CS267764B1 - The method of neutralizing contaminated mineral acids - Google Patents

Abstract

Neutralization of mineral acids with calcium hydroxide is carried out. Mineral acids are neutralized with calcium hydroxide in the presence of a polyelectrolyte and the precipitated impurities are separated by sedimentation.

Description

Invention Heil neutralization of aineral acids which are contaminated with organic and inorganic substances.

Mineral acids, in particular sulfuric acid and hydrochloric acid, are very often used in industry. After use, often dilute mineral acids are formed, which are contaminated with organic or inorganic substances. These waste mineral acids must be neutralized before being discharged into watercourses.

The above shortcomings are mitigated by the method of neutralizing contaminated mineral acids which are contaminated with organic and inorganic substances. Of the organic substances, these are mainly oxygen, sulfur, nitrogen and chlorine derivatives of hydrocarbons. Of the inorganic substances, these are mainly sulfates, chlorides, cations of sodium, calcium, magnesium, iron, aluminum, zinc. The invention relates to the fact that the contaminated mineral acids are neutralized with calcium hydroxide in the presence of a polyelectrolyte and the precipitated impurities, in particular ferric, aluminum, magnesium and zinc hydroxides, are separated from the reaction mixture by sedination.

An advantage of the invention is that the contaminated mineral acids are neutralized with calcium hydroxide. During the neutralization, impurities precipitate from the aineral acid, which, after neutralization, are separated from the reaction mixture in the form of a sludge. The precipitated substances are, in particular, iron, aluminum, magnesium and zinc hydroxides from inorganic substances. The advantage is that the zinc content of the aineral acid is substantially reduced, which is toxic and causes difficulties when discharged into watercourses. Examples of organic substances are amines which are more soluble in an acidic medium than in a neutral medium, for example 2-isopropyl-4-ethylamino-6-chloro-S-triazine, which is used as a herbicide and should not be released into aqueous media. flows. Discharges of neutralized waste water will be eliminated by the fees charged to the flow manager for the discharge of acidic water as waste into the water stream.

Example 1

The contaminated mineral acid had the following composition:

ChSK / Cr, 2 h / 790 mg Oj / t pH value 1, , 9 1 650 mg / l Cl 1 125 mg / l M9 ^{2 +} 101 mg / l F. ³ * 18 mg / l Al ³ * 14 mg / l Zn ² * 8 mg / l

1 of the contaminated aineral acid was neutralized with 5% by weight, with suspension of calcium hydroxide to pH 7.8. Neutralization took place in the presence of polyelectrolyte. The precipitated impurities were separated by sedimentation.

The reaction mixture after sedation had the following composition.

ChSK / Cr, 2 h / 620 mg 0 _? / l pH value 7.8 ³ ^ 4 ^ ” 1,590 mg / l Cl 1,080 mg / l Mg ² * feet _ 3 + Fe feet Al ³ * 0.3 mg / l Zn ² * feet

In the discontinued sludge, they were able to org. 2-isopropyltino-4-ethylamino-6-chloro-S-trlazine.

The invention is useful in neutralizing mineral acids prior to their release

CS 267 764 B1 into a watercourse.

Claims (1)

from CS 267 764 B1 to an aqueous stream OF THE INVENTION The treatment of contaminated non-organic acids by organic solvents, nitrates, nitrogen oxides and chlorocarbons with hydrocarbons, inorganic substances, predominantly side-chlorides, sodium chloride, calcium, magnesium, iron, alumina and zinc with alumina characterized in that the mineral acid is neutralized with calcium hydroxide in the presence of polyelectrolyte and precipitated impurities of predominantly aluminum, magnesium, magnesium, ferric are separated from the reaction mixture by sedimentation.