Electrochemical Decontamination Methods And Techniques

The electrochemical decontamination method is studied while removing pollution on surface of stainless steel is a main goal. It is found during researching that the conductance of solution, distance between electrodes, and composition determine the efficiency of decontamination and the result of electrolysis. Then a new method of electrochemical decontamination which uses pulse power is developed. Moreover, some elements of equipments which have commissioned for long time are cleaned up by some methods of electrochemical decontamination. The decontamination obtains good result. Basing on these researching results, the equipment of electrochemical decontamination which is consisted with electrobath and cleaning trough. The main results are listed as following.Firstly, there is better efficiency for the electrochemical decontamination than for the ordinary chemical decontamination. The goal of decontamination can be arrived at in short time. In addition, electrolyte has large decontamination capacity. Therefore it can be used in long time so that electrolyte wastage, decontamination cost and waste are reduced. Moreover, electrochemical decontamination can be used to clean up the internal and external surface of elements which there are a kind of special shape.Secondly, it is found that there are good effects when pulsed power is used such as shorter work time, higher current efficiency, lower power consumption, and so on. The main mechanism bases on the characteristic of pulse power of which electrodes are activated and difference is reduced in concentration because of relaxation of current. Shut-off time not only help to recover concentration in anode zone but also bring some advantages such as molecular desorption. In this electrochemistry system, much of electric work is used to overcome resistance of electrolyte and decompose water. Therefore, there is better decontamination effect when pulse power is used. Changing proportion between positive and negative pulse in a proper range can raise decontamination effect. It is the chief reason that the reverse pulse can remove hydrogen and oxygen to reduce passivation to electrodes, which absorb on surface of electrodes. Of course, problems in pulsing electrolysis kinetics need be researchedcontinually.Finally, the electrochemical equipment for decontamination is developed, which can remove pollution on surface of metal. There is an automatic controlling system to adjust electrolyte. There are some main functions in this system such as controlling system power, controlling pH value of electrolyte, controlling conductance of solution, controlling air pump, controlling filter for recycling electrolyte, and so on. It is prove that the electrochemical equipment arrive at the goal of design after running. The decontamination effect is closed to effect in laboratory. It can be used to remove pollution on surface of parts and material of metal. It provides a basis to develop new electrochemical system for decontamination.