Urine Diverting Toilets in Climates with Cold Winters
There was post on the yahoo group ECOSANRES asking about Cold Climate toilets -Cold weather toilets.
A reply mentioned this PDF:
Urine Diverting Toilets in Climates with Cold Winters Technical considerations and the reuse of nutrients with a focus on legal and hygienic aspects.
While the report is several year old, the $h1t is still good and worthy of summarizing
Authors and Editors:
- Anna Richert Stintzing
- VERNA, Ecological Inc., Sweden
- Dr. Håkan Jönsson
- Dr. Caroline Schönning
- Kati Hinkkanen
- Dr. Elisabeth Kvarnström
- Dr. Zsofia Ganrot
- Margriet Samwel
- Sascha Gabizon
- Annemarie Mohr
- Publisher: WECF – Women in Europe for a Common Future
- Pages:42 1.35 mb
- It is formatted 3 columns / page which doe not lend itself well to computer screens and pdf readers
- It is a fast read to those in this field
- It is a good read for someone who knows little about this field
1 – Summary
2 – Dry Urine Diversion
3 – EU directives relating to dry urine diversion where urine and faeces
4 – Legal aspects
5 – Cold temperature aspects
– Freezing of urine
– Hygiene and treatment of urine
– Pharmaceuticals and hormones
– Hygiene and treatment of faeces
– Technical aspects: construction and maintenance of
– urine diverting toilets in climates with cold winters
– Pipes for urine
– Odour control with ventilation
– System for reuse of urine and faeces in crop production
– Home gardens
– Large Scale Agricultural Production
6 – Examples from pilot projects and research from the northern hemisphere
7 – Knowledge gaps and identified research needs
8 – Annex
Three key points from the Reportssummary are:
“There are functioning examples of dry urine diversion in regions in the world with cold winter climates. The examples presented in the report show that it is possible to arrange agricultural reuse of urine and faeces in large or small scale crop production.”
“The fact that there are only short periods during the year when urine can be used as a fertiliser place demands on a storage system for the urine. There are a few alternatives; one of the most economic may be to arrange storage on a farm, in covered storage containers previously used for animal urine.”
“There are still development needs and knowledge gaps. Some of these are related to temperate and cold climates, such as the fate of microorganisms in urine at temperatures below freezing. However, this should not be considered a major constraint to the development of dry urine diversion, since the risk is relatively low, and can be handled through combination with other hygienic activities.”
The report reprints 3 basic but useful tables from other organizations:
1: Recommended guideline storage times for urinea based on estimated pathogen contentb and recommended crop for larger systemsc (WHO, 2006).
2: Requirements on storage and allowed crops for diverted human urine that is collected from larger systems. (Swedish EPA, 2002).
3: Recommendations for storage treatment of dry excreta and faecal sludge before use at household and large-scale (municipal) levels. The treatments assume no
addition of non-sanitised material (WHO, 2006).
Again the report is a quick and easy read, providing a good preface to a much larger document that needs to be written on the subject. The report ends nicely, saying we need more research :
“There are some definite areas where there is a need of systematic research and development (R&D). Some of these, especially related to winter climate aspects, are specified in the following text.
One of the most discussed questions regarding urine diversion is the fate of pharmaceutical residues after excretion, and how this affects choice of collection and treatment of human excreta. Research on fate of pharmaceuticals in waste water treatment plants is being undertaken in Germany and Sweden. No known field studies are taking place on fate of pharmaceutical residues when urine or sewage sludge is applied to the soil. The current recommendation to use urine as a fertiliser in agriculture rests on the analysis that the soil system is well suited to digest harmful organic substances due to microbial life in the surface layers of soil. This would be an interesting field of study that can give valuable information on design of reuse systems.
Sanitisation of faeces is another aspect that needs attention. The WHO guidelines on the reuse of human excreta in agriculture mention the alkaline treatment by adding ashes or alkaline substances with a storage time of 6 month ( > 35 °C ) as a possible way to sanitise faeces, or 1,5 – 2 years storage time. The temperature intervals given do not cater for needs in temperate or cold climates, which means that knowledge on treatment of faeces in this region should be developed. Research on more simple and robust treatment methods is needed.
Suggested applied R&D projects
– Establishment of new pilot projects and evaluation of existing projects. Monitoring and evaluation of existing dry urine diversion projects is a costefficient way of generating knowledge. Dissemination of results, regardless of if they are positive or negative, from existing pilots is vital. The establishment of new pilot projects will also contribute to the bank of knowledge.
– Sanitisation of faecal fraction: research on requested storage in ambient or alkaline environment in temperate and cold climates (winters with temperatures far below zero).
– Sanitisation of faecal fraction: research on the implementation of chemical sanitisation of faeces with urea. This is an interesting method, but the practical implications need to be studied and developed.
– Sanitisation of urine: what happens in the urine when it is frozen and what are the implications for storage intervals?
– Pharmaceutical residues: studies of soil system when urine is used as a fertiliser. Effect on microbial community, speed of decomposition. Comparisons with sewage sludge, farmyard manure.
– Toilet design: development of risers and squat-plates for local production. Care given to needs of different users: children, disabled, elderly, men, women. Toilets of today need development since many do not divert as much urine as possible, and are unnecessarily difficult to clean.
– Systems analysis from an economic point of view. Comparison of investment and maintenance costs of urine diversion systems and conventional sanitation.
– Systems analysis from an environmental point of view. How do different activities affect the sustainability of the system, for example fertilisation strategies, choice of tank, joint measures or single toilets?
– What are the economical incentives for implementation of urine diversion? How to design the economical system with the regard to municipal responsibility and financial support/ interactions. How should the systems be organized and which are the most important drivers for the different stake holders.”
other related links
- Inactivation of bacteria and viruses in human urine depending on temperature and dilution rate.
- The Swedish Eco-Sanitation Experience pdf
- Ecosan Sanitation Facilities resources
- Reuse of faeces and urine – Appropedia: The sustainability wiki
- Guidelines for the safe use of wastewater, excreta and greywater. Volume 1: Policy and regulatory aspects
- Guidelines for the safe use of wastewater, excreta and greywater. Volume 2: Wastewater use in agriculture
- Guidelines for the safe use of wastwater, excreta and greywater. Volume 3: Wastewater and excreta use in aquaculture
- Guidelines for the safe use of wastwater, excreta and greywater. Volume 4: Excreta and greywater use in agriculture
- Human urine – Chemical composition and fertilizer use efficiency