pH and ORP Analyzers

One of the primary applications for high purity water is for boiler feed water. The measurement of pure water pH can be one of the quickest indicators of process contamination in the production or distribution of pure water. Effective chemical treatment of the feed water is vital in maintaining the useful operating life and minimizing maintenance costs of the boiler.

The proliferation of microorganisms and the resultant formation of slime is a problem which commonly occurs in aqueous systems. Problematic slime producing microbes may include bacteria, fungi and/or algae. Slime deposits typically occur in many industrial aqueous systems including cooling water systems, pulp and paper mill systems, petroleum operations, clay and pigment slurries, recreational water systems, air washer systems, decorative fountains, food, beverage, and industrial process pasteurizers, sweetwater systems, gas scrubber systems, latex systems, industrial lubricants, cutting fluids, etc.

There are a number of suppliers of oil and fat products used for edible purposes. These products include, but are not limited to olive oil, peanut oil, soybean oil, sunflower oil, lard, shortening, butter, and margarine. The raw materials for these products include animal by-products, fleshy fruits (palm and olive), and oilseeds. 

Industry:Food and Beverage

Control of sodium chloride (NaCl) concentration at a salt dissolver where solid salt is dissolved in water, is highly important because of the electrolysis efficiency. A conventional way of measuring the concentration of supersaturated NaCl solution had been performed by using non-contact type sensors (e.g., γ-ray density meter) since NaCl, impurities, and precipitates are in the solution.

In the manufacturing process of Pharmaceutical, Chemical and Food & Beverage industries, the cleaning and sterilization of tanks and piping are done with various cleaning solutions, fresh or hot water and steam after manufacturing products. Clean-In-Place (CIP) is the system designed for automatic cleaning and disinfecting.

Caustic soda and hydrochloric acid, produced in electrolyzer plants, are fundamental materials used in varieties of industries; chemicals, pharmaceuticals, petrol-chemicals, pulp and papers, etc. Profit is the result of the effective production with minimized running / maintenance cost. Proper control of the process brings you stabilized quality of products with the vast operational profit.

The control of the world's water resource is arguably one of the most important issues. Water demand from industry and domestic users is set to rise throughout the industrialized world. Yokogawa has been applying minimized maintenance measurement systems.

Problems at the wet end of a paper machine can rarely be corrected down stream. That is why monitoring and controlling pH in pulp stock is critical to the paper making process. Essentially, at every stage in the manufacture of paper, correct pH values play a vital role. Variations in the pH value at the head box have a negative effect on the quality of the paper produced.

Cyanide-bearing wastewater from mining and electroplating facilities and certain types of chemical plants is toxic and must be treated by oxidation with chlorine or chloride to bring the cyanide concentration within regulatory limits.

Industry:Electrical and Electronics

The treatment of wastewater from pulp and paper plants is a serious environmental concern. Yokogawa's submersion holder with an ultrasonic+air-jet cleaner (customized product) can reduce the manual cleaning frequency to just once every one or two months.

Industry:Pulp & Paper

Continuous technology improvement is ongoing in the pulp & paper industry to obtain the best possible performance. Problems at the wet end (stock preparation) can rarely be corrected downstream. That is why monitoring and controlling pH in pulp stock is critical to the paper making process. Essentially, at every stage in the manufacture of paper, correct pH values play a vital role.

Reverse osmosis (RO) is a separation process that uses pressure to force a solution through a membrane that retains the solute on one side and allows the pure solvent to pass to the other side. More formally, it is the process of forcing a solvent from a region of high solute concentration through a membrane to a region of low solute concentration by applying a pressure in excess of the osmotic pressure.

Sour Water is the wastewater that is produced from atmospheric and vacuum crude columns at refineries. Hydrogen sulfide and ammonia are typical components in sour water that need to be removed before the water can be reused elsewhere in the plant. Removal of these components is done by sending the sour water from the process to a stripping tower where heat, in the form of steam, is applied.

Power plant boiler houses designed to burn coal or high sulfur oil are required by Federal and State pollution regulations to "scrub" (remove) sulfur dioxide from flue gasses to meet emission limits. SO₂ in flue gasses is known to be harmful to the environment, as it is one contributor to the formation of acid rain. pH control is critical for the proper functioning of the scrubber system.

For control of batch neutralization, a pH measurement coupled with a timer-controlled chemical feed scheme provides very satisfactory results.

This system can be adapted for either acid waste or alkaline waste neutralization.

Wet scrubbers are used in utilities, paper mills, and chemical plants to remove sulfur dioxide (SO₂) and other pollutants from gas streams. Undesirable pollutants are removed by contacting the gases with an aqueous solution or slurry containing a sorbent. The most common sorbents are lime, Ca(OH)₂, and limestone, CaCO₃. 

Wastes have been considered to be a serious worldwide environmental problem in recent years. Because of increasing pollution, these wastes should be treated. However, industrial wastes can contain a number of valuable organic components. Recovery of these components is important economically. Using conventional distillation techniques, the separation of acetic acid and water is both impractical and uneconomical, because it often requires large number of trays and a high reflux ratio. In practice special techniques are used depending on the concentration of acetic acid. 

Sodium chlorate is an inorganic compound with the chemical formula NaClO3. It is a white crystalline powder that is readily soluble in water. It is hygroscopic. It decomposes above 300 °C to release oxygen and leave sodium chloride. Several hundred million tons are produced annually, mainly for applications in bleaching paper.

In flue gas desulfurization systems that use magnesium hydroxide (Mg(OH)₂) slurry, the consumption of the desulfurization agent (Mg(OH)₂) is controlled by using online pH analyzers. A great concern in the pH measurement is heavy staining of the pH electrodes by the Mg(OH)₂ slurry. To ensure accurate measurement, frequent cleaning of the electrodes with an acid is required, adding to both maintenance workload and cost.

Industry:Chemical, Power

In stable dispersion of fine particles is the pre-requisite for the selective flocculation technique involving separation of ultra-fine valuable particles from the gangue. Among mineral processing techniques selective flocculation technique is known to have outstanding potential of capturing the particles of particular mineral in slurry of mixed mineral system by selective adsorption of water soluble polymers known as flocculants.

Brewery is facility to produce beer. Breweries process is the manufacturing process of beer, which is a fermented beverage with low alcohol content made from various types of grain. Wheat, maize and other grains can be used for this. Brewing process starts from malted barley that is to form a mash by milling and mixing with hot water. The malt starches are converted to sugars during this process. This sugar rich water is then strained through the bottom of the mash and will be called as "wort". Then the wort will be brought to boil by bringing to the brew kettle. For bitterness or aroma hops are to be added at different times during the boil. Then the wort is cooled and aerated. And brewers yeast is added for fermentation. From the sweet wort the yeast produces carbon dioxide, alcohol and other byproducts. The GREEN BEER undergoes maturation after fermentation. Filtaration and carbonation are the last steps. Finally the beer will be stay in holding tank until it is bottled or kegged.

After extraction from sugar cane or sugar beets, juice must be purified to remove the many other organics and minerals that accompany it.
 The processing to accomplish this is heavily dependent on reliable pH measurement and control as illustrated.

Wastewater from electroplating facilities and certain types of chemical plants contains toxic forms of hexavalent chromium such as chromate and dichromate. The hexavalent chromium in this wastewater must be reduced before the water can be discharged. This requires a two-step process: hexavalent chromium (CR₆) is reduced to trivalent chromium (CR₃); and CR₃ is precipitated as chromium hydroxide.

Industry:Electrical and Electronics

Fish perform all their bodily functions in water. Because fish are totally dependent upon water to breathe, feed and grow, excrete wastes, maintain a salt balance, and reproduce, understanding the physical and chemical qualities of water is critical to successful aquaculture. To a great extent water determines the success or failure of an aquaculture operation.

In the manufacturing of Glass-Fiber wool for insulation a melt of a material such as glass is inductively heated at a stage intermediate an initial liquefying stage and a refining stage. Induction heating is the process of heating an electrically conducting object (usually a metal) by electromagnetic induction, where eddy currents are generated within the metal and resistance leads to Joule heating of the metal.

The level of dissolved oxygen is critical to the quality and consistency of any brew. Too little dissolved oxygen results in the fermentation step of the process will lead to: off flavors (e.g. poor removal of diacetyl and acetaldehyde), poor yeast crop in terms of quantity and vitality, and low ester and alcohol production. 

The detectors used to perform dissolved oxygen (DO) measurement in oxidation ditch type sewage treatment plants tend to become dirty quickly and require frequent cleaning. It has been d ifficult to remedy this problem inexpensively. One solution that significantly reduces the sensor maintenance workload is the use of float holders.

Many Ethanol plants running today are using a combination style pH electrode with a non-flowing reference to measure pH in the Mash Slurry transfer line from the Mash slurry mix tank to cook. The Mash is being pumped out of the Mash Slurry tank is at approximately 180 °F and 40 to 60 psig.

United States Pharmacopoeia (USP) is the governing body responsible for issuing guidelines for the pharmaceutical industry. Implementing these guidelines is required for companies that bring drugs to the US market. This means that USP is important to all pharmaceutical companies, period.

Optimizing four key factors will decrease pH sensor costs and optimize process control and overall plant efficiency.

To facilitate the accurate measurement of pH, and its presentation as a scale, a range of "standard liquids" or "buffer solutions" are used. These liquids, whose constituents are accurately defined, have known stable values. Although in the preceding text the relationship to hydrogen ions has been made, research has shown, that the activity of hydroxonium ions (H₃0⁺) is more relevant.