We tend to think about it only when disturbances occur, but wastewater treatment is a basic public service that affects all of us:

it is vital to keep our living environment hygienic and healthy and our watercourses clean. Behind the scene, the wastewater treatment process combines microbiology and chemistry with mechanical engineering, instrumentation, and automation techniques that offer high performance in a progressive way.
  
 Industrial wastewater treatment
 The central wastewater treatment plant of a Finnish company receives household and industrial wastewater from different communities and utilities. "Around 60 percent of the water treated here is industrial wastewater," said the plant’s operating chief. Treatment of sewage including animal waste is especially laborious. "Compared to industrial sewage, we consider household wastewater to be clean enough to be used as a drink," he jokes. The automation of the whole system has to be considered with care.
  
 

Part of the company’s work involves maintaining central wastewater treatment plant in a nearby city. This is where the automation system had to be renewed.

An accurately controlled process
 The process starts with the primary treatment, where the influent sewage water is strained to remove all large objects and the oxygen level of the water is increased to facilitate microbe activities (microbes clean the water by feeding on its impurities). During this biological treatment phase, the microbes in the wastewater are given suitable growing conditions in terms of temperature, oxygen level, and nutrition.

The next phase includes chemical secondary sedimentation, where aluminum-based chemicals are added to the water from the biological treatment to prompt flocculation of slowly-degrading organic and other materials. In the last phase, the remaining sludge is treated by removing water from it. The water separated from the sludge is taken back to the beginning of the treatment process, and the solid sludge is taken to the biogas plant.
High-tech automation system
The central wastewater treatment plant is fully automated. The automation system from 1992 reached the end of the road. Requirements for the technology selected to renew the wastewater treatment plant were:

• Ease of installation and maintenance
• Flexibility to adapt to fast-changing regulation
• Improvement of the overall solution
• Compliance with existing applications and methodologies

 
 The whole system was renewed in 2008 in collaboration with Schneider Electric®. “The old automation system had served its time. We have been using it every day for the past 16 years," the operating chief explained. The original automation system involved six controllers from the TSX7 series, with Monitor 77/2 software environment, and used MAPWAY communication protocol. In the new solution, six Modicon® Premium™ controllers are implemented with Monitor Pro v7.6 and are using Modbus® TCP/IP over wireless, using nine of ProSoft Technology's industrial radios. About 2000 process variables are transiting over the wireless network, which is also used for programming and maintenance purposes.
 

Why wireless? 
 A total of seven locations had to be integrated into one single tight network. The 6 Modicon Premium controllers are located in different buildings at the wastewater treatment plant, and the plant has two control rooms. "We put the second computer here in this higher building so that our feet never get wet," the operating chief said. The plant is situated in an area prone to flooding. Of course, the plant can continue to operate even if the computers are down.

From the user point of view, the first advantage of the wireless networking option was the cost and time savings for the installation: no need to dig tranches, and no need to clean up existing cable paths.

From the integrator’s point of view, the wireless network was "the easiest part of the implementation. We didn't have any problems. These radios are very easy to configure, and mounting recommendations given by ProSoft Technology were very clear. Schneider Electric made some tests in their office and then explained to us how to implement the wireless network on the field."

From Schneider Electric’s point of view, the engineering of the network was reduced to a minimum. "When we started the project, we did not locally have any specific RF expertise," explains the then-Application Sales and Key Account Manager, Wood and BioEnergy, at Schneider Electric Finland. "We talked to ProSoft Technology Technical Support Engineers and provided them with the basic engineering and layout of the network. They made some calculations that where necessary for this type of application and they provided us with the recommended lists of accessories for each radio location: cables, antenna, lightning protector, etc. They also provided all the necessary recommendations for mounting and implementation in the field. The wireless network implementation was an easy job for us and our integrator.”

Long term investments 
"The controls have been defined largely in the same way as in the old system," the plant’s operating chief explained. "Some of the old controls have remained the same, some have been added, and we have changed the commands a little bit." Since 1992, the plant has acquired a new sludge drying centrifuge and the treatment process has been modified by a new chemical treatment with aluminum. The automation system had to evolve accordingly.

"No controller can remain the same forever. There are always some additions and changes along the way. In this industry in particular, the regulations change quite a lot over the years as well," said the Schneider Electric sales manager, who took part in the plant’s original automation project in 1992.

The new setup is working well.

"We have not had any problems with the implementation of the new automation system. The graphics of the user interface have remained practically the same so we are familiar with the screens and don't need additional training," the plant’s operating chief said.

The reporting program in use is separate from the SCADA, but it reads data directly from the Modicon Premium controllers as well, via the same network.

In the future, the controllers can be easily modified or complemented when necessary with additional input or output modules. On the network side, the wireless option provides an additional degree of flexibility.

Learn more about ProSoft Technology’s Industrial Wireless Solutions here.

A major company known for engineering, building, and managing water treatment plants was faced with a new challenge.

At a French treatment facility designed by the company, an innovative method was implemented for a common wastewater treatment application involving sludge drying.

The sludge drying process is a residual element of the application that takes place once water has been cleaned and decanted.

 Radios and robots

In the solar sludge drying process developed by a subsidiary of the manufacturer, sludge is treated by a centrifuge and laid out in windrows in a greenhouse heated by solar radiation. An automated robotic turner is used to aerate the sludge and accelerate water evaporation. The robots are radio-controlled, which provides a more robust solution than the traditional wired approach. With wireless control of the robots, the entire operation is automated, and there is no further need for operators to enter the greenhouse.
  
The company decided to attach radios to the robots to enable information to be sent to and from the control station. This means the operator can control the robot remotely, program its movements, and know its current position. The robot has an onboard controller that interfaces with the radio.

“Implementation proved to be very simple, thanks in particular to ProSoft Technology’s technical support,” explained a representative of the system integrator. “As far as the choice of supplier was concerned, we stuck to the specifications given by RG2I, their local distributor. Our major concern was reliability. We had to have a reliable solution, with none of our users encountering any problems. This is indeed the case with ProSoft Technology´s wireless solution.”
  
So far, ProSoft Technology radios have been installed at half a dozen of the company´s sites.

A reliable transmission system

The wireless solution brought all of the advantages of wireless connection to industrial automation applications, while still offering high levels of reliability. In addition to its ability to withstand harsh operating conditions, it also improves the transmission of Ethernet data packets.

The standards set out in IEEE 802.11 (commonly known as “Wi-Fi”) bring an extremely high level of security, flexibility, and interoperability to industrial automation applications. Originally designed for office and home applications, these less-robust technologies have limitations when it comes to industrial protocol transfer, resulting in transmission problems for industrial automation systems associated with the radio transmission method used for Ethernet packets. But ProSoft’s wireless solutions ensure optimal transfer of data packets. To improve data packet transfer, the radios use a specific signal processing algorithm implemented by ProSoft Technology, which allows better use of the full bandwidth and supports the fast data transmission speeds demanded by industrial automation engineers. This is particularly vital for industrial applications (involving protocols such as EtherNet/IP™) with a need to transport non-critical messaging data but also critical industrial I/O data.
  
With its “Power over Ethernet” (PoE) specification, the power supply and connection of the radio system to the wired Ethernet is done via a single cable (instead of two), which greatly simplifies installation and reduces set-up times. Another valuable function of the wireless solution is that it supports serial encapsulation, which means that serial peripherals can be used and integrated into the main Ethernet architecture of the control system. The radio used in this application ensures high performance for both 2.4 GHz and 5 GHz band configurations.
  
These wireless solutions are ideal for industrial applications: industrial grade enclosures, extended operating temperature ranges, compliance with shock and vibration resistance standards, certification for use on sites where there is a risk of explosion, fitting to DIN rails, and more. These factors were important to the system integrator in their decision to select a ProSoft wireless solution for their application.

To learn more about ProSoft Technology’s Wireless Solutions, click here.

Renewable energy is the way of the future. We see hydropower towers on river beds, wind farms on hillsides, and solar panels on rooftops. Now a company in Pennsylvania has perfected a way to produce biogas, or a gas fuel derived from the decay of organic matter, by extracting methane from decomposing landfill waste and supplying it to customers as an alternative “greenhouse” fuel.

Unharnessed, methane is one of the most potent greenhouse gases. The end user’s project uses wells to both oxygenate the waste mass — expediting the decomposition process — and to trap the raw biogas before it can escape into the atmosphere. Separators are then used to clean the gas by extracting methane from the remaining gas substance (composed of carbon dioxide and trace elements) for use as a natural gas alternative.

The whole process creates a symbiotic eco-relationship between waste and energy by aiding in the waste degradation process; repurposing methane that would have otherwise been emitted into the atmosphere; providing a less expensive form of energy to the world; and providing an alternative to less eco-friendly options.

Biogas Distribution

One of the company’s biggest customers, a major international food supplier, uses the green energy as a natural gas substitute to power the boilers that keep its entire plant operating. Because the biogas supplied by the company is approximately half the cost of natural gas, the customer is able to significantly decrease their power costs without much of an upfront investment. To utilize the company’s biogas product, the customer had to customize their boiler system, but that required little more than increasing pipe sizes and installing an alternate piping system to be used in lieu of their natural gas or fuel supply.

“It’s just another supply link that has to be put in and retrofitted into the existing scheme of things. This cost is recouped quickly by the savings they receive from our program,” said an electrical engineer with the biogas-production company.

Monitoring Consumption

The plant is relatively large and spread out, with metering panels located throughout the various buildings on site to track the amount of gas used. Inside each of the three panels is a Rockwell Automation® CompactLogix™ PAC, which monitors gas flow variables to measure consumption at the facility.

To connect the biogas company’s main facility to its customers, a T1 hardwired phone line is used. The next decision was how to link up the end of the phone line at the customer site to the three PACs.

“Because the plants are so spread out, we opted to use wireless at those points to save on installation. We just needed to find a product that is robust and easy to implement,” the electrical engineer said. ProSoft Technology’s water- and dust-tight Industrial Hotspot radios were selected.

“We use CAT-5 cable and Power over Ethernet (PoE) for both power supply to the radio and communication between the radio and the PAC. PoE allows us to plug the radios right into our PACs, plus the casing allows them to be mounted outside without weather concerns,” the engineer said.

The Result: A Fully Automated System

The T1 connection links the plant back to a master PAC in the biogas company’s main plant, which is constantly pulling meter data from the remote customer sites and feeding the information up the chain to corporate for billing.

The bandwidth allows them to see things in real-time, and is entirely automated so there is no need to go onsite at the customer’s facility to collect meter information.

“The radios are great. They saved us on installation and simplified implementation. I would recommend them to anyone,” the engineer said. “My ProSoft sales representative was incredibly helpful, involved in the process, and knowledgeable on the technology and application. He deserves kudos.”

Benefits

The biogas company is a carbon-negative facility. They convert their own product onsite into electricity using an electrical generator to run their facility, so they are entirely self-sustained. The balance of remaining unused electricity is sold to the local utilities company, reducing dependency on fossil fuels.

The food manufacturer can feel good too. By using repurposed methane, the highly potent greenhouse gas was not emitted into the atmosphere.

“Landfill-gas-to-energy is not just an environmentally responsible choice, it makes sense financially,” the biogas company’s engineer said. “Another one of our customers was able to save enough money using our natural gas substitute to add a third shift during the week and schedule weekends into production. The extra shifts mean extra jobs. It’s a nice feeling.”

Learn more about ProSoft Technology’s Industrial Wireless Solutions here.

An average person turns on his TV set with the simple push of a remote, after turning on the light in the kitchen, and grabbing a cold sandwich from the refrigerator.  Most people don’t think of where the electricity powering their light bulb, refrigerator, or TV is coming from, or the processes involved in producing the electricity.

Ships dock continually each day at the Gwangyang Harbor adjacent to South Korea’s Hadong Power Plant, transferring tons and tons of coal. Bucket after bucket carrying tons of coal from each carrier ship’s cargo area is then transferred via a conveyor that leads to the coal testing and analysis process, which is a very important part of the power plant’s operation.

Rocks of bituminous coal are measured for quality, a determinant of whether it is good fuel or not. Coal quality determines whether it will burn effectively, therefore generating maximum electricity and reducing plant maintenance.  The fewer impurities in the coal, the better it burns in the boiler. Impurities include ash, phosphorous, sodium, sulfur, and more, which can also cause problems with the coal plant’s boiler system.

“This processing is very important. It works to capture coal samples before they are input into the boiler,” said Kyungkoo Cho, Deputy General Manager for distributor Ajin Systech. 

The Hadong Power Plant, operated by Korea Electric Power Company, produces 6 percent of South Korea’s electrical supply, making it a vital source of energy in the country that produces many of the world’s consumer electronics from companies such as LG and Samsung.

Construction of the plant began in 1993, with the first two coal units producing power. In subsequent years, six units have been added to the plant.

In 2009, power plant engineers faced a challenging decision. Should they lay more than 600 meters of costly fiber optic cable at the plant’s coal handling and testing area, or ditch the wire and use industrial hotspot radios? The solution was simple: Industrial wireless radios were surely the way to go in this aspect. Meters and meters of fiber optic cable would have been costly, and likely would have been time-consuming.

With wireless, there were concerns about signal strength around the plant. There had to be a good connection between each area of the wireless system. ProSoft Technology provided a cost-effective, strong signal solution for the Hadong Power Plant.

With ProSoft Technology’s Industrial Hotspots, the solution turned out to be an easy one for Ajin Systech, a South Korea distributor contacted by the power company.

“ProSoft Technology’s wireless technical solution is stronger than other radio makers in terms of long distance,” Cho said.

In the coal handling testing and analysis process, a ControlLogix® PLC is connected to a FLEX™ I/O system at remote coal handling stations, which are used for testing and analysis purposes. ProSoft radios are installed on the conveyor tower, which controls the buckets moving and discharging the coal and the Master ControlLogix.

Data is consistently and securely transferred between the radios. Plant engineers know at any minute whether the bucket and conveyor system transferring the coal that keeps the plant operational is moving smoothly, as ship after ship unloads valuable cargo. The coal is then input into the boilers, where the energy is converted into steam, passing through a turbine that generates the electricity that is added to the country’s power grid.

The person continues to watch the TV and eat his cold sandwich, as the compact fluorescent lamp above keeps the room bright. And it all started at a power plant somewhere, possibly with the unloading of coal from a bucket to a conveyor.

To learn more about ProSoft Technology’s Wireless Solutions, click  here.