Gas separation – With nonliquid cleaning means for separating media – Solid agent cleaning member movingly contacts apparatus
Patent
1991-11-18
1993-01-26
Hart, Charles
Gas separation
With nonliquid cleaning means for separating media
Solid agent cleaning member movingly contacts apparatus
55237, 55238, 55398, B01D 4706
Patent
active
051819449
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a wet blaster/wet washer for wetting a gas and for drying the excess liquid, which wet washer comprises a chamber provided with a central impeller and a central inlet channel having one or more liquid feeds.
Several different possibilities of realizing gas cleaning are known. The most usual way is to use a simple cyclone separator, or a vortex separator. Only coarser dust particles can be removed by means of this method. Very fine particles (<10 .mu.m) penetrate through the cyclone, as the specific weight of the dust to be separated corresponds to the specific weight of silicate minerals (ca. 2 g/cm.sup.3). Therefore, the use of cyclones is not very practical in normal operating conditions. They are, however, commonly used as preseparators, in which case the final separation is realized with other separators by utilizing either a day filter or a wet washer.
In a dry filter, the dust separation occurs by using a filter cloth. In this case, the dust particles are screened into the cloth and the penetrated gas is clean. The tightness of the cloth, i.e. the size of the fiber openings of the cloth, determines the size of the particles leaving the filter. It is quite usual that the mesh size of the filter cloth is less than 3 .mu.m. The size of the dust particles penetrating through the cloth then in practice remains less than 2 .mu.m. Even tighter clothes are used, but when the tightness increases, more and more energy is needed as a so-called pressure loss to allow the gas to penetrate through. The filter structure is termed according to how the filter is placed, e.g. as a pocket, hose, plate, etc.
A name and a principle is also given to the dry filter according to how the filter cloth is cleaned of the filtered dust. Currently, the newest filters are cleaned with pressure impulses, which refer to a vigorous and sudden pressure shock against the filter cloth and generally further against the flow direction of the gas to be cleaned.
A third way of removing solid dust particles from gases is to use an electric filter, in which the impurity particles of the gas are charged by the action of electric contact elements in a high electric field either positively or negatively. It is important and essential that the gas with its dust particles continues its travel and is subjected to the area of influence of another, opposite electric field, an electrode, whereby a charged dust particle clings to this electrode and thus leaves the gas flow. In this manner, even large quantities of dust particles can be removed from the gas, the efficiency being relatively good. The result is often satisfactory. Electric filters are expensive and they are also intended for larger quantities of gas. Thus, electric filters are generally used for cleaning process gases, whereby the separated or recovered dust can be extremely valuable.
For example a device according to the FI patent application 1704/71 is previously known, in which a relatively coarse material is separated from a gas flow, whereby a plate construction directs an air flow and the material therein along an outer wall via an opening on the outer wall at the lower end together with a small amount of transfer gas (ca. 10%). The remaining air leaves through the middle section of the separator. This known solution is intended for the separation of the coarse part of a granulous material, whereby the air travelled with the material via the outer wall is cleaned in a separate collecting container. The remaining air (ca. 90%) leaves via a space between a guiding spiral and a pipe located outside an outlet channel into the outlet channel. This gas contains a fine dust, which then has to be separated with a separate filter.
In the case of the dry filters described above it is common that they cannot remove e.g. detrimental gas components from the gases. The gases are often too hot especially for dry filters. Therefore, the gases have to be cooled or dilute, which causes additional costs and essentially increases the amount of gases. A wet washer can receive
REFERENCES:
patent: 3468614 (1969-09-01), Nilsson
patent: 3538684 (1970-11-01), Esterhoy et al.
patent: 3960524 (1976-06-01), Cumpston
patent: 4243396 (1981-01-01), Cronenberg
patent: 4478616 (1984-10-01), Jarvenpaa
patent: 4963329 (1990-10-01), Burgess et al.
Derwent Abstract No. 86-237450/36.
Hart Charles
Wiser Oy
LandOfFree
Wet blaster/wet washer does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Wet blaster/wet washer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Wet blaster/wet washer will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1410463