Cathy Ryan

Passive evaporation of source-separated urine from dry toilets: prototype design and field testing using municipal water

Published by Journal of Water Sanitation and Hygiene for Development

2015 A prototype urine evaporation unit (UEU) that removes water from human urine produced from a urine-diverting dry toilet using passive solar evaporation was designed and field-tested at a meteorological station. Municipal water was evaporated on vertically stacked plastic cafeteria-style trays that create a large evaporation surface with a small land-area footprint. The trays were located inside a Plexiglas® enclosure exposed to UV light while passively heating the UEU like a solar oven. A metal black chimney also heated up ...

URL: http://washdev.iwaponline.com/content/5/3/392.abstract

Passive evaporation of source-separated urine from dry toilets: UES optimization and dry product accumulation over time

Published by Journal of Water Sanitation and Hygiene for Development

2016 A urine evaporation system (UES) was optimized and evaluated in a laboratory by adding 5 L of urine at the same time each day for 65 days. The UES consisted of a wooden box that is open at the front only with tracks for 22 vertically stacked cafeteria-type trays and a fan and chimney at the back. Urine flowed from tray to tray via gravity exiting each tray via a weir along the long side of the tray. A distinctive physical and chemical zonation in the solid urine product was observed from the upper to lower trays due to leaching of ...

URL: http://washdev.iwaponline.com/content/6/1/96.abstract

Dissolved gas ‘concentrations’ or ‘concentration estimates’e A comment on “Origin, distribution and hydrogeochemical controls on methane occurrences in shallow aquifers, southwestern Ontario, Canada”

Published by Applied Geochemistry

2015 The need for research into the occurrence, origin, and fate of groundwater gases is reflected in an almost exponential increase in peer-reviewed publications involving dissolved groundwater gases. We enthusiastically endorse all efforts to develop baseline inventory of groundwater methane concentrations, and other markers, prior to exploitation of unconventional gas sources, as McIntosh et al.(2014) have done. In our view, however, the lack of verified, standard approaches for the combined sampling, storage, manipulation, ...

URL: http://geofirma.com/wp-content/uploads/2015/09/ryan-et-al-2015-sampling-dissolved-gas-in-domestic-wells_creativeCommons.pdf

Controls on nitrate loading and implications for BMPs under intensive potato production systems in Prince Edward Island, Canada

Published by Groundwater Monitoring and Remediation

2015 Potato production is critical to economy of Prince Edward Island (PEI), but has been linked to increasing groundwater nitrate contamination and anoxic events in estuaries. Given that PEI is entirely groundwater-dependent for potable water, this has resulted in considerable pressure to find solutions to protect water quality. However, our understanding of the controls on nitrate loading to groundwater, and the consequent potential to mitigate nitrate loading through beneficial management practices (BMPs), is limited. In PEI, flow ...

URL: https://scholar.google.ca/citations?view_op=view_citation&hl=en&user=OBpifQYAAAAJ&sortby=pubdate&citation_for_view=OBpifQYAAAAJ:HtEfBTGE9r8C

Can CO2 trigger a thermal geyser eruption?

Published by Geology

2016 Geyser eruptions are produced by a complex and poorly understood set of subsurface processes and conditions. They typically have an abundant supply of water, relatively permeable and competent subsurface material, a conduit to the surface, a driving mechanism (commonly believed to be the initiation of gas lift pumping by steam formation in the conduit), and a trigger. Here we present time series of dissolved CO 2 concentrations in near-surface discharge waters of a thermal geyser in Yellowstone National Park ...

URL: http://geology.gsapubs.org/content/44/4/307.short