Fecha de publicación: 05/12/2024 Fuente: Food Processing As environmental concerns escalate and regulations become stricter, the importance of sustainability and efficient resource management in the manufacturing sector has never been greater. In response to these pressures, one Spanish ice cream producer has embraced an innovative solution to tackle its challenges head-on.

The manufacturer, known for producing a wide variety of ice cream products for various third-party brands and retailers, recently encountered significant obstacles in managing its wastewater treatment process. Striving to maintain a balance between effective treatment and environmental sustainability was essential to its operations.

Ice cream manufacturers often struggle with managing wastewater effectively, especially when using traditional aluminium-based coagulants. These treatments, although occasionally effective, can be markedly unstable and highly sensitive to pH changes. The process also demands substantial amounts of caustic soda for pH homogenisation, which increases the discharge conductivity, frequently surpassing legal limits. Furthermore, these aluminium treatments can lead to unwanted effects in downstream biological treatment processes, complicating the overall wastewater management. For this Spanish ice cream manufacturer, these challenges were particularly pronounced during the dissolved air flotation (DAF) step of its wastewater treatment line.

An organic solution

Recognising the need for a more stable and environmentally friendly solution, the manufacturer engaged Veolia Water Technologies to recommend a solution. Veolia’s Hydrex team in Iberia, Spain, proposed replacing the metal-based chemicals with a Hydrex plant-based coagulant. Traditional metal-based coagulants, while effective at removing suspended solids and contaminants, have several drawbacks, including significant changes to the pH of water, high sludge production, and increasing regulatory restrictions on their use.

The Veolia team conducted extensive trials and jar tests to demonstrate the efficacy of the plant-based coagulant. Impressed by the results, the manufacturer signed a contract for the supply of 100 tons per year of the Hydrex plant-based coagulant.

Derived from renewable sources, Hydrex plant-based coagulants are designed to provide a sustainable and cost-effective alternative. These products are formulated to mitigate the drawbacks of inorganic chemicals, particularly in the oily effluent generated by the food and beverage (F&B) industry.

The results

Chemical dosage reduction: The dosage of poly aluminium chloride (PAC) was reduced from 1000 to 300 ppm, while the dosage of caustic soda was reduced from 1000 to 300 ppm (v/v). This led to a 40% reduction in chemical costs for the manufacturer.

Improved stability: The plant-based coagulant provided a more stable treatment process, less sensitive to pH variations.

Sludge production reduction: The DAF system produced less oily sludge, easing the burden on downstream treatment processes.

Enhanced performance: The treatment achieved similar performance to PAC, with a 50% reduction in chemical oxygen demand (COD) and an 85–95% reduction in total suspended solids (TSS).

Conductivity improvement: The conductivity of the discharge was reduced from 6000–7000 µS to 4500 µS, a critical improvement for meeting legal discharge limits.

A spokesperson for Veolia Water Technologies Ibérica said, “With our Hydrex plant-based solutions, Veolia has resolved the ice cream producer’s DAF performance issues and reduced their total costs. As a result, the customer will save approximately €80,000 per year if all circumstances remain consistent over time.”

The success of this project underscores the broader industry trend towards sustainable practices in the food and beverage sector. Wastewater treatment plants in food and beverage facilities often face challenges such as load shocks, temperature changes and production increases. Conventional activated sludge treatment systems are often inadequate for handling the large variations in Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), and nutrients caused by ingredients like sugars, proteins and starches.

Removing COD, BOD and nutrients from wastewater is crucial for protecting aquatic life and the environment. The adoption of advanced wastewater treatment technologies can help companies in the food and beverage industry meet these challenges.

By adopting Veolia’s plant-based coagulants, the Spanish ice cream manufacturer not only improved its wastewater treatment process but also took significant steps towards environmental sustainability and cost savings.

Image credit: iStock.com/sameer chogale