CS267902B1

CS267902B1 - The process of neutralizing waste mineral acids

Info

Publication number: CS267902B1
Application number: CS868657A
Authority: CS
Inventors: Vladimir Ing Zeljazkov; Peter Ing Hauskrecht
Original assignee: Zeljazkov Vladimir; Hauskrecht Peter
Priority date: 1986-11-26
Filing date: 1986-11-26
Publication date: 1990-02-12
Also published as: CS865786A1

Abstract

Rieši sa neutra1 izácia odpadných minerálnych kyselin vznikajúcich v chemickom priemysle. Odpadně minerálně kyseliny sa predneutralizujú s odpadnými alkalickými vodami z kryšta 1 izácie 3-metyl- -4-nitrufenolátu sodného a doneutral izuje sa s hydroxidom vápenatým. Vyzrážané nečistoty sa oddelia s výhodou v přítomnosti polyelektrolytov.The neutralization of waste mineral acids arising in the chemical industry is addressed. Waste mineral acids are pre-neutralized with waste alkaline waters from the crystallization of sodium 3-methyl-4-nitrophenolate and are further neutralized with calcium hydroxide. The precipitated impurities are preferably separated in the presence of polyelectrolytes.

Description

CS 267 902 01 1EN 267 902 01 1

Vynález rieši neutrali žáciu minerálnych kyselin, ktoré sú znečistěné s organickýmia anorganickými látkami. V priemysle sa velmi často použivajú minerálně kyseliny, predovšetkým kyselina sí-rová a kyselina chlorovodíková. Po použití vznikajú často zriedené minerálně kyseliny,ktoré sú znečistěné s organickými alebo anorganickými látkami. Před vypuštěním do vodnýchtokov je nutné tieto odpadně minerálně kyseliny zneutra 1 izovať, čo sa najčastejšie robí s hydroxidům vápcnnatým. V chcmickom priemysle často vznikajú alkalické odpadně vody, ktoré pozostavajú pre-dovšetkým zo znečistěných alkalických hydroxidov. Před vypúšťaním do vodných tokov samusia alkalické odpadové vody neutralizovat’, čo sa najčastejšie robí minerálnymi kyse-linami. Určitá nevýhoda při neutralizovaní kyslých vod je, že sa používá hydroxid vápena-tý a pri neutrali žáci i alkalických vod sa použivajú minerálně kyseliny, čím sa zvyšujúnáklady na vypúšťanie odpadových vód.The invention addresses the neutralization of mineral acids contaminated with organic inorganic substances. Mineral acids, especially sulfuric acid and hydrochloric acid, are very often used in industry. After use, often diluted mineral acids are formed which are contaminated with organic or inorganic substances. Before being discharged into water streams, these mineral waste acids need to be neutralized, which is most often done with calcium hydroxide. Often alkaline effluents are formed in the chemical industry, consisting mainly of contaminated alkali hydroxides. Before discharging into watercourses, neutralize the alkaline waste water, which is most often done by mineral acids. A disadvantage of neutralizing acid waters is that calcium hydroxide is used and mineral acids are used in the neutralization of both students and alkaline water, thereby increasing the cost of discharging waste water.

Vyššie uvedené nedostatky sú zmiernené spósobom neutra1 izácie odpadných minerálnychkyselin, znečistěných organickými a anorganickými látkami. Z organických látok sú to kys-líkaté, sírne, dusíkaté a ch1 ordcriváty uhíovodíkov. Sú to odpadné produkty prevaéne zvýroby pesticídov a z výroby gumárenských chemikálií. Z anorganických látok sú to najmasírany, chloridy, kationy sodíka, vápnika, horčíka, železa, hliníka, zinku, ktoré vzni- 'kajú při kondenzačných reakciách organických zlúčenín, při aklivácii bentonitu, pri re-dukcii organických zlúčenín, při nitrozáciach organických látok a pod. Odpadné minerálněkyseliny sa predneutralizujú s roztokům sodnej soli 3-metyl-4-nitrofenolu znečistenejso sodnými sofami 3-mo ty 1 f erio lu a jeho nitro-sulfo, nitrozoderivátmi a hydroxidom sodným.Heakciuu s minerálnymi kyselinami vzniknú sodné soli minerálnych kyselin, 3-metyl-4-nitro-fenol, 3-metylfenol aj jeho nitro-, nitrozo- a sulfoderiváty. Při koncentráciách přibliž-né nad 1500 mg/1 3-moty 1-4-nitrofenol sa vyzráža a vyzrážaný 3-metyl-4-nitrofenol sa zreakčnej zmesi oddělí, s výhodou sedimentáciou. Reakčná zmes sa potom doneutralizuje sosuspenziou hydroxidu vápenatého na hodnotu pH 5 až 8, s výhodou 6,5 až 7,5.The aforementioned drawbacks are alleviated by the method of neutralizing waste mineral acids contaminated with organic and inorganic substances. Of the organic substances, these are the oxygenated, sulfuric, nitrogenous, and quaternary hydrocarbons. They are waste products of the prevalence of pesticide production and the production of rubber chemicals. Of the inorganic substances, these are the most disulphates, chlorides, cations of sodium, calcium, magnesium, iron, aluminum, zinc, which are formed by the condensation reactions of organic compounds, in the bentonite reaction, in the reduction of organic compounds, in the nitrosation of organic substances and the like. . The waste mineral acids are pre-neutralized with solutions of 3-methyl-4-nitrophenol sodium salt contaminated with sodium salts of 3-methyl-4-nitrophenol and its nitrosulphonate, nitrosated derivatives, and sodium hydroxide. 4-nitro-phenol, 3-methylphenol and its nitro-, nitroso- and sulfoderivatives. At concentrations above about 1500 mg / l-3-methyl-4-nitrophenol, the precipitated 3-methyl-4-nitrophenol is precipitated from the reaction mixture, preferably by sedimentation. The reaction mixture is then neutralized with the calcium hydroxide sosuspension to a pH of 5 to 8, preferably 6.5 to 7.5.

Doneutralizácia sa rotit v přítomnosti po 1 yel ek t roly tu. Vyzrážané nečistoty, predovšetkýmanorganické hydroxidy ako Fe(CII)j, MgCOH)?, ZníOH)^, ΑΚΟΗ)} sa z reakčnej zmesi oddelias výhodou sedimentáciou. Výhodou podl’a vynálezu je, že sa na predneutralizáciu odpadných minerálnych kyselinpouživajú odpadné alkalické vody. Vzájomnou reakciou odpadných minerálnych kyselin a od-padných alkalických vód vznikajú menej znečistěné odpadné vody ako při neutralizáciiodpadných minerálnych kyselin iba s hydroxidom vápenatým a neutralizácii odpadných alka-lických vód s minerálnymi kyselinami. Postupom podlá vynálezu, vzhfadom k tomu, že dójdek vyzrážaniu a oddeleniu časti nečistot z reakčnej zmesi vo formě kalu, do vodného tokusa dostane menej nečistot ako keby sa vypúšťali odpadné minerálně kyseliny a odpadnéalkalické vody do vodného toku samostatné. Vypúšťaním zneutralizovaných odpadných vódsa odstránia poplatky, ktoré sa musia platil’ správám toku za vypúšťanie kyslých, aleboalkalických odpadných vód. Příklad 1Donutralization rotates in the presence of a single tube here. Precipitated impurities, especially inorganic hydroxides such as Fe (CII), MgCOH, ZnOH, AOH, are preferably separated from the reaction mixture by sedimentation. It is an advantage of the invention that waste alkaline waters are used to pre-neutralize the waste mineral acids. The reaction of the waste mineral acids and the alkaline waters involved results in less polluted wastewater than in the neutralization of waste mineral acids only with calcium hydroxide and neutralization of the waste alkali water with mineral acids. According to the process of the present invention, since the precipitation and separation of the impurities from the reaction mixture in the form of sludge is reduced, less impurities will be introduced into the aqueous stream than if the discharged mineral acids and waste water were discharged separately. Discharges of neutralized waste water will remove the charges that have to be paid to the flow management for the discharge of acidic, or alkaline wastewater. Example 1

Odpadná mincrálna kyselina inala následovně zloženie: ' tThe wasted microcrystalline acid has the following composition: t

ChSK (Ur, 2 tiud) 790 myO^/l hodnota pil »,9 2- so/ 1650 mg/1 Cl 1125 mg/1 Mg2' 101 mg/1COD (Ur, 2 tud) 790 myO ^ / l value of piles », 9 2- so / 1650 mg / 1 Cl 1125 mg / 1 Mg2 '101 mg / 1

Claims

2 CS 267 902 B1 Fe Al Zn 10 ing / 114 mg / 1 0 mg / 1 Waste alkaline water from the crystallization of 3-methyl-4-nitrophenolate sodium has the following composition: 3-methyl-4-nitrophenol sodium salt 10 g / 1 moreover, 3-methylphenol derivatives of 3.9 g / l NaCl 124 g / l pH of 11.2 K1 waste mineral acid was added 100 ml of waste alkaline water. The precipitated impurities were separated from the reaction mixture by sedimentation. Then the reaction zines were neutralized with 5 wt. calcium hydroxide suspension to pH 7.5. Donutralization was performed in the presence of 0.01 g of polyelectrolyte (magnofloc). The precipitated impurities were separated by sedimentation. Example 2 The procedure of Example 1 was followed except that the waste mineral mineral acid was pre-neutralized with the alkaline waste water to a pH of 3.2. After separation of the precipitated impurities and neutralization with calcium hydroxide in the absence of polyelectrolyte, the pH of the reaction mixture was 5.4. The precipitated impurities were separated by sedimentation. The invention can be used to neutralize waste mineral acids if alkaline effluent from crystallization of 3-methyl-4-nitrophenate sodium is formed in the plant. EXPLOSION FOR THE DISPOSAL The method of neutralizing waste mineral acids contaminated by organic substances with oxygen, sulfur, nitrogen and chlorinated hydrocarbons, inorganic substances, especially sulphates, chlorides, cations of sodium, calcium, magnesium, iron, aluminum, zinc, alkali, that the waste mineral acids are pre-sterilized with a solution of sodium methyl 4-nitro-nitro-sodium contaminated with the sodium salts of 3-methylphenol and its nitro, sulphonate and nitrosated derivatives and sodium hydroxide, and preferably 3-methyl- precipitated after the pre-neutralization. The 4-nitrophenol is separated from the reaction mixture by sedimentation, and the reaction mixture is neutralized with calcium hydroxide, preferably in the presence of a poly-electrolyte, and the precipitated impurities are separated from the reaction mixture by sedimentation.