Consumable water

The only fully effective method of purifying drinking water

 

Allow me, in the proverbial ‘three words’, to recount the essence of drinking water throughout history and the current situation.

We all know from the first school textbooks that we used to drink surface water from rivers and lakes for centuries. Where there was no water on the surface, wells where groundwater was accumulated were reached. What was the purity of these waters? I would like to remind you that water, circulating constantly in nature, returned from the atmosphere in the form of rain, snow or hail, absolutely clean. It was only in contact with the soil or rocks that rainwater could become rich in certain minerals, the quantity and quality of which depended on the type of rock, the speed of water flow, its temperature, etc. I will mention at this point that there is no shortage of rocks on earth that are hardly soluble in water (granites, basalts, etc.), which causes groundwater or surface water to remain clean in such an environment, without the presence of minerals.

If over the centuries (I mean the period until the 19th century) we had any problems with water, then it was only bacteriological poisoning of the droppings from human communities. Over time, these problems have gained in importance, as the world’s population has grown, cities have become larger and wastewater has been flowing on the surface of the streets. The number of diseases and epidemics caused by bacteria and viruses from dirty water increased. Sewage water was very easily connected with drinking water. Ludwik Pasteur used to say that 90% of illnesses are drunk by people with water. A historic moment, therefore, was the introduction at the end of the 19th century of chlorine for disinfecting drinking water, which led to a decline in the number of diseases and epidemics. To this day, chlorine and its derivatives are still used in Poland to disinfect drinking water. As a component of water, it has never been free of defects, but only today it is heavily criticised, because the appearance of hundreds of new organic compounds in water gives rise to new compounds, often carcinogenic, in combination with chlorine.

But let us get to the heart of the matter. The rapid development of industry and new technologies, which has existed for over a century, results in the formation of huge amounts of new chemical compounds, which, along with waste and sewage, also enter surface waters, groundwater and even deep water. The situation in this respect has been very serious for years now and is becoming more and more dangerous every year.

The World Health Organisation (WHO) has calculated that as much waste in the form of rubbish, waste water and dust has been produced on earth over the last decade as it did over the past 70 years. At the same time, the WHO predicts that industry will generate the same amount of waste in the next five years.

In Poland, drinking water is drawn from various sources. About half of the population drink water of surface origin (most often from rivers), about half drink groundwater (i.e. from wells) and about 2% consume deep water (e.g. in Warsaw oligocenic waters). Recently, the number of consumed waters offered in shops has been growing, unfortunately, of different, not necessarily good quality.

What are polluted surface and well waters? Without going into details, we can make a simple division into two groups:

Mechanical impurities, i.e. water-insoluble suspensions such as sands, clays, humus, living and dead aquatic organisms. Therefore, these are elements that we can easily remove with different mechanical filters;
Bacteria and viruses – these are dealt with by chlorine and other oxidizers;
Chemicals that are estimated to amount to tens of thousands in our surface waters and groundwaters. For example, there are more than 100 PAHs in surface water, which are considered to be the most dangerous, and 80% of them are carcinogenic, and it is a tragedy that this water-soluble chemical cannot be removed in any traditional way. If we clean and treat drinking water in municipal plants, we will not remove chemical compounds in the process of sedimentation, nor will coagulation consisting in binding in gels the lighter mechanical parts in water using iron-aluminium sulphate, nor will gravel and sand mechanical filters and disinfection of water with chlorine or ozone give anything here. Waterworks do not remove chemicals from the water, on the contrary, they enrich it with iron-aluminium sulphate in the coagulation process and chlorine in the disinfection process. It is difficult for these institutions to blame for this situation. Their construction and technologies of water purification have not changed for 100 years, because nothing new has been invented in this area. But it has changed, and it is a drastic raw material that is being supplied to these plants. It will therefore come as no surprise to anyone that the Regulation of the Minister of Health and Social Welfare, which states that if surface water is to be processed and treated into drinking water, it must be water of the first class of purity. The problem is that there are no such waters in Poland anymore (in 1995 they accounted for 2.4%). Drinking water is now produced from water of class III of Part III of the Annex to Directive 89/104/EEC.

If the only guarantee of good water from waterworks is a good raw material, which flows into them, and if we do not have such a raw material, let us not delude ourselves that tap water is good, safe and healthy. The Act on Drinking Water and Domestic Water (NPP, Journal of Laws No. 35 of 4 May 1990) is simply adapted to our reality. That is how it allows for it:
5 times more arsenic,
10 times more benzene,
1,5 times more benzo(a)pyrene,
3.3 times more 1.2-dichloroethane than the European Union standard.

Polish regulations require only 43 elements and chemical compounds to be found in drinking water, which are harmful to our health, whereas in other European countries this number is as high as 250, and it must be believed that our law only takes care of the organoleptic properties of water, since in point 8 it allows “suspensions, dead and living aquatic organisms, oil stains, etc.”. provided that they are not visible in the glassware.

How can we count on clean drinking water when in Poland only 0.3% of the produced drinking water is drunk, i.e. out of 300 litres of drinking water leaving the waterworks, only 1 litre will be drunk? The rest is destined for industry and other domestic purposes, such as floor washing, bathing, toilet, etc.

It is no different in the case of well waters. Individuals rarely take care of their disinfection and “chemistry” is not affected by it either. No wonder that according to the reports of the sanitation, 80 – 90% of Polish wells have drinking water.

In Poland, drinking water is bad and dangerous, and many of the compounds it contains are even carcinogenic. An average Pole dies 9 years earlier than people living in the West. No one here is, of course, saying that it is only because of poor water quality, but we are deeply convinced that water makes a significant contribution to this mortality rate.

Many consumers save water by cleaning it with small, inexpensive household filters. Our market was even flooded with various mechanical and activated carbon filters. But let’s not delude ourselves, mechanical filters – as the name suggests – will only remove the undissolved mechanical parts, most often those that have no influence on our health. The only advantage of activated carbon filters is that they are sorbent in relation to chlorine, which is not lacking in water. And nothing else. Their great disadvantage is that they are also a source of bacteria, and dissolved compounds in water pass through them 100%.

Ladies and gentlemen, the problems described above are also faced by other countries in Europe and around the world. Our problems are much greater, however, due to years of neglect. Perhaps, therefore, the thesis of many scientists that also water from Polish taps has a significant impact on the highest mortality rate for malignant tumours in Europe is true. Let us finally open our eyes and try to understand why we know relatively little about the dangers of our water. The answer is simple – after all, it is our country that has a monopoly on the production of drinking water, at least that produced in water supply plants. After all, it was the erroneous policy of previous governments over many years that led to contamination of almost all fresh waters in Poland. In 1955 we still had 55% of water class I, in 1965 – only 35%, and in 1995 – 2.4%. Today, in turn, we hear more and more reports of contamination of deep water waters with surface chemistry.

But it is not only our governments and the green economy of most workplaces and factories that have led to this situation. The environmental awareness of our population also needs to be improved. I will just give you some examples. Only 20% of the oils for car engines sold in the whole country are recycled. The rest, mentioned in the backyards, in private garages, etc., is poured into the soil, canals, etc. And thousands of leaky or “quietly” empty household septic tanks? The Goczałkowice Lake, the largest retention lake in Poland, is accessed by the Vistula River with water of the 2nd class of purity, and despite the existence of an absolute protection zone around the entire lake, the wastewater poured into it causes the water leaving the lake to be non-classical. I would like to mention here that drinking water from Goczałkowice Lake is supplied to 5 million people of Upper Silesia and the surrounding area!

I think I should stop talking about this already. Maybe I am already dipping you in. Yet I was asked to discuss reverse osmosis. Very much, but I will perhaps start with another osmosis, namely the natural one, which we all know, after all. Yes, it is the one that occurs on the walls of human and animal cells. Natural osmosis consists in passing through the so-called semipermeable membranes of the solvent particles and not of the particles and ions dissolved in it.

Osmoza naturalnaNatural Osmosis

 

In water filtration technology, however, we care about something else. We want to “extract” part of the solution itself (i.e. clean water) from a solution of water at a certain concentration (dirty water), which in turn will make the solution even more concentrated. The movement of the solvent is exactly the opposite to that of natural osmosis. Hence the name of this new filtration technique, “reverse osmosis”.

This reverse movement of the solvent particles can be caused by applying the appropriate pressure on the appropriate side of the semi-transparent membrane, which in the technique is called the membrane. This pressure must simply be higher than the natural osmotic pressure in the water solution.

 

Osmoza odwróconaReverse Osmosis

 

Experiments with osmotic membranes were carried out as early as the 19th century in many laboratories and scientific centres around the world. Already in the interwar period, renal dialysis was started with reverse osmosis water. However, a milestone in this area was the invention in 1952 of new materials for the production of these membranes, namely polyamides. They replaced less durable and less efficient cellulose membranes. It was then that Professor Sourirajan from the University of California showed how effectively and accurately sea water could be cleaned on next-generation membranes.

The US Government reacted swiftly to the results achieved. Scientists have been allocated huge amounts of money for further research and the first high-performance osmotic filters for drinking water treatment have begun to be produced. Initially, they were used in the arms and computer industries, as well as in space flights. Previously, submarines, which had been cruising for many months, had to take with them quite a lot of clean water to drink. Such a system has now been changed by osmotic filters, which produce drinking water from sea water.

Similar filter units are already available in Poland. In the “Dębieńsko” mine near Rybnik, experimental osmotic filters are used to clean the brine extracted from the depths of the mine. The “Coca Cola” Group produces its refreshing beverages from water cleaned with reverse osmosis. The well-known Bonaqua mineral water is also cleaned with reverse osmosis and then artificially enriched with minerals.

But reverse osmosis is also used in millions of homes in different parts of the world. Such household osmosis filters were started to be produced in the USA in 1965. In most rich countries of the world, tap water was no longer used for drinking many years ago. The people of these countries have a choice: to buy drinking water in shops or to clean their domestic water with osmotic filters.

Reverse osmosis treatment of drinking water is rapidly gaining ground for two reasons:

Deep-water waters are in most cases also contaminated with chemicals that have “penetrated” from the surface into them;
The costs of the current operation of osmotic devices are so low that the water purified with them is from several to several times cheaper than the water offered commercially.

The porosity of the osmotic membranes can be freely adjusted. This ensures that the pores in the membranes used in drinking water systems are selected that are very easily permeable to mineral elements. It is used here that the ions of calcium, magnesium, sodium, potassium, etc. are very small and are similar in size to a water particle which easily penetrates through the pores of the membrane. At the same time, heavy metal ions, detergents, pesticides and all other compounds of modern organic chemistry are effectively retained, among which we increasingly note toxic compounds, as well as carcinogenic and even mutagenic ones.

Some suppliers of modern household osmotic devices additionally supply them with mineralizers, which enrich the output water with several elements of life. Such water has a composition of mineral water with a low degree of mineralization.

Ladies and gentlemen, due to far-reaching negligence in the field of ecology, we have brought about a situation in Poland in which we have practically no sources of clean, safe and healthy water. Our authorities are not doing much to prevent this, because there is no money for it. The average Pole does not know the whole truth, because he evaluates water by its colour and taste, and these properties do not say everything about it. We are poisoned with various factors, and to a large extent this is the case, for example, with the fact that we are at the forefront of cancer mortality in Europe. But if we are able to remove at least one of the carcinogens thanks to osmotic filters today, let us do so. It is up to you, ladies and gentlemen, how popular in the rest of the world, reverse osmosis, will be in our country. It is up to you whether, at least in this respect, we will go hand in hand with other civilised countries or remain in the Middle Ages.

Prof. Dr. Zygmunt Baranowski, PhD
VI National Scientific and Training Conference
Uniejów ’98