Standards for boiler water

You only mentioned it is used in chemical production; you didn’t specify which process, so it’s difficult for us to give suggestions. Please be more detailed!

Standard time for boiler water: November 2, 2007. More information on “pipes”. Huanqi (Taicang) Plastic Industry Co., Ltd. Guangzhou Branch possesses manufacturing technologies for various plastic valves, pipes, pipe fittings, and other piping equipment. 1. Scope This standard specifies the water quality requirements for industrial boilers during operation. This standard applies to fixed steam boilers and steam-water dual-purpose boilers that use water as the working medium, with a rated outlet steam pressure of 2.5 MPa or less. It also applies to fixed pressurized hot water boilers and atmospheric pressure hot water boilers that use water as the working medium. II. Water Quality Standards 1. For feed water in steam boilers and dual-purpose steam and water boilers, external chemical water treatment is generally required, and the water quality must meet the specifications in Table 1. Table 1: Parameter; Feed Water; Boiler Water. Rated Steam Pressure, MPa: ≤1.0, >1.0, >1.6; ≤1.0, >1.0, >1.6, ≤1.6, ≤2.5, ≤1.6, ≤2.5. Suspended Solids, mg/L: ≤5, ≤5, ≤5. Total Hardness, mmol/L1): ≤0.03, ≤0.03, ≤0.03. Total Alkalinity, mmol/L2): Without superheater: 6–26, 6–24, 6–16; With superheater: ≤14, ≤12. pH (25°C): ≥7, ≥7, ≥7; 10–12, 10–12, 10–12. Dissolved Oxygen, mg/L3): ≤0.1, ≤0.1, ≤0.05. Dissolved Solids, mg/L4): Without superheater: <4000, <3500, <3000; With superheater: <3000, <2500. SO2-3, mg/L4): 10–30, 10–30. PO3-4, mg/L: 10–30, 10–30. Relative Alkalinity (Free NaOH/Dissolved Solids)5): <0.2, <0.2. Oil Content, mg/L: ≤2, ≤2, ≤2. Iron Content, mg/L6): ≤0.3, ≤0.3, ≤0.3. **Approved by the Quality and Technical Supervision Bureau on January 10, 2001; Implemented on October 1, 2001. 1) The basic unit for hardness in mmol/L is c(1/2Ca2+, 1/2Mg2+); the same applies hereafter. 2) The basic units for alkalinity in mmol/L are c(OH-), 1/2CO2-3, and HCO3-, the same applies hereafter. For boilers that have low requirements regarding steam quality and do not have superheaters, the upper limit for the alkalinity value can be appropriately increased, subject to approval from the local boiler and pressure vessel safety supervision authority by the user entity. 3) Deoxidization is required when the rated evaporation capacity of the boiler is 6 t/h or more. For boilers with a rated evaporation capacity of less than 6 t/h, if local corrosion is detected, deoxidization measures should be taken for the feedwater. The oxygen content in the feedwater supplied to turbines should be less than or equal to 0.05 mg/L. 4) If it is difficult to determine the dissolved solids, conductivity or chloride (Cl-) levels can be used as indirect indicators for control; however, the ratio between dissolved solids and conductivity, or between dissolved solids and chloride (Cl-), must be determined through experimentation. This ??ratio should also be re-evaluated and adjusted regularly. 5) The relative alkalinity of fully welded structure boilers can be left uncontrolled. 6) Only for fuel and gas boilers. 2. Steam boilers and combined steam and water boilers with a rated evaporation capacity of 2 t/h or less, and a rated steam pressure of 1.0 MPa or less (provided that there are no special requirements regarding the quality of steam and water) can also employ chemical treatment inside the boiler. However, strict supervision must be exercised over scaling, corrosion, and water quality in the boiler; proper dosing, sludge removal, and cleaning procedures must be carried out, and the water quality must meet the requirements specified in Table 2. Table 2: Parameters for feed water of water supply boilers – Suspended solids, mg/L: ≤20; Total hardness, mmol/l: ≤4; Total alkalinity, mmol/l: 8–26; pH (at 25°C): ≥7–10; Dissolved solids, mg/L: <5000. For pressure-rated hot water boilers, external water treatment is required. For non-frame-type pressure-rated hot water boilers with a rated power of 4.2 MW or less, as well as atmospheric-pressure hot water boilers, internal chemical treatment can be used; however, close monitoring of scaling, corrosion, and water quality is necessary, and proper chemical treatment must be carried out, with the water quality meeting the requirements specified in Table 3. Table 3 Items: Chemical treatment added to the boiler water, External chemical treatment; Feed water to boiler, Water supply to boiler; Water suspended solids, mg/L ≤20 ≤5; Total hardness, mmol/L ≤6 ≤0.6; pH (25°C) 1) ≥7 10–12 ≥7; Dissolved oxygen, mg/L 2) ≤0.1; Oil content, mg/L ≤2 ≤2. 1)? The pH value of the boiler water is controlled between 10 and 12 by adding chemicals. 2)? The feed water for pressure hot water boilers with a rated power of 4.2 MW or more should be deoxygenated; the feed water for pressure hot water boilers with a rated power of less than 4.2 MW and for atmospheric pressure hot water boilers should also be deoxygenated as much as possible. 4. For DC (through-flow) boiler feedwater, external chemical water treatment shall be employed, and the water quality shall comply with the standards specified in Table 1 for a rated steam pressure of greater than 1.6 Mpa and less than or equal to 2.5 Mpa. 5. The water quality parameters for waste heat boilers and electric heating boilers shall meet the requirements of boilers of the same type and with the same parameters. 6. The water quality testing methods shall be carried out in accordance with Appendix A (the appendix to the standards)

Oh, I’ve learned it. Thank you so much to the kind person upstairs for their help