What treatment approaches are suitable for the wastewater from units such as atmospheric and vacuum distillation, hydrogenation, delayed coking, and sulfur recovery?

Oily wastewater is sent to the wastewater treatment plant for biochemical treatment, while sulfur-containing wastewater must be subjected to stripping treatment before its purified water is sent to the wastewater treatment plant for further processing.

The wastewater treatment process in refining plants is relatively complex; it usually involves classified treatment, and more than one type of wastewater is generated. Oil-containing wastewater and some sulfur-containing wastewater are sent to the wastewater treatment plant, while another portion of the sulfur-containing wastewater is processed in an acidic water stripping unit. Some of the wastewater generated in delayed coking should be treated separately; saline and alkaline wastewater also needs to be treated separately. Rainwater and domestic wastewater do not require special treatment. By the way: the treated water can be reused

Wastewater from refineries is generally divided into oily wastewater and sulfur-containing wastewater. Oil-containing wastewater is generally sent to wastewater treatment plants for treatment using methods such as A/O, and is discharged only after meeting the **discharge standards. Sulfur-containing wastewater is generally treated using a wastewater stripping unit; the recovered water is reused, while sulfur is converted into hydrogen sulfide and sent to a sulfur recovery unit for recovery.

The oily wastewater from our company’s various refining units is sent via concealed pipes to the wastewater treatment plant, where it undergoes treatment processes such as oil separation, flotation, and biological treatment. The sulfur-containing wastewater from these units (from the tops of catalytic distillation towers, coking distillation towers, etc.) is first subjected to steam stripping to remove the sulfur and ammonia nitrogen contained in it, after which it is sent to the wastewater treatment plant to be treated together with the oily wastewater.

The wastewater is treated by an acidic water treatment unit before being sent to a wastewater treatment plant. The cost of recovering it is high, but a recovery rate of over 85% can be achieved; generally, small refineries do not opt for this approach

I agree with what was said on the 5th floor. We just completed a delayed coking project, and martial arts was handled following the same approach. As a precaution, the treatment of ammonia nitrogen and COD was carried out using the dual A/O method.

It is recommended to install two sets of wastewater stripping units, following the principle of treating clean and polluted wastewater separately: one set for treating wastewater from atmospheric and vacuum distillation as well as coking processes, and the other set for treating wastewater from hydrogenation and sulfur processing units. This is because the wastewater from atmospheric and vacuum distillation as well as coking is relatively dirty; it contains low levels of H2S and NH3, and also has chloride ions. The purified water is then used as feedwater for electrodesalination in these processes. In comparison, the wastewater from hydrogenation and sulfur units is cleaner, and it contains higher levels of H2S and NH3; the purified water can be used as makeup water for the hydrogenation units.

Hydrocracking, wastewater discharge, sources of wastewater, methods of discharge, types of wastewater, wastewater volume in t/h, water quality in mg/l, destinations of wastewater: COD, oils. Cold high and cold low pressure separators in the reaction section, as well as the top reflux tanks of the stripping column and the butane removal column. Continuous flow. Sulfur-containing wastewater: 21.635; hydrogen sulfide and ammonia. Acidic water stripping unit; top reflux tanks of the distillation column and the naphtha distillation column. Continuous flow. Oil-containing wastewater: After being pressurized by pumps, it is sent to the water injection tank for reuse as water for the plant. Raw oil dehydrators, pump cooling systems, equipment low-point drains, floor washing, etc. Continuous (intermittent) flow. Oil-containing wastewater: 5(210), 500, 230. Wastewater treatment plant: During the initial stage of operation, rainwater is combined with the oil-containing wastewater; later on, it is discharged into the clean wastewater system in order to reduce the plant’s wastewater treatment burden. Domestic wastewater: Discharged intermittently into the domestic wastewater system

Wastewater from refineries is generally divided into oily wastewater and sulfur-containing wastewater. Oil-containing wastewater is generally sent to wastewater treatment plants where processes such as oil separation, air flotation, and A/O treatment are carried out; it is then discharged only after meeting the **discharge standards. Sulfur-containing wastewater is generally treated using a wastewater stripping unit; the recovered water is reused, while sulfur is converted into hydrogen sulfide and sent to a sulfur recovery unit for recovery. The finally purified water is then sent to a wastewater treatment plant where it is treated together with oily wastewater and other types of wastewater.