How to Select Coagulation Equipment
Coagulation equipment is used to promote the destabilization and initial aggregation (flocculation) of finely divided, suspended solids by the application of a magnetic field, the addition of a coagulant, or a biological process.
What is Coagulation?
Coagulation is a process in which a soluble liquid becomes insoluble due to the application of an electric charge, a chemical reaction, or a biological process. This application causes components in the liquid to group together and form colloids, resulting in thickening or curdling. Milk and blood are common examples of products that coagulate due to the presence of biological factors such as bacteria and tissue. Coagulation equipment used for environmental, industrial, and medical applications does not normally implement a biological process but instead induces coagulation through chemicals or electric charge.
Types of Coagulation Equipment
Coagulation equipment has two main areas of use, the medical industry and the wastewater treatment industry.
In the wastewater treatment industry, coagulation is induced to remove contaminants from water. This process is carried out either by electrocoagulation or through chemical means.
- Electrocoagulation uses electricity to induce coagulation. Electric charge is dispersed through a solution and reduces colloid charge, causing the particles to become suspended in the water. Electrocoagulators are becoming more common in industry based on decreasing energy costs and ever-present wastewater treatment needs. They are used to treat wastewater containing foodstuff waste, oil waste, dyes, pulp and paper waste, mining and metal processing waste, mechanical polishing waste, and organic matter from landfill leachates.
- Chemical coagulation uses chemicals such as aluminum sulfate and poly aluminum chloride (PAC) to neutralize charges in a solution and encourage flocculation (clumping or binding together of particles). These chemicals, known as coagulants, are added and stirred vigorously into the solution. The equipment used to distribute and mix the chemicals vary based on the type of application and scale of the system.
In the medical field, coagulators are used for patient treatment in order to encourage blood clotting and also to destroy harmful tissue.
- Coagulation analyzers provide physicians with hemostasis (the process of stopping bleeding) test results from patients. They are used as point-of-care (POC) testing devices in cardiothoracic surgical suites and cardiac catheterization laboratories. Clinicians use the results from coagulation analyzer tests to monitor the effectiveness of heparin therapy, which is an anticoagulation therapy used during cardiopulmonary bypass (CPB) surgery, angioplasty, hemodialysis, and other clinical procedures.
- Electrocautery equipment is used by different types of surgeons in order to stop bleeding and providing hemostasis. An example of a hemostasis instrument is the hemostatic scalpel blade, which is a type of cutting and coagulating thermal scalpel blade. This type of coagulation equipment is designed to maintain the clean cutting characteristics of a traditional steel scalpel while simultaneously sealing blood vessels to provide hemostasis. Another example of a hemostasis instrument, a hemostasis valve, is used for catheters and comprises an elastomeric partition valve secured in housing.
Selecting Coagulation Equipment
Selecting a coagulator depends largely on the type of process and application for which it is being used. In treating wastewater, a coagulator must be fit to the size of the system it is treating and must also use techniques (either electrocoagulation or chemical coagulants) that are both cost-effective and treatment-effective for the process. An analysis of the chemistry in the wastewater will determine the type of materials necessary for designing the equipment as well as those needed as coagulants. For medical processes, tools and equipment are specific to the type of medical procedure being implemented.