What Causes High BOD in Wastewater?

A quick answer is petroleum or chemical based waste has a very high Oxygen demand. In order to help you determine what is causing your high BOD levels one must understand what BOD is.

Understanding BOD

Factors Influencing High BOD Levels

Several factors contribute to elevated BOD levels in wastewater, each playing a role in the degradation of water quality:

Organic Matter Input

Organic matter originates from various sources, including human waste, food, and vegetation. When excessive organic matter enters water bodies through sewage, stormwater runoff, or agricultural discharges, microbial decomposition ramps up. This heightened microbial activity results in higher BOD levels as microorganisms consume oxygen while breaking down organic compounds.

Lack of Adequate Treatment

Inadequate wastewater treatment processes can be a significant factor in driving up BOD levels. When wastewater is not properly treated to remove organic matter, it gets released into water bodies with high BOD concentrations. This, in turn, leads to oxygen depletion in the receiving waters as microorganisms utilize oxygen to break down the excess organic material.

Nutrient Concentrations

Elevated nutrient levels, particularly nitrogen and phosphorus, can intensify BOD pollution. These nutrients promote the growth of microorganisms that accelerate the decomposition of organic matter. The increased microbial activity results in a greater demand for oxygen, further contributing to oxygen depletion in water bodies.

Temperature Effects

Temperature plays a crucial role in microbial activity and the rate of organic matter decomposition. Warmer temperatures enhance the metabolic processes of microorganisms, causing them to consume oxygen at a faster rate. Consequently, higher temperatures lead to increased BOD levels in wastewater.

Common Sources of High BOD in Wastewater

The consequences of high BOD levels extend beyond the immediate pollution of water bodies.

Oxygen Depletion

As microorganisms consume oxygen during organic matter decomposition, the available oxygen in water bodies diminishes. This leads to oxygen depletion, which can harm aquatic organisms and ecosystems that depend on sufficient oxygen levels.

Harm to Aquatic Life

Low oxygen levels resulting from high BOD can suffocate fish and other aquatic organisms. Oxygen-deprived conditions disrupt the natural balance of aquatic ecosystems, leading to fish kills and reduced biodiversity.

Eutrophication

High BOD is often linked to nutrient pollution, which can trigger eutrophication. Nutrient-rich waters stimulate excessive plant growth, leading to algal blooms. As algae die and decompose, oxygen depletion intensifies, further exacerbating the BOD problem.

Conclusion

Where a company like MAC Water Technologies can REALLY help you is determining if another process can reduce COD or BOD faster, and in a more economical way than aerobic digestion.

Many times, the high operating costs associated with aerobic digestion can easily be reduced. Then you can polish the wastewater using aerobic digestion instead of having aerobic digestion be the primary removal method.

Contact us today for more information on how we can provide you with top-line wastewater treatment solutions.