Table of Contents
What do you mean by flocculation?
Flocculation is a process by which a chemical coagulant added to the water acts to facilitate bonding between particles, creating larger aggregates which are easier to separate.
What is flocculation Vdrl?
The Venereal Disease Research Laboratories (VDRL) test is a flocculation test that detects antibodies produced by treponemal infection. These antibodies, called reagins, are produced upon the invasion of host tissues. The rapid plasma reagin test is a refinement of the VDRL.
What is VDRL test negative?
A negative test is normal. It means that no antibodies to syphilis have been seen in your blood sample. The screening test is most likely to be positive in the secondary and latent stages of syphilis. This test may give a false-negative result during early- and late-stage syphilis.
What is an example of a flocculant?
Flocculation and coagulation treatment chemicals are used in effluent wastewater water treatment processes for solids removal, water clarification, lime softening, sludge thickening, and solids dewatering. Examples of ChemTreat coagulation products include aluminum salts, iron salts, and polyelectrolytes.
What is flocculant for?
Used in a wide range of industries and applications, flocculants help to remove suspended solids from wastewater by aggregating contaminants into flakes or “flocs” that float to the surface of the water or settle at the bottom. They can also be used for lime softening, sludge thickening, and solids dehydration.
How long is Vdrl positive?
The VDRL and RPR, respectively, are reactive in 78 percent and 86 percent of patients with primary syphilis. 8 They become positive within approximately four to six weeks after infection or one to three weeks after the appearance of the primary lesion.
What is serological test?
An antibody test looks for the presence of antibodies, which are specific proteins made in response to infections. Antibodies are typically detected in the blood of people who are tested after infection; they show an immune response to the infection.
Is alum a coagulant or flocculant?
To accomplish this, the water is treated with aluminum sulfate, commonly called alum, which serves as a flocculant. Raw water often holds tiny suspended particles that are very difficult for a filter to catch. Alum causes them to clump together so that they can settle out of the water or be easily trapped by a filter.
What is the difference between coagulation and flocculation?
Coagulation: Particles that aggregate with themselves e.g. by the influence of a change in pH. Flocculation: Particles that aggregate by the use of polymers that binds them together.
What is the purpose of flocculation?
Effect on Turbidity As with coagulation, the purpose of flocculation is not to directly reduce turbidity or suspended solids, but to prepare the solids for subsequent removal. Flocculation reduces the number of suspended solids particles as smaller particles combine to form larger ones.
What chemicals are used in flocculation?
Chemicals (coagulants) are added to the water to bring the nonsettling particles together into larger, heavier masses of solids called floc. Aluminum sulfate (alum) is the most common coagulant used for water purification. Other chemicals, such as ferric sulfate or sodium aluminate, may also be used.
What is the principle of RPR test?
The principle of the RPR test is a flocculation reaction between the RPR antigen and the reagin. The reaction can be seen macroscopically on the test slide as clumping of the carbon particles.
How is Vdrl transmitted?
Syphilis is most likely to spread during oral, anal, or vaginal sexual activity. People rarely pass the bacteria on through kissing. The first sign is a painless sore on either the genitals, rectum, mouth, or another part of the skin. Some people do not notice the sore, as it does not cause pain.
What is flocculation wastewater?
Flocculation is a water treatment process where solids form larger clusters, or flocs, to be removed from water. This process can happen spontaneously, or with the help of chemical agents. One of the requirements for treated water leaving wastewater plants is the removal of suspended solids.
What is the principle of syphilis test?
Test Principle The Syphilis Test is a qualitative membrane device based immunoassay for the detection of TP antibodies (IgG and IgM) in whole blood, serum or plasma. In this test procedure, recombinant Syphilis antigen is immobilized in the test line region of the device.
What is flocculation serology?
Flocculation is a physical process of contact and adhesions wherein the aggregates form larger-size clusters called flocs being excluded from suspension. A: Direct agglutination reaction where antibodies recognize and establish links with antigens forming aggregates.
Is flocculant hazardous?
This material is not considered hazardous under the OSHA Hazard Communication Standard (HazCom 2012). None known. General advice : No hazards which require special first aid measures. If inhaled : If breathed in, move person into fresh air.
Why Tpha test is done?
Treponema pallidum hemagglutination commonly known as TPHA is diagnostic test used to detect the dissolved amount of antibodies in the serum sample of a patient against the causative agents of syphilis. To be precise the TPHA test helps in the detection of Palladium antibodies via the hemagglutination method.
What is flocculant made of?
The aluminum-based flocculants include aluminum sulfate, aluminum chloride, sodium aluminate, aluminum chlorohydrate, and polyaluminum chloride. The iron-based flocculants include ferric chloride, ferric sulfate, ferrous sulfate, and ferric chloride sulfate [15, 69].
What is slide flocculation test?
The V. D. R. L. slide flocculation test was employed as the routine serologic test for syphilis. The cardiolipin microflocculation antigen and buffered diluent were prepared and standardized by the Army Medical Service Graduate School.
How is flocculation prevented?
Design contact times for flocculation range from 15 or 20 minutes to an hour or more, and flocculation requires careful attention to the mixing velocity and amount of mix energy. To prevent floc from tearing apart or shearing, the mixing velocity and energy are usually tapered off as the size of floc increases.
