Regarding Asahi Kasei electrolyzer WM2 pure water

It must have been on all along; generally, other processes also use water, and the catholyte requires it as well

The key is to look at the specific process pipelines for WM1 and WM2; if the washing tanks are supplied separately, operations can be stopped.

WM2 denotes intermittent water supply; it is used only when cleaning the electrolytic cell, and is not activated under normal conditions.

To be honest, if the pipeline flow rate is sufficient, there’s no need to set up two pure water systems – it’s a waste of piping material! In the first phase of construction, our factory used two sets of WM1 and WM2. During the second phase, modifications were made: connection valves were added between WM1 and WM2. WM2 is used for intermittent water consumption, and it’s hardly ever needed in normal operations! A single pure water pipe can be shared!

Reply to 5# vipchinazhou: The amount of water required for washing the electrolyzer cells when everything is shut down is still quite substantial, and this requirement has to be met in a short time. If only continuous water from the pipeline network is used, it will be difficult to meet the demand, and it will also affect water usage in other areas. It is best to have a dedicated pure water tank in the electrolysis area, supplied by two pumps—one continuous and one intermittent.

We supply Line 2 separately; we cannot share pumps with Line 1 as the fluctuations are too large. It is activated only when it is necessary to clean the electrolyzer

Reply 6# JSLIU*ANG There’s some truth to that! But the pure water pipe WM1 we used in the first phase with a capacity of 70,000 tons remains effective even after the capacity is expanded to 180,000 tons! I think as long as the pipeline flux is sufficient and the pressure on the official website is maintained, it shouldn’t be a problem! Moreover, it’s impossible to drain and clean the tanks all at once when the electrolysis cells are completely shut down; due to factors such as the available manpower and the volume of water to be drained, we arrange the tasks to be carried out at different times! Generally, 4 electrolyzers are grouped together in one batch, and that’s sufficient for now! Thank you for your reply!

This post was last edited by pzhhuagong on 2010-6-26 01:11. It is recommended to keep them separate; the design for Beihua Machinery is such that WM1 is a dedicated pipeline for pure water used in electrolysis processes； WM2 represents pure water used intermittently throughout the plant: There is surely a reason for this separation, which is to minimize fluctuations in pressure or flow rate resulting from continuous use of pure water. For example, pure water is used when adding alkalis, when adding acids to tanks, and in dechlorination vacuum pumps; during normal operation, it is required that the flow rate remain stable ； So in WM1 ； (Circulation pumps for dechlorination, water used for the mechanical seals of brine pumps, etc. are also under WM1.) For example, situations such as high-volume water consumption in other processes like brine membrane treatment, resin regeneration, tank washing, and shutdown replacement are all handled by WM2. If the pipelines are connected in parallel, it is not possible to ensure a stable water supply for the electrolyzers when there is high-volume water demand elsewhere. In cases where one cell is operating while another is suddenly shut down, water must be added to dilute the brine. When one cell is running while other cells are being used for membrane wetting or tank cleaning, or when resin towers need to be regenerated or require high-volume backwashing, or after high-purity acid is used to treat the circulation tanks, pure water must be replenished promptly (since there are circulation tanks acting as intermediaries, this falls under WM2). Under such circumstances, the pressure of the water supply for continuous operation experiences significant fluctuations. The pump that provides WM2 also needs to run continuously, because you cannot know with certainty when there will be a sudden large demand for water, such as in the event of an emergency shutdown

Pure water 1 provides continuous supply, while pure water 2 offers intermittent supply. As mentioned above, another thing to consider is whether the pump for pure water 2 can be modified so that it starts automatically in case of a sudden shutdown. Although this isn’t currently used in Asahi Kasei’s electrolyzer processes, with all the automatic instruments and valves used in ion-exchange membrane chlor-alkali production, it should be possible to modify the pump so that it starts automatically