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How to Clean Silt from Dug Round Water Wells Used by 3-4 Billion People on Planet?

This is a clam shell bucket, from an old toy crane. I am taking this to a machine shop, welder, had having them make it 18 inches wide. It would be used only with rope, no block and tackle.  Problem: As best I can surmise, about 1-10 percent of hand dug, round water wells used by around 4 billion people on the planet are full of silt, dirty, and old plastic jugs used to pull the water up from well. As the silt rises in the well, the wells slowly become too dirty, or the locals need to pull the water out in buckets, then allow the silt water to settle. It is way to expensive for people who earn 10 USD per day to pay people with pumps to drain the wells. I want to create a 1-2 man powered clamshell bucket system to clean these wells.  What is the best way to make a method to clean a dug well? How much would the steel, rebar cost? Labor is 10 dollars per day in central American, South America, Africa etc. Thanks for help, I will take the finished bucket to Lome, Togo West Africa to test, and modify, iterate. Andy Lee Graham of HoboTraveler.com https://www.hobotraveler.com/blogger.html

Topic by hobotraveler    |  last reply


How much water is in my cistern?

I built a 33 gallon cistern my garage to collect condensate from my HVAC system. (I didn't have room outside my condo for a rain barrel). It has a spigot and a short hose, it lives above my utility sink, which is where the overflow goes when the cistern is full. I'm hoping some clever makers can give me some ideas on how I can build something that will tell me how much water is in the cistern. I have Samsung SmartThings so I've considered putting a water sensor just below the overflow hole, so I will know when it's at 100%, but I would prefer to have a percentage reading and an alarm when it gets to 90% or so. I considered an arduino with an ultrasonic sensor but that a bit involved... Not opposed to it but please be prepared to hold my hand thru the process of you propose it! ☺. Non-SmartThings solutions also welcome.Thank you - looking forward to your genius ideas!!Mark

Topic by MarkB673    |  last reply


Greywater and rainwater?

Can I use rainwater with a greywater system with an underground cistern?

Question by Yetigonawry    |  last reply


12 Hurricane Preparedness Projects

I read some of the 12 projects. I did one myself since I live in Puerto Rico, went through Hurricane Irma this past Wednesday (Sept 6th) ,have been though several hurricane sin the past (since 1964), and will go through a new one (Hurricane Jose) this weekend. In most occasions, we lost power and water for days. I lost only power for 30 hours after Hurricane Irma. My own project was a two part installation for when I lacked water (I have a generator set for power): 1. Install a 50 gallon cistern on my roof to store potable water for cleaning and bathing needs 2. Install a pressurized 20 gallon tank for showering The 50 gallon cistern was actually a large trash barrel with a removable cover ($40), which I added two 1/2 inch plastic faucet valves, one near the base as a gravity fed output, and one on the cover as a water inlet. After cleaning the barrel, and attaching the valves, I fixed the barrel (now a "cistern") on my roof (over a beam for weight distribution) with two wire guides. I attached a plain water hose from an external faucet to the top valve to fill the cistern. Then I attached a new hose to the bottom valve and ended that with a regular sprayer. I fitted this into the bathroom over the toilet tank and near the sink, so it can be used for face and hand washing, and for filling the toilet tank after each flush. The pressurized water tank is a unused water heater that can hold up to 120 PSI. I replaced the cold water inlet with a cap and a auto tire valve by drilling into the cap and pulling the tire vale through (same as for a wheel hub).. I installed a 1/2 inch faucet on the hot water outlet and a short (pressure resistant) water hose, and finished it with a water sprinkler. Then I installed a.new 1/2 inch valve on the drain.for the lower water inlet.  I attached the hose from the cistern to the lower valve, opened the valves on the cistern output and tank input, and removed the inner stem from the tire vale. When the tank was full, some water will spurt out from the open tire valve. Then I close both valves, remove the cistern hose, reinstall the tire valve stem, and use an electric air pump to apply pressure up to 50 PSI.  Now if I open the water sprinkler, i have a hand held shower!  After one use (about five minutes) the pressure can drop but if I have electrical power, I can reapply air pressure again. After several showers, I release the remaining air pressure at the tire valve, refill the tank from the cistern, and apply air pressure again. This has worked for years, and I keep everything ready for the next storm of when I have no water supply.

Topic by RaymondR6    |  last reply


How to build a water storage tank that will keep still water from freezing? Answered

How much insulation would be needed and and how would you build it? It has to be outside and be able to supply enough water for a family for a few days. Any ideas?

Question by blkhawk    |  last reply


Technology Makes Cheap Drinking Water from Air

INTRODUCTION:   How can we best apply basic technology to help the underprivileged and/or disaster-hit countries like Haiti? Daily hygiene and nourishment are among the top needs for disaster ridden regions!  Simply put, no water means no hygiene. The Romans understood that over two millennia ago and created their complexly beautiful aqueduct networks for handling both fresh and wastewater! Other ingenious water systems like “air wells” have been found in the city of Theodosia (cf: discovered in 1900 by Zibold, see Zibold’s Collectors/Dehumidifiers) dating back to Greco-Roman times during the Byzantine Empire. These were strictly passive systems that naturally dehumidified air, collecting its potable water in underground basins. All air, even in relatively dry desert regions, will precipitate or release its natural water content (initially in the form of vapor) through condensation when it hits its dew-point temperature and below. That means you “chill” it to an appropriate level that is anywhere from 5F to 50F below its current air temperature, depending upon how much water content (relative humidity) it has locally absorbed. The condensation of the water vapor releases its internal latent heat (reheating the cooled air) which must be constantly dissipated (absorbed by something) in order for water formation to steadily continue. So how do we dissipate this resultant vapor-heat and chill our air without any infrastructure or electricity, in an underprivileged or disaster-ridden region? We simply bury a long cast-iron or any metallic drain-pipe sufficiently underground where the temperature of the earth is naturally held to a constant at around 45F to 55F. That’s our “free” chiller gift from nature. One end of the pipe, Figure-1,  sticks out of the ground to suck-in local outside hot air, and the other end dumps cooled dry air and water into an underground cistern where it gets collected and is piped to the surface to both exhaust the cooled dry air and connect to a water pump. We need a hand operated water pump to lift up the water above ground, and we need an electric fan to constantly pump air through the ground-chilled piping system. We can even force the cooled piped air to exhaust into a tent-like structure where it provides air conditioning as an added bonus, but this adds the penalty of both power and the increased fan size necessary to drive our required airflow further into an enclosure! While this concept is not “passive” (requiring electricity to work) like those clever Byzantine air-wells, it will produce much more potable water and within a smaller volume than those elegantly passive historic devices. The electricity for our fan power requirements can be produced by any one of four ways using either “active” or “passive” techniques: 1) An active playground or bike-pedaling-person or oxen-driven mechanism-generator, 2) A passive windmill generator, 3) A passive solar energy collection system that directly generates electricity, or 4) A passive thermo-electric system that directly generates electricity using the Peltier effect, operating solely on temperature differences between the cell’s top and bottom surface (we jury-rig the cool pipe and hot ambient air to contact separate sides of the cell). Depending upon how much water is needed, the required air volume plus pipe length and diameter, together with the fan will be sized accordingly. We can also configure groups of parallel fan-driven air pipes that are radially fed into the cistern. The sizing of this underground network depends upon the ambient air’s local average temperature and relative humidity (how much water gets absorbed into the air) plus buried pipe depth and effective underground temperatures achieved. The basic concept is one where we “wring” water from air at some given humidity content. The higher its relative humidity the more water is recovered from the air. The air-wringing process simply chills the air as it scrubs along the cooled internal pipe surface until it starts to rain inside the pipe from condensation onto its surface. The condensation is like the dew that forms on car windows, grass or any cooled surface in the early morning, before the sun comes out and evaporates the dew back into the heating air. A further bonus is that our dew-formed water is naturally distilled and very clean. It is potable water ready to drink without the need for additional sterilizing agents. Of course, we must make sure that the interior piping and cistern network is biologically cleansed before burying it underground. The hand pump with its 10 to 15 foot extended piping to reach the underground cistern must also be cleansed. The beauty of this constantly replenishable water supply is its convenient underground installation anywhere! After the in-ground installation, we have a virtual, partially passive, no moving parts, non-breakdown system containing above ground total access to all moving parts that could breakdown, namely the water pump and electric fan. Also, it is easily maintained, with few moving parts (water hand-pump and electric fan) and basically lacking any technical complexity which makes it ideal for technologically backward regions. The example below uses a relatively small industrial fan moving air at 1500 CFM (Cubic Feet per Minute) with a DC motor rated at 1kW. This fan together with our underground piping system will conservatively generate 12 GPH (Gallons Per Hour) of potable drinking water without need for any purification chemistry. Based on an average electrical cost of 14-cents per kWh (kilo-Watt hour), the typical commercial distillation of one gallon of drinking water costs roughly 35-cents as compared to our cost of only 1.2-cents. Furthermore, if we decide to go green and use solar energy for generating our water, it would effectively cost us nothing beyond the initial installation! USING A PSYCHROMETRIC CHART TO SIZE OUR WATER SUPPLY: The following gets a little technical and is only provided for those die-hards who are truly interested in how the science works. Those non-technically schooled may skip this part and not miss the basic concept. Figure-2 shows a Psychrometric Chart for air. This chart summarizes some of the basic thermodynamic properties of air throughout its typical range of operating temperature. The chart uses six basic air properties that defines the physical chemistry of water evaporation into air:  (1) the enthalpy or total energy contained within a unit of air which is a combination of its internal and external energy, expressed as the amount of BTU-energy per unit mass of reference dry-air, (2) the specific volume or the ratio of a unit volume of local air to its mass of reference dry-air, (3) the humidity ratio or the amount (mass) of moisture in a local unit of air divided by its reference mass of dry-air, (4) the percent relative humidity per unit of local air, or the mass ratio (expressed in percentage form) of the partial pressure of water vapor in the air-water mixture to the saturated vapor pressure of water at those conditions (the relative humidity depends not only on air temperature but also on the pressure of the system of interest),  (5) the dry-bulb temperature or the locally measured air temperature, and (6) the wet-bulb temperature or saturation temperature which is the local air temperature experienced during constant water evaporation (a wet-bulb thermometer is typically used:   a thermometer that measures resultant temperature while wrapped in a water wet-gauze and spun to generate local air movement and max-evaporation)  1.0   The Process and A Sample Calculation Our Psychrometric Chart uses six thermodynamic properties that help to determine the amount of water available for extraction from the local ambient air as a function of its temperature, pressure and relative humidity.  Let’s assume the following local ambient conditions for the region we plan to construct our water system at:  (1) Typical daily air temperature Td = 106F and one atmosphere pressure assumed at sea-level, (2) Relative Humidity, RH = 55%, and (3) Typical underground temperature down at six feet is measured at Tu=55F (at 12ft. it drops to ~45F). This yields the following calculated results for obtaining a steady-state supply (changes at night) of water to fill the cistern:      1)      In our example, the “local” air (dry-bulb) temperature is Td=106F, at a relative humidity of RH= 55%.  Fig-2 indicates that the resultant Humidity Ratio is HR= 0.0253 Lbs-water/Lb-Dry-Air (intersection of Td=106F line and RH=55% line, then horizontal to HR value).  We then determine the “gulp” of air volume containing the HR Lbs-water which corresponds to the point of intersection of Td and RH. Interpolating on specific volume “mv” yields mv=14.7 ft3/Lb-Dry-Air (this value sets the optimum unit airflow for our given ambient conditions, and creates a ballpark pipe length to diameter ratio needed later). It represents the basic unit of air volume that will enter our underground pipe per given time, and ultimately defines the size of our fan and piping network. For increased water creation, multiples of this unit volume will scale up the additional amounts of water that can be collected. 2)      As the inlet air cools down to a temperature of Tu=55F, from contact with the relatively cold underground pipe, we follow the constant enthalpy line (red upward left-diagonal) from the intersection of Td and RH to its saturated air temperature condition of Ts= ~88F, which is its dew-point temperature where the corresponding local RH=100%.  At this temperature or under, the air precipitates and releases its moisture content, resulting in water condensation onto the pipe walls.  Since our air will chill to a final pipe temperature of Tu=~55F, we follow the RH=100% saturated curve (green) down to yield an HR=~0.009 Lbs-water/Lb-Dry-Air. This is how much water is left in the air when it gets to 55F.  Therefore for every pound of local outside air that enters the pipe, mw=0.0253 – 0.009 = 0.0163 pounds of absolute pure, distilled potable water precipitates onto the inside pipe wall (per pound of dry air that is cooled and dehydrated) to gravity-flow out the pipe exit and into the cistern. 3)      We now convert pounds of air per unit time into a unitized volumetric airflow that yields gallons of hygienically pure potable water production per unit time. For every Va=100 ft3 of local volumetric air movement per minute (CFM) through the pipe, which translates into ma=Va/mv= 100/14.7 = 6.8 lbs. of dry air per minute or 6.8 * 60 = 408 lbs. per hour (PPH), to yield a water-flow of mwf=ma * mw = 408 * 0.0163 = 6.65 PPH or 6.65/8.345 = 0.8 GPH of water.  An industrial fan rated at 1kW DC will typically move 1500 CFM at a pressure of 8-iwc, to continuously produce 15 * 0.8 = 12 GPH of pristine potable water. 4)      Not shown here are the design details of sizing our pipe, fan and solar collection system for electric power requirements using heat transfer principles coupled with a thermodynamic heat balance, and aerodynamic fan performance assessment. These details help to size the electric power generation requirements plus margin used to properly size a solar collector containing further margins for overcast days. The engineering involved here is straight forward but beyond the scope of the current project.

Topic by RT-101    |  last reply