http://WWW.GREENWATERCONCEPTS.IN
GREENWATERCONCEPTS 5a2a4b8be9ea0107781bd373 False 398 48
OK
background image not found
Found Update results for
'periodic backwash'
12
Iron removal media - Purolite MZ10 plus Aventura in association with Purolite, a premier manufacturer of resins from USA, offers iron removal media MZ10 Plus. The dark-to-black colored catalytic media can remove soluble iron, manganese, hydrogen sulfide, arsenic and radium from water supplies. For drinking water applications the media can be effective for over 10 years. Advantages over the existing iron removal media - Can take max iron concentrations up to 20ppm - Can reduce iron, Mn and H2S up to< 0.1 ppm- - No limitation of alkalinity and TDS inwater - Needs only periodic backwash with treated water - Can be operated at high temperatures and high differential pressures without breakdown ofmedia - No pre-treatment required to remove chlorine in feed water - Used with chlorine, the media offers excellent resistance to biological contamination - NSF approved Green Water Concepts India Pvt Ltd is one the major supplier of Purolite MZ 10 plus media across India
UV System WHAT IS UV DISINFECTION SYSTEM AND HOW DOES IT WORK? UV Disinfection System is an extremely effective way to combat microbial contamination in water. However, microbes have to be exposed to UV-C light in the proper amount in order to effectively disinfect the water. UV Disinfection Systems are used in many different applications ranging from the purification of drinking water in individual homes to disinfecting water supply of entire townships. UV treatment for water is recognized as the safer and more cost-effective way to disinfect water for industrial applications. UV sanitization is useful in almost any application where microbial free, safe and pure water is required; and where there is a chance of the water being contaminated before it reaches the final point of use. How Does UV Disinfection System Work? UV light disinfects by penetrating microorganisms and destroying their DNA. DNA plays an important role in organisms’ functions and reproduction hence destroying the DNA prevents the organism from being active and multiplying. This UV energy (wavelength of 240-280 nm) is also naturally found in sunlight in very small quantities. The same energy is produced in stronger intensities with help of high mercury discharge lamps, commonly known as UV lamps. No bacteria, viruses, molds or their spores can survive when exposed to the correct dose of UV light. Therefore UV is considered as the best solution for water sterilization. Industrial Applications of UV Disinfection System Ultraviolet disinfection system is not simply a lamp inside a pipe. The UV Reactor must be designed to ensure that all microbes receive sufficient exposure to the UV light (dose).Based on the hydraulic properties of water; the reactor needs to be optimized to guide the flow in a manner so as to maximize residence time and boost turbulence. Well designed UV systems are producing consistently exceptional results in the industrial applications. Few Examples : Food and Beverage – UV disinfection system can help to achieve quality of water as per specifications laid down by the FDA ( Food and Drug Administration ) Bio- Pharmaceutical – Water used in Pharmaceutical and healthcare products and for CIP (Cleaning in Place) must be free of chemicals like chlorine, ozone, and pathogens. Most pharmaceutical companies depend on UV systems for water disinfection. Cosmetics – Water that is free of microorganisms and toxins ensure quality and enhance the shelf life of cosmetics. UV Sterilization is the preferred choice for the cosmetic industry across the globe. Centralized Drinking Water – A UV system is an easy, affordable solution to ensure pure water in each and every tap of your home or office. Waste Water Disinfection and Reuse – To combat the problems of water scarcity and rising cost of fresh water, UV Disinfection can help by treating the waste water in the tertiary stage. UV systems that are specially designed for wastewater can thus disinfect wastewater so that the water can be reused for secondary purposes such as flushing and gardening. Swimming Pools – Traditionally, chlorine has been in use to ensure clean water in swimming pools. However, it is increasingly being known that with chemical disinfection, chemical reacts with many other organic matters to form hundreds of new chemicals which are harmful. While UV is recognized as safer and more cost effective way to disinfect swimming pools. Benefits of UV Disinfection System Natural – UV is nature’s way of purification. Environmentally Friendly – No Toxic by-products are formed during UV disinfection process Effective – All known microorganisms are susceptible to UV light Economical – Lowest operating cost amongst disinfection systems Safe& Chemical Free – No addition of chemicals hence no danger of overdosing Fast – It is In-contact purification therefore Instant Easy to Manage – Well designed systems like the Alfaa UV systems come with many advanced features like CFD (Computational Fluid Dynamics), high-efficiency electronic ballasts, and extremely precise UV intensity monitors which make them highly effective and hence easy to manage. Does a UV Disinfection System need periodic maintenance? There can be some cases where the water is not adequately pre-treated and turbidity levels are low. In such cases, routine inspection and cleaning can be carried out every 6 months. In the case of high turbidity and hardness, the cleaning frequency might need to be increased. Finally, the UV lamp has a limited life and must be replaced once it is exhausted. In the unlikely event of premature failure of the lamp, the monitoring circuit will provide the signal to advise replacement.
AFM, Glass Media and Sand Filtration Systems, a Comparison of Technologies and Optimization of Performance. Media Bed mechanical sand filtration systems comprise of, gravity flow, pressure, and moving bed continuous backwash filtration systems. In all cases, the most common mechanical filtration media is quartz silica sand. The quality of quartz sand is a variable depending upon the country and the location of the deposit. There is a requirement for a consistent quality of filter media for all industries using media bed filtration in order to standardize and optimize the filtration process. This aspect becomes more important for filters, that have a pressure gradient across the bed such as horizontal filters, or filters that have not been installed on a perfectly level base. The performances of seven different types of filtration media were physically evaluated by IFTS (1) one of the leading independent accredited laboratories in Europe for the evaluation of products used by the water industry. History Sand has been used for over 200 years in Europe as a means of filtering Drinking water. A company in Scotland in 1804 was the first documented report of a company using sand in a slow bed sand filter (2). Slow bed sand filters typically operate at water flow velocity of 0.1m/hr and use a coarse grade of sand and gravel. The filters depend on the maturation of the sand as a biological filter before they provide adequate mechanical water filtration. Slow bed sand filters provide excellent water quality and are still used for the treatment of drinking water. Approximately 15 percent of all water supplies in the UK currently use slow bed filters, but they are being phased out in favor of RGF (Rapid Gravity Filters) and pressure sand filters in order to save space. RGF filters for drinking water operate at water flow velocity of 6m/hr whereas pressure filters typically operate at 12m/hr. The water flow velocities of RGF and pressure filters are therefore 60 to 120 times faster than slow bed filters. The higher water velocities change the bio-dynamics of the filtration process which impacts on filter performance leading to bio-instability and transient wormhole channeling of unfiltered water through the filter bed. The performance of any media bed will be inversely proportional to the flow velocity, which is a function of the filter diameter, its surface area and bed depth. The bar graph compares the performance of AFM and Leighton Buzzard sand from England. The slower the filter flow velocity the higher the performance, the relationship is exponential but the coefficient depends on the media characteristics and particle size used for performance evaluation. One of the key issues in the drinking water industry is the ability to remove a parasite called Cryptosporidium, which is almost completely resistant to chlorine and only measures 4 micron in size. If sand filters are operated at water flows in excess of 12m/hr it becomes increasingly difficult to ensure adequate water quality and the removal of parasite. Water treatment system tend to operate at the highest possible water flow rates in order to save space and reduce capital cost. AFM has been shown to provide performance advantages over sand, which permits higher water flow rates and reduced capital cost of illustrations. Typically 50% higher water flow rates can be used with AFM over sand while still maintaining good performance. Filtration performance also depends upon filter configuration; horizontal filters save space and maximize surface area. Bed depth is shallower which reduces absorption capacity for small particles. Also, a differential pressure gradient across the bed reduces performance when compared to vertical filters that have a consistent pressure gradient and a deep bed. The differential pressure promotes biofouling of sand, biodynamic instability and transient wormhole channeling; the problems are largely resolved by using AFM which does not suffer from biofouling. Pressure Differential During the run-phase large solids will accumulate on the top of the filter bed and small solids will penetrate the bed. Small particles attracted by electrical (Van Der Waals) forces may become trapped on the surface of the media. Sand and most media carry a negative charge on Zeta Potential. In water treatment, coagulants and flocculants such as; Lanthanum chloride, aluminium chloride, ferric chloride, PAC (polyaluminium chloride) or polyelectrolytes may be applied to drop the zeta potential, increase coagulation and flocculation as well as increasing electrical attraction. In some industries including pre-treatment prior to membranes or the aquarium industry, the use of chemicals would not be advisable. Reduction of the zeta potential and coagulation can nevertheless be achieved by the rapid movement of water, cavitating static mixers. In addition to mechanical and electrical attraction, there will also be some degree of molecular sieve filtration. This will be the case with activated carbon, and to a lesser extent with new sand. The ability of sand to adsorb is a function of the silicon to aluminium ratio and how the molecules are configured. An example of natural ion exchange molecular sieve sand is the zeolitic sand clinoptilolite. Zeolites are used in water treatment as a mechanical filtration media and also as an ion exchange mineral for the selective removal of ammonium and radioactive nuleotides from freshwater. Zeolites cannot be used for marine systems or water with a high TDS because the competing cation will prevent ion exchange. In freshwater systems zeolites provide a good substrate for the growth of autotrophic nitrifying bacteria, a characteristic that is likely due to the adsorption of ammonium into the mineral and its availability to be metabolized by autotrophic species such as Nitrosomonas spp.
Iron Removal Plants Iron removal plants can be based on different filtration media, depending on the iron and manganese concentration, the oxygen level, CO2 content and hardness of the water. Plant principle: First, air is injected in order to oxidize the iron. The oxidized iron will then precipitate on a sand filter. An MnO2 layer in the sand bed will catalyze the oxidation of residual iron. Backwash will be done by water and by air. More on iron removal principles Iron removal plant flow diagram:
1
false