Optimizing Nitrogen Removal in Meat & Poultry Product (MPP) Wastewater with Continuous Total Nitrogen (TN) Analysis

The US Environmental Protection Agency (EPA) released proposals in 2023 for new effluent limit guidelines (ELG) for meat and poultry product (MPP) facilities that require reductions of nutrients and other pollutants into water bodies and publicly owned treatment works (POTWs) (1). The European Union (EU) published its best available technologies (BAT) for Slaughterhouses, Animal By-Products and/or Edible Co-Product Industries for wastewater emissions in 2023 (2). These guidelines include approved technologies for pollution monitoring and nitrogen limitations to protect the surrounding bodies of water from excess nutrient discharge.

Nitrogen content in MPP wastewater can be represented based on a specific species of nitrogen (such as nitrate, nitrite or ammonia) or as a sum parameter (which would include all the nitrogen species) known as total nitrogen (TN).  Monitoring the influent and effluent wastewater for TN during the nitrification/denitrification process helps ensure optimal performance of nitrogen removal from MPP wastewater. To ensure wastewater treatment processes such as nitrification and denitrification are removing nitrogen efficiently, the Sievers TOC-R3 Online Total Organic Carbon (TOC) and TN Analyzer is a continuous analyzer that can monitor TN, providing real-time data. 

In 2019, MPP facilities in the United States released more than 28 million pounds of nitrogen from their wastewater into nearby rivers and streams as the largest industrial contributor of nitrogen pollution (1). The Environmental Integrity Project (EIP) investigated 98 meat processing facilities in the US and their EPA records from January 2016 to June 2018. This is a portion of the report:

“.... 74 of these facilities exceeded their permit limits for nitrogen, fecal bacteria or other pollutants at least once, more than half the facilities (50 out of 98) had five violations and one third (32 of the 98) had at least 10 violations during that time period.” (2)

These exceedances from meat processing plants have gained national attention. In 2023 the EPA proposed new effluent limitations guidelines (ELGs) for MPP facilities detailing their list of pollutants of concern, their parameters for regulation, wastewater treatment technologies to prevent pollution, pollutant loadings and standards. Among the list of pollutants, the new proposition will require MPP facilities to monitor nitrogen in their wastewater effluent to ensure it is safe to discharge to the local waterways. This proposal is scheduled to be finalized by 2025.

The EU established best available technologies (BAT) for Slaughterhouses, Animal By-Products and/or Edible Co-Product Industries to safeguard environmental health through recommendations for treatment and effluent monitoring guidelines. BAT are techniques or technologies approved by governmental legislators that are used to control and monitor for pollutants for environmental protection. This reference document recommends key monitoring parameters and locations, and suggests the use of total organic carbon as a BAT over Chemical Oxygen Demand because TOC does not use hazardous chemicals. Similarly, TNb or the sum of free ammonia, ammonium, nitrites, nitrates, and organic nitrogen compounds is a useful tool for meeting discharge requirements.

While composition of wastewater depends on individual MPP facility practices, nitrogen content in wastewater is consistently high across all of them. The primary form of nitrogen in MPP wastewater is in the form of ammonia, which is formed during the rendering process. The current tool for determining nitrogen removal in MPP wastewater is Total Kjeldahl Nitrogen (TKN).

While this method is universally adopted, has high precision and good reproducibility, it cannot detect nitrate or nitrite compounds, and it is not capable of continuous online measurement of wastewater treatment processes. To ensure that the MPP wastewater treatment systems (such as nitrification and denitrification) are properly removing nitrogen, an instrument is needed that is robust enough to handle complex sample matrices and able to measure wastewater continuously. This will be key to successfully meeting the proposed EPA regulations.

The Sievers TOC-R3 Online TOC and TN Analyzer determines TN content in a single measurement using an electrochemical detector (ECD). The Sievers TOC-R3’s ECD detects nitrate, nitrite, ammonia and other nitrogen compounds as a sum measurement in Total bound Nitrogen (TNb) mode. Within minutes, MPPs can quantify the total nitrogen content in effluent wastewater streams and determine their treatment efficiency. The Sievers TOC-R3 analyzer offers simple maintenance, low cost of ownership and the ability to make data-driven decisions in real time. 

Regulation changes for MPP facilities are rapidly approaching and these facilities need to ensure their wastewater treatment processes are removing nitrogen to meet the proposed EPA limits. The Sievers TOC-R3 can continuously monitor nitrogen removal in wastewater treatment to ensure treatment performance in real time. This allows operators to immediately take action if the treatment train is not removing nitrogen to the efficiency it needs to.

Author: Sara Speak

Sara Speak is a Product Application Specialist with Veolia Water Technologies & Solutions, providing support and application expertise to Sievers Analytical Instruments customers in industries such as chemical, petrochemical, food & beverage, and municipal wastewater. 

Sara works with customers to provide training, support product installations, optimize equipment use, and demo feasibility across different testing applications. Prior to her current role, she was a Factory Service Technician, responsible for repairing and troubleshooting Sievers instruments. Sara previously worked in the food and beverage industry as a QA Laboratory Technician at MillerCoors and Leprino Foods. She holds a Bachelor of Science (B.S.) in Chemistry and a Bachelor of Music (B.M.) in Violin Performance from Metropolitan State University of Denver.

References

1. Meat and Poultry Products Effluent Guidelines - 2024 Proposed Rule. 3/27/2024. https://www.epa.gov/eg/meat-and-poultry-products-effluent-guidelines-2024-proposed-rule. Accessed on 04/23/2024.
2. Official Journal of the European Union. Commission Implementing Decision (EU) 2023/2749 of 11 December 2023 establishing the best available techniques (BAT) conclusions, under Directive 2010/75/EU of the European Parliament and of the Council on industrial emissions, for slaughterhouses, animal by-products and/or edible co-products industries (notified under document C(2023) 8434). https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=OJ%3AL_202302749 Accessed on 04/18/2024.
3. Ridlington, Elizabeth and Weissman, Gideon. Slaughterhouses are Polluting Our Waterways. The Public Interest Network, Toxic Threats, 02/05/21. https://publicinterestnetwork.org/resources/slaughterhouses-are-polluting-our-waterways/ Accessed on 03/21/24.
4. Pelton, Tom. Three Quarters of Large U.S. Slaughterhouses Violate Water Pollution Limits. Environmental Integrity Project, 10/11/2018. https://prairierivers.org/uncategorized/2018/10/three-quarters-of-large-u-s-slaughterhouses-violate-water-pollution-permits/ Accessed 02/07/2024.
5. Animal Legal Defence Fund. EPA to Publish Slaughterhouse Water Pollution Standards Following Lawsuit. 03/01/2023. https://aldf.org/article/epa-to-publish-slaughterhouse-water-pollution-standards-following-lawsuit/ Accessed on 08/25/2023.
6. Bustillo-Lecompte, Ciro, Mehrvar, Mehrab and Quiñones-Bolaños, Edgar. Slaughterhouse Wastewater Characterization and Treatment: An Economic and Public Health Necessity of the Meat Processing Industry in Ontario, Canada. Journal of Geoscience and Environment Protection, Vol.4 No.4, 2016. https://www.scirp.org/journal/paperinformation.aspx?paperid=66462 Accessed on 08/25/2023.
7. Kundu, Pradyut, Debsarkar, Anupam and Mukherjee, Somnath. Treatment of slaughterhouse wastewater in a sequencing batch reactor: performance evaluation and biodegradation kinetics. Biomed Res Int. 2013;2013:134872. doi: 10.1155/2013/134872. Epub 2013 Aug 20. PMID: 24027751; PMCID: PMC3762084. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3762084/ Accessed on 08/25/2023.
8. Al-Juboori, Raed A., Al-Shaeli, Mauyad, Aani, Saif Al, Johnson Daniel and Hilal Nidal. Membrane Technologies for Nitrogen Recovery from Waste Streams: Scientometrics and Technical Analysis. Membranes (Basel). 2022 Dec 22;13(1):15. doi: 10.3390/membranes13010015. PMID: 36676822; PMCID: PMC9864344. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9864344/#:~:text=The%20most%20common%20nitrogen%20form,of%20the%20slaughtering%20process%20train. Accessed on 02/20/2024.