SU1270118A1 - Method of continuous ion-exchange treatment of water - Google Patents

Abstract

The invention relates to methods for continuous treatment of water with ionites in a fixed bed and improves the stability of the cleaning mode, the reliability of process control and the reduction of reagent and water consumption for own needs. Water treatment is carried out on a group of six or more ion exchange filters connected in series in the ring. Cleaning process is divided into stages and operations that are constant in duration, equal in time to the shortest operations, loosening or washing. The stages of filter regeneration and water reduction are divided into stages, and the beginning of each stage or operation is carried out on all filters of the group simultaneously. 1 il. 1 tab.

Description

yu | The invention relates to the purification of water by ion exchangers and can be used in the energy, chemical, metallurgical and other industries. The purpose of the invention is to increase the stability of the cleaning mode and to save reagents. The drawing shows a scheme for carrying out the method of continuous ion-exchange water purification, comprising a group of six ion-exchange filters connected in series in a ring. Legend of technological operations: Y - softening, O - washing, P - regeneration, B - loosening. Water softening includes the stages: basic (U) and barrier (U) cleaning. The regeneration of the filters is carried out at the stage of primary (P) and preliminary (PJ) regeneration. Complete filtration of purification includes six stages of operation of each filter (a, b, c, d, e, f). In the initial state of O. in the figure, the following sequence of operations of ion-exchange water purification is adopted. The 1st filter works as a basic filter of water softening until it is completely depleted - Stage Y - The 2nd filter works as a protection against hardness ion leakage when the first filter is depleted - the barrier cleaning stage U, On filters 1,2 perform an operation mind water, including basic and barrier purification steps. In the 3rd filter, the ion exchanger is treated with softened water partially withdrawn from the 2nd filter, the operation is washed out 0. In the 4th filter, the cation exchanger is regenerated with a fresh solution of the reagent and reagent displaced from the 3rd filter - stage of main regeneration P. In the 5th filter, the regeneration is performed with a solution that has passed through the 4th filter in order to more fully utilize the reagent and reduce the amount of waste — the pre-regeneration stage P ,. Filters 4, 5 carry out the ionite regeneration operation, which includes the stages of primary and preliminary regeneration. 18 .. In the 6th filter, the operation of loosening B of an ion exchanger after complete depletion of B is performed. In the next step b: the 1st filter, completely depleted, is set to loosening B: the 2nd filter, working as a barrier filter, is for basic cleaning; The 3rd filter includes as a barrier after the 2nd filter (PP) i. water softening is carried out on filters 2,3; The 4th filter after regeneration includes washing O; The 5th filter includes the main regeneration with fresh solution of reagents P. after preliminary regeneration; The 6th filter is switched on for preliminary regeneration P after loosening, thus regeneration at this stage is carried out on filters 5, 6. At subsequent stages c, d, e, f, the operations are identical, with the difference that the filters with each stage are shifted for one: the 2nd filter takes the 1st filter, the 3rd - the second, the 4th - the third, the 5th - the fourth, the 6th - five, the 1st sixth, etc. After passing the complete filter cycle, the filter E returns to its original position. In the proposed method, the duration of the flushing and washing operations are equal to each other, and the clearing and regeneration operations are carried out in two stages, the duration of each of which is equal to the duration of the loosening or washing operation. :. The shift of the beginning of the specified cyclic | Coy sequence to the next filter is carried out after completion of the washing and loosening operations. Thus, the beginning of each stage and operation on all filters of the group is carried out simultaneously. Example. Sodium cation extinguishing of the high-meson | LIZovannogo water, the composition close to the reservoir waters of oil fields. . The input of the 1st filter operating in the main cleaning mode, serves the source water of the following composition. . total salt content (Cp) 4 and Omg-eq / l; total hardness (g-) 80 meq / l; calcium hardness (lm 16 mEq / l. From the output of the 1st filter, partially softened water is fed to the inlet of the 2nd filter. At the same time, the hardness of partially softened water in the process of depletion of the 1st filter increases from the equilibrium hardness of softened water to hardness I1: running water. At the output of the 2nd filter, a softened water is obtained, which is sent to the consumer. The hardness of softened water (GW) 0.2 mg-eq / Part of a soft water (12%) JY 0.2 mg-eq / l is fed to the inlet of the 3rd filter to clean the ion exchanger from the regeneration solution. The regenerating solution is fed to the inlet 4 of the filter. Simultaneously with the stream of wash water to the inlet of the 4th filter ::: 2 Regeneration ;: solution; from the end serves peienc aM, I.-.- j1 concentration (Cfp) 2200 mg eq / l in the amount of 6.4 eq salt / eq. From the output of the 4th filter, the partially spent regeneration solution is fed to the inlet of the 5th filter. The spent solution from the output of the 5th filter is discharged to the drainage. th filter serves source water for loosening. Specific consumption of water for loosening (tp) is 3.3%. The main comparative indicators of the filter cycles of the prototype and the proposed method are given in the table, where Е „„, (mg-eq / l) is the total capacity of the FULL., V absorption of the cation exchanger; Zhu / mEq / l} residual water hardness after cleaning; g (kg / m) is the specific consumption of the reagent (NaCl) per unit volume of the cation exchanger; tsn () - specific consumption of water for own needs are related to the capacity of the installation. The advantages of the proposed method in comparison with the known conclusion are in increasing the stability of the process control system and reducing the consumption of reagents and water on its own.

Indicators

Gobl mg-eq / l

Way

Famous Proposed 1002 0.2-0.3 374.5 15.3

P1sts

R,

kg / m

7

Claims (1)

850 0.4-06 440 22 118 personal needs. This is achieved due to the fact that the selected time interval for simultaneous transfer of all filters from one operation (stage) to another is carried out according to the shortest operation (agitation or washing). This allows, on the one hand, to increase the stability of the cleaning mode, its reliability and sustainability. On the other hand, this contributes to a more complete development of the exchange capacity of ion exchangers and a more complete use of the regeneration agent. This reduces the amount of ionite loading in the filters and the size of the lmgml. R gv zi WITH THIS uve filters themselves. Therefore, an increase in the number of filters (the smallest number of filters for implementing the proposed method is not less than 6) does not increase the cost of the entire installation. The invention The method of continuous ion-exchange water purification, including a cyclic sequence of durable, clearing, regenerating, and loosening operations on a group of ion-exchange filters, characterized in that, in order to increase the stability of the cleaning mode and to save reagents, the softening and regeneration are carried out in several stages, with the duration of each stage being equal to the duration of washing or loosening, and the beginning of each stage or operation is carried out on all filters of the group of emenno.