Egypt Case Study: How our engineer commissioning a irrigation desalination

Introduction:

The project was located in Cairo of Egypt, which was an orchard with 1000 acre area. Raw water was Nile river water. Our Egypt client adopted our brackish desalination for irrigation to produce fresh water for meeting his orchard irrigation need. The production capacity was totally 480 tonnages per day(20 T/H).

Technological Process

desalination for irrigation

Preparation before commissioning

S.N Checking Items Requirement Standard
1 Whether analysis of Reverse Osmosis inlet water has been done. The result of water quality report meets the requirement of reverse osmosis inlet.
2 Whether commissioning chemicals, commissioning tools, analysis instruments, and meters are available. Commissioning chemicals meet the design requirements, and tools and analysis instruments have been ready.
3 The water, electricity and gas system of the process system has the ability of continuous supply, and whether the drainage ditch has the discharge conditions. Water, electricity, gas system has the ability of continuous supply. Drainage ditch has the discharge conditions, drainage is smooth, and in line with the design requirements.
4 Whether the water tanks related to the reverse osmosis have been cleaned, and cross-sectional area has been measured  (feed water tank, concentrated tank and production tank). No debris in the clean water tanks, and cross-sectional area has been measured.
5 Check whether all piping are connected completely based on design requirements, and whether piping skips are installed solid. Check whether all piping are connected completely based on design requirements, and whether piping skips are installed solid. Meet the requirements of design drawings, and skips installed solid.
6 According to PID, check whether the quantities of all piping, pressure gauges, level switch, flow meter, conductivity meter, and SDI instrument are in line with design requirements. Comply with design requirements.
7 Whether MCC and PLC control system can be powered. Meet the design requirements, able to show normal data.
8 Whether all valves can be operated normally, and the speed of the valves has been adjusted or not. Pneumatic valve can normally on-off, the speed of the valve meets the technical process requirements.
9 Whether process pipelines have been pressure test, no leakage. Meet design requirement, no leakage.

On-site Problems&Solutions

1. Pretreatment system: we were only responsible for the reverse osmosis system, excluding pretreatment. Due to the pretreatment was substandard, 6.67 SDI, which will cause membrane fouling too fast. In order to improve the pretreatment system, our technical engineer suggested increasing the filters to reduce the filtration flow from 35m/h to 8m/h, the effect was improved. And adding the alums to improve SDI as there was no PAC on site.

2. Membrane fouling: we have not previously designed pure water flushing in this system, so some pipelines were rebuilt to increase the daily fresh water flushing and reduce the fouling.

3. Water drain problem: the owner directly connected the concentrated pipes and backwash pipes of filters to water intake for saving pipelines, which resulted in water intake TDS and turbidity rising, and had an effect to RO operating. So we suggested they revise the pipelines by connecting concentrated pipes and backwash pipes to other discharges.

4. Unqualified processing of pressure vessel connecting part called “Grenade”: There are two kinds of solutions on this problem. First one is to reprocess Grenade, and the second one is to curtail 2cm length of connecting seal part. Last we adopted the second one, and solved the problem within half an hour.

Conclusion

Finally, the Engineer Victor Zhang completed the installation and commissioning of this project sucessfully within half a month(2015/12/21-2016/1/5). Our client adopted our brackish water RO system to purify Nile water into fresh water for irrigation, which can greatly save irrigation water and prolong lifespan of fruit trees. At the same time, he was very satisfied with our service and we were pleased to get that!