AFI = Molecular Weight of Fluoride/Total Molecular Weight of Chemical * (100) Feed Rate, lbs/day = (Dosage, mg/L)(Flow, MGD)(8.34, lbs/gal) (Fluoride Solution, as a decimal)(Purity, as a decimal) Feed Rate, gpd = Feed Rate, lbs/day Chemical Solution, lbs/gal Feed Dose, mg/L = Desired Dose, mg/L – Actual Concentration, mg/L
- Chemical used, lbs per day = Flow rate, MGD x chemical dosage, mg/L x 8.34 lbs per gallon.
- Chemical, lbs/day = (Flow rate, MGD)(chemical dosage, mg/L)(8.34 lbs/gal)
- Chemical dosage, mg/L = (Chemical, lbs/day)/(Flow rate, MGD)(8.34 lbs/gal)
What is chemical dosing in water treatment?
Thermax water treatment technologies have a proven track record in providing innovative and successfully installed water treatment plants for various industries. Chemical dosing is the adding of chemicals into water/fluid or sludge to achieve required conditioning.
Why do we need chemical dosing calculator?
Therefore authors developed dosing calculator software as a tool for chemical dosing calculation in water Industry to support plant operators. In this paper, authors described the chemical dosing software for design and development of chemical dosing calculator. …
How do you properly dose chemicals in a waste stream?
The key to proper chemical dosing seems to lie in accurate measurement, both of the exact, up-to-the-minute needs of a waste stream, as well as the precise amount of chemicals being added to it.
How much do chemicals cost a wastewater plant?
And even if operators avoid a mistaken chemical reaction when overcompensating with chemicals, they are certainly throwing money away with every unnecessary addition. An estimate of a plant processing 100,000 cubic meters of wastewater per day put the total cost of chemicals at $21,000, about 6 percent of that plant’s average continual costs.
What is chemical dosing in water treatment?
Chemical dosing is the adding of chemicals into water/fluid or sludge to achieve required conditioning. This would make the treatment effective by various mechanisms such as charge neutralisation, settling of solids etc.
What is dosing in water supply?
Dosing involves tuning the levels of chemicals included to a batch or process stream to maintain a set concentration. This is accomplished by constantly monitoring the process using on-line instrumentation that automatically controls chemical dosing to guarantee levels are maintained without over- or under-dosing.
How does a chemical dosing system work?
A chemical dosing system is a facility for automated injection of reagents into a wastewater network for the control of septicity and odour emissions. These systems are typically used at pump stations, sewer manholes, and rising mains. However, they can be installed any place where odour containment is required.
What are the chemicals used in water treatment?
The most commonly used chemicals for water treatment process are:Algicide.Chlorine.Chlorine dioxide.Muriatic acid.Soda ash or Sodium bicarbonate.
What is chemical dosing in chilled water system?
Chemical treatment (or dosing): Proprietary (like NALCOOL) or generic chemicals (like Sodium Silicate, Sodium Nitrite, and Sodium Sulfite) compositions are used to prevent the chiller system from corrosion, scaling, fouling and microbiological growth.
What is the purpose of dosing?
Dosing generally applies to feeding chemicals or medicines when used in small quantities. For medicines the term dose is generally used. In the case of inanimate objects the word dosing is typical.
Which pumps are commonly used for chemical dosing?
Gear pumps, piston pumps, peristaltic pumps, and diaphragm type pumps are all available pumps to consider when injecting chemicals.
What are chemical dosing pumps?
Chemical dosing pumps are compact, positive displacement pumps that are designed to pump an extremely accurate flow rate of chemicals or other substances into a water or gas stream.
What is dosing equipment?
DOSING DEVICES. Metering devices are intended for bulk and small dose of powder and liquid products. With quality machines pack up to 1.5 liters per dose. The machine control is the control system with touch screen with 100 presets.
Why are chemicals used for water treatment?
They are typically used to remove harmful substances, such as ozone, hydrogen peroxide, chlorine, and biological contaminants, from wastewater. Coupled with aeration, these chemicals bond to suspended compounds to reduce them to component parts that can settle out of the water and be flocculated and filtered.
Why is it important to correctly measure the chemicals used in water treatment plants?
Additionally, if we're using them in water treatment plants, we want to make sure that our water is safe to drink. And so if we use to like too high or too low concentration of these chemicals, if they're not measured correctly, then our water could not be safe to drink. And so it's important.
What is chemical treatment?
Chemical treatment (of hazardous waste) refers to the treatment methods that are used to effect the complete breakdown of hazardous waste into non-toxic gases or, more frequently, to modify the chemical properties of the waste, for example, through reduction of water solubility or neutralisation of acidity or ...
Molybdate Method
The molybdate method is the most accurate way to determine a system's volume and can be used equally well in open or closed recirculating systems. In this method, a known amount of molybdate (molybdenum) is added to the system. The increase in molybdenum is measured, and the system water volume then is calculated.
Salt Method
In the salt method, a known amount of salt that will temporarily increase the chloride concentration by 50 to 100 ppm is added to the system. The increase is determined, and the system water volume is calculated. The temporary increase in chlorides will not harm the open system; however, this method might not be suitable for closed systems.
Solid Geometry Method
The solid geometry method involves measuring the dimensions of the tower sump or basin to determine the cubic feet of volume, plus measuring the lengths and diameters of the system piping. To follow this method:
Successful Water Treatment
In any chemical water treatment program, knowing the cooling water system's volume can be crucial. Simply guessing is not good enough; use the wrong dose of chemicals, and you could compromise the operation of your equipment.
Links
Ernie Appelhans is cooling water product manager of Garratt-Callahan Co., Burlingame, Calif., a water treatment solutions provider to the process cooling and other industries. For more information, call (650) 697-5811; visit www.g-c.com; or e-mail [email protected].
Chemical Metering, Dosing & Transfer of Fluids
As a fluid management process, wastewater treatment is heavily dependent on the transfer, metering and dosing of chemicals using various forms of pumping solutions. Throughout the process, a variety of technologies can be used to move, combine and separate fluids.
Coagulation & Flocculation
Once the wastewater is balanced, it needs to be separated to effectively remove the waste component and recycle the carrier water.
Water Disinfection
Water that has been balanced, separated and filtered to this point still requires a chemical additive to sanitize and disinfect it. Peristaltic-style pumps and double diaphragm pumps may be used in these steps to bulk-transfer the chemical into batches or dose the ingredient directly into the line.
Chemical Additives
A final step in the municipal process is the addition of chemicals for consumption or use downstream. The most common of these additives are fluoride or sodium chloride, depending on locality and water use.
What is Chemical Dosing?
Chemical dosing is the process of treating wastewater with chemicals like iron, aluminum, and even some salts to remove high levels of chemical content present in it. This chemical dosing is done in controlled amounts to remove the undesirable elements from wastewater and to make it usable again.
How Does It Work?
As a first step, the operators at industrial wastewater treatment systems identify the chemicals that get dissolved in the water and create a report based on their findings. This report helps the wastewater plant operators to determine the right chemicals that should be dosed to make the water potable again.
What Does the System Look Like?
The chemical dosing system will depend on many aspects such as location, availability of space, nature of chemicals, size of the plant, and more. In general, though, there will be at least two chemical tanks for holding the chemicals to account for repairs maintenance.
What is chemical dosing?
Chemical dosing is the adding of chemicals into water/fluid or sludge to achieve required conditioning. This would make the treatment effective by various mechanisms such as charge neutralisation, settling of solids etc.
What is Thermax water treatment?
Thermax is a leader in delivering water treatment plants for the diverse needs of industries. With 50 years of experience in designing, building and managing the construction of water treatment projects we create and implement tailored or standardised industrial water treatment solutions.
What are surfactants in wastewater?
Surfactants are among the most widely disseminated xenobiotics that contribute significantly to the pollution profile of sewage and wastewaters of all kinds. Among the currently employed chemical unit processes in the treatment of wastewaters, coagulation-flocculation has received considerable attention for yielding high pollutant removal efficiency. Jar-test experiments are employed in order to determine the optimum conditions for the removal of surfactants, COD and turbidity in terms of effective dosage, and pH control. Treatment with FeCl3 proved to be effective in a pH range between 7 and 9. The process is very effective in the reduction of surfactants and COD, the removals are 99 and 88 % respectively, and increased BOD5/COD index from 0.17 to 0.41. In addition to precipitation coagulation process, adsorptive micellar flocculation mechanism seems contribute to the removal of surfactants and organic matters from this rejection.
Why is water important?
Water has always been an important and life-sustaining drink to human and is essential to the survival of all organisms. The water industries are responsible for producing safe drinking water for people nation wide. Various chemicals like alum, poly electrolytes are required to mix with turbid natural water for removing solid waste material ...
Problems with overdosing or underdosing
The costs associated with underdosing are fairly self-evident. A failure to introduce enough chemicals to keep wastewater quality within regulatory limits can lead to exorbitant fines, operational mandates and irrevocable hits to an operation’s reputation.
The tools for balance
With equally problematic outcomes stemming from overdosing and underdosing of effluent with chemicals, wastewater treatment operators must ask themselves how to find the right balance to treat adequately and cost-effectively. More and more are finding their solution on the cutting edge of measurement technology.
Molybdate Method
Salt Method
- Make an estimation of the system volume.
- Accurately measure the chloride concentration of the tower water. Call this “Chloride A.”
- Approximately 0.5 lb for every 1,000 gal of the estimated volume is needed to achieve a reasonable change in chlorides. Use ordinary table salt (not rock salt). A box of salt in the supermarket usu...
- Measure the amount of salt needed into a bucket by weighing 0.5 lb of salt for every 1,000 gal of estimated v…
- Make an estimation of the system volume.
- Accurately measure the chloride concentration of the tower water. Call this “Chloride A.”
- Approximately 0.5 lb for every 1,000 gal of the estimated volume is needed to achieve a reasonable change in chlorides. Use ordinary table salt (not rock salt). A box of salt in the supermarket usu...
- Measure the amount of salt needed into a bucket by weighing 0.5 lb of salt for every 1,000 gal of estimated volume, using one 26-oz box for every 3,000 gal.
Solid Geometry Method
- Calculate the volume (in gallons) of water in the basin by measuring the dimensions -- length (L), width (W) and depth (D) -- of water in the basin in feet and use the following equation: Basin Vol...
- Calculate the volume (in gallons) of water in the various system pipes. If the pipe length (L, in feet) and diameter (D, in inches) are known, use the following equation to get the volume of water...
- Add the basin and pipe volumes together to get the total volume of water in the system.
Sidebar: Guesstimating Volume
- For a system having only one cooling or pump loop, add a detectable material such as a dye or foam producer (such as a detergent) to the basin, then time how long it takes for the material to appea...
- No direct relationship exists between recirculation rate and volume. However, you can get a ballpark volume figure by multiplying the recirculation rate (gal/min) by 10.
- The same holds true for tonnage and volume, but try the factor of 30 gal/ton of refrigeration.
- For a system having only one cooling or pump loop, add a detectable material such as a dye or foam producer (such as a detergent) to the basin, then time how long it takes for the material to appea...
- No direct relationship exists between recirculation rate and volume. However, you can get a ballpark volume figure by multiplying the recirculation rate (gal/min) by 10.
- The same holds true for tonnage and volume, but try the factor of 30 gal/ton of refrigeration.
- Minimally, get a basin volume, then estimate a percentage (+10 percent, +25 percent, +50 percent, etc.) for the piping volume based on an observation of the plant size.