Water reuse in the food and beverage industry

Home 9 Blog 9 Wastewater reuse in the food and beverage industry

Food and beverage manufacturing takes a lot of water. No mystery there, since water has myriad roles in food processing, where it is used as an ingredient, as well as for cooking, processing, transport, cleaning, cooling, or a host of other applications. But in a time of looming water scarcity, food and beverage manufacturers are increasingly adopting water reuse applications as part of an effort to operate more efficiently.

What is water reuse?

Water reuse is the collection and treatment of wastewater, process water, graywater or other streams for use in additional applications, the chief goal of which is to reduce overall use and consumption of water. The adoption of water reuse strategies is on the rise across many major industries, including all food and beverage market segments. Used as part of a water optimization strategy, water reuse can yield many benefits, ranging from cost savings to insuring long-term operational viability.

Water reuse applications in the food and beverage industry

Food and beverage manufacturers make up a large industry where water serves a diverse array of functions. For that reason, food and beverage water reuse applications are as unique as the facility that adopts them. To give a sense of the range of potential reuse applications, we’ve compiled some examples by food and beverage market segment:

Beverage & brewing

A common reuse strategy for bottling plants is recapturing final rinse streams for use in the pre-rinse or pre-wash phase of a subsequent bottle washing cycle. This may be done without treatment since the detergents or sanitizing agents remaining in the final rinse water will not interfere with earlier pre-washing phases. Other reuse applications in the beverage industry include reusing process wastewater for cleaning of vehicles and facilities, and as boiler feed water.

Dairy

Common reuse applications in the dairy industry include capturing pasteurizer overflow water or waste streams from cooling, rinsing, or other activities for reuse in landscape irrigation, as utility water, or for cleaning floors and vehicles. Another opportunity for water reuse is the collection of condensate from activities such as milk homogenization, cheese production, and milk powder production. Due to the nature of the evaporation process, the collected condensate is safe for use as process water with little to no treatment.

Fruit & vegetable processing

Water is used extensively in fruit and vegetable processing for activities like washing, grading, peeling, and trimming. In some cases, these process streams may be recovered and recirculated for repeated use in the same application, sometimes with no treatment. Alternatively, if the cost or complexity of treatment does not support direct reuse, produce processing wastewater is sometimes reused in non-food-contact applications, such as for irrigation, facility cleaning, and cooling.

Meat, poultry & seafood

Water uses within the meat processing industry include chilling, scalding, can retort processing, carcass washing, cleaning, and transporting wastes. Wastewater treatment and reuse can be difficult due to sanitation concerns, however, implementing procedures to keep waste streams separate can make reuse more economical, such as by screening out solids, or using dry conveyors rather than wet for transporting wastes. Reuse applications can include capturing water from chilling and scalding and using it in flumes.

Sugar & confectionary

One of the key opportunities for water reuse in sugarcane and sugar beet refineries is condensate recovery. Collected condensate may be treated and reused in various applications, including grinding processes, as boiler feedwater, facility sanitation, irrigation, and for use in cooling towers.

Benefits of water reuse for food and beverage applications

Water reuse applications offer several advantages for food and beverage processing facilities. First, water reuse strategies can help food and beverage manufacturers cut costs by reducing the amount of water a facility needs to draw from local water sources. Water reuse can also reduce the volume of wastewater generated, which can in turn help facilities reduce wastewater discharge costs.

Additionally, treating water for reuse often provides opportunities for recovery of valuable resources along with water. Compared to other industries, wastewater streams from food and beverage processing often have high loads of organics, as well as fats, oils, and greases (FOG). In the process of treating these streams for reuse, facilities are sometimes able to reclaim nutrient-rich byproducts that can be sold for use as agricultural fertilizers. Similarly, biodigesters, MFCs, and other biological treatment processes can be used to convert organic wastes into energy, such as by producing fuels like biogas, or by generating electricity that can be used to power internal operations or sold back to the grid.

Finally, water reuse can help facilities meet corporate sustainability goals. This can help appeal to a growing share of consumers who prioritize sustainability in their buying decisions. Water reuse can also be an important part of an ESG strategy because it helps food and beverage manufacturers to operate more efficiently, which will only become more essential as the industry copes with future threats of scarcity and rising costs for water and other resources.

Future directions for food and beverage water reuse

For the most part, water reuse applications in the food and beverage industry consist of downcycling, where wastewater streams are captured for use in applications with less exacting standards. This can include recycling process streams for use in heating, cooling, cleaning and irrigation applications, for example. Whether due to challenges of technical impracticality, cost, or negative perceptions of wastewater, wastewater is rarely used in applications where the stream comes in direct contact with food or beverage products. Unfortunately, this leaves a lot of potential water reuse opportunities on the table.

There are, however, some indications that this may change in the future. As treatment technologies have evolved, it has become technically and economically feasible to restore nearly any process or wastewater stream to a level of purity that meets or even exceeds the quality of tap water. Some companies are even starting to experiment with novel reuse processes, such as beer made with water reclaimed from treated sewage. It may take some time yet, but it is likely that concerns around water scarcity will eventually motivate consumers, regulators, and food and beverage manufacturers to get more comfortable with the idea of using recycled water in food contact applications.

Treating water for food and beverage reuse applications

For health, safety, and quality reasons, any water that comes in direct contact with food or beverage products will generally need to meet or exceed drinking water quality standards. This includes not just water that comes in direct contact with the products themselves, but also water used to clean any surfaces that contact food and beverage products. Water that is reused for non-food-contact applications—like cooling towers or washing out trucks—can be of lesser quality, but still must be suitable for the task at hand. For this reason, treatment systems for reuse applications vary substantially from application to the next.

Regardless of whether a stream is destined for reuse or discharge, it is often necessary to combine multiple treatment technologies into what is known as a treatment train. Combining multiple technologies allows for the most efficient treatment of streams with a complex variety of contaminants, or those with high loads of contaminants. In addition to conventional wastewater treatment systems, water treatment technologies commonly used to treat streams for food and beverage reuse applications include:

Reverse osmosis (RO) and nanofiltration (NF). RO/NF are membrane separation technologies that offer near-complete removal of contaminants, including pathogens, heavy metals, chemicals, and salts, producing a high-quality stream that is suitable for nearly any reuse application. Additionally, RO and other membrane technologies produce a concentrated reject stream that can be useful for recapturing byproducts or minimizing liquid wastes.
Ultrafiltration (UF) and microfiltration (MF). MF/UF are energy-efficient solutions for removal of bacteria and suspended solids. They produce streams of moderately high quality that are suitable for direct reuse in some downcycled applications. Additionally, MF/UF are useful for pretreatment ahead of more sensitive downstream technologies, such as IX or RO/NF.
Membrane bioreactors (MBRs). MBRs offer a lot of promise for food and beverage reuse applications, since they provide an efficient and compact means of treating wastewater with high concentrations of organics. The effluent is also of high enough quality for some reuse applications.
Ion exchange (IX). IX removes certain dissolved contaminants and replaces them with other substances, allowing facilities to achieve targeted removal of impurities from liquid streams without wasting resources on removing innocuous constituents. IX resin technologies can also be useful for recovering valuable materials other than water, such as recovery of lactose in dairy processing, or recovery of sucrose from molasses in beet sugar refineries, among many other applications.
Disinfection deactivates any pathogens present in a stream, and may be necessary for some reuse applications in order to ensure product quality and safety. Common disinfection methods include chemical addition of chlorine, exposure to ultraviolet (UV) light, or injection of ozone gas into the liquid stream.

An effective water treatment train may combine any of these or other technologies. The best treatment solutions for reuse applications will consider several factors, including the quantity, quality, and constituents of the process wastewater stream to be treated, and the acceptable parameters of the treated water, while also balancing system size, capital costs, and operating costs with the needs of the owner.

How can SAMCO help?

SAMCO has over 40 years of experience designing and manufacturing custom water treatment systems that optimize industrial water use. We have helped industrial clients meet important goals, like conserving water, cutting waste, and reclaiming valuable resources—including those in the food and beverage industries. If you have questions about what water management solutions may be right for your facility, contact us to set up a consultation with an engineer. Our experts will help you understand the process for developing water optimization solutions for your facility, and determining a realistic budget for your water reuse project.

You can also click on over to our blog to learn more about water management and wastewater treatment issues impacting the food and beverage industry, and other sectors as well. Relevant articles include: