Gravity filtration is a method of filtering impurities from solutions by using gravity to pull liquid through a filter. The two main kinds of filtration used in laboratories are gravity and vacuum/suction. Gravity filtration is often used in chemical laboratories to filter precipitates from precipitation reactions as well as drying agents, inadmissible side items, or remaining reactants. While it can also be used to separate out strong products, vacuum filtration is more commonly used for this purpose. [1]
The process of removing suspended matter contains two steps: transport and attachment. [2] This mode occurs when particles move to another place through the filter paper.
Gravity filtration is an easy way to remove solid impurities or the precipitation from an organic liquid. The impurity is trapped in the filter. Gravity filtration can collect any insoluble solid. [3]
Early in human history, people obtained clear water from muddy rivers or lakes by digging holes in sandy banks to a depth below the waterline of the river or lake. The sand filtered the water and clear water fills the hole; this method was used to reform cities and purify urban waters. [4]
In farming, people used gravity filtration to let water from higher areas flow to lower areas through filters. In this way, sand and small stones filter impurities producing clear water.
In Asia, people pump water from wells and put it into a jar with a small hole at the bottom. The jar is filled with small stones and the hole is covered with layers of gauze.
Filtration is commonly used to filter out solutions contain solids or insoluble precipitation. [5]
The solution is poured through a piece of filter paper folded into a cone in a glass funnel. Solids (or flocs) remain on the filter paper while the filtered solution is caught by a flask under the funnel. [6] If a large volume of solution is filtered, the filter paper will need to be changed in order to prevent clogging. [7]
In many laboratories, gravity filtration is used to filter out solids to determine reaction yield. Several experimental errors need to be taken into account.
Some precipitated solid remains on the filter paper or in the funnel. In this case, a gap appears between the product yield and the measured yield.
If the precipitated solid is not dried thoroughly, excess fluid influences the experimental results. The actual yield of precipitation may then appear larger than the theoretical yield.
Incorrect use of filter paper may influence the filtration. Additionally, damaging the filter paper can allow small bits of precipitated solids to pass through the filter. [8]
A variety of filtration operations were tested with seawater for dissolving high concentrations of dimethylsulfoniopropionate. [9]
These filters contain three stages: flocculation, clarification and filtration.
Typical rapid gravity filters contain filter tanks made of coated or stainless steel or aluminum. Influent flows fall through the filter and are captured by the underdrain. The filter media removes particles from the water. It usually has 3 layers: anthracite coal, silica sand and gravel. [10]
This approach is effective for removing impurities and uses less cleaning time, lowering cost.
The project was to remove parasites and other contaminants such as lead. The project used multi-hole filters with diameters that allow water to flow by gravity. [11]
These filters are used for industry applications. The filter lets the fluid stream pass through the media to remain or filter out impurities. It can support large volumes.
Some gravity filter systems in the chemistry industry can remove chlorine and other organics or remove iron and heavy sediments or sand. [12]
Liquid is removed from a gas stream by coalescers in a single stage. The elements enter with the flow and then pass through the distributor. This is a primary separation device that can remove particles and then coalesce the cartridges in an inside-to-out direction. In this case, the liquids pass through the structure of the filter and then drain from the vessel. [13]
This filter is an open sand filter system used for water treatment in low budget environments. It can suit a variety of pressure-controlled backwashing. This filter is an automatic gravity filter that uses different pressures and backwashes the system with an injector. The system has no controls. The filters have no moving parts and no pumps. The backwashing water is held in a tank below the filter. [14]
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Filtration is a physical process that separates solid matter and fluid from a mixture.
Filtration is a physical separation process that separates solid matter and fluid from a mixture using a filter medium that has a complex structure through which only the fluid can pass. Solid particles that cannot pass through the filter medium are described as oversize and the fluid that passes through is called the filtrate. Oversize particles may form a filter cake on top of the filter and may also block the filter lattice, preventing the fluid phase from crossing the filter, known as blinding. The size of the largest particles that can successfully pass through a filter is called the effective pore size of that filter. The separation of solid and fluid is imperfect; solids will be contaminated with some fluid and filtrate will contain fine particles. Filtration occurs both in nature and in engineered systems; there are biological, geological, and industrial forms.
Filter paper is a semi-permeable paper barrier placed perpendicular to a liquid or air flow. It is used to separate fine solid particles from liquids or gases.
Water purification is the process of removing undesirable chemicals, biological contaminants, suspended solids, and gases from water. The goal is to produce water that is fit for specific purposes. Most water is purified and disinfected for human consumption, but water purification may also be carried out for a variety of other purposes, including medical, pharmacological, chemical, and industrial applications. The history of water purification includes a wide variety of methods. The methods used include physical processes such as filtration, sedimentation, and distillation; biological processes such as slow sand filters or biologically active carbon; chemical processes such as flocculation and chlorination; and the use of electromagnetic radiation such as ultraviolet light.
Water treatment is any process that improves the quality of water to make it appropriate for a specific end-use. The end use may be drinking, industrial water supply, irrigation, river flow maintenance, water recreation or many other uses, including being safely returned to the environment. Water treatment removes contaminants and undesirable components, or reduces their concentration so that the water becomes fit for its desired end-use. This treatment is crucial to human health and allows humans to benefit from both drinking and irrigation use.
In an aqueous solution, precipitation is the "sedimentation of a solid material from a liquid solution". The solid formed is called the precipitate. In case of an inorganic chemical reaction leading to precipitation, the chemical reagent causing the solid to form is called the precipitant.
A media filter is a type of filter that uses a bed of sand, peat, shredded tires, foam, crushed glass, geo-textile fabric, anthracite, crushed granite or other material to filter water for drinking, swimming pools, aquaculture, irrigation, stormwater management, oil and gas operations, and other applications.
A water filter removes impurities by lowering contamination of water using a fine physical barrier, a chemical process, or a biological process. Filters cleanse water to different extents, for purposes such as: providing agricultural irrigation, accessible drinking water, public and private aquariums, and the safe use of ponds and swimming pools.
Sand filters are used as a step in the water treatment process of water purification.
In terms of water treatment, including water purification and sewage treatment, backwashing refers to pumping water backwards through the filters media, sometimes including intermittent use of compressed air during the process. Backwashing is a form of preventive maintenance so that the filter media can be reused. In water treatment plants, backwashing can be an automated process that is run by local programmable logic controllers (PLCs). The backwash cycle is triggered after a set time interval, when the filter effluent turbidity is greater than a treatment guideline or when the differential pressure across the filter exceeds a set value.
A dust collector is a system used to enhance the quality of air released from industrial and commercial processes by collecting dust and other impurities from air or gas. Designed to handle high-volume dust loads, a dust collector system consists of a blower, dust filter, a filter-cleaning system, and a dust receptacle or dust removal system. It is distinguished from air purifiers, which use disposable filters to remove dust.
The rapid sand filter or rapid gravity filter is a type of filter used in water purification and is commonly used in municipal drinking water facilities as part of a multiple-stage treatment system. These systems are complex and expensive to operate and maintain, and therefore less suitable for small communities and developing nations.
An oil filter is a filter designed to remove contaminants from engine oil, transmission oil, lubricating oil, or hydraulic oil. Their chief use is in internal-combustion engines for motor vehicles, powered aircraft, railway locomotives, ships and boats, and static engines such as generators and pumps. Other vehicle hydraulic systems, such as those in automatic transmissions and power steering, are often equipped with an oil filter. Gas turbine engines, such as those on jet aircraft, also require the use of oil filters. Oil filters are used in many different types of hydraulic machinery. The oil industry itself employs filters for oil production, oil pumping, and oil recycling. Modern engine oil filters tend to be "full-flow" (inline) or "bypass".
In chemical engineering, biochemical engineering and protein purification, cross-flow filtration is a type of filtration. Cross-flow filtration is different from dead-end filtration in which the feed is passed through a membrane or bed, the solids being trapped in the filter and the filtrate being released at the other end. Cross-flow filtration gets its name because the majority of the feed flow travels tangentially across the surface of the filter, rather than into the filter. The principal advantage of this is that the filter cake is substantially washed away during the filtration process, increasing the length of time that a filter unit can be operational. It can be a continuous process, unlike batch-wise dead-end filtration.
Swimming pool sanitation is the process of ensuring healthy conditions in swimming pools. Proper sanitation is needed to maintain the visual clarity of water and to prevent the transmission of infectious waterborne diseases.
Depth filters are filters that use a porous filtration medium to retain particles throughout the medium, rather than just on the surface of the medium. Depth filtration, typified by multiple porous layers with depth, is used to capture the solid contaminants from the liquid phase. These filters are commonly used when the fluid to be filtered contains a high load of particles because, relative to other types of filters, they can retain a large mass of particles before becoming clogged.
In chemistry, recrystallization is a technique used to purify chemicals. By dissolving a mixture of a compound and impurities in an appropriate solvent, either the desired compound or impurities can be removed from the solution, leaving the other behind. It is named for the crystals often formed when the compound precipitates out. Alternatively, recrystallization can refer to the natural growth of larger ice crystals at the expense of smaller ones.
Spa filters work continuously to keep debris and sediments from the water in a spa pool.
Oil purification removes oil contaminants in order to prolong oil service life.
Diatomaceous earth (DE) filtration is a special filtration process that removes particles from liquids as it passes through a layer of fossilized remains of microscopic water organism called diatoms. These diatoms are mined from diatomite deposits which are located along the Earth's surface as they have accumulated in sediment of open and moving bodies of water. Obtained diatomaceous earth is then purified using acid leaching or liquid-liquid extraction in order for it to be used in any form of application. The process of D.E. filtration is composed of three main stages: pre-coating, body feed, and cleaning.
