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Formulation water is further divided into oral medicine and injection medicine.
Except for raw material medicines, tap water shall be used as the water, and the rest shall be pure water.
1. Problems in the application of reverse osmosis equipment Reverse osmosis desalination is more important than other desalination devices, such as evaporators, electrodialysis, and double beds, and has unique features and advantages. Localization of reverse osmosis is increasingly receiving attention. . With the increase in the application of reverse osmosis technology, the problems that have emerged have become increasingly serious. In recent years, extensive research has been conducted on the application of reverse osmosis water treatment devices. A total of 99 sets of RO water treatment devices from various industries across the country have been collected, of which a full set of 76 sets have been imported from abroad, and some domestically produced and partially introduced devices have been formed together. 13 sets, a full set of equipment are made in 10 sets. After finishing the research, it was found that the normal use rate of the full set of imports was 30%; the normal use rate of some domestically-produced and partially-introduced equipment was 60%; the normal use rate of the full set of domestic products was 10%. The above problems are mainly caused by the following reasons:
1 The complete set of imported equipment is not suitable for China's actual situation due to the difference in raw water quality, lack of technical demonstration and process modification, copying and copying. Therefore, reverse osmosis water must be pretreated according to the different raw water quality to meet the water quality requirements of the equipment.
2 Some enterprises with poor technical capabilities do not understand the rational choice of membrane elements and their quantities in reverse osmosis devices, and the rational arrangement of membrane elements, causing some membrane elements to operate under abnormal conditions.
3 domestic film quality but off. The quality of the membrane directly affects the removal rate of salt and other impurities. Filmtec composite membrane produced by the Dow Chemical Company of the United States has a retention rate of more than 90%.
4 Lax operation and management. When the system is operating, the pressure must be within the acceptable working pressure range of the membrane to prevent over-strength and overload operation, causing mechanical damage to the membrane and lead to leakage. When the reverse osmosis system is operated for a period of time, the sharp decrease in water production, deterioration of the water quality or increase in pressure difference means that the membrane needs to be cleaned. At this time, the machine should be converted to a cleaning state, so that the system can be cleaned by itself and the membrane can be recovered. The function.
2. Technical improvement Mechanical filter design The main reason for the low normal use rate of imported equipment is that the pretreatment equipment does not combine with the poor quality of raw water in China. The backwash of mechanical filters is not complete, and the upper filter cake is agglomerated. SDI (pollution index) Increased, causing fouling of the membrane and affecting system operation. RO devices generally require SDI <4 (each membrane element manufacturer has different requirements for SDI). To achieve the above requirements, the following recommendations are made through research and practice:
(1) Selection of mechanical filter It is recommended to use double-layer filter material filter in combination with raw water quality and equipment materials and fillers in China. From the filter mechanism, it should be large and small, but in fact the mechanical filter is trapped by the finest sand layer on the upper layer, so the top sand is easy to block, block, and the head loss increases rapidly. If granular anthracite is added to the upper layer of sand, it will increase the capacity of contaminants, the operation cycle will be long, and the loss of water head will increase slowly. The application effect is good in practice.
(2) mechanical filter backwash mechanical filter due to the large proportion of the internal loading of quartz sand, recoil is not easy, many systems running is not to ignore the backwash completely, clean this process, the system installed on the recoil devices are reached Without the requirement of backwashing strength, this is a problem for many water treatment equipment manufacturers and engineering companies. After the author's joint research and practice with a processing equipment company, the method of repeated flushing with gas and water, the backwash effect after mechanical filter fouling is very obvious, the sand layer cleaning is very clean, and the performance recovers well. The specific measures are:
1 When designing the backwashing device, the recoil pump and the pipeline must meet the requirements of the backwash volume, and the backwashing strength is 12-15L/(sÂ·m2);
2 Scrub the filter material with compressed air to make the sludge surface of the filter material fall off. Its strength is 18-25L/(sÂ·m2).
(3) Selection of Partial Fillers The internal fillers can be selected from quartz sands of different particle sizes depending on the drainage structure, but the particle size of the uppermost quartz sand should be 0.3 mm. Fill in the top 0.5-1.0MM particle anthracite, the height of not less than 200MM.
Activated Carbon Adsorption The activated carbon adsorber has two main functions:
1Adsorption of some organic substances in water, the adsorption rate is about 60%;
2 Adsorption of residual chlorine in water. For users who directly pump groundwater, the activated carbon can be removed. If the hardness is higher, the water softener is selected. For the surface water, activated carbon must be used because the residual chlorine in the water has a strong oxidizing property and can damage the RO membrane. According to RO The influent water requirement of the system is less than 0.1 MG/L, so activated carbon is used to adsorb residual chlorine. In addition, the removal of residual chlorine from activated carbon is not a simple adsorption process, but a catalytic action occurs on the surface of the activated carbon. Therefore, there is no problem of saturated adsorption of activated carbon, but only carbon is lost.
The selection of coagulant is preceded by the addition of various flocculants and polymer flocculants to remove impurities such as suspended solids and colloids in the water before the mechanical filter. However, if it is not added according to the truth of the water source, not only can it not improve the water quality, but on the contrary, The impurities contained in the drug itself or in the drug substance cause the water to be harmful to the RO membrane. There are many pharmaceutical plants in China that have the above problems in the water treatment system. Therefore, the choice of drugs is very particular about. According to the characteristics of RO membrane:
1 Aggregate should avoid the use of aluminum salts. Aluminium salt flocculants make it easy to produce aluminum glue in the process of agglomeration, and it is not easy to clean after entering the RO surface;
2 Cationic polymer flocculants should not be used. The RO membrane is anionic, and the cationic polymer flocculant is easily combined with the membrane to form a hard-to-clean polymer membrane. If you do not pay attention to the above situation, reducing the membrane life will reduce the weight of some membrane components. At the same time the compatibility between the agents can not be ignored, such as the use of ST polymer flocculant should be used in conjunction with ArgoAF150ul.
Discussion of RO System (1) Importance of Security Filter The main purpose of the security filter is to ensure that RO inlet water does not damage the membrane module. Generally, the filter pore size is 5Î¼m. The exchange filter element is determined according to the differential pressure before and after, and the differential pressure is controlled at 58. .8kPa or less.
Filter time should not be too long, because the filter is easy to grow bacteria, it is recommended to use 14 ~ 15t / (h Â· m2) (m2 filter element filter area.)
(2) The use of scale inhibitors Reverse osmosis membrane fouling can be divided into: biological pollution, suspended solids pollution, chemical pollution, colloidal pollution, bacterial contamination and so on. At present, sodium hexametaphosphate is the most used scale inhibitor in the reverse osmosis system, but sodium hexametaphosphate is easily decomposed into phosphate, which is also a source of bacteria for bacteria. Therefore, improper use can easily cause biological contamination. In addition, sodium hexametaphosphate is not easy to dissolve, and its own fouling also affects the operation of the system. Scale inhibitors also have:
1 can inhibit bacterial growth and extend the cleaning cycle;
2 It can prevent molten iron dissolved and insoluble in raw water from affecting the system operation and causing irreversible membrane fouling.
3 increase the saturation threshold (LSI value of up to 2.5), for most of the original water can not add acid, for a small part of the original water can also reduce the acid dosage, thereby reducing the reverse osmosis CO2;
4 The composition of the drug is stable, it can be stored for a long time and opened for use. In order to ensure the normal operation of the RO system, in addition to selecting the appropriate scale inhibitor type, the amount of dosing should also be calculated based on the raw water quality.
(3) Configuration of large flow flushing Reverse osmosis In the process of water quality separation, the membrane surface contains many contaminants. Since the water separation direction is in 90Â° relation with the direction of the water flow, part of the membrane surface contaminants can be removed by extensive flushing. The original domestic assembly equipment neglected the cleaning device, and the imported equipment was equipped with a cleaning device. At present, some water treatment equipment engineering companies that the author has contacted have all developed the PLC self-controlled large flow flushing system. This set of devices is beneficial to the extension of the service life of RO membranes.
(4) Selection of Chemical Cleaning Solution In normal operation, the RO system only needs to be cleaned 3-4 times a year. Different types of pollution should use different agents. In China, citric acid and EDTA are generally used as the main components, but the cleaning effect is often poor, and the cleaning effect of the imported cleaning solution is obvious.
(5) Design of reverse osmosis device There is a complicated calculation method for RO device design calculation. Currently, foreign film component manufacturers have developed special software, as long as the designer initially determines the solution according to the raw water quality report and the performance of each membrane component, and then Raw water quality is entered into the computer, and the feasibility of the preliminary scheme is verified by the program software. If this is not possible, then a warning is issued and what part of the design is unreasonable. In addition, the designer should pay attention to the various protection measures that the design should be equipped with according to the requirements in the user manual of the membrane element.
Mixed bed UV sterilizer and membrane filter selection of mixed bed is the ultimate means to improve water quality, UV sterilizer can kill bacteria in the water, and then through the membrane filter to remove bacteria corpses, these sets of designs can be used conventional products, in this No narration.
From a simple cooking tool, gradually evolved into both use and artistic value of household items.The classification and function of Kitchen Knives are more and more detailed, from the era of a Kitchen Knife fighting the world, developed into today's special combination of knives.We can provide customers all over the world with the best quality and colorful Plastic+TPR handle paring knives,also we can customize different paring knives according to the living habits of different countries.
Stainless Steel Paring Knife Sets,Tpr Handle Paring Knife,Tpr Knife,Tpr+Pp Handle Paring Knife
HONG TAO KITCHEN INDUSTRY CO.,LTD , https://www.htkitchenware.com