Method of production of flexographic plates by means of laser engraving
FIELD: technological processes.
SUBSTANCE: in method of flexographic plates production by direct laser engraving, gaseous decomposition products or products made of separate particles (7) generated in the process of engraving are caught with the help of suction device (4) and exhausted gas flow saturated with decomposition products is purified with the help of combination of filter (5) with solid filtering material and filter (6) with buffer unit and oxidising stage.
EFFECT: increases efficiency of gases purification.
8 cl, 6 dwg
The present invention relates to a method for producing flexographic printing forms direct laser engraving, in which the catch formed during the etching gas or consisting of separate particles of the decomposition products with the help of the suction device and clean saturated with the products of decomposition of the flow of exhaust gas using a combination of at least one filter with a particulate filter material and at least one cleaning stage, working on the principle of oxidation.
In direct laser engraving for producing flexographic printing forms printing relief laser engrave directly into the relief-forming layer of a flexographic printing element. The next stage of manifestation, as a conventional method of manufacturing a flexographic printing forms are no longer required. In principle, the production of flexographic printing forms direct laser engraving is known, for example, from US 5259311, WO 93/23252, WO 02/49842, WO 02/76739 or WO 02/83418.
In direct laser engraving the relief layer absorbs the laser radiation in such proportions that in those places where it is exposed to a laser beam of sufficient intensity, this layer is removed or at least exfoliate. This layer, respectively its components while evaporate and/or dissolved, so that PR is the products of their decomposition in the form of hot gases, fumes, smoke, aerosols or fine particles are removed from the layer. Usually used for engraving, in particular, the IR high power lasers, such as, for example, CO2lasers or Nd-YAG lasers. Suitable devices for engraving flexographic printing plates are disclosed, for example, in EP 1162315 and EP 1162316.
The typical thickness of the relief layer of the flexographic printing forms is usually in the range from 0.5 to 7 mm Napechatala depressions in the terrain have a depth in the bitmap area of at least 0.03 mm, other negative elements considerably more in the case of thick printed forms can be set up to 3 mm. Thus, in direct laser engraving is necessary to remove the laser large quantities of material. Already at the depth of the engraving within only 0.5 to 0.7 mm and with degree of material removal on average, 70% removed approximately 500 g of material at 1 m2printed form. In this respect, direct laser engraving is very different from other methods of the manufacture of printing plates, in which lasers are used only to describe the mask, and the actual production of the printing form still occurs through the processes of leaching, respectively manifestations. This kind is described by lasers masks typically have a thickness of only a few micrometers. The poet is the number you want to delete a material in this case is usually only 2 to 6 g/m 2.
Under the influence of laser radiation material relatiobship layer, first, evaporates, and secondly, is split into more or less large debris. Thus, on the one hand, there are adhesive organic aerosols with particle diameters typically less than 1 μm and, on the other hand - volatile organic compounds. In the case of volatile components we can talk about the different products of pyrolysis, as well as on the specific monomers, the resulting thermal depolymerization of the polymer components. Modern flexographic printing plates usually contain binders that include as Monomeric structural elements of styrene and butadiene and/or isoprene. We can talk about, for example, block-polymers of styrene-butadiene or styrene-isoprene type. Other components of flexo printing forms, such as, for example, oil plasticizers may include butadiene or isoprene as structural elements. As a result of depolymerization binders and plasticizers in the engraving of flexo printing forms on the basis of polystyrene-polyisoprene-polystyrene (SIS) or polystyrene-polybutadiene-polystyrene (SBS) rubber formed, among other decomposition products, large quantities of styrene and isoprene or butadiene. More detailed information is relatively formed decomposition products and the treatment they are given, for example, in the work of: Martin Goede, "Entstehung und Minderung der Schadstoffemissionen bei der Laserstrahlbearbeitung von Polymerwerkstoffen", Fortschritt-Berichte VDI, Reihe 5, Nr.587, Düsseldorf, VDI-Verlag, 2000.
Laser apparatus for cutting or engraving usually contains a suction device, which can sense the resulting decomposition products. Examples of laser head with integrated exhaust given in EP-330565 or WO 99/38643. The presence of such suction prevents contamination as equipment and workplace decomposition products.
When laser engraving of flexo printing forms produced off-gas flow, which, along with podsosonnim air contains large quantities of gaseous products, in particular styrene, butadiene and/or isoprene, as well as large quantities of adhesive aerosols. Decomposition products may not be simply released into the environment, therefore, the exhaust gas must be cleaned to ensure compliance with the rules for the maximum allowable content of impurities. For example, in accordance with the German technical manual ″Air″ exhaust gas must not contain more than 1 mg of butadiene in 1 m3.
In "WLB Wasser, Luft und Boden", Bd.7/8, 2001 S.69 ff. (VF Online Medien GmbH & Co. KG, Mainz) describes a system for cleaning exhaust air during thermal processing of polymer materials, which is the Oh combination of two different filters. In one filter with particulate filter material is first separated aerosols with the use of an inert excipients and directly behind it absorbed gaseous components in the absorber with a layer of activated charcoal.
This method of cleaning exhaust gas, however, not economical when used for laser engraving of flexo printing forms. Butadiene and isoprene are very poorly absorbed by the activated carbon.
The maximum saturation of activated carbon butadiene is at room temperature only about 4% (mass.). Therefore, the capacity of one of the filling of activated carbon very soon exhausted.
Further, when laser engraving of flexo printing forms very intense suction that the engraving to prevent re-deposition on the print surface shape formed very sticky aerosols. Re-deposition of aerosols on the surface is highly undesirable, as deposited aerosols strongly impair obtained by printing the image. Therefore, after the engraving on the case that will be repeated precipitation of the polymer, the surface of the printing form must be further cleaned with a suitable cleaner, such as conventional flexographic wymiany means. As printing plates in flexographic ymywha tool swell, then print the form before application must again be dried thoroughly. This procedure usually lasts from two to three hours and is extremely undesirable, as it again negates the benefits in time in comparison with conventional treatment.
For dust aerosols to prevent their re-deposition typically requires a minimum of 0.5 m3of air per gram of decomposition products. Therefore, the exhaust gas in the direct laser engraving of flexographic printing plates characterized by a very high volumetric flow rates with low saturation. Gaseous products contained in the gas flow only in very small concentrations, and the adsorption-desorption equilibrium on charcoal is unfavorable for the complete precipitation of butadiene. Therefore, it requires very large filters of activated charcoal, and the cost of removal and/or reactivation of activated carbon is very high. Zeolites adsorb butadiene and isoprene though better than activated carbon, however, they are considerably more expensive than activated carbon. In addition, still have to bear the cost of their reactivation and/or recycling.
Further it should be noted that when talking about preferences for direct laser engraving of flexographic printing plates, the mean is not large, the installation of industrial scale. Moreover, the engraving of the printing form is produced near the end user and decentralized either in the printing or in zincography, that is, in a typical small enterprises or the enterprises of medium size. These installations are not in continuous and periodic mode. With the establishment and operation of installations for purification of exhaust gas in the direct laser engraving of flexo printing forms should also take into account these boundary conditions.
In accordance with the foregoing, was created a method of manufacturing a flexographic printing forms direct laser engraving, by etching terrain suitable for laser engraving of flexographic printing element with the use of laser equipment that includes at least:
- the unit cylindrical support for flexo printing elements in which a cylindrical bearing can be installed with the possibility of its rotation,
- drive unit for rotation of the cylinder,
- laser head emitting at least one laser beam, and the laser head, as well as installation the unit is installed coaxially with the cylindrical support with the possibility of displacement relative to each other, and
- suction device
which way as the source material used is suitable the La laser engravable flexographic printing element, includes at least one laseroptical substrate, and one elastomeric reliefoobrazuyushchey layer with a thickness of at least 0.2 mm, containing at least one elastomeric binder, and the method includes at least the following stages:
(a) application suitable for laser engraving of flexographic printing element on a cylindrical support and the mounting of the cylindrical bearing in the mounting block
(b) providing a cylindrical bearing during the rotation,
(c) engraving of the printing relief in the relief-forming layer by using at least one laser beam, and the depth to be laser engraved embossed elements is at least 0.03 mm,
and catch using the suction device is formed during the etching gas or consisting of separate particles of the products of decomposition and clean saturated with the products of decomposition of the flow of exhaust gas through the system from at least two different filter settings, and the first filter unit consisting of separate individual particles of the decomposition products in the presence of finely dispersed, non-sticky solids using a filter with the particulate filter material and then on the second filter unit oxidation is removed from the stream is thedamage gas remaining therein gaseous products of decomposition.
Below the present invention is more explained in the description of examples of implementation with reference to the accompanying drawings on which is shown:
Figure 1: schematic diagram of the process comprising a pump (4), filter (5) with a solid filter material and the stage (6) oxidative treatment
Figure 2: schematic diagram of the filter (5) with a solid filter material
Figure 3: schematic diagram of the stage (6) oxidative treatment
Figure 4: schematic diagram of the preferred options for performing suction
Figure 5: preferred embodiment of the suction in the cut
6: another preferred embodiment of the suction in the section.
Below the present invention is discussed in detail:
As source material for implementing the method according to the invention is applied suitable for laser engraving of flexographic printing element, which is fundamentally known form contains at least one laseroptical substrate and elastomeric reliefoobrazuyushchey layer thickness of at least 0.2 mm, preferably at least 0.3 mm and particularly preferably at least 0.5 mm As a rule, the thickness is from 0.5 to 2.5 mm
In a fundamentally known as ramarotafika the substrate is a polymer film or metal f is LGW, or also cylindrical sleeve. Reliefoobrazuyushchey layer contains at least one elastomeric binder. Examples of suitable elastomeric binders include natural rubber, polybutadiene, polyisoprene, styrene-butadiene rubber, nitrile-butadiene rubber, butyl rubber, styrene-isoprene rubber, polynorbornene rubber or ethylene-propylene-diene rubber (ccept) or termoplasticheskie elastomeric block polymers, styrene-butadiene or styrene-isoprene type. Reliefoobrazuyushchey layer is usually obtained by crosslinking capable of crosslinked layer, which contains at least these binders and suitable for crosslinking component such as ethylene unsaturated monomers suitable initiators. The crosslinking can be carried out, for example, photochemically. Next can be used, if necessary, the laser radiation absorbers, plasticizers, and other excipients such as colorants, dispersants or the like. Suitable for laser engraving of flexographic printing elements are in principle known. Suitable for laser engraving of flexographic printing elements can have only one reliefoobrazuyushchey layer, or several similar or different structures. The details of the structure and composition suitable for the laser is engravable flexographic printing elements, described, for example, in the publications: WO 93/23252, WO 93/23253, US 5259311, WO 02/49842, WO 02/76739 or WO 02/83418, the contents of which are incorporated into this description by reference.
The method according to the invention is not limited to the use of well-defined flexographic printing elements as starting materials. However, the advantages of the proposed method is especially pronounced when using such flexographic printing elements, reliefoobrazuyushchey layer which includes components containing butadiene and/or isoprene units as structural elements. It should be mentioned, in particular, binders containing butadiene and/or isoprene units, such as, for example, natural rubber, polybutadiene, polyisoprene, styrene-butadiene rubber, nitrile-butadiene rubber, styrene-isoprene rubber or termoplasticheskie elastomeric block copolymers of styrene-butadiene or styrene-isoprene type, such as SBS or SIS block copolymers. Next should be called plasticizers containing butadiene or isoprene, such as, for example, oligomeric styrene-butadiene copolymers, liquid oligoovulation or oligothiophene, in particular those with a molecular mass ranging from 500 to 5000 g/mol, or liquid oligomeric Acrylonitrile-butadiene copolymers. In direct laser gruberova the AI such flexographic printing elements are formed of exhaust gas with high content of butadiene and/or isoprene, which, however, can be reliably and economically cleaned proposed in the invention method.
Laser apparatus used for implementing the method according to the invention is an apparatus with a so-called rotating cylinder. This instrument is in principle a known manner includes a unit for mounting a cylindrical support for flexographic printing elements, so that the cylindrical bearing can be installed with the possibility of its rotation. Installation unit is connected with a driving unit, whereby the cylinder may be driven in rotation. To ensure smooth, cylindrical bearing, as a rule, should be chocked on both sides. This kind of equipment is in principle known. Its design and its principle of operation are described, for example, in EP-A 1262315 and EP-A 1262316 or WO 97/19783. Details are disclosed in particular in EP-A 1262315 on p.14-17.
In the case of a cylindrical support it could be, for example, about the support shaft made of metal or other material, on which by means of double-sided adhesive tape is pasted conventional planar flexographic printing element on a flexible substrate. As flexographic printing elements can also be used so-called sleeves (sleeves). In the case of sleeves reliefoobrazuyushchey layer applied directly or indirectly on the cylindrical support, the example aluminium or plastics. The sleeve itself is embedded in the printing machine. In the normal case bearing completely wrapped in reliefoobrazuyushchey layer. Then talk about the so-called endless and seamless sleeves. To improve printing properties can also be provided by a flexible basis between the relief-forming layer, if necessary, with laseroptical substrate or without her sleeve.
Sleeves can be mounted directly in the setup block. A cylindrical bearing sleeve in this case is identical with the cylindrical support equipment. Sleeves can also be worn on a support platen and fixed. Generally, as the sleeves you can use the so-called air cylinders, thus putting the sleeve on the support cylinder and its removal is performed using an air cushion of compressed air. Details of this are reported, for example, in: "Technik des Flexodrucks", S.73 ff., Coating Verlag, St. Gallen, 1999.
The apparatus will further constrain the laser head, which emits at least one laser beam. Preferably used heads that emit multiple laser beams, for example, three laser beam. They may have different power. Laser head and a cylindrical bearing mounted coaxially with the possibility of displacement relative to each other. During operation of the apparatus the cylinder is practical bearing is driven into rotation, and the laser beam and the cylinder is progressively shifted relative to each other, so that the laser beam is gradually feels the entire surface of the flexographic printing element and change accordingly, depending on the control signal, the intensity, removes from the surface more or less material. For the present invention it does not matter how translational movement between the laser head and the cylinder. For this purpose, or the cylinder can be installed with the possibility of offset or laser head, or both.
The apparatus used for implementing the present invention will further constrain the device for sucking formed during etching of decomposition products. The suction should be placed as close as possible to the place in which the laser beam falls on the surface of the relief-forming layer. It can be located above the bell. Suction may be recorded in the equipment or in the case movably installed laser head preferably can be moved together with the laser head. Specialist in principle known design of suction for laser heads. For example, you can specify WO 99/38643 ER-AND 330565.
All equipment is preferably closed in the casing, to the extent possible, to prevent unwanted output product of the Tobit decomposition in the environment. Access to the inside of the apparatus, in particular to the laser head and the support cylinder is provided through lockable doors, door, sliding doors and the like.
The method according to the invention and preferred options for its implementation is schematically presented in Fig.1-6. In this figure serve only for the purpose of better understanding the invention and should not be construed as limiting the invention provides examples of its implementation.
Figure 1 schematically shows the process as a whole. Shows the cylinder (1)on which is mounted flexographic printing element. The laser (2) emits a laser beam (3), which etches reliefoobrazuyushchey layer. For greater clarity, shows only one laser and only one ray, but we can talk about a few rays of several homogeneous or heterogeneous lasers such as CO2lasers or Nd-YAG lasers. Through the pump (4) is the suction layer decomposition products formed during laser operation, the mixture of air, aerosol and gaseous products (7) decomposition of the pipeline is fed to a filter unit. For greater clarity, in figure 1 is not shown suction units, such as fans, vacuum pumps or the like, which are required for the extraction and movement of the exhaust gas. Depending on the pressure loss of the entire us what device can be quite a single suction unit or may require installation of several suction units in various locations.
The volume of gas sucked in a unit of time (volumetric flow rate of exhaust air) and per unit mass of the captured material, chosen specialist considering the nature of the applied flexographic printing element, the design of the laser head, process engraving, and in accordance with the required surface cleanliness engrave printing plates. In the normal case, the surface of the printing form is contaminated with decomposition products the less, the higher the volumetric flow rate of exhaust air. Needless to say, a specialist can work with a smaller volumetric flow rate of exhaust air, if, in his opinion, for any application sufficient lesser degree of surface cleanliness. However, as a rule, it is recommended to work with a volumetric flow rate of exhaust air, at least 0.1 m3/g of the captured material. Preferably the volume flow of the exhaust air is at least 0.5 m3/g and particularly preferably at least 1.0 m3/year For laser equipment of medium size, calculated on the engraving plate measures approximately 1 m2and removal of material in the range from 500 to 1000 g/m2this corresponds, depending on the removal of the volumetric flow rate of at least 50 to 100 m3/h, preferably at least 250 to 500 m3/h and especially before occhialino at least 500 to 1000 m 3/PM
Stream (7) of the exhaust gas is first cleaned the filter with particulate filter material, respectively on the filter (5) with solid granular material. Thus separated is contained in the gas stream particle decomposition products, such as adhesive aerosols, while the gaseous components of the exhaust gas pass through the filter. The filter with particulate filter material contains principally known suitable filter elements for separating solid particles. Particle decomposition products produced in the presence of finely dispersed, non-sticky solids. This prevents bonding of the filter element adhesive aerosols. Fine particulate matter can be dosed directly into the filter with particulate filter material. However, it is preferable to apply it from the supply tank (8) in the pipeline (7) before the filter, for example, using a suitable carrier gas, to achieve the most subtle mixing with the exhaust gas. Fine non-adhesive solid covers adhesive aerosols and filter elements. Thus it prevents the bonding of the solid filter material of the filter. Instead, the result is well separated solid substance (9). As Tonkolili the red sticky solid substances may be considered, in particular, solids with at least 20%of particles not larger than 20 μm. Preferably, the proportion of particles not larger than 2 μm is at least 50%.
Examples of suitable solids include clay, caso3, activated carbon, SiO2organically modified silicic acid, zeolites, fine powders of kaolinite, Muscovite or montmorillonite. The amount of solids is determined by a specialist depending on the type of exhaust gas. As a General rule is quite sufficient amounts of solids of from 0.1 to 10 g per gram of the captured material, preferably from 0.5 to 2 g per gram of the captured material.
Filter design with solid filter material is of no importance for the present invention. A typical embodiment of the filter with particulate filter material is presented in figure 2. Saturated solids gas (7) is mixed with finely dispersed solids (8) and in the filter with one or preferably multiple filter elements (12) is subjected to filtering with the mission of the Department of solid substances. The result is a gas stream (10), essentially free of solids and containing only gas, respectively, of volatile decomposition products. In the normal case can be achieved article the stump clean above 99% relative to the initial number of particles of decomposition products. Certain amount of gaseous decomposition products under certain circumstances can be absorbed on fine particulate matter (8) and separated on the filter with particulate filter material. When selecting the filter elements can be used, in principle, well-known specialist of the filter elements such as filter candles made of ceramic materials. Filters with particulate filter material commercially available.
Stream (10) of the exhaust gas, still saturated with gaseous decomposition products, is fed to the second filter unit (6), which is the oxidative destruction of the remaining decomposition products. The result is an exhaust gas (11), which are essentially free from organic substances. As oxidizers can be considered primarily atmospheric oxygen and derived reactive oxygen species, such as atomic oxygen or ozone.
In the case of the second filter installation we can talk about, for example, thermal oxidation. This kind of setup can work, in particular, oil or natural gas. Preferably the exhaust gas is introduced directly into the flame. Typical combustion temperatures are about 800°C. Installation of thermal afterburning can serve to exclude the sustained fashion laser engraving. However, as such a thermal afterburning can also be used setting in which you are burning other waste gases or waste. In this case, the exhaust gas with laser engraving just served on an existing installation.
In a preferred embodiment of the invention at the stage oxidation treatment used device for catalytic oxidation of exhaust gases. This is contained in the exhaust gas of the gaseous decomposition products undergo oxidation in the presence of a suitable catalyst, mainly to CO2and H2O. as catalysts can be considered, for example, catalysts based on noble metals on suitable carriers or catalysts based on transition metal oxides, or other compounds of transition metals such as V, Cr, Mo, W, Co or Cu. The specialist will make a corresponding selection of the possible catalysts depending on specific conditions. When selecting the catalyst must also be considered subject to the engraving material. Typically, the catalysts based on noble metal have a higher activity than catalysts based on transition metals, but more sensitive to catalyst poisons, such as H2S or other serondela is their connection. So for engraving flexographic printing elements, which contain sulfur-containing compounds such as sulfur-containing crosslinking agents, it is recommended to use catalysts based on transition metal oxides. Stage catalytic purification is usually carried out at temperatures in the range from 250 to 400°C. More detailed information about the catalytic oxidation and applied catalysts, see: Martin Goede, "Entstehung und Minderung der Schadstoffemissionen bei der Laserstrahlbearbeitung von Polymerwerkstoffen", Fortschritt-Berichte VDI, Reihe 5, Nr.587, Düsseldorf, VDI-Verlag, 2000, Seiten 36 bis 41 and cited in the literature, the contents of which are incorporated into this description by reference.
In another preferred embodiment of the invention at a stage of oxidation purification device used for oxidation of exhaust gases using low-temperature plasma. Low-temperature plasma is generated not by thermal activation, and strong electric fields (electric discharge lamps). Thus ionize only a small number of atoms or molecules. In low-temperature plasma, used according to the present invention, contained in the exhaust gas of oxygen are formed, in particular, oxygen radicals or radicals containing oxygen atoms, for example BUT•that then, its about ered, react with gaseous decomposition products relief-forming layer and the oxidation destroy them. Methods of creating low-temperature plasma specialist known. As an example, should indicate to US 5698164. Suitable reactors are commercially available. For example, you can use the ozone generator to generate ozone and then enter it into the off-gas flow. Exhaust ozonoterapie gas can then pass through the device where it is exposed to UV radiation, mainly mainly short-wave UV radiation. UV light creates additional with oxidizing effect radicals, and thereby accelerates the decomposition of volatile organic compounds. Low-temperature plazmogeneratora known.
In a preferred embodiment of the method according to the invention the filter unit (6) includes one buffer installation included before stage (15) oxidative treatment. This buffer setup is shown schematically in figure 3. The buffer setting (13, 14) is a full or partial collection contained in the exhaust gas of the gaseous components, which are then gradually again heading in a certain concentration on stage oxidative treatment. The advantage of this variant is that it allows you to smooth p is the same concentrations of gaseous decomposition products in the exhaust gas, so the filter unit does not necessarily have to be designed for maximum power, but can work in more or less continuous mode, for example, exactly when because of the change of the printing form engraving is not performed.
The buffer unit may be, for example, two vessels (13, 14), filled with a suitable for absorption by the material. Under suitable absorption material refers to zeolites, in particular hydrophobic zeolites with pore size from 5 to 6 angstroms. Work buffer settings can be made so that the first decomposition products are collected in a single absorber, until it reaches its maximum saturation. Then switches to another absorber, and in the ground at this time is desorption, for example, by increasing the temperature and/or transmission of gases, with a gradual issuance of absorbed organic substances on stage (15) oxidative treatment. Needless to say that other options are also possible execution buffer installation. For example, in the normal case, you would have to direct exhaust gases directly to the stage oxidation treatment and only when exceeding a certain number of portable gas organic impurities part of the flow to avoid overloading the stage oxidative PTS is tough to get out through the buffer. Then at lower load the contents of the buffer can again return to the stream of exhaust gas.
Needless to say, the method according to the invention may include other stages, and used equipment of all other components. For example, there may be provided an additional filter unit, in which purposefully separated impurities H2S or other sulfur containing compounds. It can be, for example, absorption stage filtration (e.g., alkaline leaching) or biofilters.
To describe the combination of two filter units can be connected to only one installation for direct laser engraving. However, if the production will take several laser devices, these several laser devices can also be connected to one of the existing combination of filter installations for co-purification of exhaust gases from all laser devices.
In a particularly preferred embodiment of the method according to the invention uses a special suction device, schematically shown in Fig.4-6. Thanks to this device is especially full and fast sucking decomposition products and almost completely eliminated the contamination of the surface of the engraving of flexo printing forms product is Tami decomposition.
The suction device (4) connected to the laser head (laser head figure 4 for clarity, not shown). If the suction device is mounted movably, it moves together with the laser head. The suction device is a hollow body with a rear side (16)and located against the rear side of the suction hole (17) and, with the exception of through holes, which will be described below, is closed. The corresponding opposite surfaces may be parallel to each other, but this is optional. The surface may also have a curvature or two surfaces may jump one another without edges. In addition to the holes necessary for the operation of the device is essential for the invention is the type and location of suction holes (17).
The suction device (4) has at least one pin (18) for connection to the suction line (19). Conclusion (18) is preferably on the rear side (16) or on the lower side of the suction device, which, however, may not be considered as limiting the invention in such a location output. May be there are several conclusions to the exhaust gas, Then on the back side there is a box (20) for passing the laser beam (3). Needless to say that if he is Auda multiple laser beams, the suction device can also have more than one window. Figure 4 shows three of a laser beam. Preferably, in any position, near the Windows, for example above or below Windows, was located one or more nozzles (17), through which on Windows is skipped compressed air or other gas for purging. Thanks preventing contamination or even a full driving laser Windows decomposition products relief-forming layer. Reasons of clarity, the nozzle not shown.
The suction hole (17) has two opposite, in the normal case horizontal arcuate edges (21) and (21A), the radius of which is made in accordance with the radius of the reference cylinder. The length of the edges (21) and (21A) are the same. Figure 5 shows a cross section through the supporting cylinder (1) and the suction device (4). On the supporting cylinder (1) is suitable for laser engraving of flexographic printing element (23). The support cylinder is accurately size formed in the arcuate edges of the sector. The distance between the edges (18) and (21A) and the surface of the flexographic printing element in the drawing, denoted by the Greek letter Δ. Typically, distance Δ must be less than 20 mm (Δ<20 mm). Preferably Δ is from 1 to 8 mm, and particularly preferably from 2 to 5 mm, the Distance between the surface of the base cylinder and the edges (21) and (21A), of course, more distance Δ between the surface of the flexographic printing element and edges.
The arcuate edge is preferably in the form of a circular edges. In this case, the distance Δ along all edges equally. However, it may be provided with an elliptical or otherwise shaped edge. In this case, the distance Δ along the edge of change. It is preferable, however, that in this case Δ at each point of the edge was less than 20 mm Variable length Δ it may happen even when the support cylinder is replaced by another reference cylinder with a smaller radius. But this should be avoided whenever possible, and for supporting cylinders of different diameters, it is recommended to have in stock hoods suitable for each specific case.
The ends of the arcuate edges form an angle of α. This angle is determined by the size of the suction openings. The angle α can be up to 180°. Paid off the corners α within from 30° to 180°. The ends of the edges (21) and (21A) are connected opposite to each other by edges (22) and (22A). These edges are preferably at a distance of Δ surface suitable for laser engraving of flexographic printing element. Connecting edges can be made straight (as shown in figure 4) or the edges may have a curvature. Preferred are straight-edge.
Figure 6 shows another embodiment of the suction device. In this case, the edge (21) (21A respectively), not shown) has an extension in the form of a linear edge (24). In this zone, distance Δ it is not observed. Angle α applies only to the actual arcuate edge (21) and (21A), as shown in Fig.6.
All edges should be preferably rounded in order to avoid unnecessary turbulence. Additionally around the edges (21), (21A), (22) and/or (22A) may provide for the construction, which serves to increase the cross-section of the air intake during a suction exhaust air. Suitable structures are, for example, a flat or curved steel sheets located a console or the like of the flanges around the actual suction head.
If necessary, the suction device may have other openings, such as holes for entering analytical instruments, transmitters, or the like, respectively of the connecting elements to them.
It is advisable to connect, for example, by means of the clamp screws of the suction device with the laser head so that it can be easily removed. Because of this when replacing the cylindrical support to another, with a different radius possible without a greater Oteri time to mount a new suction device with the corresponding appropriate radius.
To implement the method according to the invention, a first cylindrical bearing is applied suitable for laser engraving of flexographic printing element and a cylindrical bearing mounted in the mounting block. For mounting the laser head and the cylindrical bearing plant from each other enough to ensure a smooth installation. The sequence of operations is not important. If we are talking about planar flexographic printing element, the first can be embedded in the hardware of the cylindrical support, and then print the form. The alternative provides that the cylinder and flexographic printing element can be pre-assembled outside the apparatus and is then embedded in the equipment. When engraving consistently several different flexographic printing elements supporting the cylinder can, of course, leave the mounting device and mounting flexographic printing element to produce on the already built-in installation of the device the cylinder. The same is true for the case when using the sleeve in combination with a support cylinder, for example with an air cylinder. If the sleeve is self-supporting, that is, without additional cylinder, the relief layer, of course, is already installed on the cylindrical support. After mounting cilindric the Skye bearing, equipped with flexographic printing element is driven into rotation by the drive unit.
Then, using at least one laser beam engraving is printed relief on the relief-forming layer. The depth of the subject of the engraving elements is determined by the total thickness of the terrain and the type subject to the engraving elements and is determined by a specialist, depending on the specified properties of the printing form. The depth to be engraving the relief elements is at least 0.03 mm, preferably at least 0.05 mm - here are the minimum depth between the individual pixels. Printed forms with too little depth of relief, as a rule, unsuitable for printing with flexographic equipment, because the negative elements are filled with printing ink. Usually some negative points have more depth; for points with a diameter of 0.2 mm recommended depth typically ranges from 0.07 to 0.08 mm At engrave surfaces it is recommended that the depth of more than 0.15 mm, preferably 0.3 mm, and particularly preferably more than 0.5 mm Last is, of course, is possible only at the relief of having an appropriate thickness.
The laser apparatus may have only one laser beam. However, preferably the apparatus has two or more of the laser beams. All the laser beams may have the same wavelength or can be used laser beams with different wavelengths. Further, it is preferable that at least one of the beams has been adapted to create a rough structures and at least one of the beams is to write the finest structures. Such structures can be formed precisely and beautifully high-quality printing plates. For example, lasers can be used CO2lasers, and beam to create the finest structures has less power in comparison with rays to create a rough structures. So, for example, is particularly successful was the combination of beams with nominal capacities ranging from 150 to 250 watts. Rays to create the finest structures are preferably used for etching only the edges of the embossed elements, and the upper section selfobsessed layer. Rays of greater capacity are preferable to deepen created structures, as well as for the extraction of larger napechatala recesses. Needless to say, the details are determined by the motive to be generated by the engraving.
After etching the actuator cylinder off again, and finished flexographic printing plates, respectively, of the finished sleeve removed.
As a rule, no cleaning of the printing form with the help dissolve the lei is not required. If necessary, residual dust or the like can be removed by simply blowing with compressed air or swept away with a brush.
If you still need additional cleaning, it is recommended not use solvent or mixture of solvents, contributing to a strong swelling of the printing form, but with a solvent mixture of solvents, less active in terms of swelling of the printing form. As the binders used are soluble in organic solvents, respectively, contributing to the swelling of the printing form binders, such as, for example, styrene-butadiene or styrene-isoprene block copolymers, it is advisable to conduct additional water or aqueous detergent solution. Water cleaners are composed primarily of water, and add if necessary, small amounts of alcohols and/or auxiliaries, such as, for example, surfactants, emulsifiers, dispersing agents or bases. Additional cleaning is carried out, usually by simple dipping or spraying relief printing plates, also supplemented by mechanical means, such as, for example, clearing brush or plush. Can also be used conventional flexographic wymiany tools.
Proposed in the invention is a method of obtaining flexographic the x print forms allows you to efficiently and economically clean the exhaust gas. In such cases, the maximum allowable content of impurities in the exhaust gas. It does not require costly reactivation saturated with decomposition products, absorbents, such as activated carbon, or to solve the issues of getting rid of them. The method allows to effectively separate and adhesive aerosols by coating non-adhesive solid without driving the filter. The unit can be made compact and small sizes. Therefore it is especially suitable for small and medium enterprises.
1. A method of manufacturing a flexographic printing forms direct laser engraving, by etching terrain suitable for laser engraving of flexographic printing element with the use of laser equipment that includes at least:
the unit cylindrical support for flexographic printing elements in which a cylindrical bearing can be installed with the possibility of its rotation,
drive unit for rotation of the cylinder,
the laser head emitting at least one laser beam, and the laser head, as well as installation the unit is installed coaxially with the cylindrical support with the possibility of displacement relative to each other, and
the suction device
in which way the quality is TBE source of the material used is suitable for laser engraving of flexographic printing element, includes at least one laseroptical substrate, and one elastomeric reliefoobrazuyushchey layer with a thickness of at least 0.2 mm, containing at least one elastomeric binder,
moreover, the method includes at least the following stages:
(a) application suitable for laser engraving of flexographic printing element on a cylindrical support and the mounting of the cylindrical bearing in the mounting block
(b) providing a cylindrical bearing during the rotation,
(c) engraving of the printing relief in the relief-forming layer by using at least one laser beam, and the depth to be laser engraved embossed elements is at least 0.03 mm,
characterized in that the catch using the suction device is formed during the etching gas or consisting of separate particles of the products of decomposition and clean saturated with the products of decomposition of the flow of exhaust gas through the system from at least two different filter settings, and the first filter unit consisting of separate individual particles of the decomposition products in the presence of finely dispersed, non-sticky solids using a filter with the particulate filter material and then on the second filter is Noah installing the oxidation is removed from the flow of exhaust gas remaining in him gaseous decomposition products by catalytic oxidation, moreover, the quantity of sucked gas is at least 0.1 m3per gram of the captured material and the second filter unit includes installed before the oxidation stage of purification buffer, which fully or partially collected contained in the exhaust gas of the gaseous decomposition products and from which they, in a certain concentration are issued for the oxidative purification step.
2. The method according to claim 1, characterized in that the oxidative decomposition of the second filter unit is produced using low-temperature plasma.
3. The method according to claim 1, characterized in that the finely dispersed non-adhesive solid substance is at least one substance selected from the group consisting of clay, caso3, activated charcoal or SiO2.
4. The method according to claim 1, characterized in that the suction device is a hollow body which is connected to the laser head and which has at least one rear side (16) with at least one window (20) to pass one or more laser beams, one arbitrarily set the output (18) for connection to the suction line (19), and the opposite rear side of the suction hole (17)and the suction hole has two opposite each other Dugoba the major edges (21) and (21A), the radius of which is made in accordance with the radius of the reference cylinder.
5. The method according to claim 4, characterized in that the distance Δ between the edges, as well as surface finds on the cylinder flexographic printing element is from 1 to 20 mm.
6. The method according to one of claims 1 to 5, characterized in that used as the source material suitable for laser engraving of flexographic printing element includes components that contain butadiene and/or isoprene as structural elements.
7. The method according to one of claims 1 to 5, wherein the flexographic printing element comprises a binder based on styrene-butadiene or styrene-isoprene block copolymers.
8. The method according to one of claims 1 to 5, wherein the flexographic printing element comprises plasticizers containing butadiene and/or isoprene.
SUBSTANCE: invention pertains to a printing matrix engraved by a laser, used for obtaining a relief image using known methods. Description is given of the printing matrix engraved by a laser, obtained through photocuring a compound on a photosensitive resin base (a), consisting of a polymerised unsaturated group and which has an average molecular mass between 1000 to 20 x 104, an organic compound (b), with a polymerised unsaturated group and average molecular mass less than 1000 and an organic silicon compound (c), with at least, one Si-O bond and not containing a polymerised unsaturated group. Content of the organic silicon compound (c), lies in the range from 0.1 to 10 % of the mass of the compound on the photosensitive resin base. Description is given of obtaining the printing matrix engraved by a laser, through formation of the given compound on a canvas or cylinder with subsequent linking and solidification under exposure to light.
EFFECT: increased resistance of the printing matrix to abrasion and to adhesion on its surface.
19 cl, 2 tbl, 12 ex
FIELD: manufacture of plates used for intaglio printing.
SUBSTANCE: method for making engraved plate with use of tool such as laser beam comprises steps of using engraving tool operating with use of data of depth card formed on base of three-dimensional raster image of printed document; similarly making intermediate engraved plates.
EFFECT: shortened time period for engraving high-quality plates, prevention of warping of plates at printing process.
21 cl, 15 dwg
FIELD: processes and equipment for making printing forms for screen printing, apparatuses for screen printing.
SUBSTANCE: method for making printing forms comprises steps of melting heat sensitive material of printing forms for screen printing having film of thermosetting resin of predetermined thickness by heating thermal head for perforating holes permeable for printing ink; forming large number of shallow recesses in one side of said film. Heaters of thermal head 10 have such size that next inequalities HM > 0.6PM, HS > 0.7 PS are satisfied. Heaters are arranged at pitch PM in side of main scanning direction. Length of heaters along side of main scanning direction is equal to HM. Feed stroke at side along secondary direction of scanning is equal to PS. Length of heaters at side along secondary direction of scanning is equal to HS. Side of film opposite to its side having shallow recesses is heated due to heating thermal head 10 with output 35 mJ/mm2 or less for melting heated zone until its communication with said recesses in order to form holes permeable for printing ink.
EFFECT: possibility for thermally perforating in film individual holes permeable for typographic ink at the same output of thermal head, realization of screen printing process at using material of printing forms for screen printing containing only film of thermoplastic resin.
18 cl, 9 dwg
FIELD: multicolor printing methods.
SUBSTANCE: method involves transferring positive image formed on film onto carbon-treated microporous rubber; dividing portion of microporous rubber of, for example, round shape, which had not been subjected to pulsed light treatment, into n number of sectors of different shapes; creating boundaries between sectors by exposing microporous rubber to thermal action of maximal depth. With 1.5 mm thick rubber, depth of boundary shall be at least 1.1 mm and shall not exceed 1.4 mm, said depth preferably approximating to thickness of rubber. Upon subjecting rubber to thermal action, pores are caked to define boundary, which protects sectors from mixing of inks of different colors. Resultant sectors are further charged with inks of different colors.
EFFECT: provision for creating of high-quality multicolor print.
FIELD: mechanics; air conditioning systems.
SUBSTANCE: invention relates to the method and the device for air conditioning indoors by means of an air mixture with a reduced oxygen partial pressure compared to that of ambient air. The invention aims for developing a method of air conditioning indoors including a necessary air regeneration, particularly in premises intended for people, which would allow creating the conditions of norm barometric hypoxia in the most cost effective way. The problem of air conditioning in a single premise (38) is solved by using an air mix with a reduced partial pressure compared to that of ambient air. Here, note, one part of oxygen (O2) contained in ambient air is reduced to a reaction product in exchange reaction with a combustible substance. The air mix thus processed is fed as a plenum air into the above single premise (38) to be air conditioned. The method is implemented by using device (10) intended for air conditioning in single premise (38) by means of an air mix with a reduced partial pressure compared to that of ambient air including O2, a reducing agent (16) to reduce one part of (O2), contained in ambient air in exchange reaction with a combustible substance to form a reaction product. There is also a feeding device (37) to force thus processed air mix into single premise (38) to be conditioned.
EFFECT: availability of the device for air conditioning the premises to work in the conditions of reduced partial pressure of oxygen.
25 cl, 4 dwg
FIELD: gas purification.
SUBSTANCE: method comprises purifying gas in vortex chambers provided with a rotating gas-liquid layer and causing the gas to be in a contact with the liquid main absorber. The time interval for which gas stays within the layer ranges from 0.001 to 0.1. The absorber additionally has soluble catalyzer for oxidizing hydrosulfides by oxygen. The trapped hydrogen sulfide is oxidized in the vortex chamber producing soluble oxygen-containing composition of sulfur.
EFFECT: improved method.
3 cl, 1 tbl, 8 ex
FIELD: purification of gases.
SUBSTANCE: device comprises housing (1) with inlet branch pipe (2) and outlet branch pipe (3). Housing (1) receives the catalytic stack made of two parallel perforated plates (4) made of a stainless steel and coated with small-mesh grid (5). Loose catalyzer is interposed between plates (4). The axis of inlet branch pipe (2) is parallel to the plane of the perforated plates. Inlet branch pipe (2) underlies the catalytic stack, and outlet branch pipe is mounted above the catalytic stack on the opposite side.
EFFECT: enhanced efficiency of purification.
2 cl, 3 dwg
FIELD: environmental protection.
SUBSTANCE: method comprises adding at least one nitrogen-containing reducer to the industrial exhaust gas containing NOx and N2O in amount sufficient for at least complete reduction of NOx. The mixture produced is supplemented with hydrocarbon, monoxide of carbon, hydrogen or a mixture of these gases for reducing N2O and is forced to flow through at least one reaction zone at a temperature up to 450°C.
EFFECT: enhanced efficiency.
6 cl, 4 ex
FIELD: chemical industry; other industries; methods and the devices for reduction of the nitrogen oxides content in the technological and effluent gases.
SUBSTANCE: the invention is pertaining to the method of reduction of the nitrogen oxides content in the gases, in particular, to the technological and effluent gases and also to the device used for realization of this purpose. The method provides for gating of N2O - and NOх-containing gas through the row of two catalyst layers containing one type or some types of zeolites loaded with iron, addition of the reducing agent foe NOx between these layers of the catalyst, maintenance of the temperature less, than 500°С in first layer of the catalyst and in the second layer of the catalyst, maintenance of the gas pressure, at least of 2 bar in both layers of the catalysts, selection of a such volumetric speed flow in the first and second catalyst layers, that in first layer of the catalyst the decomposition of N2O till its content of no more then 90 % with the respect to the contents of N2O at the inlet of the first layer of the catalyst and set the content of N2O more, than 200 parts per million, and that in the second layer of the catalyst the further decomposing of N2O contained in the gas, at least, by 30 % with the respect to the contents of N2O at the inlet of the second catalyst layer. The device used for reduction of the contents of NOX and N2O in the gases, in particular, in the technological gases and the effluent gases includes: two catalyst layers disposed one after another and containing one type or some types of the iron loaded zeolites, through which the gas containing NOX and N2O passes. At that the device is disposed between catalyst layers for injection of the gaseous reducing agent in the stream containing NOX and N2O of the gas includes the mixer, through which the gas is gated after passing the first layer of the catalyst and including the pipe duct for the reducing agent, which enters in the space after the first layer of the catalyst in front of the mixer or in the mixer. The subjected to purification gas after passing through the mixer is gated through the second layer of the catalyst. At that at least, one of the layers of the catalyst is made in the form of the hollow cylinder, through which the gas containing NOX and N2O passes radially. The technical result of the invention consists in development of the simple and cheap method, which ensures the good degree of conversion both at decomposition of NOX, and at decomposition of N2O, which are differing by the minimum operation and investment expenditures.
EFFECT: the invention presents the simple and cheap method, which ensures the good degree of conversion both at decomposition of NOX, and at decomposition of N2O, which are differing by the minimum operation and investment expenditures.
21 cl, 1 tbl, 6 dwg
FIELD: chemical industry; heat-and-power industry; oil-processing industry; propulsion engineering: production of the industrial and household air purification installation.
SUBSTANCE: the invention is pertaining to the environmentally appropriate oxidation of the gaseous compounds and may be used in the heat-and-power engineering, oil-processing industry and chemical industry, in propulsion engineering and also in production of the industrial and household air purification installations. The device of the catalytic oxidation of the gaseous compounds consists of the body (1) with the inlet fitting pipe (2) and the outlet fitting pipe (3). Inside the body there is the block carrier (4), which has been made out of the open-cellular metallic foam coated with the courses of the secondary carrier and the catalytically active agent. The device additionally has the heat pipes (5), the evaporation sections (6) of which are arranged in the block carrier (4) and fastened to it, and the condenser-type sections (7) are arranged out-of-the body. The gaseous compounds are fed through the fitting pipe (2) into the body (1) and are filling in the block carrier (4). As the block carrier (4) achieves the stationary operational temperature the reaction of the catalytic oxidation of the gaseous compounds runs in the device. The products of the reaction leave the device through the fitting pipe (3). At the unexpected rise of the block carrier (4) temperature its cooling takes place as the result of the heat transfer of the evaporation section (6)of the heat pipes (5). Further the steam enters the condenser-type section (7). The hidden heat of the steam condensation is transferred in the environment. The invention allows to improve reliability of the device operation due to addition of the thermal stabilization system.
EFFECT: the invention ensures the improved reliability of the device operation due to addition of the thermal stabilization system.
FIELD: inorganic synthesis catalysts.
SUBSTANCE: decomposition if N2O under Ostwald process conditions at 750-1000°C and pressure 0.9-15 bar is conducted on catalyst, which comprises (A) support composed of α-Al2O3, ZrO2, SeO2, or mixture thereof and (B) supported coating composed of rhodium or rhodium oxide, or mixed Pd-Rh catalyst. Apparatus wherein N2O is decomposed under Ostwald process conditions on the above-defined catalyst is also described. Catalyst is disposed successively downstream of catalyst grids in direction of stream of NH3 to be oxidized.
EFFECT: increased catalyst activity.
8 cl, 2 tbl, 3 ex
FIELD: environmental protection; devices and the methods of control over NOx contents in the flue gases ejected from the boilers burning the carbonic fuels.
SUBSTANCE: the invention is pertaining to the device and the method of control over NOx contents in the flue gases ejected from the boilers burning the carbonic fuels. The method includes injection of the carbonic fuel and the air into the burning zone of the furnace of the boiler for incineration of the carbonic fuel in the conditions of oxidization and production of the flue gas includingNOx and CO, and directing the flue gas from the furnace into the section of the catalyst in the channel of the flue gas for restoration of NOx and CO and conversion of the NOx and CO without injection of the external reactant intoN2 and CO2 by usage of CO in the capacity ofthe deoxidizer for NOx on the catalyst in the catalytic section. The technical result of the invention is development of the device and the method for control over the NOx ejections from the boilers burning the carbonic fuels, which are maintaining the high thermal efficiency of the boilers without the increase of ejections of other pollutions and which do not use any external reactant.
EFFECT: the invention ensures development of the device and the method for control over the nitrogen dioxide ejections from the boilers burning the carbonic fuels, which are maintaining the high thermal efficiency of the boilers without the increase of the ejections of other pollutions and which do not use any external reactant.
18 cl, 2 dwg
FIELD: environmental protection; reactors for catalytic purification of the industrial gaseous outbursts.
SUBSTANCE: the invention is pertaining to the field of environmental protection against the industrial gases release and may be used for the flameless purification of the gaseous emissions of the industrial enterprises. The reactor for catalytic purification of the industrial gaseous outbursts contains the cylindrical body, which internal surface is coated with the catalyst, the source of the infra-red source located in the body, the tubular heat exchanger, the permeable cylindrical shell ring from the catalyst, installed in the upper part of the body so, that the symmetry axes of the shell ring and the body coincide. The tubes of the heat exchanger are mounted inclined and arranged along the round perimeter of the reactor. At that the source of the infra-red emission made in the form of the cylindrical section is built in the body, where the movable bottom door is installed. The annular partition of the heat exchanger with the located on it collector of aromatization is installed before the outlet of the purified gaseous stream. The movable bottom door used for regulation of the purification degree of the gaseous outbursts is installed in the upper part of the body of the reactor. The invention allows to decrease the power input, to recover the heat and to aromatize the leaving purified gaseous stream.
EFFECT: the invention ensures the decreased power input, the recuperation of the heat, the aromatization of the leaving purified gaseous stream.
2 cl, 3 dwg
FIELD: catalyst for improved hydrolysis of carbon oxysulfide (COS) and hydrocyanic acid (HCN) in gaseous mixtures.
SUBSTANCE: invention relates to application of TiO2-based composition as catalyst for COS and/or HCN in gaseous mixture releasing from apparatus for joint energy production, wherein said composition contains H2, CO, H2S and H2O in amounts of 10-40 %; 15-70 %; 200 ppm-3 % and 0.5-25 %, respectively. Moreover abovementioned composition contains at leas 1 mass.%, preferably at least 5 % at least one alkali-earth metal sulfate selected form calcium, barium. Strontium, and magnesium.
EFFECT: high conversion ratio of COS and HCN, irresponsiveness to presence of NH3, decreased production of CO2 and CH4.
8 cl, 5 ex
FIELD: mechanical engineering; ventilation systems.
SUBSTANCE: invention can be used for cleaning process and ventilation gases from gaseous admixtures at one-time steam-gas discharges. Proposed bubbling and foaming device has housing 1 installed on tank 2 with solution which form foams crubber, together with jet former 3 and pump 4, aerator 5, cylindrical perforated skirt 6, solution take-off branch pipe 7 and solution delivery branch pipe 8, and air suction branch pipe 9, gas mixture feed branch pipe 10, air branch pipe 11 and exhaust gas discharge branch pipe 12.
EFFECT: improved cleaning of gases.
4 cl, 1 dwg
FIELD: devices for cleaning waste gases from mineral dust and decontaminating the organic component of waste gases; electrode, mining, by-product coke, chemical, oil, oil refining industries and metallurgy.
SUBSTANCE: proposed device consists of decontamination and cleaning unit arranged in heat-insulated housing 1 dividing inner cavity of housing into contaminated gas chamber, working chamber and cleaned gas chamber; it is provided with burner 2 equipped with gas duct 4 for delivery of natural gas; it is communicated with contaminated gas chamber. Decontamination and cleaning unit consists of row of shelves with catalyst cassettes 11. Contaminated gas chamber is provided with branch pipe 5 for delivery of contaminated gas. Cleaned gas chamber is provided with gas duct 7 for discharge of cleaned gas. End faces of shelves are rigidly interconnected in turn by means of blind partitions 10, thus forming meander-type structure. Catalyst cassettes 11 are made from artificial mullite-containing fiber material. Shelves are made in form of lattice 9 and are directed in way of gas flow. Provision is also made for assembly of two devices rigidly interconnected by means of common wall of heat-insulated housing and communicated through transportation gas main.
EFFECT: enhanced ecological safety; facilitated procedure of scheduled maintenance; increased productivity; continuity of process.
20 cl, 2 dwg
FIELD: gas treatment techniques.
SUBSTANCE: invention relates to sorption engineering and can be used for separation gas mixtures containing methanol, in particular removing methanol from gas mixtures containing air, organic and inorganic gases. Method comprises sorption of methanol vapors from preliminarily dried gas mixture using, as adsorbent, porous matrix selected from following series: silica gel, alumina or vermiculite, and porous coals, whose pores contain halide or nitrate of metals selected from series: calcium, magnesium, lithium, nickel, and cobalt in amount not less than 10%.
EFFECT: increased amount of adsorbed methanol.
FIELD: environmental protection.
SUBSTANCE: method comprises treating unsymmetrical dimethylhydrazine and transformation products thereof with oxidant, particularly potassium permanganate in the form of 0.1 to 5.0 kg/m3 aqueous solution containing also promoting additive: nitric acid, hydrogen peroxide or sodium peroxide in amount 0.1-1.0 kg/m3.
EFFECT: accelerated detoxification process, ensured environmental safety, and reduced consumption of reagents.
2 cl, 4 tbl, 3 ex
FIELD: oxidation catalysts.
SUBSTANCE: invention relates to oxidation catalysts that can be, in particular, used for complete oxidation of volatile organic compounds into CO2 and H2O. Catalyst according to invention contains mixed copper, manganese, and lanthanum oxides, wherein metals can assume multiple oxidation states and whose chemical analysis expressed for metals in lowest oxidation states is the following: 35-40% CuO, 50-60% MnO, and 2-15% La2O3.
EFFECT: enhanced stable catalytic activity and resistance to caking.
11 cl, 2 tbl, 2 ex
FIELD: chemical industry; metallurgy industry; methods of purification of inert gases from methane.
SUBSTANCE: the invention is pertaining to the field of chemical industry and metallurgy industry, in particular to the method of purification of the inert gas from methane, mainly to the methods of recording of ionizing radiations in the nuclear physics, where produce or use the ultrapure inert gases. Purification of the inert gas from methane is performed with the help of the catalyst, the composition of which contains metals of the platinum group (platinum and palladium) and the compound composed of oxides of metals with specific surface of no less than 50 m2/g (oxides of zirconium, cerium and the aluminum taken in the certain ratio). The catalyst is fixed on the inertial carrier made out of oxides of metals with a specific surface area of 1-10 m2/g (cordierite). The total contents of platinum and a palladium makes 0.5-5.0 % from the mass of the composition, and platinum and palladium are in the ratio of(in mass %): 30:70-100:0. Aluminum, cerium and zirconium oxides are taken in the ratio of (in mass %): 80:20:0-30:60:20. The purified gas is passing gate through the reactor, in which the catalyst is loaded, at the temperature of 170-190°C. The method ensures reduction of the contents of the methane admixture in the inert gas from with 40-0.2·10-4 % of the volume up to the value of no more than 0.1·10-4 % of the volume at presence of oxygen and nitrogen at the level of 1.0-20·10-4 % of the volume.
EFFECT: the invention method ensures reduction of the contents of the methane admixture in the inert gas in the acceptable amount.