How to fit a scale inhibitor. If your data define a complete sigmoidal curve it is best to fit the entire curve and let Prism fit the Top and Bottom. BWTs Combi- Care works by introducing a small amount of food grade polyphosphate into the water feed sequestering the calcium in the water and preventing it from forming scale on the heat exchanger.
Do scale inhibitors work with water conditioners?
Most scale inhibitors tend to be magnetic or electric systems with several electrolytic systems also available. These devices lack key benefits that water conditioners offer, such as the ‘soft water lifestyle benefits’.
Where to discuss scale inhibitor fitting?
Discuss Scale Inhibitor Fitting in the Plumbing Forum | Plumbing Advice area at PlumbersForums.net Not open for further replies.
What is scale inhibition and how is it achieved?
Scale inhibition can be achieved either by adding substances that react with potential scale forming substances so that from the point of view of thermodynamics the stable region is reached or by adding substances that suppress crystal growth. Conventional scale inhibitors are hydrophilic, i.e., they dissolve in water.
Why do scale inhibitors fail to work?
Since scale inhibitors have to act at the interface between solid scale and water, it is not surprising that their performance can be upset by the presence of other surface active chemicals that compete for the same interface.
How do scale inhibitors work?
How do they work? There are several different mechanisms which inhibitors use to reduce scale. Many purport to use similar methodologies to water conditioners. Most scale inhibitors tend to be magnetic or electric systems with several electrolytic systems also available.
What is scale inhibitor?
A scale inhibitor is a device designed to reduce the amount of limescale formed in hard water areas. These devices are usually compact and designed to protect single pieces of equipment such as a boiler. But there appear to be many of these systems available.
Is a scale inhibitor good for limescale?
If you want an effective whole house solution to your limescale issues, then an inhibitor is not likely to be the best solution. But if you aren’t troubled by the many problems limescale causes and simply want to ensure that your boiler is kept running efficiently with minimal expenditure then scale inhibitors fit the bill.
What is a thermodynamic inhibitor?
For example, for scale inhibition of barium sulfate, common chemicals are ethylenediamine tetraacetic acid (EDTA) and nitrilo triacetic acid. The solubility of calcium carbonate can be influenced by varying the pH or the partial pressure of carbon dioxide ( ). The solubility increases with decreasing pH and increasing partial pressure of , and it decreases with temperature.
Why are scale inhibitors used?
Scale inhibitors are most often used as a prevention technique to reduce the scaling risks in near wellbore location and wellbore (Shaughnessy and Kline, 1983).
What additives are used in fracture fluids?
Trace amounts of metal chelate-forming additives, which are used in fracture fluids, have been shown to have a debilitating effect on the performance of widely used barium sulfate scale inhibitors. Ethylenediamine tetraacetic acid, citric acid, and gluconic acid render some scale inhibitors, such as phosphonates, polycarboxylates, and phosphate esters, completely ineffective at concentrations as low as 0.1 mg l – 1. Such low concentrations may be expected to return from formation stimulation treatments for many months and would appear to jeopardize any scale inhibitor program in place.
How do scale inhibitors interfere with nucleation?
Some scale inhibitors can interfere with the nucleation process by diffusing in the bulk liquid to reach the ion clusters either in the liquid or on a solid substrate. These inhibitor ions should be of a sufficiently large size to disrupt the scaling ion clustering and prevent further growth of existing clusters to the critical size where crystallites would form. A good nucleation inhibitor ion needs to be of a critical size but still be able to diffuse in the water at an acceptable rate.
How to use scale inhibitor?
First a dilute solution of scale inhibitor with surfactant is applied to clean and cool the near wellbore. This step is followed by a high concentration solution of the scale inhibitor—the pill, followed by a low concentration solution of inhibitor which is applied to move the pill away from the near wellbore, radially outward to a distance into the near wellbore which is designed to give maximum squeeze life.
Which polymer is more effective at high temperatures?
Phosphonates are maximally effective at high temperatures whereas sulfonated polymers are maximally effective at low temperatures  . Copolymers that contain both phosphonate and sulfonate moieties can produce an enhanced scale inhibition over a range of temperatures.
Why is nucleation not promoted?
Due to adsorption effects, the inhibitor molecules occupy the nucleation sites which are preferred by the scale-forming molecules. Thus, crystals cannot find active places to adhere to the surface and, therefore, crystal nucleation is not promoted.
What are Corrosion and Scale Inhibitors?
Corrosion and scale inhibitors are tailored chemicals that delay or prevent corrosion and/or scale formation when added in small concentrations in water that would normally create scale deposits. A day-to-day example is prevention of limescale in washing machines. Corrosion is the deterioration and loss of a material and its critical properties due to chemical, electrochemical and other reactions of the exposed material surface with the surrounding environment. In 1936, Professor Langelier’s research best described water corrosion or scale deposition tendency. He gave conditions in which water is balanced with calcium carbonate, making it possible to predict the likelihood of a given water to either precipitate or dissolve calcium carbonate. Scale inhibitors or antiscalants are generally organic compounds containing sulphonate, phosphate, or carboxylic acid functional groups and chelating agents such as carbon, alum and zeolites that sequester and neutralize a particular ion that may be formed.
What are the different types of scale inhibitors?
Scale inhibitors can coarsely be classified as organic and inorganic. The inorganic types include condensed phosphate, such as poly (metaphosphate)s or phosphate salts. Suitable organic scale inhibitors available are poly (acrylic) acid (PAA), phosphinocarboxylic acid, sulfonated polymers, and phosphonates. Phosphonates are maximally effective at high temperatures whereas sulfonated polymers are maximally effective at low temperatures. Copolymers that contain both phosphonate and sulfonate moieties can produce an enhanced scale inhibition over a range of temperatures.
Are environmental regulations, health and safety concerns or potential profit loss a concern right now?
Thermodynamic inhibitors – complexing and chelating agents, suitable for specific scales.
What are some of the theories behind the mechanism of action?
The precise mechanism for scale inhibitors is not completely understood but the following are some of the theories. Scale inhibitors may adsorb onto the surface of the scale crystals just as they start to form . The inhibitors are large molecules that can envelop these microcrystals and hinder further growth. This is the primary mechanism. Many oil field chemicals are designed to operate at oil/water, liquid/gas, or solid/liquid interfaces. Since scale inhibitors must act at the interface between solid scale and water, it is not surprising that their performance can be upset by the presence of other surface-active chemicals that compete for the same interface. Before deployment it is important to examine in laboratory tests the performance of a scale inhibitor in the presence of other oil field chemicals. These chemicals function by delaying the growth of scale crystals, the inhibitor must be present before the onset of precipitation. Suspended solids also known as nonadherent scales are not acceptable. This suggests two basic rules in applying scale inhibitors:
Is there selection criteria of corrosion and scale inhibitors?
Compatibility – The scale inhibitor must not interfere nor be affected by other chemicals such as oxygen scavengers, corrosion inhibitors and biocides.
Are there limitations of corrosion and scale inhibitors?
Inorganic corrosion and scale inhibitors suffer hydrolysis and can precipitate as calcium phosphates because of temperature, pH, solution quality, concentration, phosphate type and presence of some enzymes.
How does a corrosion inhibitor work?
The effectiveness of a corrosion inhibitor depends on fluid composition, quantity of water, and flow regime. Inhibitors can work by adsorbing themselves on the metal’s surface and forming a protective film.
threeof New Member
I have a lovely high quality Flomasta ‘Electolytic Scale Inhibitor’ … I assume this is fitted straight after the stop cock ?
It has been said that after passing water through an ‘inhibitor’ in to a kettle and then boiling the water, some of the scale is kept in suspension.
threeof New Member
Its being fitted with a magnetite trap, to help protect a combi boiler, so guess it could go on the flow to just that ?? although I read its best to fit one straight after the stop cock, but as you say – its ‘wholesome’, although I would read into that that the water does not come from a rat and pidgeon infested loft water tank (ie feeds straight in under water pressure) – but stand to be corrected..
G&W Plumbing & Heating Active Member
Scale reducers work when 1 mtr from heat source, they shrink scale particles on an atomic scale so they pass through and build up slower. Reducer not eliminator
threeof New Member
G&W – 1mt !, I have installed mine 5 meters before the boiler, and one meter before the kitchen sink tap (ie directly after the incoming stop cock).
G&W Plumbing & Heating Active Member
Scale reducers don’t soften water, they reduce scale build up on an element or heat exchanger where the water is heated.