Purification engineering of purified water pipeline related introduction

1. pipeline: piping material should choose non-toxic engineering plastics or stainless steel. Stainless steel material is characterized by:
A. is chemically inert after passivation;
B. is easy to disinfect;
C. has a wide range of operating temperature.
Diaphragm to the diaphragm to the media and other components of the valve isolation, and make its channel tight, simple, smooth, easy to pollution, cleaning channels, and replacement of the diaphragm are more convenient, and therefore often used for water engineering.
2., pipe connection and pressure test connector: stainless steel piping should be hot melt argon arc welding, the inner wall to be smooth, should check the quality of welding, recording the number of welding, and do X light shooting. Because the pipeline in the technology to take the first film, laminated film form, commonly used automatic argon arc melting welder, welding equipment to determine the control parameters according to the manual, such as the current size, frequency, and then the welding parameters of welding joints, before installation film (such as unconditional delivery, Waipai tablets) as to meet the requirements, can be controlled in the welding parameters in after installation, to ensure smooth weld after welding, with deionized water pressure test, the test pressure is 1.5 times the working pressure, no leakage.
3 pipeline cleaning, passivation, disinfection, stainless steel pipe (cleaning, passivation, disinfection) can be divided into purified water cycle pre washing, cleaning, water purification cycle of alkali cleaning, passivation, purified water, rinse again, pure steam discharge disinfection steps.
A. purified water cycle pre rinse: prepare a liquid storage tank and a water pump, and pipeline passivation into a circulation path, inject enough at room temperature in the liquid storage tank in purified water, circulating water pump to open the drain valve, after 15min, while circulating emissions, best to install a flowmeter;
B. lye cleaning: prepare sodium hydroxide chemical pure reagent, add hot water (temperature is not less than 70 DEG C), prepare 1% (volume concentration) lye, use pump for cycle, time is not less than 30min, then discharge;
C. flushing: adding purified water to the storage tank, starting the water pump, opening the drain valve and discharging until the resistivity of each outlet water is consistent with the resistivity of the tank water, and the discharge time is at least 30min;
D. purification:
(a) 8% acid solution was prepared with purified water and chemically pure nitric acid, which was discharged at 60min at 49-50 DEG c;
(b) or with 3% hydrofluoric acid, 20% nitric acid and 77% water purification solution, solution temperature of 25-35 degrees, and then discharged 1020min circulation treatment;
E. initial flushing: rinse at normal temperature, not less than 5min;
F. final rinse: rinse again until the resistivity of the purified water is consistent with the inlet and outlet;
G. pure steam sterilization: clean steam is passed into the entire stainless steel piping system, and at least 15min is washed at each point of use. The cleaning, passivation and disinfection processes and their parameters shall be recorded.