Putting Waste To Work
American industrial facilities — including food processors — generate and dispose of more than 8 billion tons of solid waste annually, according to the Environmental Protection Agency (EPA). In the food industry, waste includes everything from the obvious — greases, fats, oils, ingredients, byproducts and process wastewater — to the less obvious, such as damaged goods, defective packaging or product overruns. Managing this waste is expensive and labor-intensive. Companies spend money on materials, manpower, cartage and disposal fees, and in many cases, surcharges, fines and penalties. While many food manufacturers have adopted recycling strategies, most of these have been simple end-of-pipe solutions. Ordinary recycling efforts are an important step forward and do help companies reduce their waste and waste-processing costs, but most of these programs come with hefty price tags that are often higher than the processing cost savings.
A concept called beneficial residuals management, on the other hand, is a holistic approach to waste reduction that can help manufacturers derive income or provide cost avoidance by removing materials from their waste streams, and selling or recycling those materials to other manufacturers that use them for entirely unrelated processes. This eliminates the waste, offsets some or all of the management costs, and makes both the waste-generator and residual-user companies greener, and their processes more sustainable, making it a win-win situation.
The Need for Green
With today’s increased environmental regulations and highly educated consumers demanding unprecedented eco-accountability, companies are being forced to rethink their existing waste management and recycling strategies. Further, a recent study by McKinsey & Company shows that 76 percent of executives believe that engaging in sustainability contributes positively to long-term shareholder value. That puts it near the top of the list for many corporate leaders.
Even behemoth Wal-Mart has gotten the message. In 2009, it established a sustainability index, asking each of its 100,000 suppliers worldwide to complete a brief green-practices survey. The first four questions pertain directly to waste reduction.
Tasty Baking Co.’s plant in rural Oxford, Pennsylvania earned kudos from Wal-Mart based, in large part, on its beneficial residuals management program for wastewater. Instead of incinerating, the company now transports the wastewater to local farms for agricultural utilization, so the nutrients in the wastewater are consumed by field crops.
The change reduces the facility’s carbon footprint and saves money in several ways:
- The farms receiving the water are much closer than the incinerator, reducing vehicle use and reducing consumption of fossil fuels.
- The farm crops contribute positively to air quality by making oxygen from carbon dioxide.
- Water reuse lowers dependence on rapidly shrinking water resources and provides a way to replenish the groundwater aquifer.
The beneficial residuals management concept mirrors the organics-recycling pyramid in which preventing waste creation is at the top. The next most desirable outcome is reuse, which is where most beneficial residuals management programs fit. Within the reuse category, beneficial residuals’ hierarchy is to recover and/or create materials that can be used for:
- Humans to eat or use.
- Feeding animals.
- Agricultural benefit.
- Product manufacture.
- Net-positive energy generation.
The goal in all of these stages is to avoid or minimize the processing, handling and energy used to recover or create the residual materials, as these factors affect the cost/benefit ratio. This is a critical step in deciding on an appropriate solution.
For example, a Nestle frozen-food plant in South Carolina struggled with de-watered sludge that had such high grease content with free liquids that it was continuously rejected by landfills. After a full analysis examining the different reuse options for the material, it was determined that composting was the best solution. Now, the composted waste is used as an ingredient by a company that manufactures bagged planting soil sold at home-improvement stores in the southeastern U.S.
High-strength liquid-waste streams that were once a burden, with high disposal costs and, frequently, high sewer surcharges, are now looked upon as a potential fuel for energy production through anaerobic digestion.
Spent coffee grounds, a byproduct of Nestle instant-coffee manufacturing, are utilized in a fireplace log made of only recycled materials and sold as a green consumer product. Cocoa bean shells, a byproduct of chocolate production, are utilized in the mushroom industry as a soil amendment in mushroom production.
Farms often provide the ingredients to create the food products, and can often benefit from the waste from processing that food. Through research with the University of Pennsylvania’s Veterinary School, Kraft found that the mustard seed husks left over from production of its Grey Poupon mustard have beneficial proteins and fats. Kraft now sends those husks to companies that incorporate them into cattle feed. Similarly, White Wave, a soy-milk manufacturer, also utilizes its soybean hulls (okara) for use in animal feeds.
Frozen foods are particularly susceptible to spoilage from improper storage and transport. By handling the packaging and food items separately, it is possible to find effective alternatives to simple landfilling of the entire unit. Misprinted and damaged packaging can be similarly handled.
The beverage industry typically utilizes beneficial residuals management to manage quality assurance/quality control (QA/QC) samples, returns and outdated liquid products. It removes the contents from the packaging, and reuses the liquid for animal feed, agricultural utilization and/or energy production. The glass or plastic packaging can be recycled in a traditional manner.
Beneficial residuals management is helping food manufacturers tackle the decades-long challenge of recycling and managing waste. Through minor process modifications and a fresh outlook, companies can finally find sustainable waste management strategies that can cut the cost of being green.