News
Read articles and the latest industry news from ProChem.



 

One of our company values is to protect people and the environment. We seek to do this through partnering with industrial plants to help them safely reuse water and discharge wastewater, reducing the burden on local water utilities. We take pride in using chemicals and processes that aren’t harmful to the environment or to people. Based in beautiful Southwest Virginia, we understand how sensitive our lands and waterways are to misuse and pollution.

On Sunday, July 15, 2018, the Roanoke Times published an article (and later a follow-up) about discoloration in the James River due to a waste treatment issue at a paper mill in Covington, Virginia. Of course, any change to sensitive river ecosystems is a potential cause for concern, but we also think it’s important to understand the severity of those changes.

Paper mills use millions of gallons of water a day and often discharge their wastewater into local waterways, since water utilities wouldn’t be able to handle such an influx. One way they can mitigate the risks of water discoloration and other related issues is to treat and reuse a majority of their water. By integrating an industrial water reuse system, 85% to 90% of their water could be reused, while treating and discharging only 10% to 15% of their daily intake.

While we don’t work with the paper mill mentioned in the article, we do partner with wood industry plants. (In fact, we recently published an article about one such customer.) The water they use to scrub fine wood particles from gases before they can be released into the atmosphere (to comply with EPA regulations) is exceptionally dirty. Tar and lignin, which caused the discoloration in the James, are unavoidable byproducts when working with wood. And they’re very difficult to clean from water. We spend a great deal of time and effort developing the most effective chemistry and systems to do so safely and within discharge limits.

So, what happens when those discharge limits are exceeded? If it’s a hazardous substance, the results could be catastrophic to people and the environment. Fortunately, that didn’t happen this time. Lignin is a natural substance found in the cells walls of plants. It’s separated from wood during the chemical process of forming wood pulp. While unfortunate, the one-time release of an excessive amount of lignin into the James was not on the scale of a “hazardous spill.” Likewise, the accidental release of biodegradable defoamer (probably a mineral oil-based one) should not be a cause for concern.

It’s important to keep an eye on industry and to advocate for greater water reuse and the rigorous application of discharge limits. Better water management policies are needed to prevent pollution and to preserve our supply of fresh water. Water reuse and treatment technologies like the ones we develop are important in this effort.

 

Further reading:

Wood Products Industry - Benefits of Reusing Process Water

CleanWESP Saves Maintenance Costs and Down Time

CleanWESP Extends RTO Media Life

What the Engineered Wood & Pellets Industry Does with Their Water

ProChem recently completed another project that embodies our mission: to advance our customers’ total water management strategies by providing innovative solutions supported by a comprehensive set of services. This project required the coordination of chemistry, equipment, technology, and customer-centered collaboration—all the disciplines on which ProChem was founded and continues to operate.

 

The Customer

Prior to finding ProChem, this wood products manufacturer had been working with their local publicly owned treatment works (POTW) to treat their water. They needed to lighten their heavily pigmented water so that it could be penetrated with a UV light in order to disinfect it before discharging to the POTW.

The company initially hired an engineering firm to find a solution, but because there are so many nuances in waste water treatment that require expertise in multiple disciplines, they were unable to provide one. They would have needed to understand the wastewater, the chemistry, and the unique needs of the customer—a specialized set of services they turned to us to provide.

The plant’s wastewater comes from their wet electrostatic precipitator (WESP) system, which uses water and electricity to scrub fine wood particles from gases before they can be released into the atmosphere according to EPA regulation. Those fine wood particles end up in the wastewater that the ProChem system needed to treat. Our starting point was our CleanWESP water treatment program, designed by ProChem chemists specifically for the wood products industry to protect valuable equipment such as the WESP. Even with this solution in place, this customer had significant problems that would require some creative problem-solving. Fortunately, our team lives by the premise, “The bigger the problem, the bigger the solution.”

While ProChem’s experts were researching the problem, the POTW continued to tighten their restrictions. As a result, the scope of the project pivoted from merely lightening the pigmented water for discharge to treating and reusing 10% of their wastewater inside the plant. This is what we refer to as a “kidney loop”—continuously treating part of the stream, rather than the whole thing, to keep the whole stream cleaner. 

ProChem’s custom-tailored solution to treating wastewater for discharge while also implementing water reuse required a carefully orchestrated combination of chemistry, equipment, and technology.

 

The Chemistry

 

When dealing with wood wastewater, there’s only one proven chemical treatment that works. A coagulant turns dissolved contaminants into solid particles, while the polymer holds those together to make bigger particles, which typically sink to the bottom. But in cases such as this, the wood particles float. The chemistry team at ProChem had to find a combination of polyamene, pH, coagulant, and polymer that had good separation to allow the solids to float in as compact a layer as possible and also produce water as clear as possible. At the plant, the particles on the top get skimmed off and go to the belt press, where the water in the sludge is removed and the sludge is disposed of.

 

The Equipment

 3 Conex Water Reuse System: Sand filtration, IPro, BPro

The system that ProChem designed includes pretreatment, sand filtration, reverse osmosis membrane filtration, and UV lights. The system is based around a specialized chemical treatment program coupled with I-PRO™ and B-PRO™ membrane technologies. Designed to treat up to 60,000 gallons per day at 200 gallons per minute (gpm), the current system handles 125 gpm of reuse water and is integrated with existing clarifiers, dissolved air flotation (DAF), and a belt press.

ProChem fabricators constructed three Conex containers at our facility in Elliston, Virginia, and outfitted them with amenities for 24-hour, year-round operation—lights, heaters, fans, and ventilation.

One container houses three 62-ft3 sand filters operating in parallel with one in service at a time. The sand filters are equipped with automatic switching and backwashing of exhausted columns using permeate water.

Our membrane technology for this project included both I-PRO and B-PRO Conex containers. Both containers consist of an automatic prefilter switching to reduce down time, additional chemistry to prevent scaling and biological growth, and an automatic phase change based on conductivity—keeping discharge within operating parameters. The I-PRO container consists of 10 membrane housings, each with six membranes, while the B-PRO container has eight membrane housings with four membranes in each.

As always, we incorporated the most up-to-date technology that was appropriate for the customer’s particular needs:

  • High-efficiency booster for maximum reuse
  • 125-hp motor and operating pressure, producing approximately 700 psi to 900 psi in the I-PRO
  • 50-hp motor with an operating pressure between 300 psi and 400psi

The initial walkthrough at the customer’s plant revealed tight spaces that would require precise piping work to create the most efficient and sustainable system. For a clean piping sequence, our Project Superintendent made sure there were no “jumping pipes,” meaning no pipes overlap. Overlapping diagonal pipes make the system less serviceable. For example, simply fixing a valve could require cutting pipes. Because of our close attention to detail, that wouldn’t be necessary for this project.

 

The Technology

 

This system is automated and continuously transmits data to ProChem’s AutoRun™ software. To accomplish this, our Controls & Instrumentation Engineer used the P&ID to determine how many PLC (programmable logic controller) inputs and outputs would be needed. The PLC is at the center of the control system, continuously monitoring the state of input devices and making decisions based upon a custom program to control the state of output devices as much as 100 times a second.

Our Controls & Instrumentation Engineer writes custom programs using algorithms to monitor flow, dose chemicals, adjust pH, control agitator speed, and much more. Any signal that can be measured can also be manipulated.

ProChem upgraded the customer’s wastewater treatment system to provide operators the means to enhance their process for meeting the plant’s water quality needs. As part of the upgrades, ProChem modernized the control system utilizing a Remote I/O solution. This technology reduced wiring costs while improving operational readiness and reliability.

The Remote I/O system provides a reliable method to transfer monitoring and control signals to and from the PLC-based control system. In this configuration, two Remote I/O stations are situated along the Ethernet network in different areas of the system. Each station contains five to 10 I/O modules. For monitoring applications, the system collects signals from analog transmitters or discrete devices. It concentrates the signals and, when polled by the network master, sends them over the Ethernet network directly to the main PLC control panel. For control, process commands from the host are transmitted over the network and converted to analog or discrete form to control valves, pumps, motors, and other types of proportional and on/off control elements.

 

The Takeaway

This wood products manufacturer has a large and complex treatment system with multiple moving parts. The challenge for us was to make all those parts work together in balance. It was the most complicated control system our engineers have ever designed.

As always, we maintain an ongoing relationship with this customer and continue supporting them both remotely and on-site. In fact, one of our Environmental Technicians is responsible for the day-to-day optimization of the system.

ProChem’s team took a customer who was discouraged and gave them the solution they needed to protect their costly (about $1 million/year) WESP equipment by treating and reusing their wastewater. The remaining wastewater is discharged to the POTW, guaranteed to maintain compliance.


Looking for a solution to your industrial water problems? Contact our experts today!

 

On June 28, we shipped a trailer-mounted pilot system to a customer in Indiana. The on-site pilot system will operate for several weeks, demonstrating how the full-scale process would work. The system is designed to treat flue gas desulfurization (FGD) wastewater to meet Effluent Limitations Guidelines (ELG) limits. The technology components featured on this pilot system include:

  • ProChem’s I-PRO™ industrial high-pressure reverse osmosis unit
  • ProChem’s I-Micro™ microfiltration system
  • Membrane clean-in-place system

 

The 40-foot conex container also includes a laboratory area for process water testing, jar testing, and analysis of treated water, as well as a control area including HMI and SCADA monitors to allow for continuous monitoring and control of all process systems. Before the pilot system left ProChem’s headquarters, our Water Systems team put it through its paces to ensure safety, quality, and ease of installation at the customer site.

ProChem provides on-site pilot testing to demonstrate a treatment program’s performance in a live environment. Pilot tests provide an opportunity to optimize and enhance the performance of the program on site, so that our customers are confident that what they purchase meets their goals. 

ProChem provides on-site pilot testing to demonstrate a treatment program’s performance in a live environment. Pilot tests provide an opportunity to optimize and enhance the performance of the program on site, so that our customers are confident that what they purchase meets their goals.

Recently, we sent a pilot system to Reno, Nevada, where it demonstrated how the full-scale process will facilitate physical/chemical treatment of the facility’s wastewater, followed by microfiltration (I-Micro™) in advance of an industrial high-pressure reverse osmosis (I-PRO™) system. ProChem operators took turns around-the-clock to ensure safety, quality, and ease of use at the customer site. The pilot system is simple to install using feed connections for the facility wastewater it will treat. It comes complete with operations documentation and log forms for test data collection. The technology components featured on this pilot system include:

  • ProChem’s I-PRO, high-pressure Reverse Osmosis unit
  • Chemical feed system and conical bottom feed tank
  • Membrane clean-in-place system

 

ProChem provides on-site pilot testing to demonstrate a treatment program’s performance in a live environment. Pilot tests provide an opportunity to optimize and enhance the performance of the program on site, so that our customers are confident that what they purchase meets their goals. We recently designed a compact and fully loaded pilot system that will operate at a customer site for several weeks to demonstrate how the full-scale process would work, removing up to 99.5% of dissolved salts and virtually all colloidal and suspended matter from their water source.

The system will produce a high-quality water yield at a low cost compared to other purification processes. Before the pilot system leaves ProChem's warehouse, our Water Systems team is putting it through its paces to ensure safety, quality, and ease of installation at the customer site. The pilot system is simple to install using feed connections for the city water it will treat. It comes complete with operations documentation and log forms for test data collection. The technology components featured on this pilot system include:

  • ProChem’s I-PRO, high-pressure Reverse Osmosis unit
  • Chemical feed system and conical bottom feed tank
  • Membrane clean-in-place system

The whole system is only 65" tall x 54" long x 36" deep. That's a lot of technology packed into a neat little package.