HydroSOLV® Selective Impurity Removal
The demand for water and the strain on resources has never been higher than it currently is. With the increasing need for housing development and changing climatic conditions, planners and system designers alike have more complex regulatory and sustainability issues to resolve. These driving forces are leading increasingly to water recovery from systems that would once have been classed as waste water, such as grey water recovery technologies and the use of natural waters such as borehole derived waters. Depending on the source of the water, there is often a significant chance that it will contain some undesirable materials that would prohibit its intended use, without treatment to remove these. A good example of this would be borehole water that is intended for drinking, may contain pesticides if the borehole is in an agricultural location. To render the water fit for the intended purpose, pesticides may be selectively removed from the water using HydroSOLV® carbon filtration technology; this can provide a very cost effective method of treating the water, compared to other techniques that are available. HydroSOLV® products, will look externally like water softeners and may indeed function like them, they may or may not have chemical regenerant bins (like the brine bin on softeners) depending upon the function it is performing. The picture below shows two HydroSOLV® AK units, which are designed for the removal of pesticides and chlorine. The HydroSOLV® range of products is a bespoke range of products designed to meet the needs of selective impurity removal and can be summarised as:
The vessels in the HydroSOLV® AK range are packed with Granular Activated Carbon (GAC) media, suitable for the intended application. Typically these filters are used to remove residual chlorine from waters intended to pre-feed reverse osmosis systems and the removal of pesticides from drinking waters. Other uses of these filters include the removal of taste, odour and colour from drinking waters, which may not be harmful, but may be desirable for ‘aesthetic’ purposes.
The BR range is intended for the removal of iron from drinking water systems, or other systems where sensitivity to iron may be a problem (for example the staining of laundry). The drinking water inspectorate (DWI) recommends that the dissolved iron level in water does not exceed 0.2ppm, thus the BR range can be used to remove iron from borehole water to meet this target. For excessive iron levels Hydrotec can advise oxidation / filtration methods as an alternative. In addition to the direct health implications, high iron levels are also problematical for water hygiene reasons too; iron is known to be a key nutrient of many bacteria including legionella, so its presence in systems should be limited and controlled. Smaller amounts of manganese can also be removed with this technique; however for higher levels the HydroSOLV® GS range will be required.
The GS range is formulated for the removal of manganese from water systems. The DWI prohibits its presence above 0.05ppm for health reasons, however this material, often present in borehole waters can cause significant black staining on sanitary ware and laundry if not removed from the system.
Many natural and recovered waters can have excessive turbidity that would render them unsuitable for use directly and in addition could prevent other systems working effectively (such as HydroPUR® ultra violet disinfections systems) or block and contaminate the water system downstream. The HydroSOLV® MS range, can feature a number of different internal media to address these filtration requirements, based both on particle size, loading and nature of contaminant. These systems are often used in conjunction with other products in the HydroSOLV® range, to reduce contaminant loading and assist in improving the biological quality of the water.
The S range is designed to de-acidify waters that naturally have a low pH. Acid in water can lead to excessive corrosion both of key plant, such as water heaters, heat exchangers etc, but can also corrode the entire system, particularly distribution systems made of copper and steel. The HydroSOLV® S employs selected lime based media to effectively neutralise the threat posed by acidic waters. For all applications of the design of HydroSOLV® systems, we would recommend that a detailed water analysis study be conducted in our laboratories. Dependant on the application, Hydrotec will advise on the best media to use within a range (for example which is the best grade of GAC to use in a HydroSOLV® AK unit) and from this we can also predict the life of the media, and/or back washing and regeneration frequency requirement.
For all applications that require the use of HydroSOLV® products, the Hydrotec design department will be pleased to help you.