Meadow Lake Mechanical Pulp (MLMP), a subsidiary of Paper Excellence, confronted pressing water quality concerns, manifested in elevated Chemical Oxygen Demand (COD) levels, green coloration, and persistent odors. To tackle these issues, a 6-month trial was initiated employing EnBiorganic Technologies process that includes proprietary microbiology and the EBS-Di system, a microbial generator and dispensing unit. The pilot aimed at a 30% reduction in COD from a baseline of 843 ppm and qualitative improvements in water clarity and odor. Despite challenges, such as the proliferation of Chlamydomonas algae exacerbated by traditional nutrient enrichment strategies to support indigenous microbial growth, the trial culminated in a marked reduction in COD levels. The EBS-Di treatment demonstrated an average of 395 ppm COD in the final six weeks (a >50% reduction in COD compared to the baseline), along with notable qualitative improvements, marking the endeavor a success and highlighting the potential of innovative bioaugmentation treatment methodologies in the Pulp and Paper industry.
Meadow Lake Mechanical Pulp (MLMP), a subsidiary of Paper Excellence, operates Canada‘s only pulp facilities that operate with zero liquid discharge. Instead of releasing wastewater into local water bodies, the mill recycles it, positioning MLMP at the forefront of water conservation in an industry under pressure to reduce water usage. The facility handles over 6500 cubic meters daily.
The Paper Excellence mill faced water quality issues characterized by elevated Chemical Oxygen Demand (COD) levels, green coloration, and persistent odors. These factors negatively impacted the plant‘s reuse process and potentially, the quality of the pulp produced. In light of these issues, a technological intervention was considered necessary to improve water quality and, by extension, safeguard product quality.
EnBiorganic Technologies (EnBiorganic), was engaged after MLMP had attempted using traditional bioaugmentation, wherein a limited amount of spore-state microbes were purchased and applied periodically throughout the week.
EnBiorganic‘s EBS-Di system, a microbial generator and dispensing unit, was selected to address the identified water quality concerns. The EBS-Di differs from traditional bioaugmentation products and services because it is capable of autonomously generating and dispensing up to 720 litres of active state microbiology each day continuously throughout the entire service
period. These active state Bacillus microbes are adapted to the wastewater stream directly through the patents-pending processes of the EBS-Di. All the Bacillus used are certified organic and ubiquitous soil bacteria, making them not only very safe for pulp and paper wastewater but also very effective as they are natural born consumers of the organics in those streams.
To assess the system‘s applicability and performance in the distinct environment of pulp and paper wastewater, a structured 6-month trial was initiated. The trial was designed to provide MLMP with empirical evidence of the system‘s effectiveness before any financial commitments were made. This approach allowed for a comprehensive evaluation of the technology‘s suitability for treating the specific wastewater challenges faced by MLMP.
Objectives and EnBiorganic Solution
The trial demonstration at MLMP was established with a clear set of objectives, or Critical Success Factors (CSFs), that emerged from the pressing concerns about water quality at the facility. The demonstration was structured around a primary quantitative metric: the reduction of COD levels. A clearly defined performance target was set – achieving a 30% reduction from the established baseline of 843 ppm COD for at least the final 6-week of the demonstration period. This translated to bringing down the COD levels to 601 ppm or lower, providing an objective measure to evaluate the efficacy of the intervention.
In addition to this quantifiable target, the trial also emphasized subjective improvements. These encompassed enhancements in water clarity, which was marked by green coloration from algae, and problematic odors. Achieving these qualitative goals was equally crucial, as they directly impacted the operational efficiency and perceptible quality of the pulp produced.
Recognized for its capabilities in the municipal wastewater sector, the application of the EBSDi system in the unique environment of pulp and paper wastewater was seen as a potential solution to MLMP‘s water quality concerns. The methodology for addressing the water quality concerns at MLMP was carefully structured, grounded in the application and monitoring of EnBiorganic‘s EBS-Di units. Two EBS-Di units were commissioned on the 7th of March 2023, where they were set to continuously dispense microbiology. Averaging up to 2,000 liters daily.
Methodology and Results
The pilot study produced notable results, both quantitatively and qualitatively, demonstrating the efficacy of the EBS-Di units in treating the wastewater concerns at MLMP.
The quantitative assessment is based on weekly sampling and analysis taken directly from the MLMP wastewater lagoons. MLMP has three lagoon cells or ponds called DEP 1, DEP 2, and WSR. The effluent mill water flows into Distillate Equalization Pond (DEP) 1 then to DEP 2, and then to the Water Storage Reservoir (WSR). The mill draws process water from the WSR. Since the WSR is the primary source of the reuse water system, it was the most prudent place to take regular samples for the COD. The COD, therefore, discussed in this assessment refers to the COD of the WSR. Essential to the assessment of this trial was MLMP’s historical or baseline WSR COD data which is gathered for process monitoring purposes on a weekly basis.
The trial period yielded a 6-month average COD level of 582 ppm, which was a 31% decrease from the baseline measurement of 843 ppm. As demonstrated in Figure 1, during the final 6-weeks of the trial period the COD levels dropped to an average of 395 ppm. Meaning an average of 53% COD reduction, surpassing the performance target and illustrating the potential for the system‘s long-term effectiveness.
Qualitatively, MLMP observed transformative changes in the wastewater‘s characteristics. The water, once tainted with a greenish hue, indicative of algae proliferation and associated problems, now exhibited enhanced clarity and absence of color. Figure 2 shows the algae that initially proliferated inside the EBS-Di with no exposure to sunlight, which was unique and aided in identifying this incredibly resilient algae. The color shown is also a glimpse of the watercolor of the WSR when this photo was taken around the 30-day mark of the trial. Additionally, the odors were also substantially reduced.
These outcomes—both the substantial drop in COD levels and the perceptible improvements in water aesthetics and odor—served as clear indicators of the project‘s success. The dual achievement, in meeting and exceeding the objective target while also addressing the qualitative concerns, underscored the holistic impact on the reuse water. It reaffirmed that application of the EnBiorganic process can solve even persistent and complex wastewater challenges, such as those faced by MLMP.
During similar months of the previous year, a noticeable decrease in COD levels was observed, as depicted in Figure 3. One significant factor to consider is the behavior of the indigenous microbes in the mill’s wastewater. These microbes struggle in cold water, especially once they move beyond aeration sections. As water temperatures approach 4°C, most microbes become inactive. However, EnBiorganic microbes continue to operate at reduced speeds down to freezing, compensated by their larger populations and continuous application by the EBS-Di. The Bacillus dispensed by the EBS-Di are also facultative, allowing for uninterrupted performance.
It is important to note that technical staff at MLMP observed green and odorous water despite the lower COD levels in 2022. A marked difference in 2023 where even lower COD levels were achieved along with improved water clarity and less odors.
Figure 4 shows this comparison directly, contrasting the same time of year for both 2022 and 2023. The blue line shows the EnBiorganic treatment period, which stays steadily below the 2022 line in grey. In the final 6 weeks of the 2022 and 2023 time periods, the gap reduces and at one-point overlaps. Yet, the averages of that same 6-week period show 501 ppm for 2022 and 395 ppm for the EBS-Di treatment period in 2023. This is a 22% percent difference.
Despite the correlated trends between 2022 and 2023 data, the fact remains that EBS-Di had impact on the qualitative CSFs of the trial. Taking those qualitative successes along with the quantitative points to fact that EnBiorganic demonstrated its efficacy in the pulp and paper wastewater recycling process. Furthermore, the trial period‘s 6-month average COD level of 582 ppm and the 395 ppm during the final six weeks outperformed the previous year‘s metrics during the same timeframe. This demonstrates that the EBS-Di system played a pivotal role in achieving these lowered levels. While it‘s essential to acknowledge natural variations in COD levels due to operational factors, the marked improvements during the EBS-Di trial period attest to its effectiveness and potential for broader application.
The execution of the EBS-Di trial demonstration at MLMP was not without challenges, the most prominent of which was the unexpected proliferation of Chlamydomonas algae. Chlamydomonas is a type of green alga known for its adaptive capabilities, making it particularly tenacious in diverse environments. What caught the attention of the project team was the algae‘s resilience to thrive even in environments with limited sunlight, a characteristic not typically expected given its photosynthetic nature.
Compounding this challenge was MLMP‘s established treatment strategy that involved the enrichment of wastewater ponds with Nitrogen and Phosphorus. These nutrients, while essential for traditional pulp paper mill treatment processes, inadvertently served as fuel for the rapid growth of the algae.
Identifying the specific algae and recognizing the correlation between the nutrient addition and algal proliferation, EnBiorganic recommended around the 40-day mark of the trial to stop the nutrient addition because EnBiorganic’s microbiology did not need the added nutrients like traditional microbiology. MLMP agreed and decided to discontinue the addition of Nitrogen and Phosphorus to their treatment ponds.
This move proved decisive. Post the cessation of nutrient enrichment, there was a noticeable decline in the algae populations, which consequently led to a marked reduction in COD levels. EnBiorganic’s microbiology produces enzymes that impede growth and life of the algae so they can use it for food and nutrients to support facultative growth. This adaptive strategy not only mitigated a major challenge but also reinforced the importance of a holistic understanding of wastewater treatment processes, emphasizing the need to regularly reevaluate and adjust treatment strategies in light of emerging challenges.
The trial demonstration between MLMP and EnBiorganic, utilizing the EBS-Di system, aimed to address the challenges of deteriorating water quality, particularly concerning COD levels. Despite unforeseen challenges, such as the unexpected growth of Chlamydomonas algae amplified by MLMP‘s initial treatment approach, adaptive measures ensured the project‘s success. A strategic pivot to curtail nutrient addition resulted in a notable 6-month average COD of 582 ppm. In addition, in the final 6 weeks of the trial, which served as the final assessment period, a 53% COD reduction was achieved. Beyond this quantitative success, observable enhancements in water clarity and odor further underlined the project‘s effectiveness. Both organizations, through collaborative efforts and innovative solutions, not only met their goals but also highlighted the potential of the EBS-Di system for wider industrial applications.
The success of this venture is a testament to the collaborative spirit and innovation displayed by both MLMP and EnBiorganic. Given the successful outcome and achievement of critical success factors agreed upon prior to the start of the trial, MLMP has now committed to the continued use of the EBS-DI system based on a monthly service fee. The company’s willingness to embrace a novel and environmentally conscious solution speaks volumes about their commitment to sustainable practices.