Three years of operation of the urine diversion system at GTZ headquarters in Germany: user opinions and maintenance challenges

Abstract

In the main office building of GTZ in Eschborn, Germany a resource-oriented sanitation system containing urine diversion (UD) toilets and waterless urinals has been in operation since 2006. After 2.5 years of operating the system, a first overall evaluation of the system in terms of its acceptance amongst the users and the cleaning staff was conducted by carrying out two surveys and many interviews. The overall result is that most of the users appreciate the sanitation concept in theory but have problems with the technical design of the particular type of UD flush toilets installed here. The survey results also gave some directions towards which hygiene devices the users would appreciate in order to overcome their reluctance to sit down on the toilet seat in public buildings (the sitting being necessary for correct operation of the urine valve to separate urine from flush water). Also, it is difficult to convince the cleaning and facility maintenance staff of the necessity of special cleaning and preventative maintenance routines. Hence, before such systems can be widely used, clear cleaning routines and maintenance instruction are required as well as certain technical modifications of this type of UD flush toilets to optimise the urine/water separation and the flushing properties of the toilet.

Characterization of urea hydrolysis in fresh human urine and inhibition by chemical addition

“…4,5,9 The precipitates that form are hard minerals that are not easily removed. 18,19 This results in frequent and expensive cleaning and maintenance. The ammonia produced also causes strong odors to persist in restrooms and storage tanks.…”

Thermodynamics of hydrogen production from urea by steam reforming with and without in situ carbon dioxide sorption

“…Other than water, urea is the main component of urine, where it is found in average of 2 wt%, depending on protein diet. Urine can be separated from human waste using urine diversion ('UD') toilets or 'waterless' urinals, and has great potential as a natural fertiliser [13,14]. The presence of urine in wastewater requires expensive retrofitting wastewater treatment plants with a de-nitrification stage to prevent the pollution of nearby waterways and coastline.…”

Struvite Recovery From Source-Separated Urine Utilizing Fluidized Bed Technology

“…Percentage of pharmaceutical degradation can be seen in Table 3. Treatment of source-separated urine is being conducted in Germany, Australia, Austria, and Switzerland, Sweden and in third world countries on a small-scale basis (Blume andWinker 2011, Fewless et al 2011). Source-separated urine can undergo various methods of treatment depending on the intended end product.…”