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Partial nitritation anammox (PNA) membrane-aerated biofilm reactors (MABRs) can be used in mainstream nitrogen removal to help facilities reduce their energy consumption. Previous PNA MABR research has not investigated the impacts of staging, i.e. arraying MABRs in series, on their nitrogen removal performance, operation, and ability to suppress nitrite oxidizing bacteria. In this paper, a mathematical model simulated PNA MABR performance at different influent total ammonia concentrations and loadings. A design methodology for staging PNA MABRs was created and found that the amount of membrane surface area is dependent upon the total ammonia-nitrogen concentration and loading, and the air loading to the membrane must be proportional to the total ammonia-nitrogen loading to maximize the total inorganic nitrogen (TIN) removal rate. This led to approximately equal-sized stages that each had a TIN removal percentage of 71% of the influent total ammonia nitrogen. Staging a treatment train resulted in 9.8% larger total ammonia and 9.3% larger total nitrogen removal rates when compared with an un-staged reactor. The un-staged reactor also was not able to produce an effluent total ammonia concentration below 5 mg N/L which would be necessary for many facilities’ permits.

 

Removal of pharmaceuticals in source-separated urine is an important step toward gaining acceptance of urine-derived fertilizers among important stakeholders such as consumers, farmers, and regulatory agencies. Advanced oxidation processes (AOPs) have been studied for the removal of pharmaceuticals in various complex matrices, including treated wastewaters. A complexity associated with AOP methods that rely primarily on hydroxyl radicals as the oxidizing agents is that they readily lose effectiveness in the presence of scavengers. Here, we investigated the potential for capturing the synergistic effects of producing multiple oxidative chemical species simultaneously in a plasma reactor to oxidize six pharmaceuticals (acetaminophen, atenolol, 17α-ethynyl estradiol, ibuprofen, naproxen, and sulfamethoxazole) in source-separated urine being processed into a fertilizer. The results show that the plasma reactor produced hydroxyl radicals as the primary oxidizing agent and the effects of other oxidizing species were minimal. Plasma experienced scavenging in both fresh and hydrolyzed urine; furthermore, it oxidized pharmaceuticals at similar rates across both matrices. Additionally, the negative impacts of electrical discharge formation stemming from increased solution conductivity appeared to plateau. The energy required per order of magnitude of pharmaceutical transformed was up to 2 orders of magnitude higher for plasma than for a traditional UV/H 2 O 2 reactor and depended upon the matrix. Despite scavenging and energy concerns, plasma can oxidize pharmaceuticals in fresh and hydrolyzed urine and is worthy of further development for on-site or building-scale applications where the value of convenience, simplicity, and performance offsets energy efficiency concerns. 

Pharmaceuticals and personal care products (PPCPs) can enter agricultural fields through wastewater irrigation, biosolid amendments, or urine fertilization. Numerous studies have assessed the risk of PPCP contamination, however there are no standardized methodologies for sample treatment, making the interpretation of results challenging. Various time periods between sampling and analysis have been reported (shipping, storage, etc. ), but literature is lacking in the evaluation of PPCP degradation amidst this process. This study assessed the stability of 20 pharmaceuticals (200 μg L −1 ) in soil and crops stored at −40 °C for 7, 30, and 310 days. After 310 days, caffeine, meprobamate, trimethoprim, primidone, carbamazepine, anhydro-erythromycin and dilantin were found to be stable (≥75% recovery) in all matrices. On the other hand, acetaminophen, amitriptyline, bupropion, lamotrigine, sulfamethoxazole, naproxen, ibuprofen, and paroxetine were unstable after 30 days in at least one of the matrices investigated. Due to variations in analyte stability, fortification with isotopically-labelled surrogates at the point of sample collection was evaluated in comparison to fortification after shipment and storage, immediately prior to extraction. Chromatographic peak areas of stable analytes were found to be reproducible (±15%) in field-fortified samples, indicating that no additional error occurred during sample handling under field conditions despite having a less controlled environment. Unstable analytes revealed notable differences in peak areas between fortification times, suggesting that fortification immediately after sample collection is crucial to account for analyte losses during shipping and storage, resulting in accurate quantification of PPCPs. 

Ensuring long-term access to nutrients needed for food production is a growing global challenge. Human urine diversion and recycling is a viable and energy-efficient means of recovering nitrogen, phosphorus, and potassium from wastewater. Before implementation, however, it is critical to understand how communicating differently about human urine-derived fertilizer may influence its public acceptance. This study tests how different strategies of communication (video compared to texts), as well as different amounts of information, impact public acceptance. We also explored how specific characteristics, such as age and education level, may impact the usefulness of the different strategies of communication. The results indicate that short and long videos are the most useful risk communication strategies, and age fully moderates this relationship. This research may serve as a jumping off point for future studies focused on how risk communication strategies may affect consumer acceptance of other emerging food technologies. 

This research investigates medium‐scale disruptive events to understand how these events influence communication and coordination between two interdependent systems (i.e., the water system and the public health system). Medium‐scale events are events that are often overlooked as routine as they occur with more frequency than large‐scale events, yet they have the potential to provide important information about the state and vulnerability of systems, and, if not managed appropriately, can cascade into larger‐scale crises. A survey of US public drinking water systems (N = 471) shows that medium‐scale events promote coordination, especially when those events have a public dimension. Findings also reveal that several features of water systems including surface water sources, system size, and ownership types are associated with higher levels of interaction with the public health systems. Additionally, a network analysis identifies three distinct subnetworks that engage in emergency response activities. The strength of the working relationship was strongly associated with coordinated emergency responses, coordinated public responses, planning, and technical assistance. Findings have implications for both theory and crisis management.

 

This paper reports on social research investigating perceptions concerning the diversion of urine from the waste stream and its use as fertilizer in two study regions, New England and the Upper Mid­west. We hypothesized that discomfort or disgust might affect acceptance of such a shift in human “waste” management. However, our findings suggest that a more significant concern of those potentially involved in this process may be distrust of how economic interests influence scientific and technical information. Both physical risks (to the environment and public health) and socio-political risks (to fragile farm economies and consumer communities) play out at individual, household, regional, and global scales. We describe the intersection of these complex understandings as nested risks and responsibilities that must inform the future of urine reclamation. Our respondents' shared concern about environmental risks has already galvanized communities to take responsibility for implementing closed-loop alternatives to current agricul­tural inputs and waste management practices in their communities. Attention to these nested understandings of both risk and responsibility should shape research priorities and foster participatory approaches to urine nutrient reclamation, including strategies for education, planning, regulation, technology design, and agricultural application.