Consistent production output and consistent quality levels were just two of the benefits realized when this edible oil manufacturer turned to automation for its Philippines refinery.
By Bob Gill.

If you're a fast-food fan then you probably do not pay too much attention to what goes on behind those brightly lit counters in McDonalds, Burger King, Jollibee, etc, more concerned as you are with filling your famished stomach with those tasty fries, burgers and nuggets that your doctor is always telling you to go easy on. But look a little closer and you'll see those fries bubbling away and those juicy chicken breasts being brought to finger licking perfection back in the kitchen.

It's cooking oil, of course. And in the Philippines, in Quezon City, there is a company that goes by the name of Oleo-Fats that is the number one supplier of specialty fats and oils to the country's food industry. And apart from the fast food segment, of which it already has 90-percent market share, the company's oils find their way into an array of ready-made products such as ice cream, pastries, baby formula, and biscuits and chocolate. And while those delicious fries may not be exactly healthy, Oleo-Fats' business certainly is, with annual growth of around 10 percent per year.

In terms of manufacturing, what takes place at the Oleo-Fats site is essentially a (continuous) refining process on the vegetable oil feedstock, which comes in the form of "crude" coconut oil originating from fruit of Cocos nucifera, an oil crop that is widely grown in the Philippines, as well as other vegetable oils.

The processing steps to get to a refined oil include degumming, neutralization, bleaching, and deodorization. That "straight" oil can then be sold as a frying product, or undergo further processing such as blending or hydrogenating to realize a number of other products available from Oleo-Fats, such as for ice cream and soft candy applications, and hamburger buns and other baked products.



Seeking automation
"Ever since we started operations in 1987 it had always been a manual process," explains Oleo-Fats plant manager Gerry Guanlao. "But three years ago we seriously started to take a look at automation as a means of overcoming certain issues associated with having a manual process."

Some of these issues included: recording of critical parameters via pen-and-paper, which made data analysis arduous; slow reaction to process alarms and upsets such that extensive wastage could occur before rectification action; material balance (input versus output) not being available in real time; control valves not providing open/ close feedback status, making it difficult for operators to determine their status; and no possibility of connection to the company's information system.

"Going for automation was really all about giving us ease of operation," says Guanlao. "Instead of people going up and down the floors looking at gauges and opening valves, we wanted to have the ability to see the whole picture from one single location and remotely monitor and control from there."

The next step was to find an automation supplier that could deliver on Oleo-Fats' requirements. Three brandname, globally renowned companies were considered. So how to make a selection? "We looked at similar refining plants in Malaysia and found that the majority were using Siemens for the automation," he recalls. "We were also fortunate in being able to get the services of a consultant, formerly from Unilever and quite a renowned automation guru in the Philippines, and he was also more inclined towards Siemens.

The Oleo-Fats plant manager also felt that the staff from Siemens Philippines were better able to explain their offering as compared to the other two bidders. And a final clincher was after-sales service. "Those two companies were referring us to a third party for services, which we didn't like. We wanted to be able to go directly to the vendor in case of any problems. And Siemens gave us that assurance."

Picking Profibus
The first phase of the automation project saw two of the physical refining plants, PRP 3 and PRP 5, converted from their previous manual operation. In terms of control, the system supplied was essentially SCADA plus PLC, or in Siemens terms, WinCC plus S7-400 controllers. At the field level, the motors, valves and process instruments came from a variety of suppliers.

And for the field network, AS-i bus was chosen, on the recommendation of the aforementioned project consultant, who was familiar with the technology. An IE/AS-i link device is used to connect the field network to an industrial Ethernet network on which the PLCs and Operator Stations are connected.

However, when it came to the second phase, which involved refining plants PRP 1 and PRP 6, the automation sophistication took a step up with the decision to use fully digital Profibus PA devices for the process instruments, while keeping AS-i bus for the motors, on/off valves, and level switches. Here, a DP/PA coupler is used for interfacing the Profibus DP cable segment from the PLC to the Profibus PA network.



The extensive use of Profibus PA for the likes of mass flowmeters, radar level transmitters, pressure transmitters, and modulating valves makes the Oleo-Fats site one of the most significant Profibus implementations thus far in Southeast Asia. For while it is now common to see projects with Profibus DP segments connected out to remote I/O units such as the Siemens ET 200, it is still rare to see a wholly digital fieldbus connection right down to the process instrument. And while Profibus PA instruments are more expensive than conventional analog, Oleo-Fats believes that the lower installation costs and the longer-term asset management benefits mean that they are well worth the investment.



No turning back
"It was like going from driving a car with manual transmission and stick shift to an automatic one," says Gerry Guanlao, explaining the impact of the automation technology introduced to Oleo-Fats' production lines. "Some of the staff were initially hesitant, but after about a month of getting used to all the automated control and monitoring they really did not want to go back!"

As outlined by Rad Go, manager – service and support, Siemens Philippines, functions newly enabled by the Siemens system include: automatic ratio control for blending of activated carbon based on actual flow rate, to allow more consistent product quality and hence lower costs; actuation of alarms automatically initiating appropriate responses, such as switching off a tank to prevent tank overfill; and real-time monitoring of critical process parameters, such as pressure, temperature, flow rate, to enable operators to optimize plant operation from the central control room.

Or as Guanlao articulates: "We are now able to troubleshoot the operation. If something is wrong you know about it straight away just by looking at the Operator screen. You don't have to go down, climb on top of a tank or go around collecting lots of data and in the process potentially waste tonnes of oil while you're diagnosing and rectifying the problem. Having that information right before you has really been the number one benefit, I believe." Moving away from a manual operation has also enabled a much smoother and predictable production output, as opposed to the rather wild swings that were happening before. And as well as quantity, consistency has also been noted in the quality of oils produced at the end of the line.

Rapid returns
That all sounds good but how does it translate to dollars and cents for Oleo-Fats? Well, pretty well, according to the plant manager.

"We invested almost 12 million pesos into automating PRP 3 and PRP 5. And we were able to recuperate this amount within just nine months through greater product consistency and less plant downtime. That kind of rapid return on investment was a main reason why we so were keen to push for automation in the other physical refining plants," he says.

As for the relationship between client and automation vendor, Gerry Guanlao points to Siemens providing ready and quick response through the various project stages. Siemens was also on site to provide training on aspects such as programming and system maintenance. The latter can now be performed by Oleo-Fats' own staff while Siemens is called in when there are "additional requirements, tweaks or some configuration to be done".

Quizzed on future plans in terms of automation technology, Guanlao is already starting to think in terms of the MES layer, i.e. implementing a manufacturing execution system to provide a level of management information. "Then at the end of the shift, you can know how much you produced and how much it cost to produce. Was it over or under? That should be our next step."