Regarding the issue of one large turbine or hydrogen compressor corresponding to two electrolysis systems
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I have a question: What problems might arise if a single high-capacity turbine or hydrogen compressor is used to serve two electrolysis systems? There are currently two separate 100,000 tons per year caustic soda production units, with both the electrolysis and hydrochlorine treatment processes operating as independent systems. There are proposals to use a single large turbine or hydrogen compressor to serve these two systems, in other words, one machine to drive both systems. I’m not sure what problems might arise during runtime with this configuration
Several aspects are mainly considered: 1. The interlock settings of the SIS system； 2. Delays during the closing process of various shut-off valves in an accident scenario ； 3. Adjustment speed and accuracy of each control valve under accident conditions ； 4. Level of proficiency of the operators ； Based on the operational conditions of our company, the 1-to-2 configuration is not recommended. There are too many potential risks in every aspect
Could you please explain the operation of your 1-to-2 system, as well as any problems that have occurred or may occur?
The SIS system requires that the rectifier trip interlock shuts down the chlorine compressors; in the case of a 1-to-2 configuration, two sets of such rectifier trip interlocks are needed to shut down the chlorine compressors； If one set of rectifiers shuts down, the hydrogen-chlorine pressure difference in the other set cannot be maintained, which can easily lead to the shutdown of the second set of equipment as well ；
Many of them are capable of handling two tasks at once, with no problems.
Do your hydrogen compressors use turbines or pistons?
A Siemens 3K chlorine compressor can handle two electrolysis units without any problem. There are a few points to keep in mind: 1. The chlorine suction for Units A and B should be equipped with separate control valves/emergency chlorine release valves, to prevent imbalance between the two units – one drawing too much chlorine while the other draws too little. Normally, automatic control is achieved through the large reflux flow in the chlorine treatment system and the guide vanes at the inlet of the chlorine compressor. 2. Interlocks associated with the electrolyzer and the setup of the SIS, as well as the operational requirements for activating and deactivating these interlocks during startup. 3. Settings for the operations and procedures of DCS operators. 4. Install a tee connection valve at the inlet of this compressor; it’s necessary for future use... Otherwise, it will limit production capacity, and it will be difficult to operate the compressor in summer, as it won’t be able to reach its full load... This has been done for 4 years now