Léon, Mexico, is an industrial city 400 km north of Mexico City with approximately 1 million inhabitants. It's considered to be the world capital of leather and shoe production. Many worldwide brands such as Adidas and Nike have their products made in its 600 tanneries and 1000 shoe and leather factories, generating tons of wastewater.
Tannery wastewater requires special treatment. Beside organic tanning agents, wastewater from the factories may also contain salts and metals, such as chrome, zirconium, aluminium, titanium and iron, together with synthetic tanning agents such as formaldehyde and phenols.
The original wastewater treatment plant in Léon was previously also used for tannery wastewater, but in the long term proved insufficient for the needs of the developing industrial city. Tannery waste is toxic to most of the facultative bacteria necessary to operate a conventional secondary wastewater treatment facility, so an industrial wastewater treatment plant was needed.
Fypasa and Festo
Fypasa is an engineer-constructor-operator of wastewater treatment plants in Mexico. Fypasa has been building and operating wastewater treatment plants throughout Mexico since 1969 and, therefore, has a great deal of experience as a plant builder. As a plant operator, the company treats 40% of all wastewater in Mexico. The Léon industrial wastewater treatment plant, which Fypasa built in 2009 and has operated ever since, supplements the original treatment plant, which was originally designed for household wastewater. Fypasa understands the construction, operation and maintenance of wastewater plants.
"But, as we are not specialists in plant automation, we rely on the experience of Festo's project engineers," explains Mauricio Plascencia, operations manager of the Fypasa treatment plant in León.
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Festo as System Integrator
Festo, a German company devoted to specialized automation components, developed a complete solution, covering everything from the sensor/actuator level through to the field level, individual control level and process control level, including a SCADA process visualization system. Some of the products were of Festo's manufacture, but many were not.
"Starting with the engineering phase, we supplied Fypasa with a suitable automation concept, including circuit diagrams, CAD data and 3D models of the process valves and control cabinets, central components of the sensor/actuator and field levels, so that they could be included in the designs as ready-to-install units," says Eduardo Poupard, project engineer with Festo Mexico.
Festo was able to demonstrate to Fypasa that it had sufficient experience and understanding of the processes involved in a wastewater treatment plant to develop a solution that meshed perfectly with the plant design.
Festo engineers managed the entire automation project for Fypasa. They handled the purchasing phase with activity charts, definitions of milestones and the punctual delivery of subsystems. The installation phase was simplified by Festo's performing factory acceptance tests (FAT) with simulation tests of the process valves and the control cabinets in the Festo Test Center. Festo also produced the product documentation and completed the installation of subsystems throughout the plant. "This made it easy for us at Fypasa to concentrate fully on our core competencies," Plascencia says. During the commissioning phase, the Festo project engineers conducted site acceptance and process tests (SAT) for each unit within the plant.
How the System Functions
"At the individual control and process control level, the master controller PLC CECX-X-C1 from Festo acts as a programmable logic controller," Poupard says. "It feeds data to the SCADA software VipWin to allow process visualization. CPX/MPA valve terminals gather the input and output signals, feed these to the master PLC and activate the pneumatic actuators. These are installed in seven control cabinets for protection. The automation platform CPX also provides functions for remote maintenance, remote diagnostics, a web server, text messages and an email alarm."
The two fermentation towers are equipped with two types of process valves: gate valves for the sludge inlet and butterfly valves for the fermentation gas discharge. The pneumatic actuators used at the sensor/actuator level to open and close the process valves have significant advantages over electrical installations: durability, long service intervals and safety under overload conditions.
"What is more," Poupard says, "because of the intrinsic simplicity of pneumatics, the system is easier to maintain, saves costs and increases efficiency as staff require little training to work with the pneumatic system."
Similarly, right from the time of its foundimng more than 300 years ago, St. Petersburg has set standards in architecture and city planning. Now this city, the former capital of Russia, is playing a leading role in the field of drinking water treatment.
Vodokanal, the St. Petersburg water utility company, has set itself the target of reducing the electricity consumption of its drinking water supply system by more than a third. Until now, electric drives were the first choice for Russia's water treatment plants, but in St. Petersburg, the use of only electric drives would have meant an installed load of 75 kW. The plant could not have provided this without extending the electrical infrastructure. "In order to achieve the energy-saving targets which we set ourselves, we therefore needed to find new solutions," explains Maksim Pirschin, manager of the plant's block K-6 at Vodokanal. A pneumatic system required an installed load of only 10 kW. "Simply by replacing the electric drives with 120 pneumatic actuators from Festo, we were able to save at least an additional €65,000," said Pirschin.
The new block K-6 of Surface Water Treatment Plant South in St. Petersburg includes 20 new sand filters. Each filter basin is assigned six butterfly valves with actuators and shutoff valves to open and close the facility's inlets and outlets.
In addition to valve assemblies consisting of butterfly valves with actuators, shut-off valves and sensor boxes, which Festo supplied in ready-to-install form, Vodokanal has chosen ready-to-install control cabinets with VTSA valve terminals, pressure and flow sensors and service units from Festo's MS series. "If we source all the pneumatic automation equipment we need from the same supplier, we simply have fewer problems during operation and maintenance," Pirschin adds.
Running with the Big Dogs
Craig Correia, manager of process automation at Festo USA, says, "We're looking for applications where we can win. We can't really compete across the board with the big automation vendor companies, but we've been successfully leveraging our strengths in water treatment, the chemical industry, and in wastewater treatment. We have innovative offerings in process valves, actuators, pneumatic actuators and I/O."
He went on to explain that the expansion of Festo into system integration has been successful. "As you've seen from these examples, we can do the complete automation for small- and medium-sized projects where we supply the valves, the actuators, and we also design the control system, provide the GUI and build the cabinets. We love to be sole source, and we make sure we give our customers the value that sole source deserves."
Standardization of Automation
Likewise, B. Braun Melsungen AG has Europe's most modern manufacturing plant for infusion solutions. A comprehensive analysis of automation technology requirements by experts from Festo and B. Braun found that the entire value chain could benefit from standardized pneumatic automation components. "The reduction of maintenance costs and the decrease of downtimes were the most persuasive arguments for standardization," explains Klaus Sonntag, head of maintenance with B. Braun.
The life nutrition plant in the new B. Braun factory produces infusion solutions in new, three-chambered bags and is highly automated, but now also highly standardized. Standardization revealed an enormous potential for improvement in both the primary and secondary production areas. Previously, the various plant and machine builders supplying production and packaging equipment had installed automation products sourced from up to six different pneumatics suppliers. This required a large number of spare parts, which increased complexity and thus the costs of maintenance.
Standardization Decreases Complexity
The project's aim was very clear: as many machines and installations as possible were to be equipped with the types of pneumatic components previously used at B. Braun. The project team defined a standard and produced a list of recommended equipment that considerably simplified maintenance work at B. Braun. In this engineering phase, the Festo experts provided much advice, covering everything from a 3D model to design coordination.
During the logistics and implementation phase, the automation specialist coordinated the implementation of standards with the various machine and plant builders. This made it possible to achieve a single-source supply chain, which cut costs and increased the efficiency of the purchasing process. In this phase of the value chain, Festo planned, built and supplied 45 ready-to-install valve terminal cabinets directly to the pharmaceutical plant manufacturer.
Simply Fit and Forget
Complete solutions were supplied fully assembled and tested, thus reducing the workload of the customer's technical personnel, keeping system design costs low, simplifying the purchasing process and cutting process costs. "Fit and forget is the objective for our customers," explains Jürgen Weber, head of key account management for process automation at Festo Germany. This generates clear advantages for users in the installation and commissioning phase.
B. Braun can rely on uniform product technology, from the process installations to the packaging machines. At the heart of the automation system at the sensor/actuator level is the valve terminal CPX/MPA, installed in a control cabinet. Thanks to its flexible control concept, the bus-driven valve terminal can be used as an I/O module for the connection of all feedback signal devices, drives and process valves. Today it's controlling 4000 diaphragm and other process valves in pharmaceutical production operations. Festo was able to guarantee that all the deliveries from the various countries conformed to the project standard.