SU719970A1 - Method of preparing mineral salt deposition inhibitor - Google Patents

Description

I - -.

The invention relates to the field of the production of substances added to these, the themes of recycled water supply to prevent deposits of minerals, precipitation, or scaling.

Known methods for producing inhibitors are based on the phosphorylation of nitrogen-containing compounds. For example, by the interaction of urea, ({) Ormald & hydrochloride and phosphorous acid obtained aminotri (methanophosphonic) acid ij. O (1) is efficiently used as inhibitors of polycomplexes with aminomethyl (yusphonic) groups, which are a mixture of sodium hexametaphosphate and polyethylene polyamine fij.

The closest to the invention in its technical essence and the achieved result is a method for producing polyelectrolyte consisting in treating polyethylene polyamines with formaldehyde and orthophosphorous acid in an aqueous hydrochloric acid medium Sj.

The disadvantages of this method are the low efficiency of the polyelectrolyte on carbonate and sulphate calcium salts, the complexity of the technology, the large amount of unused waste.

The purpose of the invention is to increase the inhibiting properties to prevent deposits of carbonate and sulphate calcium salts.

This goal achieves the use of not one nitrogen-containing compound (in the prototype, polyethylene polyamine), but a mixture consisting of polyethylene-ethylamine, monoethanol amine, carbamide, ammonium chloride and / or as an object of phosphorylation. hexamethylenetetramine in the following ratios, parts by weight: 1OO: 55-75: 25-40: 50-70: 34-45. Studies have shown the synergistic effect of this mixture of phosphorylated amines in. relation to the inhibition of precipitation of sulfate and carbonate calcium salts. Moreover, inhibition of

w W ± jr a b-v “c; b; J dftci CVU. it extends both to an increase in the induction period before the onset of crystallization of crystals, and to a decrease in the rate of crystal formation. After loading all the components, the nepaTjrpy in the reactor is raised to 98100 and maintained at this temperature (3 exposures less than 3 hours and at low temperatures the effectiveness of the inhibitor decreases). Then the reactor is cooled and when cooled, if necessary, it is neutralized with an aqueous solution of caustic soda. I get an inhibitor of SO74O% concentration. Example. 55 l of water, then 114 kg of technical phosphorous acid, 71 kg of 28% -: Noah of hydrochloric acid, 102 kg of formalin are loaded into an enamelled reactor with a reflux cooler, devices for mixing, measuring temperature, pH, heating and cooling. After mixing, 9 kg of polyethylene polyamine, 5.35 ammonium chloride or 5.7 ammonium chloride from a polyethylene production plant, 6 mono-ethanol amine, 3.5 hexg of methylene tetramine and 3 carbamide are added. After the end of the panning, the temperature of the reaction mass is raised to 98-1 with stirring and maintained at this temperature for 3 hours. Then the reactor is started to cool and neutralize the solution to pH 3, while cooling; gradually add 185 kg of 42% caustic soda. After neutralization, 553 kg of an aqueous solution containing 34% inhibitor is obtained. The rate of formation of precipitates of mineral salts on the surface of equipment and pipelines of water supply systems, the inhibitor dosage (calculated as 10%) is 4 Ntr / PR and M er 2. The equipment and the inhibitor production layers are the same as in Example 1, but ammonium chloride is not added to the phosphorylation reaction. Loading (kg); water 52 liters, technical. phosphorous acid 90, 28% acid copolyester 68, formalin 77, polyethylene, polyamine 9, monoethanolamine 6, urea 3, hexamethylenetetramine 3.5. Neutralization - 155 kg of 42% caustic soda. After neutralization, 463 kg of an aqueous solution containing 32%: inhibitor is obtained. Example 3: The equipment and conditions for preparing the inhibitor are the same as in Example 1, but hexamethylenetetramine is not introduced into the phosphorylation reaction. Loading (kg): water 58 l, technical phosphorous acid 9O, 28% hydrochloric acid 55, formalin 89, polyethylpolyamine 9, monoethanolamine 6, urea 4, ammonium chloride. 5.4. To neutralize - 145 kg of 42% caustic soda. After neutralization, 460 kg of an aqueous solution containing 33% inhibitor is obtained. Example 4: Equipment and conditions for preparing an inhibitor are the same as in Example 1, but the ratio of amines is different. Loading (kg): water 58 l, technical phosphorous acid 101, 28% hydrochloric acid 65, formalin 90 polyethylene polyamine 9, monoethanolamine 5, urea 2,3, ammonium chloride 4.5, hexamethylenetetramine 3. Neutralization - 164 kg of 42% caustic soda. After neutralization, 5OO kg of an aqueous solution containing 33% inhibitor is obtained. Example 5: The equipment and conditions for producing an inhibitor are the same as in Example 1, but the ratios of amines are different. Download (kg): water 50 l technical phosphorous acid 127, 28% - and hydrochloric acid 77, formalin 113, polyethylene polyamine 9, monoethanolamine 6.8, urea 3.6, ammonium chloride 6.3, hexamethylene tetramine 4. On neutralization - 204 kg of 42% caustic soda. After neutralization, 598 kg of an aqueous solution containing 35% inhibitor is obtained. Data on the effectiveness (degree of stabilization) obtained by the proposed method (examples 1-5) of the inhibitor compared with the prototype are presented in the table. 4 mg / L1 inhibitor concentration Nitrogen monoethanopamine, hexamethylenetetramine, ammonium chloride and carbamide. Techno-economical advantages of the proposed method for producing an inhibitor are a significant increase in the degree of stabilization, especially in carbonate salts and to simplify the technology and reduce the cost of production.

73,678, 8

Claims (3)

1. Patent of GDG No. 94993, class, 12O 26/01, 1973. 2. USSR author's certificate No. 548571, kp. C 02 B 5 / O6, 1977 3. USSR author's certificate No. 401692, cl. C O8 Q 33/06, 1972 (prototype),