PL154036B1 - Method of treating acid and very soft waters - Google Patents

Description

REPUBLIC POLAND PATENT DESCRIPTION 154 036 Additional patent to patent no. --- Int CS. ⁵ CO2F 1/66 Reported: 87 03 09 / P. 264516 / Priority - Wrap H 61 O & OFFICE PATENT Application announced: 88 10 27 RP Patent description published: 1991 1129

Creators of the invention: Tadeusz. Kowalski, Apolinary L. Kowal, Mirosław Kurczyn, Henryk Sobociński

Authorized by the patent: Wrocław University of Technology,

Wroclaw / Poland /

THE METHOD OF TREATING ACID AND VERY SOFT WATERS

The subject of the invention is a method of treating acidic and very soft waters, especially Sub surface waters of groundwater for municipal industrial purposes.

The previously known method of treating acidic and very soft waters consists in adding calcium salt to the water to adjust the pH, and then filtering through a sand filter and a carbon filter to remove dissolved organic impurities and final disinfection.

The main disadvantages of this method of treatment are the need for a very accurate dosage of calcium hydroxide, which requires the use of automatic control of the pH correction, the need to use small doses of calcium hydroxide, which means that the water has no buffering and thus is magnesium-free and contains little calcium, the need to use sorption on carbon inability to treat water contaminated with suspended sub-colloidal suspensions. An additional disadvantage is that coagulation cannot be used due to the lack of alkalinity.

There is also another method of treating acidic and very soft waters. It consists in the initial aeration of these waters for about one hour in order to remove carbon dioxide, filtration through the sand filter, sorption on activated carbon and disinfection.

The main disadvantages of this treatment method are the need for a long retractor, the need to use sorption on activated carbon, and the inability to treat water contaminated with sub-colloidal suspensions.

The essence of the invention is that carbon dioxide is introduced into the water in an amount resulting from the estimated final alkalinity and pH, and then passed through a bed of calcined dolomite. The following reactions take place in the roasted dolomite bed

MgO + 2CO ₂ + H ₂ 0 - »Mg / HCO _3/2

CaCO ₃ + 0) 2 + H2 ⁰ Ca-c / OCO _3/2

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As a result of the reaction of the introduced carbon dioxide with the components of roasted dolomite, calcium and magnesium bicarbonates pass into the water. The dissolution of the roasted dolomite bed causes the moodiness of the surface of the mass, improving its sorption properties.

The essential advantage of using the treatment method according to the invention is that it makes it possible to obtain water with the required alkalinity and pH as well as magnesium and calcium content. Another advantage is that organic pollutants and manganese are sorbed on the surface of the roasted dolomite bed. Another advantage is that in the case of waters contaminated with hardly settling or colloidal suspensions, coagulation can be used.

The subject matter of the invention is presented in practice.

EXAMPLE I The following water parameters, namely, pH 4.7, 5 g CaCO zasadowoś ^Æ ~ / m ^3, hardness, and i ^by n, the calcium content of web ^Æ 5 ^g Ca / m '\ ^Æ magnesium zaw3Γtżś 1.7 ^g Mg / m ^ / ** 3 3 manganese content 0.14 g toi / m, oxidation 4g 0o / m, carbon dioxide is introduced in the amount of 3 · c and 60 g COg / m, and then it is passed at a speed of 10 m / h through a deposit of roasted dolomite with the trade name Dooiitr mass. The roasted dolomite bed is 120 cm high and the flow is from top to bottom. Roasted dolomite with the trade name Dooiltr mass, originating from the Maria deposit in Stronie Śląskie, has the following parameters, namely the total calcium content in CaO about 30%, calcium oxide CaO about 2%, the total magnesium content in MgO about 20% , magnesium carbonate MgCO ^ approx. 10%, total oxide content / Alg0g + Fe ₂ 03 + TiOg / approx. 1.5%, weight loss on ignition at the temperature

1200 ° C about 40%. Obtained treated water of następująoych parameters, namely ^p H = ^{7, 3 6,} zasadowoto Tokle 80 ^g / m ³ TWAR ^d ZS ^C6, n ° l, content; of calcium 18.2 ^g Ca / m ^, the content of magnesium was 14.3 g Mg / m3, oxidability 1.8 g 02 / m

Example II The following water parameters, namely, pH = 5.25, ^bases Wos ^Æ CaOk ^5g / m ³ twardoś ^ClO, and n ° content; Calcium ⁵ to ^{7 g} / m ^ ^ magnesium content ^{of 1.3} M / m ^

3 ° 3 3 turbidity 15g / m, color 40g Pt / m, oxidisability 12g 0 ₉ / m, carbon dioxide is introduced in the amount of 95g COg / m and 20g of eighteen-centimeter aluminum sulphate Al2 / S04 / g18Hg0, and then passed at 5 m3 / h through a calcined dolomite bed As in Example 1, then passed through a sand filter from top to bottom at 5 m3 / hr. A treated water with the following parameters is obtained, namely pH = 7.6, alkalinity 115 g 3 by 3 3

Cad,. / M, hardness 7.6 n, calcium content 15.7 g Ca / m, m ^^ nezium content 23g Mg / m, moth 3 3 g / m, color 10g Pt / m, oxidation 3g 02 / m.

Claims (1)

Patent disclaimer A method of treating acidic and very soft waters, especially surface or groundwater for domestic or industrial purposes, characterized in that carbon dioxide is introduced into the water in an amount equal to the required final alkalinity and pH, and then passed through roasted dolomite bed. Department of Publishing of the UP RP. Circulation 100 copies Price: PLN 3,000