Principle and Maintenance of RO_SPC Series Biochemical Ultrapure Water Machine

RO-SPC系列生化超纯水机,其控制系统采用单片计算机控制,功能多,操作简单,可靠性高,纯水机主要部件如高压泵、反渗透膜、电磁阀、调节阀等均采用原装进口部件,性能稳定,使用寿命长。

1水机的工作原理

RO-SPC系列超纯水机的工作原理按仪器用水标准,分为四个部分。第一部分为预处理:进入纯水机的水先经过5μm的PP滤芯,去掉水中的机械杂质,如泥沙、铁锈、悬浮物等;再经过活性炭滤芯,去掉水中的胶体、大分子有机物、余氯、异味等。第二部分为反渗透:经过预处理的水,由高压泵进入反渗透膜,在高压泵压力的作用下,由于反渗透膜的半透性,水中各种离子、细菌、病毒、残余有机物、胶体被截留,通过浓水排放,去除率达99%以上;透过反渗透膜的淡水,其电导率一般小于20us/cm,但仍然达不到分析仪器用水电导率要求,还需进一步去离子。第三部分为混床树脂去离子:反渗透出来的淡水进入多级串联的混床树脂滤芯,由于深层离子交换反应的进行,有效去除水中的阴、阳离子,得到18.3～1M.cm.25℃的超纯水。第四部分为膜过滤:为了满足分析仪器颗粒度的要求,避免混床树脂滤芯在运行过程中,树脂颗粒破碎,由纯水箱进入分析仪器管路堵塞电磁阀,在混床树脂滤芯之后,增设了微孔过滤器。

2水机工作状态

2.1主机控制面板上低水位指示灯、冲洗指示灯亮;同时主机内浓水电磁阀打开,高压泵开始工作,进入反渗透膜的物理清洗过程。经过冲洗t1(冲洗时间:0～300s可调)时间后,冲洗指示灯灭,浓水电磁阀关闭,纯水机进入制水状态,流量累计器开始计数,制水指示灯亮,此时顺时针方向慢慢调整调节阀,使主机出口压力表指示值为0.7MPa～0.9MPa(调节好以后,再开机时或使用中不需经常调整)。此后,超纯水机进入全自动工作状态,无需用户进行任何操作。

2.2 During work, if the water level of the external pure Water Tank reaches the predetermined high water level, the high water level indicator light on the control panel of the main engine is on, the high pressure pump stops working, the water inlet solenoid valve is closed, the water control and low water level indicators are off, and the flow rate The accumulator stops counting and stores the data until the water level is low and then automatically starts water production.

If the inlet water pressure is lower than the required value range, after t2 (undervoltage delay time: adjustable from 1 to 60s), the undervoltage indicator light will be on, and at the same time, the main engine will stop flushing or water production, and will turn on at the set t3 (undervoltage delay time: 1-60s adjustable). Checking time: 0~300s (adjustable), automatically monitor the water inlet pressure within the time, and re-enter the flushing or water production state when the water pressure meets the requirements.

2.3 In the process of water production, online monitoring of ultrapure water and reverse osmosis water quality. If the resistivity of the ultrapure water is lower than the required value of water used by the analytical instrument, and the duration exceeds t4 (resistivity monitoring time: adjustable from 0 to 30 minutes), the host will give an audible and visual alarm.

2.4 The flow accumulator does not count when it is not producing water.

3 Cleaning and disinfection of reverse osmosis membrane

3.1 Necessity of cleaning

Under normal operating conditions, the reverse osmosis membrane may be polluted by inorganic substances, colloids, microorganisms, metal oxides, etc., and these substances are deposited on the membrane surface, which will cause a decrease in water production or desalination rate of the reverse osmosis membrane. Therefore, in order to restore Good water permeability and desalination performance require chemical cleaning of the membrane.

3.2 Cleaning conditions

Where one of the following conditions is met, the membrane element needs to be cleaned :

(1) The normal permeate flow rate drops by 10%;

(2) The salt content of the fresh water coming out of the reverse osmosis membrane ( monitored by the conductivity meter) has increased significantly;

3.3 Cleaning method

The cleaning method is to prepare and remove inorganic

Chemical liquid of chemical or organic matter, circulate the chemical liquid between the tank and the reverse osmosis water machine for 30 minutes and keep it for two hours. Rinse off with chemical liquid. The commonly used chemical liquid for removing inorganic matter is 2% citric acid, and the pH value is adjusted to 2.5 to 3.5 with ammonia solution; the commonly used chemical liquid for removing organic matter is 2% sodium hydroxide, and the pH value is adjusted to 10 with ammonia solution ~12; Use 0.5%~1% formaldehyde solution to remove microorganisms and bacteria.