As we look at those changes over the last 25 years, several trends emerge in the increasing use of technology in how we design, construct, document, and operate these facilities.
By Evan Williams and Chris Hawn
The last 25 years have seen significant developments in many key areas of performance for Material Recovery Facilities (MRFs). These changes can be grouped into several categories, but the consistent through lines converge over increased use of technology, a focus on safety, and an eye toward future flexibility. Let’s take some time to look back over the shifts in MRFs over the last 25 years and why they occurred.
Design the System for the Material
This may be a bit of an oversimplification, but one trend has been the increasing focus and ability to design the recovery system for the specific needs of the end user and the material that will be sorted. This relies on several factors: the ability of the end user to provide accurate and stable waste characterization, as well as a good market survey of the local area to determine the needs and market for the target commodities. In addition, the increasing ability of MRF system designers to dial in systems to pursue more desirable commodities and deliver an end-product that aligns with the purity needs of the local market can yield long-term value for system operators. For example, some areas have capacity and need for plastics sorted by type with a high level of purity and will pay a premium for this. In those areas, investing in additional optical sorters and QC stations would likely make sense, but in other places, there is no local market or price premium for this, making it difficult to justify. There are other strategies that can be deployed to align the MRF’s capability with the local market; however, the overall strategy is to align the equipment and operational resources with the local market’s needs.
Increased Incorporation of Technology
You cannot walk through a new MRF without seeing the increased use and integration of technology to improve all aspects of MRF operations. Over the last 25 years, new technologies have enabled operators to monitor their system throughput in real time. MRF designs have evolved in areas such as automated QC, mechanical pre-sort, and AI implementation across several products, including sorting robots, optical sorters, camera vision systems, business intelligence platforms, and more. The innovation of new sorting technologies represents a dramatic change, but we can also witness the increased amount of automation. At the beginning of the 2000s, one or two optical sorters were considered a fairly automated system. Nowadays, you can frequently witness 15 to 20 plus optical sorters, and that number is still growing. In addition, emerging technologies allow operators to monitor their yellow iron and implement preventive maintenance, and even component repair, before failures occur. Another feature of the increased use of technology has been the emergence of the ability for operators to modify their system sorting preferences in real time to their needs. Other technologies that are being developed allow for more accurate logging of the material in real time for tracking the composition. This can be helpful to understand the incoming material stream and whether increased public outreach and education are needed to address issues.
3D Modeling, BIM, and 3D Scanning
Twenty-five years ago, 3D modeling was in its infancy, while Building Information Modeling (BIM) and 3D Scanning existed but were not market ready. Since that time, the capabilities, market adoption, and efficiency of these three technologies have converged, greatly improving the ability of equipment system designers, balance of plant designers, and facility operators to better understand. For an existing facility, a 3D scan can produce a workable model in a workable format (e.g., Revit) for the building team, as well as a point cloud for the project team to reference for specific conflict confirmation work. The equipment system designers have long adopted 3D modeling for their system design, and over time, the rest of the Architecture, Engineering, Construction (AEC) market has adopted it to allow the entire project delivery team to speak the same language and work in the same 3D environment. This yields several benefits:
- It minimizes equipment/building conflicts through the use of the same shared 3D environment. Since the equipment can be overlaid on the building drawings, areas of conflict can be identified and addressed.
- The 3D scan of existing buildings can identify issues that may not be noted on a simple hand-measured survey. Sometimes, out-of-level floor slabs, inconsistent steel elevations, and irregular building elements can be tough to document accurately without a 3D scan. This can identify building issues that need to be addressed or avoid conflicts.
- The use of 3D design in project development and 3D scanning of existing elements, as well as the use of BIM to create an accurate as-built for future modifications. If the operator has a good as-built, it makes evaluating and developing future modifications or expansions much easier, shortening the timeline to deploy future improvements.
The trend in system and balance-of-plant design and engineering has been increasingly toward more 3D design and the incorporation of BIM. Where appropriate, 3D scans of existing buildings and system elements can further improve the accuracy of new work and decrease the risk for errors and disconnects between the various project partners.
MRF Design Strategies and Sorting Technology
We experienced a boom in MRF throughput in the early 2000s. The capacity MRF operators planned for was dramatically increased, which impacted the design strategies of the system. This is when systems were engineered for performance, efficiency, and maintenance. Nowadays, in the current political context, MRF designers must take into consideration recycling policies and regulations that are shifting, such as EPR and others. Automation and operational flexibility are the keys to adapting to changing recycling policies and regulations. Another area that has dramatically evolved is the control room. Decades ago, the Scada was installed in an isolated office somewhere and was underused. Today, data is gold. There are entire rooms dedicated to Scada, and control rooms.
Furthermore, those control rooms now have multiple screens allowing them to monitor daily operations, detect long-term trends, and monitor failing equipment, CCTV cameras monitoring the entire facility, Forward Looking Infrared (FLIR) cameras to detect signs of heat, and more. An emerging design strategy that requires collaboration between equipment manufacturers and construction companies is the maintenance-friendly MRF design. For example, this would be planned during the design phase for overhead cranes in strategic areas. This can also include a smaller item, such as a plan for a door to the baling area, which could provide more space for bale storage.
Safety
There are several areas where MRF design and operations are changing to address life/safety risks. The well-documented fire challenges that lithium-ion batteries present to facilities have led to several risk-minimization strategies, including:
- Use of automated and manned fire identification and extinguishing systems
- Implementation of AI-driven battery identification cameras in the system in-feeds
- Placement of deluge sprinkler heads over sorted material bunkers
- Use of ESFR or similar high-density sprinkler systems over bale storage areas
- Use of High Pile Storage layout and building access in line with IBC chapter 32; this is an emerging area of the code, as the classification of mixed plastics and how they are stored has been changing in more recent versions of the code
Other newer safety-related approaches include automating tasks related to repetitive stress injuries. For example, how automated collection trucks reduced injuries and the use of automated in-feeds with roll screens, trommels, and sorting robots to reduce the head count of staff engaging in tasks that result in repetitive stress injuries. Another safety approach can incorporate employee location tracking with yellow iron to notify equipment operators when staff are walking nearby.
Building for Flexibility
A noteworthy facility design approach over the last 25 years has been the need to design for flexibility and adaptability. Since facilities have a lifespan of 30 to 50 years, while the systems within them have a useful life of less than 20, it is crucial that the balance of plant (building and site) be designed with an eye toward future modifications. For the site, this often manifests in looking at the facility plan to identify likely areas where the building may need to be expanded over time and provide undeveloped site area(s) for this. This can typically be done by providing area(s) to expand the tipping floor, increasing the bale storage area, adding an additional scale, etc. Available property does not always allow for this, but it is good practice if possible.
An additional site consideration is designing site utilities to ensure that they do not conflict with potential future expansions. There is typically little to no cost in this effort, but it avoids future expenses and costly rework. In the building’s general design, interior columns should be minimized, if possible. In addition, the roof structure should be designed with additional collateral loading to allow for additional roof-mounted equipment, added sprinkler lines, solar, etc. We typically add 5 to 10psf to the baseline loading values if those future loads are a possibility, as the initial cost is low compared to the difficulty of increasing load capacity later. In addition, the building should be designed with expandable walls in areas where future expansions are likely. Again, this is a minimal upfront cost that minimizes future reworking and expenses.
Dramatic Improvements
Walking through a MRF 25 years ago versus today may in many ways seem very familiar—they have the same general elements in tipping areas, sorting systems, and bales—but how the system actually sorts the material, the end products it produces, the product purity, and the manpower needed to get that result all illustrate dramatic improvements over that timeframe. As we look at those changes over the last 25 years, several trends emerge in the increasing use of technology in how we design, construct, document, and operate these facilities. The trend is to use technology to better document the facility, both for initial construction and to ease future modifications. Another trend is to use technology to improve the sorting operations to increase sort quality and safety. Technology is also used to improve system and yellow iron maintenance. It is even being used to minimize fire risks. Given the changes and improvements in MRFs over the last 25 years, it will be exciting to see what the future holds. | WA
Evan Williams is Design Project Manager for Cambridge Companies. Evan, a strategic visionary, focuses on balance-of-plant design and development, operations integration, future planning, safety accommodations, and site design for waste and recycling facilities. For the last 18 years, he has worked closely with clients to help develop the design parameters of each unique facility, incorporate lessons learned from previous projects, and actively monitors emerging industry trends for facility integration. Cambridge Companies, Inc., a design-build firm specializing in the environmental and waste industries, has completed more than 250 projects. During this time, Cambridge has successfully completed a wide range of solid waste design-build projects, including material recycling centers/MRFs, RNG facilities, transfer stations, truck and heavy equipment maintenance shops, landfill support facilities, and more. The Cambridge team continually monitors industry trends and ever-evolving needs to provide superior, relevant solutions when planning and building new facilities, ultimately benefiting clients seeking design-build solutions. Evan can be reached at [email protected]. For more information, visit .
Chris Hawn is CEO of Machinex. He is a seasoned leader in the waste and recycling industry, currently serving as the CEO of Machinex Technologies. Since assuming this role in 2017, Chris has been instrumental in driving the company’s growth and innovation as a leading turnkey MRF manufacturer in North America. Chris’ industry contributions were recognized with the NWRA Suppliers Distinguished Service Award in 2021. Machinex is an industry leader in engineering, manufacturing, and installing Material Recovery Facilities all around the world. As an expert in sorting technologies, Machinex provides turnkey systems, along with custom-built and flexible solutions, to help ensure customers remain ahead of the competition. They also offer a full range of high-quality recycling equipment manufactured in-house, giving customers a complete system integration. Chris can be reached at (336) 899-8514, e-mail [email protected] or visit