Be prepared for the cold weather

Tips and Tricks for Winterizing Your Biological System

Increasing Your Target MLSS: One of the most common operational adjustments during winter is increasing the concentration of mixed liquor suspended solids (MLSS) by 25-50%. Since bacteria work at slower rates during cold weather and hydraulic retention times remain unchanged, a higher biomass concentration is needed to maintain treatment performance. However, this change must be planned before cold weather sets in, as it can be more difficult to raise MLSS concentrations once temperatures drop. ProBlend CT should be included in your winterization plans to make your biomass more temperature resilient. The proactive addition of psychrophiles is typically more optimal and provides cost-savings over having to dose higher amounts after temperatures have already declined. 

Keep an Eye under the Microscope: Low temperatures can also exacerbate settling and foaming issues caused by filamentous bacteria, such as Microthrix parvicella. In cold conditions, fats, oils, and greases (FOG) become less soluble and biodegradable, making them more prone to accumulation in the system. M. parvicella, however, thrives on these conditions, leading to potential foaming and settling problems. Bioaugmentation with ProBlend FOG-MN and ProBlend CT can help establish a cold tolerant and FOG loving population to help outcompete Microthrix before they can get fully established. In some cases, a lipase enzyme like Lysa L can be utilized to solubilize the FOG before it can congeal and create scum layers that help select for Microthrix.

Stabilize Nitrification Rates: One of the most notable effects of cold temperatures on treatment systems is the potential loss of nitrification. Nitrifying bacteria are particularly sensitive to temperature changes and are often the first to show signs of stress when conditions change. While some nitrifiers can tolerate cold temperatures, nitrification typically becomes compromised below 10°C. Augmenting with ProBlend N500 can help boost nitrification rates and keep a happy and healthy nitrifier population.

Reconsider Aeration Demands:  Colder water holds more oxygen than warmer water. For this reason, reconsider your aeration demand as you may be wasting significant energy providing excess DO. Better yet, upgrade to automatic dissolved oxygen (DO) setpoint control.

Review your Macro and Micronutrients: Some wastewater treatment plants, particularly those with industrial sources, often need to adjust nutrient levels during the winter months to account for both an increase in biomass and the additional energy required for cell maintenance. For example, when bacteria produce lipases for FOG breakdown, they require more trace minerals to do so a lower temperatures (namely zinc, magnesium and copper). The addition of iron, zinc and manganese have also shown stimulatory effects in low temperature applications. Thes trace minerals can be supplemented easily using a liquid micronutrient blend such as ProBlend LMN.

Ensure Piping and Tubing is Insulated and/or Heat Traced: Inspect all outdoor and exposed piping and tubing lines for risk of freezing. Adding insulation and heat tape is a simple and cost-effective way to reduce the risk of disastrous failures. Containers like totes and drums for critical chemicals should also be reviewed for the addition of heaters or electric blankets.

Contact our Water Treatment team about our winter solutions

By combining physical system adjustments with strategic bioaugmentation, operators can better prepare their wastewater treatment systems for the operational challenges of winter, ensuring continued performance even in the coldest months.

If you have questions, would like more information, or are ready to request a quote, contact our team by completing the form to the right.