Slag treatment process flow for large-scale gasification units

The treatment of slag water involves sending it to a vacuum flasher, where the gases dissolved in the water are removed by creating a vacuum. The water is then sent to a clarification tank, where fine ash is removed through sedimentation, and the water is reused

Thank you for the explanation from the second floor; could you be more specific?

The primary treatment process for typical wastewater at SCGP is described as follows: 1. Stripping section – The wastewater sent to this unit for stripping treatment mainly consists of the following three streams: The wastewater discharged from the washing section, after pressure reduction through a loss tube, enters feed tank A of the stripping tower, where dissolved CO2 and other toxic gases are vaporized. The fine slag slurry discharged from the slag pool cooling circulating water circuit is, depending on its flow rate, mixed with hydrochloric acid in proportion and then sent to feed tank B, where the outlet pH is controlled at around 6.5 to prevent the formation of CaCO3 precipitates when this relatively low-temperature slurry mixes with the relatively high-temperature materials present there. The collected liquid from the emission system is pumped in batches into feed tank B via an submersible pump. The slurry from the feed tank is pumped by a feed pump in the stripper to the acidic slurry stripper. Low-pressure steam from the lower part of the tower is used for stripping. The gas from the top of the stripper and the vapor from the outlet at the top of the feed tank are cooled in an air cooler and then sent to a reflux tank. The liquid phase after gas-liquid separation is returned to the top of the tower, while the off-gases are sent to the sulfur treatment unit for further processing under normal operating conditions. To prevent dew point corrosion and blockage by ammonium salt crystals, the exhaust gas temperature should not be lower than 100°C. To prevent high-temperature scaling of CaCO3, hydrochloric acid is injected proportionally into the slurry feed line at the inlet of the stripping tower; if necessary, acid can also be manually added to the packing in the lower sections of the tower. 2. Clarification section: The slurry at the bottom of the distillation tower is cooled before being sent to a clarification tank for clarification; after clarification, the solid suspended particles in the water are less than 100 ppm. To accelerate clarification, a certain dose of flocculant solution is continuously pumped in and stirred evenly. The clarified water is pumped from the bottom of the clarifier overflow tank through the clarifier pump; some of it is sent outside the facility for further treatment, while some is directed for reuse. 3. Thickenning and filtration section: The slurry that has thickened at the bottom of the clarification tank contains about 10 wt% solids; it is pumped to a slurry tank where it is further thickened to a solids content of about 25 wt%. The slurry coming out of the bottom of the slurry tank is sent to a vacuum belt filter for dewatering, and the filtrate is collected and returned to the clarification tank. The filter cake is discharged from the area by a filter cake conveyor. Last edited by Tianya Langji on 2008-1-2 at 08:50.]

Duo, try to write more and learn more things. It seems that Guotai is about to undergo major repairs again

The wastewater treatment processes are more or less similar; what truly matters are the final amount of wastewater treated, the environmental performance metrics, and the costs involved. Who can provide a cost analysis for wastewater treatment?

The teachers on the 4th and 5th floors described it very well; it would be even better if they could provide P&ID diagrams