MIL OSI Translation. Region: Russian Federation –
Decompose water into atoms and find 80 elements of the periodic table. The water quality control center has been operating in Moscow for 10 years.
Is it possible to drink tap water in Moscow without filtration and boiling? The specialists of the water quality control center guarantee: it is possible, the water does not require additional purification and it is absolutely safe to drink. For 10 years, the experts of the center have been strictly monitoring the purity and quality of drinking water.
Mos.ru visited laboratories at the Northern Water Treatment Plant and learned how the safety of water supplied to Moscow houses is checked.
Atoms, ions and 80 chemical elements
Today, the structure of the water quality control center JSC “Mosvodokanal”includes 11 departments that work at water treatment plants, treatment facilities and waterworks. Four more mobile express laboratories and several mobile teams are taking water samples on schedule at city offices and at repair sites on water networks.
At water treatment facilities, over 500 devices continuously monitor the main indicators of water quality at various stages. Daily operational control is carried out according to 30 basic physical, chemical and microbiological indicators. Regular extended water quality surveys include over 100 indicators. More than three thousand pieces of equipment are used daily for laboratory analysis of water.
The center, in fact, united separate production laboratories, which made it possible to make the process of checking the quality of drinking water in the city systemic, of high quality and less costly.
“In 2018, the direction of gas chromatography-mass spectrometric methods of analysis was organized at the Northern Water Treatment Station and high-precision modern equipment was purchased. The main indicators that are determined here are a wide range of metals and more than 40 organic compounds. Indicators such as, for example, cadmium, lead, mercury, thallium, are determined once a month. And in order not to overload the laboratories with equipment, it was decided to bring such rare analyzes from all over the city here. Previously, they were carried out on a contract basis, now we make them ourselves – it’s easier and cheaper. Samples come here from all water treatment stations and from the city distribution network, ”says Andrei Salgalov, head of the northern branch of the water quality control center.
The center is currently supported by over 400 qualified employees. 735 thousand samples are taken annually and 2.5 million analyzes are performed. No other water laboratory in the country performs such a volume of work.
Modern devices of Russian and Japanese production are capable of determining at least 0.5 MPC (maximum permissible concentration) of the most rare compounds.
To determine what metals and in what quantities are contained in water, a special device is used – an atomic absorption spectrometer. It measures the content of these chemical elements in water using flame atomization. In water vaporization, using a special lamp for absorbing light waves of a certain length, the device determines which elements have been detected and immediately transmits the data to the computer. Chromato-mass spectrometer and chromatograph can detect volatile organic compounds in water – benzene, vinyl chloride and others. The subject of special pride of the laboratory staff is an inductively coupled plasma mass spectrometer.
“This device makes it possible to determine about 80 elements of the periodic table. The principle of operation of the device is as follows: a sample of water enters the device, where it is not only atomized, but also ionized in argon plasma. Ionization occurs, ions enter the magnetic field. In it, each charged particle has the property of deflecting, and we determine the ratio of mass to charge by deflection and understand what kind of element it was. The device can operate in the range of up to picograms – this is 10 to the minus 12th power, ”says Andrey Salgalov.
To drink or not to drink?
The quality of drinking water in the capital is improving from year to year. A major breakthrough has been the use of sodium hypochlorite with ammonia water instead of conventional chlorine since 2012. The compound is added to water to prevent secondary contamination by bacteria or microorganisms on its way to the consumer. In other words, if a bacterium or a living organism gets into the water in the city water supply, sodium hypochlorite will not allow it to multiply and harm a person who drinks a glass of tap water.
Another advantage of this connection is its safety. Although in the capital, never in the entire history of the existence of the water supply system, there have been no major accidents with poisoning, pure chlorine in large quantities can be dangerous in the event of a leak. Hypochlorite – no.
“20 years ago there were no indicators that are now in SanPiN. They just weren’t tracked. Due to the tightening of requirements, new technologies and new equipment appear every 10-15 years, new parameters, indicators, values are monitored. The water, both before and now, meets all standards. The permitted chlorine content in drinking water in the city was, is and will be. And if someone is a little scared from this, I will say: it would be worse if he were not there. In this case, the multiplication of bacteria in water could happen very quickly, ”says Vyacheslav Fomin, deputy chief engineer of the Northern Water Treatment Plant.
Indeed, in the absence of such elements that allow maintaining the purity of the water, there is a small but risk that it will deteriorate on its way to the consumer. The fault may be low-quality house pipes (and this is already the responsibility of the management company) or an accident on the line.
“In Moscow, the water is actually quite soft, especially in the feeding zone of the Volga spring. Such water can be drunk as long as you want in any quantity, it is safe if the person does not have serious metabolic disorders. If the water smells like chlorine, it is 100 percent safe for the body. The water in Moscow meets all standards, it is one of the best in Europe, ”adds Andrei Salgalov.
It should be noted that safe drinking water cannot contain any bacteria or living organisms. At the same time, an insignificant concentration of inorganic substances in it – nitrates, fluorides, copper, manganese, iron and others – is allowed, since it is not capable of causing harm to the human body. If the water from the tap smells like chlorine (and this is possible, since sodium hypochlorite, like liquid chlorine, forms the same compound when it gets into the water), it is enough to let it settle for the smell to evaporate. However, the connection does not carry any harm to humans. Ammonia water is added for a chemical reaction. It does not reach the consumer.
From the Volga to the crane
The northern water treatment plant was built after the war and opened in 1952. At the same time, the settlement of Severny (now the Severny region) appeared as a place for housing workers. Elements of Soviet neoclassicism have been preserved in local architecture to this day. The halls in the blocks of treatment facilities are decorated with high arches, columns and other decorative elements.
The station provides drinking water to the northern part of the capital, Zelenograd and cities of the nearest Moscow region, such as Dolgoprudny, Khimki, Mytishchi. Water comes here from the Volga, the Uchinsky and Klyazminsky reservoirs.
Water intake takes place a few kilometers from the city. At the station, the water first enters the so-called mixer. This is a hall with pools, separated by blue partitions, in which it boils like a stream in spring. In the next room, the movement of water slows down.
“Due to the high speed in the mixer, the source water is mixed, and the reagent spreads in the water column much better, the reaction begins. Clarification of water occurs due to the fact that the coagulants have worked, and the suspension that was in the water sticks together and precipitates. This is the first stage of cleaning. After that, the clarified water is settled and filtered, ”explains Vyacheslav Fomin.
The filter room smells like a real sports pool. In a huge room with high vaults, there are several dozen containers into which water flows evenly. Slowly, the water in the pools flows through a layer of quartz sand and drainage. After filtration, it is distributed to underground reservoirs, from where it is pumped into the city system by pumping stations. The system of bright yellow pumps and bright green pipes works automatically, independently regulating the pressure of the water supplied to the city network. More in the morning and evening, less during the day and night. Previously, before the introduction of this system, water was supplied at constant pressure. This could lead to such manifestations familiar to many Muscovites, such as a drop in water pressure in the evening on the upper floors of houses due to the heavy load on the network.
Control at every stage
Water control at the station occurs at several stages: before water intake, after entering the water treatment system, as well as at each stage of purification. Sampling takes place centrally. In a special room, water supplied from different stages of cleaning flows into a large sink from a dozen taps. Here she is collected in flasks and sent for research.
Water quality control is carried out according to three types of indicators: physicochemical, hydrobiological and microbiological. Work goes on around the clock. The frequency of control depends on the indicators of SanPiN, some are checked once an hour. Laboratory assistants enter the data into a special system, then the station technologists study them to decide which reagents and in what quantities should be used.
A special department also checks the quality of reagents for water treatment – sodium hypochlorite and coagulants based on aluminum salts – aluminum polyoxychloride and aluminum sulfate. A sample is taken from each shipment. They come in the form of concentrated solutions and control them using special methods. A separate laboratory tests the water for microbiological indicators – the content of coliform bacteria and the total microbial count. For this, samples are poured through a special funnel onto a filter, which is placed in a nutrient medium, and then into thermostats, similar to small refrigerators, which at the same time keep the temperature at plus 37 degrees. In such conditions, microorganisms, if any, will begin to multiply rapidly and will be noticed. Checking water for hydrobiological indicators – phyto- and zooplankton – is carried out by the specialists of the center using microscopes with a magnification of up to 400 times.
Similar laboratories operate at each of the water treatment plants and also belong to the water quality control center.
EDITOR’S NOTE: This article is a translation. Apologies should the grammar and or sentence structure not be perfect.