Questions tagged [water-treatment]

Questions about any process which makes water more acceptable for an end use.

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5answers
81k views

Does water really 'go bad' after a couple of days?

Among my friends it is a sort of 'common wisdom' that you should throw away water after a couple of days if it was taken from the tap and stored in a bottle outside the fridge, because it has 'gone ...
40
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5answers
42k views

Is it safe to drink reboiled water?

There have been some claims saying that drinking reboiled water is dangerous because it produces arsenic, nitrates, etc. Is this true?
17
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2answers
5k views

Not your ordinary hard water deposit

We have a well that delivers hard water and we do not have a water softener. (There was a “green sand filter” that utilizes permanganate to oxidize other metals on the system, but it has been ...
16
votes
2answers
60k views

EZ-Water - Fraud or breakthrough?

Recently the quack medicine folks online have been promoting the research of a certain Dr. Gerald Pollack who claims to have discovered a "forth phase of water", and who has recently published a book ...
16
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2answers
274 views

What are the mechanisms for capture of As(III) and As(V) by magnetite from water?

Magnetite, $\ce{Fe3O4}$ is able to capture $\ce{As(III)}$ and $\ce{As(V)}$ from drinking water through the following mechanisms. Bidentate-binuclear complex Monodentate-binuclear complex (both from ...
11
votes
2answers
40k views

What chemicals are in tap water that gives it a slightly basic pH level

In chemistry, we recently did a lab where we observed the different ways of reading pH of several different substances. We used things such as red cabbage juice, litmus paper, pH paper and a pH probe. ...
10
votes
1answer
898 views

Isolating salt from sea water using filters

Could a filter be used to isolate salt from sea water? Could we say that the water molecules are smaller than the molecules of salt dissolved in the water. I have no relation to chemistry or physics, ...
8
votes
1answer
309 views

When and how in anaerobic digestion is water dissociated?

Anaerobic digestion and methanisation of organic feedstocks is a complex series of processes that result in biogas. One way to look at this is a very top-down, stochiometric approach as in the Buswell ...
5
votes
1answer
2k views

How much ascorbate to neutralize one liter of chlorinated tap water?

In Las Palmas de Gran Canaria, tap water is chlorinated. In an Internet forum, someone claims that in 2008 the water had a chlorine concentration of 0,5 - 1mg/l. On the official site of Emalsa, the ...
5
votes
1answer
282 views

Can iodine be used to disinfect water?

I think it was Nat Geo.. Not sure exactly.. Where I heard, years ago, that a drop of iodine can be used to disinfect water of say, 1 litre. But isn't chlorine used to kill all bacteria? I mean I don'...
5
votes
3answers
827 views

Is there a household method to decolorize potentially contaminated water?

I am living in my dorms at the moment and apparently it is an accepted thing that the water in the building is brown and yellow. According to my RA, this is a characteristic of the town I live in. ...
4
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2answers
638 views

Does adding slices of lemons to water reduce its chlorine content?

Often restaurants add slices of lemon to water. They seem to make the water taste better and perhaps reduce or at least cover up the chlorine taste. I've heard that Vitamin C tablets can be used to ...
4
votes
1answer
274 views

Can Aquatabs be used to clean swimming pool water?

Can Aquatabs be used to prepare/chlorinate water for swimming? They are used to clean water for drinking so is it safe to assume that if used in proper quantity they can also clean water for ...
4
votes
1answer
554 views

How does chlorine in water evaporate?

Drinking water (e.g. from your home's tap) is spiked with chlorine, for an amount of just some ppm. Purpose of this operation is to kill bacteria, for our health. Background: chlorine in water is ...
4
votes
1answer
2k views

What can cause artesian well water to smell?

Recently, our water from the artesian well started to smell (again). It only smells bad for only few seconds than the smell disappear. We have sulfur-iron removal system, water softener, UV lamp. ...
4
votes
1answer
2k views

Do minerals and/or metals found in water tend to settle to the bottom?

I was reading an article that suggested that if one lets water sit for a day in a bottle or pot, then some of the metals in the water, such as lead, will settle to the bottom. Does anyone know if ...
4
votes
1answer
355 views

What does ozone smell when treating with household water?

We live in a rural area and our well water comes from storage tanks that are continously being ozonated before passing through an infra red lamp. The water in the house smells like it contains ...
4
votes
1answer
166 views

Boiling aluminum in high-alkalinity water

This question ultimately relates to brewing beer, but more specifically to water treatment before brewing. Though I can't get a water quality report, I suspect I have high levels of bicarbonate ...
4
votes
1answer
239 views

Do I really need 4 different water treatment systems with this water analysis?

We installed an artesian well and we had some surprises. We asked a few places around and they all told me that we needed 4 different systems to solve our water problem. I am ready to accept this fact ...
4
votes
1answer
162 views

Is there a chemical treatment for pipes to reduce or eliminate leaching of lead into tap water?

Given events in Flint, Michigan, where a switch to acidic river water in the city water supply resulted in leaching of lead into tap water from the insides of pipes, I wonder -- has anyone has heard ...
4
votes
1answer
186 views

Does oxygenating tap water remove the tap water flavor?

I know flavor is subjective and not exactly quantifiable, but I think there's merit to this question. We've all experienced that tap water often tastes a lot worse than bottled water or filtered ...
4
votes
1answer
208 views

What is this device? (Constant level device?)

Found this in my lab on a random shelf (water quality lab). It is old enough that nobody knows where it came from. I think it's a constant level device. It has in- and out-flow connections, as well as ...
4
votes
0answers
437 views

The Health Effects of Alkaline Ionized Water?

I came across alkaline ionized water as my aunts bought a system called Kangen Water from Enagic Inc. The water produced by this system is claimed to contain smaller water clusters (4-6 molecules) ...
3
votes
2answers
921 views

What is hard and soft water and how does the process of dissolution work?

This is a very basic question about solubility, especially solution of table salt in water and solution of sugar in water. I have heard about terms like hard water, soft water, filtering of water to ...
3
votes
1answer
165 views

Quality of water for drinking purposes

As I’m reading about water cations and anions, I read that the benefits we gain from water are of course lots, but the most important of them is the neutralisation of acids ($\ce{H+}$) from the anions ...
3
votes
0answers
229 views

Cheap spectral analysis to analyze water quality

I need some guide about spectrometers I saw a lot of DIY spectrometers to analyze light. Does anyone try to use those DIY spectrometers to analyze water? To detect heavy metals? or a chemical? or ...
2
votes
2answers
854 views

Is there a treatment for distilled water become drinkable? [closed]

It is my understanding that, drinking distilled water may not be recommended. Its not recommended indeed. Or maybe its not not recommended... Maybe not not indeed........ Anyway.... Well, apparently, ...
2
votes
2answers
417 views

Are non-ionic compounds generally as dehydrating as ionic compounds in drinking water?

In order to turn sea water into drinkable water, virtually all of the salt must be removed. By definition, salts are ionic compounds. I am assuming that there are other non-ionic compounds devolved ...
2
votes
1answer
839 views

What are the methods of fluoride removal from drinking water?

I would like to remove fluoride from my water supply. Are there any methods, any test kits or water distillation units to remove fluoride from drinking water? See also: Is there any at home test ...
2
votes
1answer
3k views

Test for chlorine and chloramine in city water supply

I am looking to install a water filter system and I wanted to test the water for free and total chlorine. I understand from the city water report that it uses chloramine and NO chlorine (test report)...
2
votes
1answer
889 views

Zeolite process

I'm a higher secondary school studet. See this following image, I can't understand how water can rises through the bed of permutit, my textbook says - Hard water introduced from the top of tank and ...
2
votes
1answer
732 views

How does water deionization process work?

What are the technical/scientific details behind the process of water deionization? How does deionization machines like those manufactured by Millipore work?
2
votes
1answer
135 views

What happens with ammonia ions in tap water after they are separated from chlorine?

Tap water is increasingly treated with chloramine which is composition of chlorine and ammonia. Chlorine can be removed by catalytic activated carbon and ammonia ions are then left. What happens with ...
2
votes
1answer
91 views

Determining the amount of water to create a given pressure in a sealed container

I have a sealed container with a volume of 1 liter. I want to go from an initial pressure of $P_{1}=1\ \mathrm{atm}$ and an initial temperature of $T_{1}=298\ \mathrm{K}$ to a final pressure of $P_{2}=...
2
votes
0answers
51 views

Creating Floc in the classroom

I'm the youth ed manager at Denver Water in Colorado. We do a water treatment demo in the classroom, and currently we use the first part of the Winkler DO test to create floc. I'm looking for a better ...
2
votes
1answer
78 views

What are the ways to make radioactive water drinkable again? [closed]

Let's say survivors in the area contaminated by radioactive fallout need to somehow process the water from rivers, rain or pipes. How could they go about it? Is it even possible to 'remove ...
1
vote
2answers
81 views

Why we don't we save water by boiling the contaminated water to get the pure steam?

I see lot of drinkable water wasted in household and industrial activities, water usually gets contaminated with detergents(and other household materials),chemical effluents released from factories . ...
1
vote
2answers
431 views

Water cooling by evaporation

For many years of drinking water has been cooled in hot climates by evaporating it from the surfaces of canvas bags or porous clay pots. How many grams of water can be cooled from $\pu{35 ^\circ C}$ ...
1
vote
2answers
86 views

Waste water treatment [closed]

This is a very simple question: Why are oxidized compounds generally thought to be less toxic/polluting than reduced species? This is used in waste water treatment where oxidizing agents (such as ...
1
vote
3answers
4k views

Filtration methods at removing ions present in water

I'm doing a lab where I have to first find out what ions are present in the water (easy part). The next part is to filter out those ions from the water. Here are some methods that are stated on the ...
1
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1answer
2k views

What are the effects of storing drinking water in a copper container?

I recently learned that Ayurveda recommends storing drinking water in copper containers for positive health benefits. Upon my simple experimentation, I've noticed the following effects: Water Type :...
1
vote
1answer
12k views

Can water electrolysis detect the water impurities?

A salesman came to my house to demonstrate his water purifier machine which is a RO Purifier. To show the difference between his purifier machine and the machine I own, he took some water from my ...
1
vote
1answer
45 views

Biological contamination from ground

I took samples of tapwater in order to examine concentrations of Escherichia coli and enterococcus in a rural area. I was told, from an analytical lab, to take samples in four sterilized vessels ...
1
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1answer
281 views

DIY spectrometers limits as a water quality sensor

What pathogens or harmful stuff IN WATER can you detect with these homemade video spectrometers (webcam) + UV light? https://www.youtube.com/watch?v=IA5BTD-aelo I'm trying to do a cheap spectral ...
1
vote
1answer
1k views

Can I add citric acid to KCl for iron removal in a water softener?

I recently installed a water softener and having a fair amount of clear iron in our water, I've been using Morton Rust Remover pellets which are basically NaCl with citric acid added as an additive. ...
1
vote
1answer
5k views

Why does my filtered water turn thick and almost slimy when refrigerated?

I just started using a water filter. I have 2 containers to store the filtered water; one goes in the fridge and the other stays out on the filter. The water that stays out is fine and stays good ...
1
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2answers
84 views

Water purification procedure that does not involve a flocculant of any kind?

I have read about "electroflocculation" that uses less flocculant/alum, but is there a method – no matter how expensive or impractical – that uses no flocculant at all?
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0answers
28 views

Do TDS meters measure HCO₃⁻/CO₃²⁻?

I am trying to add $\pu{2 g}$ of $\ce{KHCO3}$ to $\pu{20 L}$ of RO water $(\mathrm{pH} = 5.2)$ which theoretically it will add $$ \begin{array}{lr} \hline \ce{K+} &\pu{10.32 ppm} \\ \ce{HCO3-} &...
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1answer
49 views

Making hard water

Does anyone know how to make hard water with a hardness of 200+ ppm in terms of $\ce{CaCO3}$? I live in Seattle and we have very soft water and we need hard water for testing purposes. Obviously you ...
1
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1answer
27 views

Is it stupid to put used acid into a pool after cleaning the chlorinator? [closed]

I have a salt pool, and when the chlorinator salts up with calcium, I clean it with a diluted acidic solution. What happens to the acidic solution after the reaction happens? I.e., does the pH change?...