Our paper “Models for predicting organic micropollutant breakthrough in carbon adsorbers based on water quality, adsorbate properties, and rapid small-scale column tests” received favorable reviews. It appears that the revised manuscript based on suggestions by the editor and reviewers will be accepted soon. When and if that happens I’ll write a redux for it like I did for the previous paper. Hopefully it will also be available open access for a period of time following online publication; if so I will send out the link for you to access.
Work on the next paper - which I believe will be the last in the sequence needed to connect the adsorption research base to the kit of practical design tools we’re building for practitioners - has begun. The modeling and statistical work is on-hold at the moment though. That task is beyond my expertise and my colleague who usually does this work has his hands full with childcare, teaching, and other obligations. While he is taking care of those important items I’ve started to work ahead on book sections.
Book sections coming down the road include overviews of treatment steps that come before or after biochar adsorption to address other water quality parameters. These include removal of turbidity (sediment and particulates); removal, destruction, or inactivation (prevented reproduction) of biological pathogens; and control of water taste, odor, and appearance issues.
We have provided basic instructions and design specifications for constructing low-cost multi-barrier water treatment systems in the form of open access graphical manuals available from Aqueous Solutions. The smaller of these is the 300 liter-per-day so-called “blue barrel” system pictured here:
In the two manuals available - the 300 L/d blue barrel system and a larger 2,000 L/d system made using concrete tanks - we use minimal text for explaining the function of each step and key details for operation and maintenance. The manuals are step-by-step instructions for building these specific systems. The objective of forthcoming book sections is to explain key engineering design criteria and specifications for practitioners to be able to adapt treatment systems to a wide variety of applications, rather than just choosing one or the other systems detailed in the manuals in a “paint-by-number” approach.
As a first installment I’ve put together a section on biological slow-sand filtration (BSSF) for control of microbial pathogens (step 2 in the illustration above) for paying subscribers. It provides an overview of the mechanisms of treatment at work in BSSF, and provides ranges for design and operation specifications for BSSF units based on “engineering textbook” recommendations as well as our accumulated “horse sense” born of practical experience setting up BSSF units in low-resource settings. It also includes a bibliography with links for further reading on roughing filters, rapid and slow sand filters, and biodegradation of chemical contaminants in sand- and carbon- based biofilters.
These are all big topics with robust subdomains of the technical literature. One challenge for me will be defining what of this is in-scope versus out-of-scope for the book project.
FYI if I had to pick one single go-to practical all-around source on the topic, it would be Joy Barrett’s 1991 Manual of Design for Slow Sand Filtration (free download!).
Hope you enjoy the coming posts, and please do keep the feedback rolling in!
I think that it have some problems with the pre-filter. The water will go up without pass the pre-filter to the top it will go up via middle tube
Hello, can you tell me if it is necessary to have all four sections of the barrels if you are working with deep groundwater from a well (51 meters deep) that is supplying very clear water.? Even though it is clear, I would not assume it is free of contaminants. This is surrounded by Isan Thailand Farms where there is copious use of pesticides. Thank you for any advice. Best..