Multi Media Water Filters (Sand Filters / Actived Carbon Filters)
3A Makina is the leading manufacturer of sand filters, most popular type of multimedia filters, in Turkey.
Sand filters are used as multimedia filters to remove suspended solids from water and wastewater. Because they have one layer of filter media, sand filters remove only relatively large solids (usually in the range of 40 micron and larger). The effective size of each granule of sand typically varies from 0.35mm – 1.2mm. Larger granules yield coarser filtration. Finer granules yield finer filtration.
Removing suspended solids smaller than 40 microns requires filters with either two or three layers of filter media. These are referred to as dualmedia filters or multimedia filters. When sized properly and with the correct configuration of filter media, these multimedia filters can remove suspended solids as small as 5 micron.
The smaller the solid to be removed, the slower the water must pass through the media and the finer the granule of media must be. Very often the end user doesn’t know how small a solid must be removed. In those situations, how the filtered water will be used will determine how small a solid should be removed.
The higher the concentration of suspended solids, the larger the diameter of the multimedia filter needs to be. All filters have a maximum concentration of suspended solids that can be managed without compromising filter performance.
Backwash water is used to clean the multimedia filters and flush out the suspended solids that have been trapped in the media bed. Water for backwashing can come either from the filters themselves or from an external source of clean water (such as a storage tank).
If backwash water comes from the sand filtration system, there must be more than one sand filter in the system. Sand filters are backwashed one-at-a-time. During the backwash cycle, a portion of filtered water exiting the other multimedia filter(s) in the system is used to clean the dirty multimedia filter. During these periods (which typically last for several minutes per filter), the amount of filtered effluent flowing downstream of the filter is reduced by the amount of water required for backwashing.
In cases where this temporary reduction in flow is acceptable, there will be two or more filters in the system.
Clarifiers / Thickeners
Clarifiers are designed to receive raw or waste water from the incoming water flow which has been screened to remove larger solids and grits with the help of the scrapers.The velocity of the water is reduced in the system ensuring that the incoming water is distributed hom in a radial manner to all directions.
This application provides maximum setting time causing efficient separation of settled particles from the water.The collected particles travel down the trough the slope forming sludge. The sludge is scraped off by a scraper bridge which is included in the system. Finally the clear water overflows via a launder located at the top portion after leaving the scraper system.
Clariflocculator is the combination of clarification and flocculation in a single tank including two concentric tanks where the outer tank serves as a clarifier and the inner tank serves as a flocculation basin.
The water enters the flocculator, where the flocculating paddles enhance flocculation of the feed solids. As heavy particles settle to the bottom, the liquid flows radially upward in the clarifier zone. The clarified liquid is discharged over a peripheral weir in to the peripheral launder. The remaining sludge is raked with a scraper to the bottom near the central weir from where it is routed to the sludge chamber and discharged.
Travelling Scraper / Thickener
Travelling bridge scraper is designed according to span as Full Wall, Half-Wall, Steel Profile or to avoid high wind loads as Truss Beam. Carriages, which are located at both ends of the bridge, can travel on rails with or without pinion rock or on polyurethane tyred wheels with guide wheels. The drive unit can be mounted either at the end carriages or at the middle of the bridge. Bridge movement controlled by limit switches.
For removal of settled sludge, both scraping and suction methods by pumps can be used. The solids settling in the tank are scraped by scraper or pumped to solids hopper. Also for removal of floating matter; skimming or pumping types are available. Power feed can be done by using cable carrying roller or by means of motorized or spring loaded cable drums.