SU776990A1 - Water softening method - Google Patents

Description

The invention relates to the field of water purification and can be used in heat and power engineering, ferrous metallurgy, chemical and petrochemical industries.

There is a method of drainless drain of water sodium-cation rovium. The essence of the method is that the initial water is filtered through cation exchanger in Na-form. The cation exchanger is regenerated by a solution of imported boiled salt. Neutral salt effluents from the regeneration of sodium-cation-exchange filters are evaporated in devices operating under (Vacuum. Then the resulting concentrate is buried or processed {I.

The disadvantage of this method is the pollution of the environment with a disposal center and a treatment associated with. the use of expensive stainless alloys in evaporation devices and the heat losses of the heating lars in them.

There is also known a method of water softening, which includes filtering the treated water through a Na-cation resin filter, regenerating the latter and oodo-liming the spent regeneration solutions in the clarifier:

The essence of the method is included in the fact that the softened water is filtered through Na-cation-exchange filters. The filters were regenerated with a concentrated solution of sodium salts. The effluents resulting from the regeneration of cation-exchange filters are pretreated by the lime-water method in a clarifier, and then evaporated in an evaporator and buried in special "burial grounds" 2.

The disadvantages of the method are environmental pollution with drainage drains and high cost of intelligence that is associated with the use of exhausters that are made of expensive stainless alloys.

The purpose of the present invention is

15 prevention of environmental damage and the reduction of the process to the gcheni mind.

The goal is achieved by the described method of water softening, including filtering the treated water through the Na-cation-exchange filter, regeneration of the latter and soda-water suspension of the regeneration effluent in the clarifier; with the initial water being treated in the ratio 0 ,,. 1b, ensuring the maintenance of fasting salt concentrations in

30 treated water for a total of

the softening cycle, preferably in an amount of 25-80% of their total volume, and the remaining amount is used to prepare a regeneration plant; d sodium-cationic filter.

A distinctive feature of the method is the machined; io oodo-known, forged effluents are lered by filtering water through sodium kytonitny FRI with the original treated GodoG; 3 at a ratio of 0.03–0.15, which ensures the maintenance of a constant mine, concentration of salts in the treated water during the entire cycle of intelligence.

Another difference lies in the fact that the soda- (lime: ICTOIKIH jumeses are watered with the original treated water in an amount of the total volume of the treated water, and the rest is used to prepare a regeneration solution for sodium cationite (filt.rap.

Technology implements the method consists in there, that is one of; after the body, the bodies are evenly metered during the cycle, processed in the stream, to the source water before softening. At the same time, depending on the type of cation exchanger and the composition of the source water, the effluent is metered into the source water stream before sinking in a ratio of 0.03-0.15. The amount of the dispensed wastewaters is maintained with the maintenance of a constant concentration of salt in the water being treated — and the condition of full utilization of the entire drainage cycle during the drainage period.

.Mypchapye water is carried out in sodium-cationic filters, after which water is directed to consumers of the softened

WATER1.

After depletion of the sodium-cation-exchange filter to the plug and hardness, it is regenerated by 2, (using a solution of sodium salts, the filter is washed away from the regeneration products. Regenerative drains, which include the used regeneration solution and part of the wash water, in which with an oleaginous bow more than in the source water, the IB tank of the waste solution is collected. The rest of the wash water (i3S-70%) is collected in the tank to be mixed with: Source water.

Otra, bot “regenerative water drains from

The waste solution tank is fed to a clarifier, where they are subjected to soda-lime treatment, thereby precipitating hardness salts in the form of removable sludge.

The treated sludge after clarifier is sent to the mixing tank with source water in an amount of 25-80%, from where they are mixed with neutral water, before filtering the latter through a sodium-cation filter, in a ratio of 0.03- 0.16, which ensures the maintenance of a constant salt concentration at 0: the water to be processed throughout the entire cycle of intelligence. In the remaining gummed drains, add the required amount of salt or concentrate of iop, the solvent to bring the concentration of the solution to 2.5- (8%), and are used in the next regeneration cycle of the Ka-1 ationite filter.

In this case, there is no need for expensive evaporators for the disposal of effluent, and a slight increase in the salt retention of the original zod fed to the sodium-satanite filter practically does not affect the exchange capacity of the cation exchangers and the residual rigidity of the filtrate.

Lhrime.R 1. In nat; sri-cation filter, loaded with KU-2-8, volume

1 m of the original water, having the following ionic composition, mg-eq / l: -

- 4.0; Cl-1 2, .0; CN-n 1.0; C o, 2.0; Sa

 0.1; Cnso ,, 4.0. Volume of waste

8% rebirth spraying at

The specific consumption of salt for the regeneration of 2 g-SQV / g-eq is 1.3 m. The volume of wash water is 5 m. The waste water collected in the waste solution tank during the regeneration process is 6.3 m.

Soda water is from the clarifier. The concentration of sodium salts in soda-limed effluent is 1.6%, due to the development of wash water.

According to the proposed method 80%

the volume of soda-and-zveshovansky effluent, i.e. 5 m, smeshvvak) T with the source water lered filtration of the latter through a sodium zhationitny filter in the ratio 0,0i3. The remaining 20% soda-limed

effluent, i.e. 1.3 m, is used to prepare a sodium-cation (nitric filter) regeneration solution by adding salt to the solution. The salt content of softened water is 17.2 mg-eq / l, and the exchange capacity of the cation exchanger is equal to 900 g-eq / m. The softened water is directed to feed the closed heat supply network. The specific consumption of imported salt for the preparation of regeneration

the solution is 1.7 g-eq / g-eq versus 2 g-eq / g-eq by the known method. The specific consumption mixed in the process of drainage mitigation is 0.03, which ensures the maintenance of a constant

the concentration of salt in the treated water (17.2) over the whole of the diclene is more abundant.

Example 2. p. In the sodium-cation filter, loaded with 1 m KU-2-8, the initial water is softened, with a composition similar to that in the example. L After the breakthrough of hardness into the filtrate, the filter is regenerated in countercurrent with a 2.5% solution of sodium chloride with a specific

consumption of 2 g-eq / g-eq. The amount of regeneration solution is 5 m. After regeneration, the filter is washed with 5 lg of softened water. The spent recycling solution with a volume of 5 n: and 34% of wash water, with a volume of 1.7 g, is made up of soda-lime in the clarifier. The concentration of soda water is 1.9%. The remaining 3.3 m of wash water with a concentration of hardness salts less than 6 mg-eq1l is collected in a tank of wastewater mixed with the source water. According to the foregoing, 25% of the soda-lime effluent, i.e., 1.7 g, is sent to the tank of the mixed effluent and is mixed with the initial water before the filtration of the latter through a sodium cathiopite filter. The specific consumption of mixed wastewaters is 0.06, and the salt content in the softened water is 10.6 meq / l, which is acceptable for feeding open heating networks. The exchange capacity of the cation exchanger is 900 g-eq / m. The remaining 75% of 5 L soda-lime effluent with 1.9% sodium salt concentration is used to prevent fresh regeneration solution by adding iiOiBaipeHHou salt. The specific consumption of imported salt: per regeneration is 0.6 g-eq / g-eq. When using low-intensity sulfonated-type cation exchangers, the ratio of wastewater mixed with the source water, ensuring the maintenance of a constant salt concentration in the treated water, reaches 0.15. Thus, the use of the proposed method of water softening eliminates contamination of the environment with Na-cationic effluents (filters without using expensive evaporators and reduces the specific consumption of reagents for regeneration. Considering that the cost of evaporators is about 95% of the total cost. "The tail part of the water treatment plant and they require a large expenditure of steam, the elimination of this equipment and the cost of heat from the steam makes it possible to obtain great savings. So, with productivity, the mind The estimated 2000 ton / h of annual savings from using the proposed icnoco6a is approximately 2.0 million rubles. The formula of the invention: neither 1.iCnoco6 water softening, including filtering the treated water through a sodium-cation-exchange filter, regenerating the latter and reducing spent reheperative wastewater in a clarifier, characterized in that, in order to prevent contamination of the environment and making the process less expensive, co-limestone wastewaters are mixed with the source water before filtration of the latter through sodium cation exchanger. second filter at a ratio of 0.15 0,03- providing lodderzhamie constant kontsentraschii salt in treated water over a cycle softening. 2. A method according to claim 1, characterized in that the sodo-precipitated drains for mixing with the source water are taken in an amount of the whole of their volume, and the remaining 20-7 ~ 5% is used to prepare a regeneration solution of a sodium-cation-exchange filter. Sources of information taken into account in the examination: 1. Abstracts of the All-Union Scientific and Technical Conference "Thermal methods of water treatment at thermal power plants and research problems, Chel binsk, 1977, p. 64-66. 2. "Thermal engineering number 2, 1976, p. 60 (prototype).

Claims (2)

Claim 1. (A method of water softening, including filtering the treated water through a ¹⁵ sodium-cation exchange filter, regenerating the latter and soda lime recovery waste water in a clarifier, characterized in that, in order to prevent pollution of the environment ²⁰ and reduce the cost of the process, the soda lime waste is mixed with source water before filtering the latter through a sodium cationic filter in a ratio of 0.03— 0.15 g ³ / g ³ _l providing 25 constant concentration of salts in the treated water for a period of this softening cycle. 2. The method according to π. 1, characterized in that soda lime wastewater for. 30 solutions with source water are taken in the amount of 25–80% of their total volume, and the remaining 20–75% are used to prepare the regeneration solution of the sodium-cation exchange filter.