Urine Diversion Research Articles

Recovery of N and P from Urine by Struvite Precipitation Followed by Combined Stripping with Digester Sludge Liquid at Full Scale

A novel ammonia stripping method, including a CO2 pre-stripper was used to treat a mix of supernatant liquor from an anaerobic digester and urine in order to recycle nitrogen as ammonium sulfate at full-scale in the WWTP Kloten/Opfikon. Waste streams were not generated, since the ammonia was recovered as a marketable nitrogen fertilizer, turning a waste product into a valuable product. The efficiency of this system was increased by means of the addition of pre-treated urine collected separately at EAWAG building. The separation step was performed by the use of water free urinals and urine diversion flush toilets. An increase of 10% in the liquid flux with the addition of the urine translated into a 40% increase of the ammonia concentration in the inlet of the stripping unit. The achievement of these percentages generated a proportional increase in the fertilizer production. The urine pre-treatment was carried out by adding magnesium to produce a precipitate of struvite. The first experiments with the combined treatment showed the feasibility of the combination of the separation and pre-treatment steps.

Sustainable innovation in wastewater management: lessons for nutrient recovery and reuse

Urine diversion (UD) has great potential to contribute to sustainably managing wastewater by separating urine at the source and recovering nutrients for reuse in agriculture. While factors enabling the UD technology in Sweden are thought to involve policies supporting nutrient recovery/reuse, on closer inspection, the variable success of UD systems has revealed that critical factors for success also relate to human-centred issues of social organisation, participation and incorporation of social knowledges of a variety of stakeholders into the decision-making process in which new technologies are trialled and adopted. Through the analytical lens of strategic niche management, we consider how early experimentation in UD has involved user participation and whether internal processes of learning, networking and visioning have been consciously considered and to what effect. As niche experiments are enabled/disabled not only by informal institutions such as values and social norms but also formal regulatory institutions, we have concurrently analysed the broader environment in which policies and institutions influence, to varying degrees, the uptake of UD.

Assessment of urine diverting dehydrating toilets as a flood-resilient and affordable sanitation technology in the context of Bangladesh

Bangladesh has made a significant contribution to supply improved sanitation facilities in rural areas in recent years. As it is the most known option, pit latrines were the most favourable technology. Yet, as Bangladesh is a country of flooding and high groundwater table, pit latrines not only flush out and cause pollution; they also become inaccessible during floods, and remain filled with silt after the floods. Every year floods destroy many sanitation facilities and force people to resort to open defecation, despite the capital-intensive investment. Urine Diversion Dehydration Toilets (UDDTs) were evaluated on their suitability in flood-prone areas and their affordability in the context of Bangladesh. A survey conducted in two flood-prone areas of Bangladesh showed that with an average height of 0.69 m the UDDTs are higher than the average highest flood level of 0.31 m. To decrease cost and construction complexity, a local design was developed based on the current pit latrine, at 50% of the costs of the current UDDTs. Although the resulting cost is still not within reach for most Bangladeshi, the affordability could be increased by taking into account avoided emptying costs as well as the added value of human excreta as a fertilizer.

User perceptions of urine diversion dehydration toilets: Experiences from a cross-sectional study in eThekwini Municipality

The current environmental challenges that most middle- and low-income countries have been experiencing has led to new environmentally sustainable and economically viable sanitation solutions, such as waterless systems with source separation of human waste. We conducted a cross-sectional study in eThekwini municipality to explore the post-implementation challenges of urine diversion dehydration toilets (UDDTs) after a decade of installation and the adaptive processes necessary to increase the sustained use of the toilets. A structured questionnaire was administered to 17 499 households in 65 rural and per-urban areas of eThekwini using mobile phone technology. Results report low levels of satisfaction with the facilities as well as an association between perceived smell in the toilets and malfunctioning of the pedestal, and low use of UDDTs when a pit latrine is present in the dwelling perimeter. Conclusions relate to the importance of educational and promotional activities that stress the economic return derived from reusing urine and excreta in agricultural activities.Keywords: Sanitation, urine diversion toilets, user satisfaction, South Africa

Rectal impalement with bladder perforation: A review from a single institution

Context:Impalement injuries of the rectum with bladder perforation have been rarely reported. Such lesions have been associated with increased postoperative morbidity. A well-conducted preoperative evaluation of the lesions tends to prevent such complications.Aims:To increase awareness about patients with rectal impalement that involve bladder injuries and to examine the significance of thorough clinical examination and complementary investigation for these patients’ management.Materials and Methods:Retrospectively, we identified three patients with rectal impalement and bladder perforation treated in University Hospital Hassan II, Fez, Morocco. We recorded the symptoms, subsequent management, and further follow-up for each patient. All available variables of published cases were reviewed and analyzed.Results:Evident urologic symptoms were present in only one patient. Bladder perforation was suspected in two other patients on the basis of anterior rectal perforation in digital exam. Retrograde uroscanner could definitely confirm the diagnosis of bladder perforation. Fecal and urine diversion was the basis of the treatment. No postoperative complications were noted. We have reviewed 14 previous reports. They are presented mainly with urine drainage through the rectum. Radiologic investigation (retrograde cystography and retrograde uroscanner) confirmed bladder perforation in 10 patients (71.4%). Unnecessary laparotomy was performed in six patients (42.8%). Fecal diversion and urinary bladder decompression using urethral catheter were the most performed procedures in bladder perforation [6/14 patients (42.8%)]. No specific postoperative complications were reported.Conclusions:A high index of clinical suspicion is required to make the diagnosis of bladder perforation while assessing patients presenting with rectal impalement. Meticulous preoperative assessment is the clue of successful management.

Development of a Fully Automated Struvite Reactor to Recover Phosphorus from Source Separated Urine Collected at Urine Diversion Toilets in eThekwini

Development of a Fully Automated Struvite Reactor to Recover Phosphorus from Source Separated Urine Collected at Urine Diversion Toilets in eThekwini

A Decision Support Methodology for Integrated Urban Water Management in Remote Settlements

This paper describes a decision support methodology for the selection of a wastewater treatment system based on integrated urban water management principles for a remote settlement with failing septic systems. Thirty-two service and treatment technologies options were considered, these included: (i) conventional gravity sewerage, (ii) common effluent drainage, (iii) community sewage treatment plant based on various technology options (lagoon treatment, Living Machine®, sequencing batch reactor, membrane biological reactor, rotating biological contactor, recirculating textile filter, extended aeration) with and without urine separation, greywater diversion or treatment and reuse at household scale. The options were assessed using a framework that considered technical, economic, environmental and social factors relevant to the local community and associated stakeholders (water utility, government agencies) and tools such as engineering design, life cycle assessment and multi-criteria analysis for evaluation of overall sustainability. Adoption of a systems approach allowed the identification of benefits and trade-offs among stakeholders creating opportunities for adoption of more innovative treatment options and maximisation of the sustainability of the service. The treatment option that maximised the social, environmental and economic benefits for the settlement consisted of individual households adopting greywater treatment, storage and reuse, urine separation and a community wastewater treatment plant with recirculating textile filter technology. This solution provided the required sanitation, increased the sources of water supply to residents, satisfied environmental regulator requirements, minimised nitrogen discharge to waterways and provided an option for beneficial reuse of urine for neighbouring farmers at a cost and management needs acceptable to the water utility.

Pathways and Management of Phosphorus in Urban Areas

SummaryDue to the finite nature of mineral phosphorus reserves, effective management of anthropogenic phosphorus flows is currently under investigation by the international research community. This article emphasizes the importance of urban phosphorus flows, which are often marginalized due to the greater magnitude of agricultural phosphorus flows. A study on phosphorus flows in Gothenburg, Sweden, points out the potential role of solid waste in nutrient management, as the amounts of phosphorus in solid waste and in wastewater were found to be equal. Importation of food commodities accounts for 50% of the total inflow of phosphorus, and food waste is a major contributor of phosphorus to solid waste. The results suggest that solid waste incineration residues represent a large underestimated sink of phosphorus. Focusing on wastewater as the sole source of recovered phosphorus is not sufficient. The Swedish national goal on phosphorus recycling, which is limited to sewage sludge, targets only a part of the total phosphorus flow that can potentially be recovered. In contrast to previous studies, agricultural flows in Gothenburg were marginal compared to flows related to the urban waste management infrastructure. We emphasize the need for debate on preferable routes for disposal of waste with a high phosphorus content. Both recovery potential and usefulness of the recovered product for agricultural purposes have to be considered. Impacts of five waste management strategies on phosphorus flows were evaluated: incineration of all the waste, comprehensive food waste separation, installation of kitchen grinders, urine diversion, and separation of blackwater and food waste.

Stabilization of source-separated urine by biological nitrification process: treatment performance and nitrite accumulation

A laboratory study on nitrification of high-strength source-separated urine was conducted by means of sequencing batch reactors (SBR) and membrane bioreactors (MBR). The highest influent ammonia concentration for SBR and MBR reached more than 2,400 and 1,000 mg N/L, while the maximum pH was about 9 and 8.9, respectively. The ammonia oxidizing efficiency in both SBRs and MBRs was around 50%, which was restrained mainly by the deficiency of alkalinity in bulks. Meanwhile, the nitrite accumulation did also dominate in these two systems, and the major factor to inhibit the nitrite oxidization was thought to be the high free ammonia and free nitrous acid content in bulks. Hence, an ammonia nitrite solution was achieved with concentration ratio of 1:1; after that ammonia oxidation was restrained owing to the deficiency of alkalinity in urine. The temperature and influent ammonia content have no great influence on the nitrification process in both kinds of bioreactors. The nitrification can be progressed under a solids retention time (SRT) longer than 30 d; however, termination of ammonia oxidization was observed as the SRT fell below 20 d. The nitrifier biomass showed an excellent settleability, such that the suspended solids (SS) in effluent was of a low average, about 60 mg/L. This study on the stabilization of human urine will be useful to understand the process of urine separation from source.

A New World Ordure? Thoughts on the use of Humanure in Developed Cities

The implementation of urban farming through fertilisation with human excreta (humanure) has been a recurring agricultural technique. This concept paper discusses the challenges involved in using humanure for urban farming specifically in the developed world. It takes a broadly actor-network approach to acknowledge these challenges and suggests possible directions for addressing them. First providing a brief overview of attitudes towards human excreta across cultures, particularly the dichotomous views of waste or resource, it then outlines the crucial development of water-based sanitation in England in the 19th century and the spread of this technology across the developed world. Next various techniques of humanure (human excreta) use in agriculture are introduced before a particular focus on the technique of urine diversion is proposed. Finally discussing the multi-scalar technical, health, social and above all cultural challenges facing the use of ‘humanure’ for urban agriculture in the context of developed cities, it then acknowledges the incremental nature of successful technology uptake before proposing one possible modest approach for addressing the difficulties implicit in this model through the use of ‘urine diversion’.

Assessment of social acceptance and scope of scaling up urine diversion dehydration toilets in Kenya

A urine diversion dehydration toilet (UDDT) is a kind of toilet which can be used to recover resources such as nutrients and can also be an option to improve the sanitary situation in low income countries. A structured questionnaire survey, key informant interviews, participatory approaches such as focus group discussion (FGD) and mass gathering were carried out in Kenya to assess social acceptance and scope of scaling up of UDDTs. The results showed that almost all respondents among UDDT users and non-users have overcome social and cultural barriers to accept UDDTs. Most UDDT users were applying UDDT products as fertilizers on their farms. It is recommended to promote coordination and networking of local community based organizations in order to replicate UDDTs.

Preservation of nutrients during long-term storage of source-separated yellowwater

Source separation of human urine (yellowwater) enhances the sustainability of wastewater management and efficiency of nutrient recovery and recycling. Storage of source-separated yellowwater is recommended prior to agronomic reuse. At this point, it is of immense interest to determine the effect of storage time on quality of yellowwater. Therefore, this study focused on examining changes in some chemical properties of raw, undiluted, freshly collected, source-separated yellowwater stored for a period of 1 year under different temperature regimes: cold (4 °C), mild (10 °C) and warm (22 °C). Chemical parameters (biochemical oxygen demand (BOD(5)), N-tot, N-NO(2), N-NO(3), N-NH(4), P-tot, K, S, and pH), with the main focus on fertiliser nutrient compounds intended for agricultural utilisation, were tested. The outcomes revealed that both nitrification and denitrification processes took place in the stored yellowwater, and an increase in the pH level of up to pH greater than 9 was observed. The study found that the main macronutrients can be well preserved in yellowwater, as there were no substantial changes in the contents of these elements over a 1 year storage period at the three temperatures tested.

Use of locking-loop pigtail nephrostomy catheters in dogs and cats: 20 cases (2004–2009)

To describe the procedure and clinical usefulness of locking-loop pigtail nephrostomy catheter (PNC) placement in dogs and cats. Retrospective case series. 16 cats (18 kidneys) and 4 dogs (4 kidneys) that underwent PNC placement. Medical records of patients that underwent PNC placement were reviewed. The PNCs were placed percutaneously with ultrasonographic and fluoroscopic guidance or via a ventral midline laparotomy with fluoroscopic guidance. Either a modified Seldinger technique or a 1-stab trocar introduction technique was used for PNC placement. Preoperative renal pelvic size, postoperative renal pelvic decompression, catheter patency, serum biochemical changes, and results of microbial culture of urine samples were reviewed. Length of time the catheter was in place, reason and method for catheter removal, complications, and clinical outcomes were noted. Reasons for PNC placement were ureterolithiasis (15 kidneys), ureteral stricture (3), malignant obstruction (2), and percutaneous nephrolithotomy (2). Seven of 22 catheters were placed percutaneously, and 15 were placed via a ventral midline laparotomy. Catheters were either size 5F (n = 17) or 6F (5). The PNCs remained indwelling for a median of 7 days (range, 1 to 28 days). Catheter-associated complications included urine leakage (n = 1) and accidental dislodgement by the patient at home (1). All catheters performed successfully by providing temporary urine diversion and drainage for successful renal pelvis decompression. Placement of locking-loop PNCs was safe, effective, and well tolerated in dogs and cats for temporary urine diversion to achieve renal pelvis decompression.

Ecological Sanitation in Morocco Promotion of the Urine-Diversion Dehydration Toilets-Case of Dayet Ifrah

Problem statement: Most of people in rural areas in Morocco don’t have adequate systems of collection, evacuation and transport of black and gray water. They simply defecate in nature. There is a huge demand, which cannot possibly be met by conventional sanitation systems due to the enormous costs of the pipe network, lack of water and serious environmental drawbacks in order to avoid the disadvantages of conventional wastewater systems. For this reason, we have thought to promote ecological sanitation, or “ecosan“ for short, that recognizes human excreta and water from households not as a waste but as resources that can be recovered, treated where necessary and safely used again. Ecosan is a philosophy which houses a multitude of different technologies applied in ecological sanitation projects such as Urine Diversion Dehydration Toilets (UDDT). Approach: The scope of the study was to highlight the ecosan promotion strategies and policies for its adoption by the future ecosan users in Morocco and to show that the development of ecosan pilot systems adapted to the sociocultural context of Morocco is possible and can be used as model for rural areas. Ecosan systems studied had been implemented in a small rural area in Morocco called “Dayet Ifrah”. But, it’s necessary at the beginning to sensitize people in Dayet Ifrah and to convince to adopt and accept urine diversion dehydration toilets. Marketing has been more successful than anything else in changing the behavior of people when they can see direct personal benefits. Choosing a (social) marketing approach means that the attractiveness of the product is one important factor. That was what happened in 2009. Results: After this phase of sensitizing, results reveal that the households were convinced of the benefits these infrastructures afford them. Ecosan reduces the health risks related to sanitation, contaminated water and waste, prevents the pollution of surface and groundwater, prevents the degradation of soil fertility and optimizes the management of nutrients and water resources. Conclusion: The users are satisfied with the ecosan approach to cleanse their wastewater. Our work shows that ecosan can succeed in very poor populations. It is particularly relevant as locomotors of agricultural economics.

An economic appraisal of using source separation of human urine to contain and treat endocrine disrupters in the USA

Elevated concentrations of estrogens in natural waters pose a significant threat to public health and aquatic ecosystems. Both natural (estrone, 17β-estradiol and estriol) and synthetic (17α ethynylestradiol) estrogens, ubiquitous in wastewater effluents and receiving waters, have been shown to affect the endocrine system of human and aquatic life. The effects vary from cancer to sex reversals at levels as low as parts per trillion in sensitive organisms. Separation of urine, which constitutes only about 1% of domestic sewage and contains nearly all of the excreted estrogens, potentially offers an energy-efficient way to contain and then treat these chemicals. With a capital expense of $2100 and operation and maintenance costs of $69 per year for a urine diverting toilet system, a family in the USA can realize estimated savings of $101 per year in energy, water, and nutrients and a decrease of 100 kg in greenhouse gas emissions. To remove 99% of estrogenicity in discharged waters would require approximately 12 kW h per year using continuous electrodialysis followed by ozonation (O(3)) of source separated urine. To achieve the same results by adding O(3) treatment after activated sludge at existing municipal wastewater treatment plants would require 23 kW h per year. From an energy standpoint it makes sense to practice source separation and treatment of urine to limit estrogen discharges into the environment.

Evaluation of in vitro gas production and nutrient digestibility of complete diets supplemented with different levels of thermotolerant yeast in Nellore rams

Aim: The objective of the present study was to know the effect of dietary supplementation of varied levels of thermotolerant yeast to determine best levels for sheep diets by in vitro gas production. An in vivo study on Nellore rams was used for further evaluation of diets with three best levels of yeast (obtained from in vitro data) to determine diet with optimum yeast level for growing lambs by assessing nutrient digestibility, plane of nutrition and nitrogen balance. Materials and methods: A complete diet was formulated and supplemented with five levels (0 g/kg (D ); 1 g/kg (D ); 2 g/kg 1 2 8 (D ); 3 g/kg (D ); 4 g/kg (D ) and 5 g/kg (D ) of thermotolerant yeast (Saccharomyces cerevisiae, OBV-9) @ 5x10 cfu/g to 3 4 5 6 determine best levels for sheep diets by IVGP technique. An in vivo study was conducted on Nellore rams (39.75 0.24 kg body weight, aged 3 years) in a 4 x 4 latin square design for further evaluation of diets with three best yeast levels based on in vitro data, to determine optimum yeast level for diets of growing lambs by assessing nutrient digestibility, plane of nutrition and nitrogen balance. The rams were housed individually in metabolic cages that allowed separation of urine and faeces to evaluate digestibility of nutrients and N balance. Animals were given 10 days adaptation period followed by 7-day collection period, feed intake and refusals were recorded. During the digestibility and N balance study, feed, refusals and faeces were analyzed for dry matter (DM), organic matter (OM) and crude protein (CP) as per AOAC, USA, while fibre fractions like neutral detergent fibre (aNDF) and acid detergent fibre (ADF) were analyzed. Data were analyzed as per the procedures suggested by Snedecor, G. W. and Cochran, W. G. (1994) and the difference between treatment means was tested for significance by Duncan's multiple-range and F Test. Results: Higher (P<0.01) IVGP volumes, in vitro organic matter degradability, metabolizable energy (ME) and total degradable organic matter were recorded for rations D to D over control, whereas the difference among D to D diets was not 2 6 2 4 significant. Significant (P<0.05) partitioning factor and efficiency of microbial biomass synthesis (EMBP) values for rations D and D and significant (P<0.01) microbial biomass production for D to D diets, recorded. Significant (P<0.01) nitrogen 2 3 2 6 (N) retention was recorded in yeast supplemented rations with high EMBP than control. Dry matter intake (DMI), DMI (% b. 0.75 wt.), DMI/kg W and the digestibility of dry matter, organic matter, crude protein, crude fibre, ether extract (P<0.05), nitrogen free extract and fiber fractions were significant (P<0.01) on rations D to D over control, while the difference among 2 4 rations D to D was not significant. All rams were in positive N balance and was higher (P<0.01) on rations D to D over 2 4 2 4 control. The digestible crude protein (DCP) and ME were higher (P<0.01) on rations D to D indicating all rams were 2 4 adequately met with DCP and ME requirements as suggested by ICAR, India. Conclusions: The present study demonstrated the potential of theromotolerant yeast at 1 g/kg to 3g/kg level in improving digestibility of nutrients, intake of DCP and ME and N retention without affecting health of rams under study. Thus, incorporation of 1 g/kg level of thermotolerant probiotic yeast in complete diet for lambs appears to be beneficial for livestock producers.

Source Separation of Urine as an Alternative Solution to Nutrient Management in Wastewater Treatment Plants: A Model-based Analysis

Source Separation of Urine as an Alternative Solution to Nutrient Management in Wastewater Treatment Plants: A Model-based Analysis

高速道路サービスエリアの水回り改善による環境負荷削減

In this study, the reduction on the environmental load by the replacement of conventional toilets with low environmental load toilets at highway service areas in Japan was quantified and a cost-benefit analysis concerning introducing low environmental load toilet such as waterless urinals and urine diversion toilets were performed. As for the results, the environmental loads from the service area, water consumption and energy consumption were reduced greatly by introducing low environmental load toilets. In addition, it is found that this system can be easily paid back in 3 years regarding the burden of the energy and cost when it is introduced into large service areas where the wastewater is treated by the sewage system.

Innovative designs and approaches in sanitation when responding to challenging and complex humanitarian contexts in urban areas

As recent emergencies have shown, there are still significant challenges in the timely provision of safe sanitation in natural disasters or conflict situations. In urban emergencies or areas where it is impossible to dig simple pit latrines because of high water tables, hard rock, or lack of permission, it takes agencies considerable time to construct elevated latrines or alternative designs such as urine diversion toilets. This paper describes the challenges often faced in the rapid construction of latrines in emergencies and then looks at a number of case studies, from the Haiti earthquake and the 2010 floods in the Philippines, of how these obstacles were overcome. It also documents some of the recent innovations and improvements suppliers have made in increasing the scope of their emergency sanitation equipment.

Source Separation and Treatment of Anthropogenic Urine

Anthropogenic urine, although only 1% of domestic wastewater flow, is responsible for 50–80% of the nutrients and a substantial portion of the pharmaceuticals and hormones present in the influent to wastewater treatment plants. Source separation and treatment of urine enables recovery of nitrogen and phosphorus, thus largely minimizing the energy requirements for nutrient removal at wastewater treatment plants, allowing for capture and reuse of nutrients, and creating a more efficient means for removal of pharmaceuticals and hormones. The goal of this research was to investigate the global status of urine source separation and treatment technologies and to advise a path forward for further research.Results from the literature review validate urine source separation as a means to recover nutrients, conserve water, and decrease overall energy requirements for both nutrient and micropollutant removal as compared to conventional wastewater treatment. Research has matured beyond the laboratory scale to include pilot projects in office buildings, private homes, and schools. Continued research is necessary to create marketable products, to develop life cycle and/or cost-benefit analysis, to determine social acceptance in the U.S. as most surveys and projects have been conducted in Europe, and to assess the most appropriate means and setting for urine treatment.This title belongs to WERF Research Report Series.ISBN: 9781780400051 (eBook)