The working principle and application of boiler softened water treatment equipment

　　The fully automatic soft water equipment control system technology is formed, easy to operate and reliable in operation. Whether a boiler can operate economically or not, water quality treatment is of great significance. The boiler softening water device is a kind of pre-treatment device for removing hardness from raw water launched in response to boiler scaling. It removes calcium and magnesium ions from the raw water, preventing scale formation inside the boiler, improving the heat exchange utilization rate of the boiler, and ensuring the stable operation of the boiler. This article provides you with a detailed introduction to the working principle and application of boiler softened water treatment equipment.

　　The hardness of water is mainly formed and represented by calcium and magnesium. The principle of sodium ion exchange softening treatment is to pass the raw water through a sodium-type anodeIon exchange resinThe hardness component in waterCa2+,Mg2+In the resinNa+Exchange with each other, thereby adsorbing substances in waterCa2+,Mg2+Soften the water.

　　The chemical equation for converting hard water to softened water:

　　Calcium removalCaCO3+2NaCl=CaCl2+Na2CO3;

　　Removal of magnesiumMgCO3+2NaCl=MgCl2+Na2CO3;

　　3,Boiler water softening equipmentControl valve type

　　<1>Semi-automatic(Manual)Control valve;

　　<2>Fully automatic flow control valve;

　　<3>Fully automatic time-type control valve;

　　4BoilerSoftened water equipmentAnalysis of the reasons for excessive hardness of soft water:

　　1)The sampling port test of the soft water equipment was qualified, but the water hardness in the soft water tank exceeded the standard. The reasons for this phenomenon are as follows:

　　AThe regeneration cycle is set too high or the flowmeter malfunctions cause inaccurate measurement, resulting in the resin not being regenerated in time when it should be regenerated, and thus the excess water is injected into the soft water tank.

　　BThe forward wash time is too short, causing some of the waste brine that should have been washed away during the forward wash to be carried into the soft water tank.

　　CUnstable water pressure in the feed water can lead to insufficient water replenishment in the salt tank, insufficient salt absorption, and inadequate forward washing. Any of these factors can cause the hardness of the effluent after regeneration to exceed the standard, affecting the water quality of the soft water tank.

　　DWhen there was very little salt in the salt tank, it was not added in time, resulting in poor regeneration effect on a certain occasions.

　　EImproper operation led to the closure of the feed water valve during a certain regeneration process.

　　Any of the above mistakes can cause a large amount of excessive water to be injected into the soft water tank in a short period of time. It requires qualified soft water to dilute the excessive water for a long time before the water in the soft water tank can meet the standards again.

　　2)Multiple tests were conducted at the sampling port of the soft water equipment, all of which were found to be substandard. This situation was discussed separately as the initial water test hardness exceeding the standard for newly installed soft water equipment and the hardness exceeding the standard for in-use soft water equipment.

　　AThe reasons for the hardness of the newly installed soft water equipment exceeding the standard during the first water test:

　　a At the junction of the pipe and the control valveOIf the conical sealing ring has not formed a seal, the following should be inspected at this time:

　　·Whether the length of the pipe is sufficient and whether the outer diameter meets the requirements;

　　·Did you forget to install it?OShaped sealing ring

　　·OWhether the conical sealing ring is damaged;

　　b The pipe is damaged and has cracks.

　　c Water supplyTDSThe ratio of the value to the height of the resin layer is too large.

　　d Water supplyTDSThe ratio of the value to the resin exchange capacity is too large.

　　e The inlet and outlet are connected in reverse.

　　B The reasons for the excessive hardness of soft water in use by soft water equipment:

　　a Water supplyTDSThe ratio of the value to the height of the resin layer or the resin exchange capacity is too large. Compared with the initial water test of the new resin, the water supply is treated with a soft water equipmentTDSThe value requirements are stricter when the height of the resin layer is1.5The total hardness of the meter is13mmol/LWater supplyTDSvalue≧900mg/LWhen doing so, ensure the hardness of the soft water≤0.03mmol/LIt will be rather difficult.

　　b The reduction of resin exchange capacity caused by resin poisoning and aging. The excessive hardness of soft water caused by this reason is a gradual process, not a sudden and obvious over-limit.

　　c There is too little salt in the salt tank. When the water level in the salt tank is normal but the height of the salt is less than that of the water1/3At that time, the brine absorbed in the middle and later stages of the brine absorption process is very likely to be unsaturated, resulting in the brine concentration diluted by the jet injector being lower than the regeneration requirements, which affects the regeneration effect.

　　d The total water volume in the salt tank is too low. Our experience is that in the resin tank, every100LThe amount of water required in the salt tank for resin is approximately35-40LIf the standard is too low, it will lead to insufficient regeneration.

　　e The salt water inhalation is too slow. Within the normal time, sufficient salt water cannot be inhaled. The reasons are as follows:

　　·The water supply pressure is too low.

　　·The upper and lower water distribution areas are severely clogged with silt and other debris.

　　·Poor drainage of wastewater caused by deformation or bending of the wastewater hose;

　　·There are too many impurities in the resin layer.

　　·There is a leakage point on the salt suction pipe, causing air to be sucked in.

　　·There is a foreign object in the jet injector.

　　·The air check valve malfunctioned, closed prematurely or was blocked.

　　·The selection of the jet injector is too small.

　　3)There is a large amount of gas in the resin tank. This gas may come from the presence of gas in the feed water or the air check valve not closing tightly during the slow wash process.

　　g No large grains of non-iodized salt were used.

　　h Internal leakage of the control valve: When there is internal leakage of a general control valve, it often occurs that both the soft water port and the waste water port discharge water simultaneously. However, for64Dor74AIn this series, internal leakage may occur through small holes on the ceramic moving plate. If it is this kind of internal leakage, qualified soft water can be detected at the wastewater outlet when in the positive flushing position, but the hardness of the soft water exceeds the standard when it is transferred to the operating position.

　　Small boiler(Evaporation volume＜20t/h)The make-up water mainly consists of chemical water treatment outside the boiler - that is, what we often call softened water, according toGB1576-2001Water quality standards for industrial boilersStipulated, the maximum evaporation capacity≤2t/hAnd the rated steam pressure≤1.0MPaThe steam boiler and steam-water dual-purpose boiler as well as their rated power≤4.2MWFor non-pipe-mounted pressure-bearing hot water boilers and atmospheric hot water boilers, in-boiler chemical treatment can be adopted. Despite the above regulations, based on our experience, in the two types of situations where in-boiler chemical treatment can be used, we still strongly recommend using softened water as boiler feed water for the following reasons:

　　(one)The inspection indicators for softened water are single, and the inspection methods are simple. The water treatment effect can be detected at any time and in real time, allowing for a clear understanding. However, the water treatment effect of the in-pot dosing method is not easy to test. In practice, the anti-scaling effect is often visually inspected by opening the manhole and handhole after the boiler has been running for a period of time, which leads to a lag in the testing methods.

　　(two)Softened water treatment aims to remove calcium and magnesium from water, and the treatment methods for water of different properties are basically the same. Strictly speaking, different methods of adding chemicals in the pot have different anti-scaling mechanisms. For different water qualities, the formula of the chemicals should be adjusted accordingly. However, in practice, it is often encountered that the same formula is applied to multiple water qualities, which leads to many cases of poor effects.

　　(three)For hot water boilers, if softened water is not used, serious consequences may occur in some cases. In practice, due to reasons such as boiler type design, we have found that a large number of hot water boilers have local vaporization problems in the high-temperature zone. In the water pipe sections where vaporization is severe, even excessive scale causes local blockage, resulting in pipe burst. Therefore, we suggest that hot water boilers should not only be equipped with water softening devices, but also the standards for boiler feed water should be relatively highGB1576-2001As stipulated0.6mmol/LMore strictly, the standards implemented within our enterprise are0.1mmol/LIt has achieved good results in the application of many hot water boilers.

　　(four)The emergence of fully automatic water softening equipment has reduced the requirements for the operators of water softening equipment, enabling many units without full-time water treatment and laboratory personnel to still use softened water well as boiler feed water, especiallyTMFThe successful application of the system water softening equipment has significantly reduced the production cost of fully automatic water softening equipment, and has greatly decreased the one-time investment when the boiler is equipped with fully automatic water softening equipment. Truly makeSoftened water treatment technologyIt has extremely obvious advantages compared with other water treatment methods.