By Ed Orvidas
Water and energy use decisions in food & beverage plants are often taken in the context of larger corporate-sustainability goals. While everyone, in principle, agrees that sustainability is a good thing, corporate commitment often is needed to affect actual change.
Wastewater management is a big part of food & beverage operations and plant managers want to cut chemicals use, increase brine reclaim, lower blow-down rates and improve grey water reuse. Improving sustainability in these ways also can lead to greater profitability and return on investment.
Food & beverage plants operate as part of a community and must use local water and energy supplies efficiently and responsibly. Consumers today more often scrutinize how products are made. Companies having measurable, attainable sustainability goals may be one step ahead of the competition.
Thus, eco-friendly initiatives evolve from mere “feel-good” programs into something that can quantifiably reduce environmental impact even as it mitigates company costs. And many successful food & beverage makers are already learning that this is the case.
First step in establishing an effective water-saving program is to gain understanding of where water is used; how much of what water streams flow through the plant; and what the quality of flow is.
Next, emphasize water usage as a plant metric, alongside production data. These metrics can be formulated into annual goals and even be a basis for plant-manager incentive programs.
If it currently takes four gallons of water per every gallon of beverage produced, an annual goal might be to reduce this to 3.75 gallons of water per every gallon of beverage produced.
Finally, investigate industrial-water treatment solutions that deliver quality water, operations efficiency and savings. Technology-solution advances make attainment of sustainability goals a plausible reality.
Reverse osmosis equals energy and cost savings
Adding a reverse-osmosis (RO) unit to an existing boiler-treatment system ensures water going to the boiler is highly purified. This allows operations at high cycles of concentration and results in less blow-down water going to the drain — e.g., based on the addition of fresh make-up water so as to reduce solids that are in the boiler. Lower blow-down rates mean less water and energy or heat lost.
Dependent on operating conditions, using reverse osmosis to reduce blow-down frequency saves energy. In one known example, a global beverage maker reduced boiler blow-down from 15% to 2% using a reverse-osmosis unit. Savings amounted to an average $61,000 per year.
Brine-reclaim saves salt
Brine-reclaim technology not only “reclaims” system efficiency. It also reduces the water and salt used in a typical softener regeneration cycle. With brine reclaim, a portion of reusable brine is returned to the brine tank during softener regeneration. This reduces the salt needed to remove hardness and the water used per regeneration cycle.
During reclaim, how much brine is directed to the tank is directly proportional to how much salt is saved. The savings can be significant. It’s not uncommon for companies that have implemented softener brine reclaim to achieve an immediate 20% in salt savings. For those that have been spending $15,000 or more in salt per year, a return on investment can be expected within one year.
Reclaim a waste stream
For food & beverage makers with a reverse-osmosis unit or nano-filter in place, a reclaim reverse-osmosis unit added to the reverse-osmosis or nano-filter waste stream can reduce wastewater amounts by up to 60%.
For example, because of the high quality of its nanofiltration system reject water, one large fruit-juice manufacturer is known to have been able to reclaim nearly 30-million gallons of water per year by adding a reverse osmosis unit to the waste stream, saving $250,000 annually on water and wastewater rates.
Mixed oxidants are a powerful disinfectant
An inherently green technology, mixed oxidants can be created at a plant site using salt, electric power and conversion cells. The solution is used in applications that require oxidizing biocides, such as sodium hypochlorite. Mixed oxidants eliminate the need for hazardous-chemicals storage and are a more powerful disinfectant than conventional chlorine.
In food & beverage industries, mixed oxidants disinfect incoming plant water by replacing calcium and sodium hypochlorite and gaseous chlorine. They can also be applied to clean-in-place and bottle-washing operations.
Mixed oxidants safely and effectively flush out beverage lines, for example, to ensure that lingering flavor notes are eliminated between flavor changes. With mixed oxidants this can be done 40% faster than with conventional hot clean-in-place. And it is accomplished under cold water conditions — reducing down time and saving energy.
High-efficiency ultraviolet light
Today’s ultraviolet (UV) light systems make use of materials that increase the efficiency of the reflected UV light, improving contact in the water stream. These next-generation systems deliver the same flow and UV dose rate as yesterday’s solutions, but in a smaller footprint. They reduce the number of bulbs and energy required compared with traditional UV systems. In many cases, companies can realize a short, two-year return on investment based on energy and bulb replacement savings.
Grey rinse water reclaim
In a typical plant, many opportunities exist to reclaim “grey” rinse water using ultrafiltration methods to remove dirt or suspended particles. Ultra-filtered water can then be further purified using conventional reverse-osmosis treatment methods to enhance the purity of final reclaimed water, which can then be collected and redirected for possible reuse. Grey water reclamation depends greatly on having an understanding of a plant’s water balance, so that certain waste streams can be isolated, evaluated and then reclaimed.
It’s clear that industrial water-treatment solutions can dramatically impact achievement of sustainability goals and metrics. These technology solutions have already been demonstrated and proven in many food & beverage plants and have delivered measurable return on investment. Savings are achieved through reduced water and energy consumption, as well as lower operational costs, while maintaining or improving product quality, safety and compliance.
In the end, what’s critical is to take a holistic solutions-based approach to creating a water savings program specifically targeted to a company’s unique goals and metrics, right from the start.
Ed Orvidas is Director, industrial strategic accounts, Culligan Matrix Solutions, the commercial and industrial division of Culligan International Company, a global innovator of advanced water softening and filtration solutions for more than 75 years. With its single-source, comprehensive water treatment technology platform for virtually any industry and application, Culligan Matrix Solutions addresses the needs of businesses for end-to-end water treatment systems that are faster, more efficient and cost-effective than ever.