to invest in innovation. Developing new things out of it means helping the company achieve its thrust on cost efficiency," says Alden V. Malilong, Automation and Instrumentation Superintendent of Holcim Philippines, Inc. Davao Plant.
The application of bus communication in process control was the key tool in beating the deadline set by management. Though the technology of this type of data acquisition was long available, it was in this undertaking that we realized how fast and easy the installation and commissioning of each motor control was. I remember when I was directly involved during one of the upgrades of controls in the plant from relay to Simatic S5, cabling works accounted much of the work including the loop-checking of the cables to ensure that cables were correctly terminated. Disadvantages of this type of system are already identified (CPU error, static voltages and electromagnetic interferences.. etc), these has already been addressed by proper installation and cabling." added by Joel D. Nefulda, Maintenance Planner - Automation and Instrumentation of Holcim Phillippines, Inc. Davao Plant.
Profibus has allowed Holcim to cut the installation costs drastically and following this simple graph says it all.
In the meantime, while this line is up and running, Holcim is planning for the automation of the new Line Number 3. Needless to say, Profibus will be mostly preferred for the new control system. Holcim and Siemens are already in close coordination to ensure that this new line will be put back into operation as soon as possible. And when this line is finished, it will be the most advanced cement production line in the country.