Army raises age limit, extends deadline for eligible OCS applicants | Article. The Department of the Army has raised the age limit to 3. Active Component, in- service Soldiers to apply for Officer Candidate School at the upcoming July OCS selection panel. Applicants must possess baccalaureate degree or higher. The application deadline is June 2. The customary age limit of 3. AC applicants [set forth in Army Regulation 3. In Service OCS Program,] reflects the old requirement that, when they become commissioned officers, those without baccalaureate degrees will pursue their bachelor's degrees to completion. However, now that a bachelor's degree is a requirement to apply for OCS, the age limit has been adjusted for the July panel since most in- service Soldiers are over 3. Clifford M. Preetorius, the OCS program manager in the Officer Accessions Branch, which falls under the Officer Personnel Management Directorate at the U. S. Army Human Resources Command. The next HQDA OCS Selection Panel is scheduled for July 2. Aug. 2. The original deadline for packet submission of May 2. June 2. 1 to give more applicants the opportunity to complete local application procedures. Packets may only be submitted to the Army Knowledge Online, or AKO, folder. How Can Army Enlisted Personnel Apply for OCS? by Brenda Scottsdale. The age limit for eligibility is 35. What Happens if an Army Reservist Goes on Active Duty? The Department of the Army has raised the age limit to 33 for eligible Active Component. Army extends deadline for Officer Candidate School applicants. but the RC age limit for OCS is already at 34. By ANDREA WALES U.S. Army Human Resources Command Public Affairs Office The Department of the Army has raised the age limit to 33 for eligible active component, in-service Soldiers to apply for Officer Candidate School at the. Dose anyone know what is the age limit for those just joining the Army to get in the OCS program? And what is the age limit for those already in the Army to go to OCS? Active Navy. baam111 · 8 years ago. 0. Soldiers must check their personnel file in i. PERMS, the Army's Interactive Personnel Electronic Records Management System, and have missing documents scanned in by their S- 1/personnel. HRC intends to release Selection Panel dates by MILPER Message in the near future. Army Officer Candidate School gives college graduates an opportunity to be leaders and officers for Active Duty or. Officer Candidate School (OCS). In order to qualify for Officer Candidate School as an active duty. Guard or Reserves-and age limit for OCS. Login or register to post comments; 1 reply Sat, 02/19/2011 - 23:32 Anonymous. What is. Then see a Regular Army Recruiter. He can enlist Reserves as well as Active Army. Active Duty Enlisted Basic Military Pay Charts … About.com; About Careers; US Military. The Army experimented with raising the age limit to age 42 for a brief period of time, but effective April 1st, 2011. To aid Soldiers and S- 1s in preparing packets and answering general questions, HRC officials plan to hold training and application sessions through Defense Connect Online, or DCO, online seminars. Dates of the webinars will be released with the MILPER Message announcing fiscal year 2. Selection Panel dates."The Army is looking for high- speed, forward- thinking Soldiers with unimpeachable character," Preetorius said. Those are the ones we want to apply to OCS." News of the age- limit increase doesn't affect prospective OCS applicants who aren't in the Army's Active Component: Reserve Component applications, which are submitted through the U. S. Army Reserve Command's Army Reserve Careers Division, are paneled through HRC, but the RC age limit for OCS is already at 3. AR 1. 40- 5. 0)]. The U. S. Army Recruiting Command has a USAREC panel process for civilians who apply for Army OCS or Army Reserve OCS (AR 6. Army National Guard recruiters should be the initial point of contact for National Guard Soldiers interested in OCS or civilians interested in joining the National Guard to attend OCS [National Guard Regulation (NGR) 3. As a commissioned officer, you will encounter new challenges that will enhance your leadership abilities and enable you to inspire and motivate others," said Jon A. Banco, the interim chief of the Officer Accessions Branch at HRC OPMD. Seize this opportunity. Remember the June 2. AC enlisted Soldiers and warrant officers can find out how to apply to OCS by reading MILPER Message No. MILPER Message 1. MILPER Message No. Visit the HRC website at http: //www. Popular HRC Resources.".
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Fun Christmas Activities - Symbols, Stories, Games, Poetry, Rhymes, Plays, Coloring Pages, Word Searches, and Recitals. Shhhh.. Amazon Secret Sale ! Items are sorted by ages and categories. Includes Angry Birds, Legos, Barbie, Dora, Leapfrog Learn- to- Read, Webkinz, Transformers and more! Toys and Games - Once you get to the secret sale page, use the navigation on the left to find toys on sale by age or brand name. Cameras and Accessories - Once you get to the secret sale page, use the navigation on the left to find cameras on sale by brand name. Some great deals if you shop right! Fun Christmas Classroom Activities | Classroom Caboodle. Christmas classroom activities – specifically a school party – come just before a major school break, which can lend a laid- back, “take the afternoon off” air to the event. Christmas/December Classroom Ideas. printed on inkjet magnet sheets hide a treat for each December day before Christmas. Child Activities, Christmas Fun. Merry Christmas! This page has a selection of Christmas games and activities that can be used in an ESL Kids classroom. Some have specific teaching functions, others.You know what I’m going to say about that: resist the temptation! As with any elementary activity, a party that drags on for too long will inevitably degenerate into one of those not- so- fun activities that does not serve your team- building efforts well. Besides, a long party is not necessary. Let’s cover how to do it up right. But first… let’s recall the potential issues that some students may have with Christmas classroom activities. Accommodating differences. As discussed on the Halloween party page, if you work in a public school, the taxpayers are footing the bill for your salary and the entire district. Some of those taxpayers do not celebrate Christmas for a variety of religious or personal reasons, and they do not want their children to celebrate the holiday, either. That is why we have “winter” or “winter break” parties. Be certain it is not just a re- labeling; your fun holiday activities must revolve around winter themes, NOT traditional Christmas themes. It is simply the professional thing to do if you teach in a public school. And even a “winter” party may not be acceptable for those who do not celebrate any parties at all. Be sensitive; you may need to arrange for kids to go to other classrooms or get an excused absence if needed. But talk to parents first and don’t assume anything. What to give your students for Christmas. Ideas for Christmas classroom activities. The ideal plan is to work winter activities into your lesson plans for a couple of weeks in December, then have them culminate in an educational activity at the party. Winter is easy to tie to curriculum, even if you don’t normally get snow for the holidays in your part of the world. Let’s cover some ideas for both “way- too- much snow” and “snow- deprived” areas. The science of snow.
Study “Snowflake Bentley”…the man who first photographed snowflakes. Go to www. snowflakebentley. Read science articles on the crystalline structure of snow, and then cut out really fancy snowflakes for Christmas classroom activities at the party. Don’t cut out basic snowflakes when you can create amazing ones using Dave’s Snowflakes as a reference. He has collected over 4. Kids seriously love these! Video tips: standards- based snowflake fun. Other science angles. Consider building lesson plans around the following ideas: Animals that hibernate. Winter in the Northern Hemisphere vs. Southern Hemisphere. Major winter weather events (blizzards, ice storms, avalanches, etc.)Snow sports. All of these are in my winter products. Holiday activities galore! Winter party activity ideas. The winter party is a a quiet time, especially compared to the school Halloween party. Start by having the students enjoy a small cup of cocoa and a graham cracker while watching a science video about snow. If you are feeling jolly, lead them in a rendition of the carol “Let it Snow.”Then lead into the culminating project of your winter lesson plan – such as cutting out the snowflakes, as mentioned above. Another great idea, and one that produces a score- able piece of work, is to have the students write to a winter prompt. You might consider an all- day write (from notes to rough draft to finished copy). If you need more than a small winter snack to go with your Christmas classroom activities, keep the focus on healthy food (or at least not- too- unhealthy) while maintaining a winter theme. And for winter, the theme is “white as snow” of course! Consider these: Cauliflower with ranch dip. String cheese. Bananas. Applies with yogurt dip. Tofu squares(You know I’m kidding on the last one, right?)Think this might help someone? Share this article. More from Classroom Caboodle. Black. Berry Internet Service. The MTN BlackBerry Internet Service has been blocked on Android, PC and other devices. This post explains how to use the Airtel BIS to browse on ANY device instead. BlackBerry Internet Service provides business users of BlackBerry devices with Internet capabilities and virtual real-time delivery of email and messaging services. New Users You need to create an account to begin sending and receiving email on your BlackBerry® device. Please turn on your device and ensure that it is connected.
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Schools across the Southland have had to trim millions of dollars from their budgets, increasing class size, and cutting nursing, library and bus services. In some districts, funds also were cut for after- school activities such as band, pep squads, debate and sports teams, choral music, and the school newspaper and yearbook. When school districts are forced to trim, should they try to save extracurricular activities? Extracurricular activities are. It's difficult to justify cutting teachers and. In private schools extracurricular activities are an integral part of. SCHOOL FUNDING WOES -- EXTRACURRICULAR CUTS. along with other Neoga extracurricular activities. Area schools that participate in the Apollo include Mattoon. Schools across the Southland have had to trim millions of dollars from their budgets, increasing class size, and cutting nursing, library and bus services. In some. The Importance of Educators Involvement in Extracurricular. As schools continue to cut. Cutting extracurricular activities for the school budget may. Cutting to the bone: At a glance. Cutting extracurricular activities. For schools to succeed in the long run. 3 Cons of Extracurricular Activities. These are the reasons that make extracurricular activities a kind of disruption to students. 1. It adds to the Student’s Pressure. Transcript of Budget Cuts and Extracurricular Activities. Schools are at risk for cutting all sports and clubs Some schools dependent on philanthropy. Budget Cuts Put School Sports On Chopping Block. the most sensible extracurricular activity. the hue and cry that would go up if schools started. Kathy Klein, M ontebello Teachers Assn. I don't see any way of justifying cutting programs within school hours for programs outside of school hours. The community is much more willing to fund extracurricular activities, and in times of difficulty we have to call upon them to help. It's easier to find somebody who wants to put money into the football team than somebody who wants to put money into seventh- grade education. We have to fund the well- rounded base program first and then look for alternatives to fund the rest. You have to preserve the part that is in the school day first. If you can't afford to put out a school newspaper, then you just don't do that, but you can still teach journalism. You can still teach athletics. There's nothing that we've done in the Montebello School District that's wasted or extra or fluff. But we've gotten kind of spoiled. We're accustomed to the district paying for everything. Supt. Lee Eastwood, W hittier Union High School District If you've gotta spend a buck, you spend a buck on the core curriculum. Schools are in the knowledge business and that's got to be their focus: What funding is needed to result in the proper class load and teacher- pupil ratio? We've had to face those kinds of decisions in the last few years. You need to carry out those basic functions, and my priority would be the classroom. But it's a value thing that each school district goes through. In our district, we did not cut any of the base programs for the kids, athletically or academically. We cut administrators. We cut nurses. We cut ground crews. We cut back in certain supply areas and equipment, but not that much at the school level. We trimmed around the edges. But I wouldn't be as arrogant to say what I would do in another environment. Each district has its own values. Ellen Shin, Schurr High School student body president The benefits reaped from extracurricular activities honestly affect a lot more people on the whole than the jobs that were affected by the district cuts. It really pains me to say that. I'm upset that the Board of Education had to cut these jobs in the first place. But if a student just goes to school and studies, then there's no type of recreational outlet. It would produce a very narrow- minded student with only one perspective of how life is. Without extracurricular activities at school, there's no school spirit. There's no morale. They should be able to feel like a part of something, be a part of a team or look at the yearbook and say 'I was a part of that.' What's a high school without a football team? What's a high school without a yearbook? These are supposed to be our high school years, and they wanted to take all our memories away. Marilyn Larson, Long Beach Unified School District library spokeswoman I do not like to see instructional opportunities cut. I know those students in band and newspaper need a great deal. But the resources in the library are very important as well. Students who use the library might not be the ones who have a booster club to raise the issue for them. It's easy to rally around something that is more visible. The band is something that is certainly more visible than a student working on a term paper in the library and asking a librarian for assistance. This is not something that makes headlines, but it's very vital. It's the infrastructure that keeps the whole process of education supported. I wish people could see more of what's coming out of there. A library tends to be the first on the list to be cut. I don't think there's a librarian in the world who does not have those fears of losing a job just because of the economic situation in our state and in our nation. Practice for superlatives, nationalities, and directions. Glossary of ESL terms Home | Crosswords | Word Searches | Flash Cards |. Worksheets, crosswords, word searches, flashcards, lesson plans, and teaching activities for ESL classrooms. Hello. Could you tell me where the da-da-da is? Yes, the da-da-da is across the street from the City Park and next to the City Clinic.? English worksheets, lesson plans and other resources Hi. You may try referring to the lottery as an example: Tell your ss "I have bought a lottery ticket, but I will keep teaching you - I donj ´t think I will win the lottery."From here, you can proceed to explain that the possibility of winning the lottery is real, because you have bought the tickey; but the probability is extremely low, so they can count on you as their teacher to the end if the school year. Once they have understood the difference, you may then iontroduce the adequate modals to express each of the situations: "I may / might win the lottery tomorrow, as I have bought a ticket." - -> possibility "I won ´t win the lottery tomorrowm even though I have bought a ticket." - -> probability. Tohave your ss practise the difference, you can then ask them to build sentences about their lives expressing probability and possibility and read them to class, to see if theyr colleagues ´ reaction: "I might be get an excellent mark in the history test, but I probably won ´t, because I haven ´t studied much." I hope this helps. What is nonstopenglish.com? Nonstopenglish.com is a FREE English as a Second language (ESL) and English as a Foreign Language (EFL) activity website. ESL ReadingSmart offers students individualized, content-based instruction to develop English language proficiency with emphasis on literacy and academic language. Instructions: Study the map before you begin. Listen to the speaker giving directions to different places on the map by pressing the 'PLAY' link. Copyright Inte r Ed Co nsultants 200 3 CITY MAP Where is X? Can you tell me how to get to X (to the nearest x)? Go straight # blocks (lights). ESL Printables, the website where English Language teachers exchange resources: worksheets, lesson plans, activities, etc. Our collection is growing every day.DOCTYPE html PUBLIC "- //W3. C//DTD XHTML 1. 0 Transitional//EN". TR/xhtml. 1/DTD/xhtml. Generator" content="NReadability 1. Handheld. Friendly" content="true" /> Five Senses Crafts preschool and kindergarten activities. Free 5 senses crafts, five senses preschool activities, and printables Take your children on a nature walk. Encourage them to pay close attention to the things that they see, hear, smell, taste, and feel on the walk. Stop at various points along the way and invite volunteers to share what they sense. Explore Manal Maz's board 'Five Senses' on Pinterest, a visual bookmarking tool that helps you discover and save creative ideas | See more about Senses Activities, 5 Senses Activities and My Five Senses. Explore Highland Heritage Homeschool's board '5 Senses Activities & Printables' on Pinterest, a visual bookmarking tool that helps you discover and save creative ideas | See more about My Five Senses, Exploring and Kindergarten. The 5 Senses Worksheets. 5 Senses: Taste Matching. 5 Senses: Taste Matching. Updated on Apr 24, 2013. My Five Senses; activity. Have a Magnet Marathon! worksheet. 5 Senses: Touch Matching; Loading. THE FIVE SENSES A science teaching lesson on the five senses. Includes printable teaching worksheets and activity. Elementary Science five senses, sight, hearing, smell, touch, taste Learning Objective. Point out interesting sights, smells, and sounds as is appropriate. Halfway through the walk, stop and provide a healthful snack, such as raisins, pretzels, or fruit. View also our Twiggle Magazine 5 Senses Edition for more activities, crafts, recipes, and games. The Sense of Sight What’s Missing? Present children with a box of small objects such as a crayon, scissors, a pencil, an earring, a cookie cutter, etc. Let children select four or five items from the box. Put the items on the table. Have children close their eyes, and then remove one of the items. Have children open their eyes and ask them to tell you what the missing item is. Continue the game, changing the items. The Sense of Sound Sound Walk. Take a walk with children outside. Bring either a tape recorder or a notepad and record the sounds that you and the children hear (birds singing, wind blowing, etc). Have a discussion with children about the sounds they heard, and then let them mimic the sounds. The Sense of Smell. Scratch and Sniff Paint. Using ordinary poster paint and a very small amount of glue, add a few drops of essence to each color paint (you could color associate it if you wanted to: orange aroma with orange paint, apple with green paint etc.). Paint thick patches onto separate cards and let dry. Hang the cards up as a let children scratch the paint to smell the card. The Sense of Taste. Popcorn. Prepare popcorn for snack time. The five senses worksheets get your child to think about sight, hearing, touch, smell and taste. Use the five sense worksheets with your young scientist. Divide popped corn into three bowls. Season one bowl of popcorn with Parmesan cheese, one bowl with salt, and one bowl with sugar. Let children taste the three different flavored popcorns and identify the substance on the popcorn in each bowl. Make a chart to define the favorite popcorn flavor. The Sense of Touch. Surprise Bag. Place several familiar objects in a sack. Have each child reach in to pull out an object, and using only the sense of touch, name the object before pulling it out. For example, the sack could contain several of the following items: spoon, fork, small ball, toothbrush, cup, small plate, pencil, small book, marble, cotton ball, paper clip, sock, shoe lace, magnifying glass, jump rope, block from a Lego set, candle, etc.). Five Senses Rhyme: I Use My Five Senses(Tune: The Farmer in the Dell)Author Unknown. I use my eyes to see, I use my eyes to see, And when I want to see a star, I use my eyes to see. I use my nose to smell, I use my nose to smell, And when I want to smell a flower, I use my nose to smell. 5 Senses Crafts and Five Senses Preschool Activities. Our five senses allow us to enjoy the world around us—the taste of our food. literacy activity. The Five Senses word wall. The Five Senses coloring pages. The. I use my tongue to taste, I use my tongue to taste, And when I want to taste a peach, I use my tongue to taste. I use my ears to hear, I use my ears to hear, And when I want to hear a bird, I use my ears to hear. I use my hands to touch, I use my hands to touch, And when I want to touch a cat, I use my hands to touch. The Story of Ferdinand (Puffin Storytime)Amazing Animal Senses. Explain to children that animals have the same five senses as we do, but some animals have senses that we don’t have or more heightened senses. Bats To avoid obstacles and catch food while flying, bats emit ultrasonic squeaks and interpret the echo the sound waves make after bouncing off objects in the environment. This is called “echolocation,” and it is also used by dolphins to navigate murky waters. Boas and Vipers Temperature- sensitive organs located between the eyes and nostrils of boas and pit vipers allow these snakes to sense the body heat of their prey. There is one located on each side of the snake’s head enabling the animals to perceive depth and strike with deadly accuracy even in complete darkness. Rats Most rats have poor vision, but they make up for it with the “whiskers” on their snouts. They use the long hairs, also called “vibrissae,” in the same way that blind people use canes. By whisking the hairs across objects they come across, rats and other rodents form mental pictures of their surroundings. Owls An owl can see a mouse moving over 1. Rabbits Some animals, like rabbits, have their eyes on the sides of their heads, letting them see to either side and even behind themselves. That's because they spend most of their waking hours browsing for food; being able to see in all directions guards against other animals trying to sneak up on them. Dissolved organic carbon (DOC) is a broad classification for organic molecules of varied origin and composition within aquatic systems. The 'dissolved' fraction of. Activated carbon filters - Lenntech. For pesticide removal only at averal occurence at ppb levels, lifetime of an activated carbon bed can be up to 1. For natural organic matter or oil and grease, bed renewal can vary from few weeks to few years. Please send us your water analysis. Activated Carbon Organic Matter In SoilActivated Carbon Filters | Activated Carbon Water Treatment. Activated carbon filters are generally employed in the process of removing organic compounds and/or extracting free chlorine from water, thereby making the water suitable for discharge or use in manufacturing processes. Eliminating organics in potable water, such as humic and fulvic acid, prevents chlorine in the water from chemically reacting with the acids and forming trihalomethanes, a class of known carcinogens. Activated Carbon (AC) filtration, as with any water treatment method, is not capable of removing every possible type of contaminant. For example, sodium, microbes, fluoride, and nitrates cannot be removed with AC filtration. Water softening also cannot be achieved with AC filters. In addition, heavy metals, such as lead, can only be removed with a very specific kind of activated carbon water treatment, which is typically used only in residential point- of- use filters. Coconut shells and coal (anthracite or bituminous) are both organic sources of activated carbon. Carbon forms when an organic source is burned in an environment without oxygen. This process leaves only about 3. Prior to being used for water treatment, the organic mass must then be “activated.” The process of activation opens up the carbon’s massive number of pores and further drives off unwanted molecules. The open pores are what allow the carbon to capture contaminants, known as "adsorption". The rate of adsorption for a surface area of a just one pound of AC is equal to 6. Activated Carbon Organic Matter For LawnsThere are two main activation methods: Steam Activation – Steam activation is carried out using steam at temperatures of between 8. C and 1. 00. 0°C. At these temperatures an instant Water- Gas reaction occurs, gasifying the carbonized material. Air is then introduced to burn out the gasses, without burning the carbon. This process produces a graded, screened and de- dusted form of activated carbon. Carbon activated by steam generally has a fine pore structure, ideal for adsorbing both liquid phase and vapor phase compounds. Chemical Activation – With chemical activation the carbon is first filled with a powerful dehydrating agent, typically a paste form of phosphoric acid (P2. O5) or zinc chloride (Zn. Cl. 2). The paste is heated to temperatures between 5. C and 8. 00°C to activate the carbon. Chemical activation produces activated carbon with a very open pore structure, making it more suitable for adsorbing large molecules. How it Works. Activated carbon water treatment is basically used for two water treatment purposes and each work in totally different ways. Chlorine Removal: Activated carbon may be used to remove chlorine with little degradation or damage to the carbon. Dechlorination occurs rapidly and flow rates are typically high. However, this process requires an extensive amount of surface area, and organics in the water will eventually fill up and block the pores of the carbon. Ultimately, the AC filter will need to be replaced as its ability to dechlorinate the water will slowly decline. Spent carbon can be re- activated; however, re- activated filters should only be used in waste- water treatment applications. One advantage to using AC is its low operating cost and virtual “fail safe” operation once installed. One disadvantage is that as the chlorine is removed from the topmost layer of the media, the AC provides a damp environment ideal for the growth and proliferation of bacteria. Bacteria can cause problems in medical applications, or when using carbon as a pretreatment to reverse osmosis. Removal of Organic Matter: As water passes through an activated carbon filter, organic particles and chemicals are trapped inside through a process known “adsorption”. The adsorption process depends upon 5 key factors: 1) physical properties of the activated carbon (surface area and pore size distribution); 2) the chemical makeup of the carbon source (amount of hydrogen and oxygen); 3) the chemical makeup and concentration of the contaminant; 4) water p. H and temperature; and 5) the length of time the water is exposed to the activated carbon filter (called empty bed contact time or EBCT). Additional considerations for organics removal are discussed below: Physical Properties: Pore size and distribution have the greatest impact on the effectiveness of AC filtration. The best filtration occurs when carbon pores are barely large enough to allow for the adsorption of contaminants (Figure 1). The type of contaminants an AC filter attracts will depend on the pore size of the filter, which varies based on the type of carbon used and the activation method. AC filters tend to work best for removing organic chemicals with larger molecules. Figure 1. Molecular screening in the micropores of an activated carbon filter. G. L. Culp and R. L. Culp)Chemical Properties: The surface of an activated carbon filter may also interact chemically with organic molecules. Electrical forces between the AC surface and the chemical nature of some contaminants may result in ion exchange or adsorption. The activation process determines, to a large extent, the chemical properties of the AC filter, making the filter attractive to various contaminants. Different activation processes will yield activated carbon with different chemical properties. For example, AC that has the least amount of oxygen in pore surfaces will absorb chloroform the best. Contaminant Properties: Activated Carbon is best for use in filtering out large organic molecules. AC and organic molecules are similar materials, which means they will tend to associate with each other. This means organic chemicals will have a stronger tendency to associate with the AC filter rather than remaining dissolved in water. The less soluble organic molecules are, the more likely they are to be adsorbed. Smaller organic molecules fit the smallest pores and are held the tightest. For pesticide removal only at averal occurence at ppb levels, lifetime of an activated carbon bed can be up to 10 years. For natural organic matter or oil and grease. WaterProfessionals® provides activated carbon filters for water treatment. Remove free chlorine and/or organic compounds with activated carbon water treatment. Granular activated carbon (GAC) has been used extensively for the removal of dissolved organics from drinking water. In the early seventies, it was reported that. Carbon Activated manufactures and delivers high quality standard and specialist Activated Carbons Worldwide. Concentration: The adsorption process can be affected by the concentration of organic contaminants. For example, with chloroform removal one AC filter may be more effective than another at filtering high concentrations of contaminants, and less effective at filtering low concentration of contaminants. Consult with the manufacturer to determine how an activated carbon filter will perform at different concentration levels for a specific chemical. Water Temperature and p. H: The rate of adsorption will usually be higher at lower temperatures and p. H levels. Chemical reactions and chemical forms are closely related to water temperature and p. H. In most cases, organic chemicals are more adsorbable as temperatures and p. H levels decrease. Length of Exposure: The length of time in which the contaminant is in contact with the AC filter also influences the adsorption process – the longer the length of contact, the greater the number of contaminants that will be removed. A greater amount of active carbon and a slower flow rate will improve the effectiveness of the filtration process. Bed depth and flow rate are critical design parameters. Carbon filtration is often engineered to provide a specified residence time of water in contact with the carbon bed, referred to as empty bed contact time or EBCT. Filtration Equipment. Activated carbon filters are similar to those used in multi- media filtration, except without the air scour step in the backwash process. Since certain organics require an extended exposure time to the filter to be removed, higher filter vessel sideshells may be used to provide deeper carbon beds for extended reaction times. Carbon beds should be backwashed to help remove trapped silt, prevent packing and head loss, and to remove carbon fines produced by friction between granules. As described above, there are a host of variables that must be considered in designing a filtration system and selecting the best carbon for the application. The Water. Professionals® have years of experience to help in design such systems. Contact us for additional information. Back to Process Water. |
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