A Five-step Approach for Improving Your Plant’s Waste Stream Processing

Aerospace manufacturers are at a crossroads.

With the promise of advanced air mobility technologies such as electric-powered air taxis and cargo shuttles on the horizon, significant growth is projected for the aerospace industry.

However, for an industry characterized by such futuristic technological advancements, many aerospace manufacturers are slow to elevate their waste management and recovery processes. Too often, these processes are considered secondary to production. That approach will gradually cut into an organization’s bottom line, as environmental compliance becomes more tightly regulated and the shift to the circular economy accelerates.

Aerospace manufacturing facilities have the potential to produce hundreds of waste streams —it’s enough to keep a plant’s entire environment, health, and safety department awake at night. Lacking the adequate processes to cost-effectively manage waste streams and environmental compliance puts aerospace manufacturing companies at risk for millions of dollars in penalties and fines.

Unfortunately, the battle for capital expenditure continues to be the biggest hurdle facing environmental compliance managers and providers of waste reduction solutions. With that in mind, outlined below are five suggestions for getting stakeholders on board and implementing waste stream processing advancements in aerospace manufacturing plants.

1. Educate stakeholders about liability risks and begin to shift their perception about environmental compliance from “burdensome expenses” to “lower raw materials costs” and “increased metal scrap value.”

Environmental responsibility and sustainability are equally important to an aerospace manufacturer’s bottom line. This is in part due to the steep financial penalties associated with failing to comply with local, state, and federal waste regulations. However, establishing processes that support sustainability also lowers costs, and in many cases, even generates revenue.

Hazardous waste is one of the mostly strictly enforced regulations across the country — be sure stakeholders are aware of the scope of metal scrap and fluid disposal liabilities. Storing spent cutting fluids on-site is an environmental risk in and of itself. But chips and turnings saturated with hazardous fluids can also become a liability for the manufacturer if a lawsuit is filed against a recycler that disposes of hazardous materials improperly.

The more used coolant or machine oil a manufacturer sends to the recycler, the greater the chance of being implicated if disposal problems arise. By proactively addressing fluid and chip remediation, manufacturers can help shield themselves from liability by proving good intent.

2. Establish an environmental compliance program.

At minimum, aerospace manufacturers should use ISO 14001 as a baseline to develop an environmental compliance program. Although ISO 14001 does not state specific requirements for environmental performance, it establishes criteria that companies can follow to develop an effective environmental management system.

Third-party accredited certification is available for the standard, though it is not a requirement. Plants will benefit from the guidance the standard provides without completing the certification process. ISO 14001 provides assurances to company management, employees, regulators, customers, and the general public that the operation’s environmental impact is being measured and improved. Meeting the criteria of the standard will also reduce waste management costs and lower consumption of energy and materials.

3. Identify aspects of operations that will mitigate risks or yield material savings.

A company’s machining operation is a smart place to begin an environmental, health and safety assessment. Equipment such as screw machines, gantry mills, CNC lathes, and drills can generate large quantities of hazardous scrap metal and coolant wastes. Reclaiming and recycling these materials not only improves workplace safety and reduces environmental impact, but it can also yield significant bottom-line benefits.

Grinding/honing operations, cleaning processes, and even recycling practices related to wash and mop water, should also be part of the assessment. As water becomes an increasingly precious commodity, implementing strategies for recycling and reclaiming process water and reducing wastewater volumes will contribute to lower water and disposal costs.

4. Enlist assistance from a total solutions provider of waste stream processing equipment to identify back-end investments that will benefit your operation the most.

Although acquiring off-the-shelf processing equipment may be convenient, in the long run it may not provide the best value over its service life. Partnering with a total solutions provider is essential to optimizing return on investment and lowering total cost of ownership.

Aerospace companies weighing waste stream processing equipment options should seek out a supplier who performs laboratory testing. Testing performed prior to purchase provides many benefits. Regarding metal scrap processing and fluid recycling systems, testing can confirm:

• How much fluid will the system be able to recover?
• How much will it lower new fluid purchases?
• What is the moisture content before and after processing, and how much will that increase the scrap value?
  

Industrial water treatment solutions are as unique as each application’s water chemistry. Therefore, suppliers that incorporate a laboratory analysis into their specification process are more likely to deliver a solution optimized for the application, reduce equipment lead times, and deliver proof of capabilities prior to installation. A higher level of equipment specification will also afford higher rates of equipment reliability.

5. Enhance waste stream processing by leveraging the latest metal scrap processing, fluid recycling, and water processing technologies available.
   

• Metal Scrap Modification

Decreasing the volume of metal scrap is essential to effectively managing solid waste material in aerospace applications. Increasingly, aerospace manufacturers are updating their processing system to reduce the metal scrap at the front end of the process. Utilizing a crusher or shredder unit at the discharge of the CNC conveyor adds value in several ways:

• The frequency of handling and transferring hoppers loaded with material is reduced.
• The work zone near the machine becomes safer.
• Equipment damage caused by material and belt jamming is prevented.
• Because the volume of the metal scrap is decreased, more material can be loaded in containers. This allows plants to get higher value for their scrap, because the recycler is hauling away a truly full 40,000-lb. container, not a container full of voids.

Processing the material in a crusher or shredder also transforms the metal scrap into shovel-grade material that is suitable for further processing in a wringer. A modern centrifuge or chip wringer utilizes up to 700g of centrifugal force to remove upwards of 98% of the free liquids from the material. Dry chips, which are more valuable to a scrap dealer, can then be sent pneumatically or by gravity to lugger boxes, semi-trucks, or a storage silo.

Aerospace manufacturers are also leveraging briquetter systems to meet environmental compliance requirements and literally squeeze more value out of waste material. Briquetters incorporating dual compression technology use high compressive force from two opposing cylinders to form highly dense, dry pucks. The pucks have an average solid density of 85%-to-90% and are up to 99% dry. As a result, they are more valuable to scrap dealers, commanding up to 25% more value compared to loose metal scrap. Briquetters also reclaim valuable waste fluids from the material that can be recycled and reused. 

• Cutting Fluid Recycling

After cutting fluids have been reclaimed through wringing or compression, a cutting fluid recycling or filtration system will enable aerospace manufacturing plants to reuse the fluids. This can substantially reduce both new fluid purchases and the need to store hazardous fluids on-site until they can be disposed of. Haul-away costs also drop. Finally, centralized systems that incorporate coolant management capabilities help kill bacteria and control viruses, yeast, and molds that contribute to health problems such as dermatitis.

Water Treatment

Water used in aerospace manufacturing processes can be recycled and reused if treated properly. Treating process water onsite and reusing it within the operation establishes sustainable practices that will lower operating costs and protect the environment. Wastewater, which faces strict disposal regulations and is expensive to dispose of, can also be treated onsite.

Industrial water and wastewater treatment is not one-size-fits-all. Water treatment systems need to be custom designed for the unique characteristics of your plant’s water and wastewater. However, aerospace manufacturers that position their operation to meet Zero Liquid Discharge goals will realize significantly lower water and disposal costs.

Aerospace manufacturers can no longer afford to view investments in waste stream processing as merely expenses and continue to defer them in favor of production enhancements. As the industry continues to move toward achieving sustainability mandates, while simultaneously transforming aviation technologies, waste stream management will play a larger and larger role in profitably meeting those objectives. Begin incorporating environmental compliance initiatives into a continuous improvement plan today to ensure consistent waste stream processing improvements that will benefit the operation long term.

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