Use of Biostimulants and Buffers for Upset Recovery in Paper Mill Wastewater Systems

By Heather Jennings, PE

Industrial pulp and paper wastewater is considered one of the more challenging waters to treat using biological methods, which depend on microbial activity to effectively remediate the wastewater.

Wastewater treatment systems are often influenced/impacted by increased hydraulic and/or COD (chemical oxygen demand) loading as mills add new chemicals or otherwise modify mill operations. These events oftentimes inhibit the wastewater microbial activity, causing “upsets” and, potentially, discharge-limit violations. However, providing the necessary biostimulants and buffers to the microbial system—as we describe in this case study from a paper mill in China—can significantly improve system-upset recovery time and overall operational stability. Continue Reading

Breaking Down COD

By Heather Jennings, PE 

When I first came into the water field in the 2000s, the general rule of Chemical Oxygen Demand to Biochemical Oxygen Demand (or COD to BOD5) was 2:1. That was pretty much all you needed to know in order to understand whether something could be treated chemically, physically, or biologically. Now, the wastewater industry has moved toward COD instead of BOD5. The reason that COD is sometimes preferred is that BOD5 doesn’t take into account the organics that become biomass nor the non-biodegradable carbonaceous matter. COD can also be evaluated in the field with simple test kits, whereas most operators must send their BOD5 tests to third-party labs and wait weeks for results.   [Read more…]

Translate »
>