Advantages of Drintec™ Upflow Contactors
Main advantages and disadvantages of Drintec™ Upflow Contactors vs Traditional Downflow Contactors.
|Traditional downflow contactors
- Backwash cycle cleans limestone media and prevents iron oxide particles and other sediments from fouling or coating the media.
- Large particle limestones are prevented from leaving the filter tank due to the bottom underdrain.
- Requires frequent automatic or manual backwash cycles to clean limestone media during replenishment and to avoid media compaction.
- Requires spare units to operate during replenishment and backwashing.
- Potentially higher headloss due to limestone media compaction.
- Longer downtime during media replenishment.
- Variation in tank head loss due to changes in bed height.
- Lost in CO2 application efficiency due to continuous backwash.
- Variation in water quality due to changing bed height CO2 concentration in the media.
- Waste water treatment plant (WWTP) required for treating large amounts of backwash water. This includes settler and sludge removal units as well as water recovery system.
- Return of cleaned water from the WWTP to the entrance of the plant causes flow increases and potentially turbidity events. Therefore reuse from backwash water requires sufficient storage for constant feeding .
- Sludge from WWTP settler needs to be disposed.
- Need for a separate storage area outside the filter area.
- Operators with high technical skill required.
- Delicate design due to motors and automation. Risk of failure, even under harsh environmental conditions.
- Higher energy consumption
- Higher capital and O&M costs.
|DrinTec™ upflow contactors of constant height
- Constant water quality due to continuos bed height.
- Refilling is done in the in-built silo and not directly on the bed’s surface. No turbid water is generated during refill. No need to backwash and divert turbid water every refill.
- No frequent backwash required if good limestone, only sponging every 6 months recommended.
- No need for spare units.
- A very even consumption among tanks as they have same hydraulic head loss that remains constant during operation and refilling.
- Continuous operation. No need to stop the plant during replenishment.
- Lower head loss experienced.
- Effluent turbidity is typically low and below
- 0.5 NTU.
- No backwash water treatment plant needed. Pumps and blower used in other sections of the desalination plant can be used for initial clean-up of the media and eventual sponging.
- No sludge to be disposed off.
- Low energy consumption as no frequent for backwashing is needed.
- Robust design. No moving parts and low risk of failure, even under harsh environmental conditions.
- Higher CO2 efficiency due to constant operation, no backwashing and long contact times.
- No need for separate storage area. In-built silos allow for and autonomy of 30 days or more.
- Lower operation health and safety factors due to no moving parts.
- Simple to operate. No high technical skills required.
- Less expensive on capital costs and O&M.
- Good quality limestone recommended (< 0,3% Fe2O3 ) to prevent iron or other sediments from fouling or coating the media and prevent the need for backwashing.
- Percentage of limestone particles less than 0,1 mm to be minimized (< 1%) for prevent limestone been dragged by up-flowing water.
Contact us for more information