DE561070C - Treatment of water and waste water - Google Patents

Description

GERMAN EMPIRE

ISSUED ON
OCTOBER 10, 1932

REICH PATENT OFFICE

PATENT LETTERING

CLASS 85b GROUP

Chemical factory Budenheim Akt.-Ges. in Mainz*)

Treatment of water and wastewater Patented in the German Empire on October 11, 1930

The naturally occurring waters often have a disruptive organic content Substances such as humus substances, decomposition products of faeces, industrial waste and the like, often with earthy substances or clayey turbidity mixed up. This is often the case with surface water, but also with groundwater and in rivers Case. This water can usually not even be used as service water or boiler feed water be used, especially not as water for municipal water pipes, for paper mills, dye works, laundries, bleaching plants and the like, for which a colorless, clear water is required. in the Steam boilers cause such water to foam and spit, although they are often the result the lack of or low hardness are ideally suited for this. For drinking

ao water purposes is such a water from unsuitable for hygienic reasons.

Such waters are already available with aluminum sulphate or ferrous sulphate and lime, also loaded with permanganate or chlorine

«Acts to eliminate the organic matter. However, there are shortcomings in these procedures. So increases z. B. aluminum sulfate the sulfate content of the water, which is particularly made noticeable by the effect of corrosion in the steam boiler. Hydrogen sulphide, which is an organic putrefaction product Substances occurs, is not included, for example. Increase ferrous sulphate and quick lime the hardness of the water due to the formation of calcium sulphate. Permanganate and chlorine are partly expensive, partly difficult to dose and the water treated with them is difficult to get rid of the excess of the treatment agent.

It is also known to remove organic contaminants from wastewater by that so much monocalcium phosphate is added that dicalcium phosphate is added by reaction with the hardness constituents present arises; If there are no hardness components, calcium hydroxide must be added in the calculated amount. During the formation of the dicalcium phosphate, the impurities become torn down and together with the phosphate form a fertilizer.

Finally, it is also known to use products for the treatment of wastewater, obtained from aluminum phosphate and hydrochloric acid. These products are mixtures of aluminum chloride with phosphoric acid. Aluminum chloride is in these mixtures the precipitant acting on the organic matter; the phosphoric acid present only serves to make the precipitated organic matter to produce fertilizers containing phosphoric acid.

It has now been found that water-soluble phosphoric acid salts of heavy metals in are effectively suited to all organisa-

*) The patent seeker stated as the inventor:

Dr. Guido Hedrich in Budenheim.

see substances and their decomposition products, cloudiness and color in water to eliminate. All that is required is that the metal phosphates that are used come, are water soluble. As such, z. B. acidic phosphoric acid salts of Iron, manganese and other heavy metals or mixtures thereof. Your application happens in such a way that the water is more usual in any suitable apparatus Type of construction, optionally with heating, in a continuous or discontinuous Method is mixed with a metered amount of the metal phosphate in substance or in '5 solution, with flakes being formed which are separated in any manner, for example filtered off. Depending on the nature and the purpose of use, the water is before or after clarification with alkalis, such as soda, alkali phosphates or lime corrected. General guidelines can be found in the fluctuating composition of the natural and the Do not give sewage.

The new process is characterized by the fact that not only the organic impurities, but also the hardness in the presence or artificially generated alkalinity due to the phosphate content of the cleaning agent is completely removed if the intended use makes this necessary, e.g. B. when using the water to feed the boiler; this also has the advantage that a low content of P ₂ O ₅ can be set in the treated water, which for. the steam boiler operation is particularly favorable.

Examples

i. A yellow-colored well water with ^{2 m} 75 g Na ₂ CO ₃ per liter and a permanganate of 85 mg of the permanganate was liter by heating to 70 ⁰ C it 37 ^{m 1} S Ferro monobasic orthophosphate,

FeH ₄ (PO ₄ ) ₂ 2H ₂ O added per cbm of water. Flakes formed which were filtered off. The water became completely colorless and colored pink after the addition of the first drop of permanganate solution.

The water that is used as boiler water due to the high content of organic substances was unusable, is now suitable for direct boiler feed without further post-treatment.

2. A very cloudy river water of 18 ° total hardness and 6 ° permanent hardness as well as a permanganate consumption of 56 mg per liter was mixed with 0.5 kg doubly acidic manganese phosphate, MnH ₄ (PO ₄ ) ₂ 2H ₂ O per cbm and from the freed flakes by filtration. After heating to 70 to 80 ° C., 0.57 kg of calcined soda per cbm of water were added, as a result of which all hardness components were quantitatively precipitated. The purified water is colorless, completely clear, free of organic substances and has the hardness o.

3. Water with a total hardness of 21 ° with a consumption of 2.8 ecm 0.1 η hydrochloric acid for 50 ecm water. A consumption of 28.4 mg potassium permanganate in the liters of water both at 20 and at 75 ⁰ C again with 0.1 gram mole. Monocalcium phosphate and, on the other hand, 0.1 gramol. Manganese phosphate added. After a reaction time of one hour, the resulting flakes are separated off by filtration. All four waters are clear and colorless. Adding equal amounts of sodium hydroxide solution causes the phosphates still in solution to precipitate, once again at 20 ° C and the other time at 75 ° C. After another filtration, an examination of the water shows the following result:

a) Monocalcium phosphate treatment at 20 ° C. Hardness of the water 3 ⁰ , permanganate consumption per liter 10 mg.

b) Monocalcium phosphate treatment at 75 ° C. Hardness of the water 2 °, permanganate consumption per liter 12 mg.

c) Monomanganate phosphate treatment at 20 ° C. Hardness of the water 0.25 °, permanganate consumption 2 mg per liter.

d) Mono manganese phosphate treatment at 75 ° C. Hardness of the water o °, permanganate consumption ι mg per liter.

The comparative experiments show that the monomanganese phosphate is much more effective is than the monocalcium phosphate.

Claims (1)

Claim: Process for the treatment of water and waste water, in particular organic Waters containing substances, characterized in that the water is optionally heated with water-soluble heavy metal phosphates, for example acid iron or manganese phosphates or mixtures of such substances.