Sour Water Stripper

A refinery in South America asked ProDecon® to undertake the full unit decontamination of the refinery’s Sour Water Stripper (SWS) unit. The decontamination scope was undertaken from battery limit to battery limit, covering all vessels, exchangers, coolers, piping and drain drums.

The contamination found in these units can lead to different problems downstream impacting plant efficiency, as well as posing increased fire, health and environmental risks.

The process equipment of the SWS usually accumulates high concentrations of hydrogen sulphide. ProDecon’s H2S scavenger, ProDecon-216™, is capable of treating high concentrations of H2S in just a couple of hours. The next step in the decontamination process was to remove the organic deposits and neutralise the pyrophoric iron sulphide. V-Purge™ was used to cover these two decontamination requirements simultaneously. Used in a vapour phase process V-Purge™ incorporates sophisticated chemistry that removes hydrocarbon deposits, eliminates LEL, H2S, Benzene and other hazardous gases and oxidises pyrophoric iron sulphide deposits in a single step.

V-Purge™ is biodegradable and it separates to its water and oil phase in a short period of time without the addition of emulsion breaker. This allowed for direct disposal through the refinery waste water system with no need for off site disposal.

V-Purge™ was injected into the steam flow at strategically selected points to carry it throughout the system. This ensured contact with all surfaces to rapidly decontaminate the system in 10 hours

The process of decontamination was monitored by ProDecon’s own gas

sampling method using speciality testing equipment and complex field analysis. Testing through this steam monitoring allows the trend to be monitored and the decontamination can be verified as complete and system handed over immediately upon completion.

The reduction of H2S over the course of chemical injection is shown in Graph 1.

Graph 1: H2S measurements.

Customer Verified results

ProDecon® successfully completed this project within the allowable timeframe. Sampling and testing proved the efficiency of decontamination and pyrophoric neutralisation. The cleanliness of the vessels’ internals was reported to be very good and this is shown in Picture 1.

Picture 1: Sour Water Surge Drum Internals.

ProDecon® deliver again on Safety, Quality and Schedule