How should wastewater be treated during the commissioning of a chemical plant?
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According to the commissioning specifications, the sewage treatment plant must align with the schedule of the utility systems, and its commissioning must be completed in advance to prepare for receiving sewage. However, the schedule for the wastewater treatment plant at our factory is at the end; during the initial testing phase, the wastewater could only be accepted rather than treated. I would like to ask: during the commissioning of a chemical plant, water-based and oil-based control systems are used. How should these wastewater and waste oils be handled? Waste oil probably needs to be recycled, but what about the wastewater? Should it be discharged directly into the rainwater system?
Direct discharge is definitely not an option; if the quantity is small, it can be placed in containers for further processing, or first poured into a tank
Putting aside the wastewater generated in the workshop due to water-related processes, that wastewater is basically just rust; it might be possible to discharge it directly after it settles； For the treatment of that circulating water system, physical cleaning, chemical cleaning, and pre-coating are required; in total, this involves more than 5,000 cubic meters of liquid – more than the volume of our accident tank – and all of this liquid has had chemicals added to it.
If it can be discharged directly, do so; if not, it can be processed in a tank before being discharged!
As for wastewater, it can’t be discharged directly along with rainwater; it needs to be collected and sent to a wastewater treatment plant
Is the wastewater after testing warm? The precipitate can be recovered and reused; it can be used as fire-fighting water or circulating water.
The water quality resulting from water-driven operation should not be too poor; it’s similar to what happens when rain washes the ground and equipment, so it should be possible to drain rainwater. However, treating wastewater is definitely the best option!
If the wastewater treatment plant isn’t yet in operation, you start trial production anyway – this is really strange. How is it possible to pass the environmental compliance inspections in such a situation? ? ? ? ? ? ? ? ? ? ? ?
There were issues with the initial planning; the sewage treatment plant should have been the first facility to come online. There are many types of wastewater generated during the initial testing phase. High-concentration oily wastewater can be pumped into the emergency tank first, and later mixed with low-concentration wastewater before being treated. The flushing water used to flush the pipelines in the initial stage is discharged directly, while the water used for acid cleaning and pre-coating in the circulation process does not meet the discharge standards and must be recycled. I really don’t know what your managers are thinking – it takes around two months just for the initial cultivation of the bacteria. The high-concentration wastewater during the trial operation phase places a great strain on these bacteria, making it very difficult to achieve satisfactory results in just one attempt. I guess you don’t have facilities to store wastewater for several months either; think about whether you can get other factories to handle it on your behalf
A reminder: the water used for acid washing and pre-coating in the circulating water system should not be directly fed into the biological treatment process, as it has a very high conductivity, is acidic, and contains both oxidizing and non-oxidizing disinfectants. We made this mistake before; it took us almost 2 months to revive the bacteria: lol
No production was carried out. During the joint commissioning, the pipes needed to be flushed with water, and there was also wastewater from the system’s water circulation processes. Were there any procedures required at that time?