Application To Subsurface Treatment

The application of adsorption to contaminated groundwater remediation is not only an important subject, but one we could expand upon into several volumes unto itself. At best, all we can do is try to provide a concise overview in this volume. When we discuss this subject, we cannot separate groundwater treatment from subsurface soil treatment, as the two often go hand in hand. Furthermore, carbon adsorption is not the only technology applicable to subsurface (soil and water) remediation, but it...

Applications

Applications of carbon adsorption go far beyond conventional water treatment applications which we will discuss in a general sense shortly. Table 8 provides a summary of the key applications of carbon adsorption systems for liquid phase applications. Table 8. Liquid Phase Applications of Carbon Adsorption. Table 8. Liquid Phase Applications of Carbon Adsorption. Granular activated carbons (GAC) installed in rapid gravity filters Removal of dissolved organic contaminants, control of taste and...

Biosolids Regulations

EPA has developed comprehensive federal biosolids use and disposal regulations , which are organized in five parts. These parts are general provisions, land application, surface disposal, pathogens and vector attraction reduction, and incineration. Parts of the regulations which address standards for land application, surface disposal, and incineration practices consist of general requirements, pollutant limits, operational requirements, management practices, frequency of monitoring,...

Filter Media Selection Criteria

Due to the wide variety of filter media, filter designs, suspension properties, conditions for separation and cost, selection of the optimum filter medium is complex. Filter media selection should be guided by the following rule a filter medium must incorporate a maximum size of pores while at the same time providing a sufficiently pure filtrate. Fulfilment of this rule invokes difficulties because the increase or decrease in pore size acts in opposite ways on the filtration rate and solids...

Granular Media Filtration

Granular media filtration is used for treating aqueous waste streams. The filter media consists of a bed of granular particles (typically sand or sand with anthracite or coal). The anthracite has adsorptive characteristics and hence can be beneficial in removing some biological and chemical contaminants in the wastewater. This material may also be substituted for activated charcoal. The bed is contained within a basin and is supported by an underdrain system which allows the filtered liquid to...

Industrial Water And Wastewater Treatment

The markets for ozone in industrial water and wastewater treatment are quite small. Industrial applications for ozone could grow. The use of ozone for treating photoprocessing solutions is a novel application that has been limited, but might grow. In this process, silver is recovered electrolytically then the spent bleach baths of iron ferrocyanide complexes are ozonated. Iron cyanide complexes are stable to ozonation so that the ferrous iron is merely oxidized to ferric, which is its original...

Introducing The Physical Treatment Methods

The following technologies are among the most commonly used physical methods of purifying water Heat Treatment - Boiling is one way to purify water of all pathogens. Most experts feel that if the water reaches a rolling boil it is safe. A few still hold out for maintaining the boiling for some length of time, commonly 5 or 10 minutes, plus an extra minute for every 1000 feet of elevation. One reason for the long period of boiling is to inactivate bacterial spores (which can survive boiling),...

Ion Exchange And Carbon Adsorption

Ion exchange and carbon adsorption are unrelated technologies, and often have different objectives. They are however oftentimes used in compliment to achieve Ion exchange is a reversible chemical reaction wherein an ion (an atom or molecule that has lost or gained an electron and thus acquired an electrical charge) from solution is exchanged for a similarly charged ion attached to an immobile solid particle. These solid ion exchange particles are either naturally occurring inorganic zeolites or...

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NPDES Permit National Pollutant Discharge Elimination System permit is the regulatory agency document issued by either a federal or state agency which is designated to control all discharges of pollutants from point sources into U.S. waterways. NPDES permits regulate discharges into navigable waters from all point sources of pollution, including industries, municipal wastewater treatment plants, sanitary landfills, large agricultural feed lots and return irrigation flows. Nitrification An...

Principles Of Ozone Effluent Treatment

Ozone was first discovered by the Dutch philosopher Van Marun in 1785. In 1840, Schonbein reported and named ozone from the Greek word ozein, meaning to smell. The earliest use of ozone as a germicide occurred in France in 1886, when de Meritens demonstrated that diluted ozonized air could sterilize polluted water. In 1893, the first drinking water treatment plant to use ozone was constructed in Oudshorrn, Holland. Other plants quickly followed at Wiesbaden (1901) and Paderborn (1902) in...

Recommended Resources For The Reader

The following references offer some good general reading and design-specific 1. Cheremisinoff, P.N., Wastewater Treatment Pocket Handbook, Pudvan Publishing, Northbrook, IL, 1987. 2. Cheremisinoff, P.N., Pocket Handbook for Solid-Liquid Separations, Gulf Publishing Co., Houston, TX, 1984. 3. Noyes, R., Unit Operations in Environmental Engineering, Noyes Publishers, NJ, 1994. 4. Kirkpatrick, J., Mathematics for Water and Wastewater Treatment Plant Operators, Ann Arbor Science Pub., Ann Arbor,...

Sludge Lagoons

This is a technique that relies both on the settling characteristics of sludge and solar evaporation. The considerable labor involved in sludge drying bed operation may be avoided by the use of sludge lagoons. These lagoons are nothing but excavated areas in which digested sludge is allowed to drain and dry over a period of months or even a year or more (refer to Figure 22 for an example). They are usually dug out by bulldozers, or other dirt-moving equipment, with the excavated material used...

The Final Touches To Water

< > Disinfection - water completely free of suspended sediment, is treated with a powerful oxidizing agent usually chlorine, chlorine and ammonia (chloramine), or ozone. A residual disinfectant is left in the water to prevent reinfection. Chlorine can form harmful byproducts and has suspected links to stomach cancer and miscarriages. < > pH adjustment - so that treated water leaves the plant in the desired range of 6.5 to 8.5pH units. conditioner, as well as a some fertilizer value....

The Plateandframe Filter Press

This type of filter allows pressurized filtration of a slurry mixture to remove solids. A set of filter plates is sandwiched together in series with a configuration similar to the plates on a plate-and-frame heat exchanger. After the plates are compressed together hydraulically, a channel throughout all the plates allows the slurry to be pumped into one side of each of the plates. The filtrate goes through the filter media on the plate leaving the solid cake on the media. Filtrate on the other...

Water Treatment In General

Water must have eye appeal and taste appeal before we will drink it with much relish. Instinctively we draw back from the idea of drinking dirty, smelly water. Actually far more important to our well-being is whether or not a water is safe to drink. If it holds disease bacteria, regardless of its clarity and sparkle, we should avoid it. Let's consider these two highly important aspects of water potability and palatability. Regardless of any other factors, water piped into the home must be...

What Eletcrodialysis Is

The principle behind electrodialysis is that electrical potential gradients will make charged molecules diffuse in a given medium at rates far greater than attainable by chemical potentials between two liquids as in conventional dialysis. When a DC electric current is transmitted through a saline solution, the cations migrate toward the negative terminal, or cathode, and the anions toward the positive terminal, the anode. By adjusting the potential between the terminals or plates, the electric...

What Sludge Is

When we think of sludge, what automatically comes to mind is sewerage. Water carriage systems of sewerage provide a simple and economical means for removing offensive and potentially dangerous wastes from household and industry. The solution and suspension of solids in the transporting of water produces sewage. Thus, the role of solids and sludge removal at Sewage Treatment Plants is apparent. Sludge removal is complicated by the fact that some of the waste matters go into solution while others...

The Rotary Drum Filter

This continuous filter is used when the solids in the slurry can be easily suspended in solution and remain there. In this filter a cylindrical drum sets horizontally half submerged in a trough holding the filtration slurry. The drum is coated with a filter media and a vacuum is pulled on the inside of it. The filtrate passes through the filter media leaving the solids on the outside of the drum. The drum is rotated continuously allowing the solids to be washed and dried before they are removed...

Carbon Adsorption In Water Treatment How Adsorption Works

Activated carbon is a crude form of graphite, the substance used for pencil leads. It differs from graphite by having a random imperfect structure which is highly porous over a broad range of pore sizes from visible cracks and crevices to molecular dimensions. The graphite structure gives the carbon it's very large surface area which allows the carbon to adsorb a wide range of compounds. Activated carbon can have a surface of greater than 1000 m2 g. This means 5g of activated carbon can have...

Sample pointSample point

Configuration of column scale-up tests. It is also preferred where suspended solids create a high pressure drop, or dissolved gases create bubbles in the carbon bed. For a downflow or percolation system, an influent line should be installed at the top of the column, with an effluent at the bottom. To prevent the column from draining during operation, the effluent line from the last column should extend from the bottom of the column to above the top of the column. This will keep the...

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Ecology The study of all aspects of how organisms interact with each other and or their environment. Ecosystem Groupings of various organisms interacting with each other and their environment. E-coli Escherichia coli - one of the non-pathogenic coliform organisms used to indicate the presence of pathogenic bacteria in water. Effective area The total area of the porous medium exposed to flow in a filter element. Efficiency The ability, expressed as a percent, of a filter to remove specified...

The Sludge Pasteurization Process

Filter Press Sludge Treatment

This process is really sludge disinfection. Its aim is the destruction or inactivation of pathogenic organisms in the sludge. Destruction is defined as the physical disruption or disintegration of a pathogenic organism, while Inactivation is defined as the removal of a pathogen's ability to infect. In the United States procedures to reduce the number of pathogenic organisms are a requirement before sale of sludge or sludge-containing products to the public as a soil conditioner, or before...

The Pressure Leaf Filter

Diagram Agitated Nutsche Filter Dryer

This device is similar to a plate-and-frame filter press but the whole plate assembly is also housed in a tank or pressure vessel. This design allows higher pressures to be used, and also allows the filtration operation to be done more efficiently in many applications. There are two basic configurations, namely a horizontal plate and a vertical pressure leaf filter. Horizontal plate pressure filters were commonly applied to the fine chemical process industries such as antibiotics , pesticides...

Vacuum Filtration

We have already discussed this important technology in Chapter 5, but a review may be helpful in placing its importance to sludge processing into perspective. The vacuum filter for dewatering sludge is a drum over which is laid the filtering medium consisting of a cloth of cotton, wool, nylon, dynel, fiber glass or plastic, or a stainless steel mesh, or a double layer of stainless steel coil springs. The drum with horizontal axis is set in a tank with about one quarter of the drum submerged in...

Air Flotation Systems

Air flotation is one of the oldest methods for the removal of solids, oil amp grease and fibrous materials from wastewater. Suspended solids and oil amp grease removals as high as 99 can be attained with these processes. Air flotation is simply the production of microscopic air bubbles, which enhance the natural tendency of some materials to float by carrying wastewater contaminants to the surface of the tank for removal by mechanical skimming. Many commercially available units are packaged...

It Makes Sense To Select A Filter Press

Of When a very low moisture content is required for thermal cake drying or incineration. rar When high f ltrate clarity is required for polishing applications. rar When good cake release assisted by squeezing is required. y When the cake is disposed as land fill for spreading with a bulldozer provided it is hard enough to carry its weight. When large filtration areas are required in a limited space. The shuttle shifter moves the plates one by one towards the follower and the cake discharges....

Stabilization Via Aerobic Digestion

Aerobic digestion is an extension of the activated sludge aeration process whereby waste primary and secondary sludge are continually aerated for long periods of time. In aerobic digestion the microorganisms extend into the endogenous respiration phase. This is a phase where materials previously stored by the cell are oxidized, with a reduction in the biologically degradable organic matter. This organic matter, from the sludge cells is oxidized to carbon dioxide, water and ammonia. The ammonia...