A switching system of an EDR water purifier has a first inlet end, a second inlet end, a first three-way solenoid valve, a second three-way solenoid valve, a third three-way solenoid valve, a fourth three-way solenoid valve, an EDR membrane stack, a first outlet end, and a second outlet end. The EDR membrane stack has a first inlet port, a second inlet port, a first outlet port, a second outlet port, a first electrode, and a second electrode. Each three-way solenoid valve has an inlet opening, a first outlet opening, and a second outlet opening. Each outlet opening of each three-way solenoid valve can be turned open or closed for switching two water routes passing the EDR membrane stack. Therefore, speed of forming limescale decreases, lifespan of the EDR membrane stack is prolonged, and water-purifying efficiency is improved.

A switching system has two inlet ends, two outlet ends, and an EDR membrane stack. Each inlet end and each outlet end are connected to both a primary branch and a secondary branch. Solenoid valves are mounted on each primary branch and each secondary branch to switch between opening and closing. The EDR membrane stack has two inlets, two outlets, and two electrodes. One inlet is connected to the primary branch of the two inlet ends while the other is connected to the secondary branch of the two inlet ends. One outlet is connected to the primary branch of the two outlet ends while the other is connected to the secondary branch of the two outlet ends. The polarity of the two electrodes is interchangeable to realize the reverse polarity of the electrodes. The two water flows that pass through the EDR membrane stack are interchangeable.

A switching system has two inlet ends, two outlet ends, and an EDR membrane stack. Each inlet end and each outlet end are connected to both a primary branch and a secondary branch. Solenoid valves are mounted on each primary branch and each secondary branch to switch between opening and closing. The EDR membrane stack has two inlets, two outlets, and two electrodes. One inlet is connected to the primary branch of the two inlet ends while the other is connected to the secondary branch of the two inlet ends. One outlet is connected to the primary branch of the two outlet ends while the other is connected to the secondary branch of the two outlet ends. The polarity of the two electrodes is interchangeable to realize the reverse polarity of the electrodes. The two water flows that pass through the EDR membrane stack are interchangeable.

A switching system for an EDR water purifier has a first raw-water inlet end, a second raw-water inlet end, two four-way solenoid valves, an EDR membrane stack, a freshwater outlet end, and a wastewater outlet end. Each four-way solenoid valve has a first inlet end, a second inlet end, a first outlet end, and a second outlet end. The first inlet end of each four-way solenoid valve can communicate with one of the first outlet end and the second outlet end of the same four-way solenoid valve, and the second inlet end of the same four-way solenoid valve can communicate with the other one of the first outlet end and the second outlet end, to execute water-route switching. By switching two water routes passing through the EDR membrane stack, forming of limescale is alleviated, lifespan of the EDR membrane stack is extended, and water-purifying efficiency is improved.

A switching system for an EDR water purifier has a first raw-water inlet end, a second raw-water inlet end, two four-way solenoid valves, an EDR membrane stack, a freshwater outlet end, and a wastewater outlet end. Each four-way solenoid valve has a first inlet end, a second inlet end, a first outlet end, and a second outlet end. The first inlet end of each four-way solenoid valve can communicate with one of the first outlet end and the second outlet end of the same four-way solenoid valve, and the second inlet end of the same four-way solenoid valve can communicate with the other one of the first outlet end and the second outlet end, to execute water-route switching. By switching two water routes passing through the EDR membrane stack, forming of limescale is alleviated, lifespan of the EDR membrane stack is extended, and water-purifying efficiency is improved.

An ion separator according to an embodiment of the present invention includes: a first electrode buffer channel and a second electrode buffer channel; a main channel that connects between the first electrode buffer channel and the second buffer channel; a first ion exchange membrane positioned between the first electrode buffer channel and the main channel; a porous second ion exchange membrane that is provide across the main channel and contains pores of different sizes; a first electrode electrically connected to the main channel with the first electrode buffer channel in between; and a second electrode electrically connected to the main channel with the second electrode buffer channel in between, wherein the second ion exchange membrane may be inserted into the main channel while being inclined toward a fluid flowing through the main channel.

In this disclosure, a process of recycling acid, base and the salt reagents required in the Li recovery process is introduced. A membrane electrolysis cell which incorporates an oxygen depolarized cathode is implemented to generate the required chemicals onsite. The system can utilize a portion of the salar brine or other lithium-containing brine or solid waste to generate hydrochloric or sulfuric acid, sodium hydroxide and carbonate salts. Simultaneous generation of acid and base allows for taking advantage of both chemicals during the conventional Li recovery from brines and mineral rocks. The desalinated water can also be used for the washing steps on the recovery process or returned into the evaporation ponds. The method also can be used for the direct conversion of lithium salts to the high value LiOH product. The method does not produce any solid effluent which makes it easy-to-adopt for use in existing industrial Li recovery plants.

In this disclosure, a process of recycling acid, base and the salt reagents required in the Li recovery process is introduced. A membrane electrolysis cell which incorporates an oxygen depolarized cathode is implemented to generate the required chemicals onsite. The system can utilize a portion of the salar brine or other lithium-containing brine or solid waste to generate hydrochloric or sulfuric acid, sodium hydroxide and carbonate salts. Simultaneous generation of acid and base allows for taking advantage of both chemicals during the conventional Li recovery from brines and mineral rocks. The desalinated water can also be used for the washing steps on the recovery process or returned into the evaporation ponds. The method also can be used for the direct conversion of lithium salts to the high value LiOH product. The method does not produce any solid effluent which makes it easy-to-adopt for use in existing industrial Li recovery plants.

A bipolar membrane in which a cation-exchange membrane and an anion-exchange membrane are joined to each other, wherein a leakage ratio of gluconic acid at 60° C. is not more than 1.0%, and the cation-exchange membrane is supported by a polyolefin reinforcing member and, further, contains a polyvinyl chloride.

A bipolar membrane in which a cation-exchange membrane and an anion-exchange membrane are joined to each other, wherein a leakage ratio of gluconic acid at 60° C. is not more than 1.0%, and the cation-exchange membrane is supported by a polyolefin reinforcing member and, further, contains a polyvinyl chloride.