Qatar Primary Materials Company, Doha, Qatar

Moisture Reduction Systems Limited solve water-recirculation problem for QPMC in Doha.

Background

QPMC required large amounts of water for a newly completed sand-washing plant at a site close to the capital, Doha. The ambient temperature during the day can soar up to 50C and QPMC required around 500,000 gallons of clean water on a daily basis so as to produce high-quality washed building sand.

Challenge

  • Find water in the desert
  • Reduce significant water costs
  • Re-cycle water
  • Transform operations

Solution

The solution to recycle the water extracted from the stockpiles came about via the observation of the numerous tankers delivering water to the site each day. Of course, additional quantities would be required time and time again. Further observation centred on the high ambient temperature, which would cause a great deal of condensation within the material.

Using the design criteria and calculations to suit the prevailing D10 sieve sizes, the system ensures that no fines are removed during the process and only clean water was discharged so as to enable constant re-circulation back to the washing plant for subsequent re-use.

The result was that 90% of the initial wash water is returned to the plant on a continuous basis, while only 3% is lost to evaporation. Consequently, the remaining moisture content of the material is around 7%.

A spokesperson for QPMC stated that the system “performs well…allowing us to either load directly from live stockpiles or transport material to stock areas very soon after production.”

QPMC later noted that their “plant floor remains clear and dry, which benefits both transport vehicles and our loader operators.” However, the most favourable outcome of the whole project was that QPMC were firstly, very happy with the service they received from Moisture Reduction Systems Limited, and secondly, that the system had “given them an edge in a very tight and competitive market.”

Scan_Doc0267Scan_Doc0264