Hi Pro Equipment Inc. has received the 2021 Merwin Award, according to an announcement made by Eriez USA Senior Sales Director Dave Heubel. The annual award is given to an Eriez representative firm for outstanding contributions in sales performance and customer service and support.

Hi Pro Equipment, based in Kalamazoo, Michigan, has represented Erie, Pennsylvania-based Eriez for 21 years. The firm is now a three-time recipient of the Merwin Award, with previous wins in 2012 and 2017.   

Hi Pro Equipment is a manufacturers’ representative of bulk material handling equipment. The offers complete systems, custom designs and components for various process industries. Hi Pro serves a diverse range of industries, including agriculture, automotive, chemical, food, minerals processing, mining, pharmaceutical, plastics, recycling, wastewater, original equipment manufacturer, metals, glass and paper/wood.

“The Hi Pro sales team had an exceptional 2021, exceeding goals in all assigned markets, all assigned products and setting a new territory record for overall order performance,” Heubel says. “Since 2001, Hi Pro has represented Eriez with remarkable technical skills, professionalism and integrity, ensuring our mutual customers have a top-notch experience before and after the sale.” 

The Hi Pro team includes Russ Campbell, Randy Klinger and Justin Story.

To commemorate this accomplishment, Hi Pro will receive a framed Merwin Award and the company’s name will be inscribed on the Merwin Award plaque which is on permanent display at Eriez headquarters. 

Eriez magnetic separation, metal detection, material handling, fluid recycling and advanced flotation technologies have applications in the mining, processing, packaging, food, recycling, aggregate, plastics and metalworking industries.

Lake Forest, Illinois-based Packaging Corp. of America (PCA) has reported year-end figures for 2021 that include increases in net sales and earnings before interest, taxes, depreciation and amortization (EBITDA).

On the sales front, the company’s $7.73 in 2021 sales represents a 13.9 percent increase over $6.66 billion in 2020. PCA’s 2021 EBITDA of more than $1.66 billion was a 35.9 percent rise from a 2020 figure of $1.23 billion.

The company enjoyed a profitable fourth quarter despite that time period including “certain costs at the Jackson, Alabama, mill for paper-to-containerboard conversion-related activities.” PCA says fourth-quarter market and financial conditions included “higher volumes and higher prices and mix in our Packaging and Paper segments, lower wood fiber and energy costs, lower scheduled maintenance outage expenses and a favorable tax rate.”

Mark W. Kowlzan, chair and CEO of PCA, comments, “Demand in our Packaging segment remained very strong, with our corrugated products plants delivering record fourth-quarter total shipments and all-time record shipments per day that exceeded last year’s extremely strong fourth quarter. We utilized the capability of both machines at our Jackson, Alabama, mill to produce containerboard for the entire quarter, yet inventories, including the additional containerboard inventory from our December acquisition of Advance Packaging, moved lower from the end of September.”

Continues Kowlzan, “Looking ahead as we move from the fourth and into the first quarter, in our Packaging segment we expect to benefit from higher corrugated products shipments with three additional shipping days, and we expect shipments per day to be higher than last year’s first quarter as demand remains strong, along with slightly higher domestic and export prices and mix. Additionally, in our Paper segment, we expect higher prices and mix from our previously announced price increase that was implemented beginning last November.”

The United States Environmental Protection Agency (EPA) has announced the addition of four per- and polyfluoroalkyl substances (PFAS) to the Toxics Release Inventory (TRI). The EPA included the additions as part of its "Strategic Roadmap" to confront the human health and environmental risks of PFAS.

TRI data is reported to the EPA annually by facilities in certain industry sectors, including federal facilities, that manufacture, process or otherwise use TRI-listed chemicals above certain quantities. The data include quantities of chemicals that were released into the environment or otherwise managed as waste. Information collected through the TRI allows communities to learn how facilities in their area are managing listed chemicals. The data collected also help inform the EPA’s efforts to better understand the listed substances.

“We will use every tool in our toolbox to protect our communities from PFAS pollution,” says Michal Freedhoff, assistant administrator for the Office of Chemical Safety and Pollution Prevention. “Requiring companies to report on how these PFAS are being managed, recycled or released is an important part of EPA’s comprehensive plan to fill critical data gaps for these chemicals and take meaningful action to safeguard communities from PFAS.”

The four PFAS added to required reporting include perfluorobutane sulfonic acid (PFBS), potassium perfluorobutane sulfonate, perfluorononanoic acid (CASRN) 65104-45-2 and CASRN 203743-03-7. PFBS-based compounds are replacement chemicals for perfluorooctane sulfonate, a chemical that was voluntarily phased out by the primary U.S. manufacturer by 2002. PFBS have been identified in the environment and consumer products, including surface water, wastewater, drinking water, dust, carpet cleaners and floor wax.

The EPA also has determined that CASRN 65104-45-2 is designated as “active” on the Toxic Substances Control Act Inventory and is covered by significant new use rules. Therefore, this substance has also been added to the TRI pursuant to the National Defense Authorization Act (NDAA). Additionally, CASRN 203743-03-7 has been identified for addition to the TRI list based on the NDAA’s provision to include certain PFAS upon the NDAA’s enactment. 

As of 2022, the EPA says facilities subject to reporting requirements for these chemicals should start tracking activities involving these PFAS as required by Section 313 of the Emergency Planning and Community Right-to-Know Act. Reporting forms for these PFAS will be due to EPA by July 1, 2023, for 2022 data.

In addition to continuing to add PFAS to the TRI, the EPA says it will soon announce a series of PFAS test orders that will require PFAS manufacturers to provide the agency with toxicity data and information on PFAS.

The United States has more than 2,200 operational anerobic digestion (AD) plants, according to the Washington-based American Biogas Council. However, a number of these plants have failed to perform in line with original predictions, leaving some operators and investors frustrated and disillusioned. There is, though, scope to turn these plants into exemplars of biogas production.

Some of these plants are now approaching their 20th birthday, meaning many major items are now due for servicing or replacement. Also, because of the difficulties involved, many digester tanks are not cleaned as frequently as they should be and any accumulation of inorganic material (such as grit and plastic) will severely limit digestion potential, as well as the operation of internal tank heating or mixing systems.

Fit for purpose

AD involves a complex mixture of biological, chemical and mechanical processes – biogas plants are often compared to the stomachs of cows – and as such it is not surprising that problems can occur. Given that many plants are constructed by several different specialist suppliers (tank suppliers, control system engineers, combined heat and power [CHP] manufacturers, agricultural engineers, etc.), it is a testament to their developers and project managers that many plants work perfectly well.

It is also important to remember that each plant is designed to a specific brief; for example, to process energy crop feedstocks. Over time, diversification and a desire to capitalize on new markets may have resulted in changes to the way AD plants are managed, but if you are now processing food waste in a plant built for cattle slurry and maize, you may well be forcing the equipment to do something it was not designed for.

That said, expansion and modification of an AD plant can be beneficial in many ways, from increasing the range of feedstocks processed to improving digestate management and increasing efficiency. It is important when undertaking such projects that expert advice is sought at all stages and that the integrity of the original plant is not compromised.

With so many potential areas for issues to occur, the first step in improving underperforming plants is often a forensic examination of the complete process, including reverse-engineering individual elements and inspecting all parts for cleanliness, wear and tear and general suitability.

External tank heating

Many older AD plants were built with internal heating elements in the digestion tanks, but there are disadvantages to such an approach. Digestion tanks are an extremely harsh operating environment and often result in premature failure of heating pipes and other equipment.

Also, as already discussed, emptying digestion tanks is a time consuming and expensive process, meaning that equipment such as heating elements is often not serviced as regularly as it might be, or that routine maintenance is not carried out. Also, when internal heating systems do fail, there is no alternative to draining the tank, making repairs or arranging expensive servicing. This is costly in terms of time and labor and lost production capacity.

The solution is to replace internal heating systems with external ones. Using a system based on heat exchangers, like the DTI Series made by Atlanta-based HRS Heat Exchangers (HRS), takes cooler material as it enters the tank (or from the tank) and heats it using a source such as the CHP-engine hot water loop, before passing the warmed product back into the tank.

Not only does this make maintenance of the heating system much easier, but because the heat exchanger can be designed to minimize fouling of the tubes by the digestion material (in the case of the DTI Series, using corrugated tubes), heat transfer is greatly improved and so the heating process is more efficient. Where waste heat from a different part of the process (for example from the CHP engine) is used for digester heating, the energy efficiency is further increased.

Drying the biogas

The biogas produced by AD plants is a mixture of compounds (of which methane is the most important), including water vapor. If water enters a CHP engine it can decrease its efficiency and lead to corrosion, resulting in reduced biogas yields and engine damage. Removing the water also removes a proportion of water-soluble gases such as hydrogen sulfide, ammonia and siloxanes. It can also increase the life of filters and less water in the engine’s fuel means less contamination of lubricating oil.

While some AD plants include condensate traps and “air conditioning”-type chillers, they often fail to remove sufficient water from the biogas mixture. In contrast, the HRS Biogas Dehumidification System (BDS) is specifically designed to remove the maximum amount of water vapor using the minimum amount of additional energy. Rather than heating the biogas to dry it, the BDS uses condensation to remove water from the gas and includes a heat recovery section to further increase overall plant energy efficiency.

By reducing biogas temperatures from around 104 degrees Fahrenheit (40 Celsius) to approximately 41 to 45 degrees Fahrenheit (5 to 7 degrees Celsius), more than 90 percent of the water volume is condensed out of the gas.

A chiller system supplies coolant that is transferred to heat exchangers: biogas flows on the product side of the exchanger, while the coolant flows on the service side. As the biogas cools, the water condenses from the gas, leaving a clean and dry biogas ideal for use in CHP engines.

The heat recovery element means that the cold biogas is used to pre-cool any incoming biogas before entering the CHP. This reduces the load on the final cooling heat exchanger and recovers as much as 20 percent of the energy needed for the process.

Increasing the value of digestate

Digestate represents a valuable income stream for many AD plants, but for its value as a renewable, environmentally friendly fertilizer and soil additive to be realized, digestate must be suitably treated and handled. Above all, digestate must be viewed as a product rather than a waste stream.

If you are processing mixed food waste or other materials, pasteurization may be required. Even where only energy crops and/or manures are used as feedstock, pasteurization is seen by many as an important process to prevent the spread of plant diseases where digestate is used as a fertilizer.

Pasteurization can be an energy intensive process, so it is important that it is performed in the most cost-effective way. The HRS Digestate Pasteurization System (DPS) is commonly based on the three-tank system, so while one tank is being filled, the second tank holds the digestate above 158 degrees Fahrenheit (70 degrees Celsius) and at the same time as the third tank is being emptied. However, two tank systems are also available for smaller units.

In contrast, some traditional systems heat the digestate in a tank using a heating jacket and then dump the heat afterwards. The HRS DPS employs energy recovery and can be two to three times more efficient than some other systems.

Once the digestate has been treated, the DPS system works in reverse, transferring the heat energy from the hot digestate to the water and heating the incoming digestate. By transferring energy from the hotter (pasteurized) digestate to the colder (unpasteurized) digestate, energy consumption is reduced by up to 70 percent, maximizing heat which would have otherwise been wasted.

As well as pasteurization, the nutrient content of digestate can be increased, and the storage and transport requirements reduced, by using a concentration method. In addition, preventing potential ammonia emissions from digestate and AD is increasingly seen as essential to enabling a sustainable biogas industry while also meeting climate change targets. Using the HRS Digestate Concentration System (DCS) can deliver these benefits.

The HRS DCS uses evaporation to reduce the overall quantity of digestate by 60 to 80 percent, reducing associated storage requirements and transport costs. The system includes measures to retain the valuable nutrients in the digestate and reduce ammonia emissions, while the evaporated water can be condensed and reused.

In many cases the captured water is added back to the feedstock as it enters the digester, making the entire process almost self-sufficient in terms of water use and eliminating liquid discharges from the plant. After concentration, the treated digestate can contain up to 20 percent dry solids, making it much easier to transport and handle. As with HRS pasteurizers, as much heat as possible is recaptured and reused in the process.

The right AD system can help boost the energy efficiency of a plant, help cut energy bills, increase the life of equipment and help deal with challenges such as reducing ammonia emissions from digestate. Such upgrades can be applied to systems used in wastewater, food and agricultural AD plants.

The author is international sales and marketing director for Atlanta-based HRS Heat Exchangers.