FI59354B - FOERFARANDE FOER IMPREGNERING OCH LASYRERING AV VIRKE MED SKYDDS- OCH FAERGAEMNEN - Google Patents

Description

E25F7] [Bl (11) MONTHLY PUBLICATION, g, r, TCI A lJ l 'UTLÄGGNI NGSSKRIFT S 7 JO 4 C ^ 4S) Patent sySmvlfcy 10 03 1931 Patent meridelat V' V (51) Kv.ik.3 / int.a.3 B 27 K 3/52 FINLAND - FINLAND (21) P »t * nttlh« lwmgii - PtcmtamOlinlnf 760169 (22) H * k «ml» pllvt - AnaSknlngtdtf 26.01.76 '' (13) Alkupilvt — GlMgkattd ·· 26.01.76 (41) Tullut lulkiMksi - Blhrit afUntllg ρτ 07 77 MMIt]. nUMrlMM «Λ f. -

Patent · och raglataratyrataan v 1 AmMcm utia | d och mi ^ kriftm puUicarad 30. oli. 81 (32) (33) (31) PjT * · ** / * tuolk # u «—Baflrd priori» * (71) Saastamoinen ühymä Oy, 70100 Kuopio 10, Finland-Finland (FI) (72) Olli Airaksinen, Pentti Perkiömäki, Suomi-Finland (FI) (7 * 0 Leitzinger Oy (5ä) Method for impregnation and gluing of wood with preservatives and dyes - Förfarande för impregnering och lasyrering av virke med skydds- och färgämnen

A method of impregnating and glazing timber with preservatives and dyes, wherein the solvent with the preservatives mixed therein is introduced into an impregnation cylinder in which the timber is arranged so that spacers and fasteners are used between the pieces of wood to be impregnated. , followed by the introduction of a heated oil at a temperature exceeding the boiling point of the solvent, whereby most of the solvent liquid remaining in the wood is removed, whereby the evaporated solvent is collected through the condenser back to the process to provide a closed circuit.

Such a method is known, for example, from Finnish Patent No. 45,626, in which a water-soluble impregnating agent is used and the timber is dried in an impregnation cylinder with oil at a temperature of about 60-90 ° C under reduced pressure, the oil is heated by heating elements in the impregnation cylinder. The patent states that rapid drying of the timber is not possible without a vacuum and it has further been proposed that the dyeing of the timber is carried out at the same time by means of a dye mixed with drying oil. Disadvantages of this known method include, firstly, the vacuum required during the drying step 59354 and, secondly, the long time required to heat a large amount of drying oil, as well as high-power heating elements. Also, arranging the dye in connection with the drying oil is not a successful solution, because in this case too many incompatible substances come into contact with each other, which limits the choice of the saturating solvent and the drying oil with a view to the most efficient evaporation of the solvent. The same drawbacks regarding the arrangement of the vacuum, the long heating time with the required large heating elements and the limitation caused by the dye mixed with the oil in the choice of solvent and drying oil are also related to the impregnation and annealing method known from Finnish patent application 753217. In the method known from Finnish patent application No. 3199/70, it has been proposed to use water vapor as a heated medium for removing the solvent of the impregnating liquid. However, the problem is to separate the water vapor and the evaporated solvent so that the solvent can be returned to the process. In addition, water vapor increases the moisture content of the wood to some extent. Above all, the efficiency of the system is poor and a long drying time is required.

The object of the invention is to provide an improved method of the above-mentioned type for impregnating wood with preservatives without the above-mentioned drawbacks. The method of the invention should be fast and efficient and feasible with simple and inexpensive equipment. In addition, the method according to the invention should enhance and speed up the post-impregnation sounding, which is understood as staining the wood so that the structure of the wood remains visible. In the method according to the invention, the use of water must be completely avoided, because the presence of water causes dimensional changes and distortions in the timber. In this case, the method according to the invention can optionally be used for impregnating dimensionally accurate finished products assembled by gluing or otherwise.

These objects are achieved and the requirements are met on the basis of the method characteristics set forth in the appended claim 1.

In the following, the invention will be described in more detail with reference to the accompanying drawings, in which Figure 1 shows a diagram of a device according to the invention seen from the side.

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Figure 2 shows a schematic side view of a further processing part for dyeing, i.e. dyeing, related to the device according to the invention.

The device comprises an impregnation cylinder 1 provided with an openable end 1a and a pressure equalization dome Ib, as well as the necessary measuring devices, fittings and insulators. At the bottom of the impregnation cylinder 1 there is a perforated plate 2 and a liquid drain hood 3.

The impregnating liquid consisting of a solvent, e.g. methylene chloride and various preservatives dissolved therein, is kept in the tank 4. Since the solvent is easily volatile, the impregnating liquid tank 4 is provided with a cooling piping 4a.

The tank 5 contains drying or distillation oil, which may be, for example, linseed oil. This is used to remove the solvent of the impregnating agent from the wood, as will be described in more detail later.

Reference numeral 6 denotes a leveling tank equipped with a filter screen. The drying oil is circulated through the leveling pipe 7 and the tank 6 by means of the drain pump 12 and further along the pipe 5d to the tank 5.

The drying oil is kept at a temperature above the boiling point of the impregnating liquid solvent by means of a heat exchanger 8. This takes place when the heating circulation pump 9 circulates the oil either via pipes 5a and 5b in a closed circuit to the tank 5 or along the pipe 5c to the impregnation cylinder 1. It is essential that the entire drying oil is kept at a high temperature so that no large oil is generated. delay time and no need for high power heat exchangers.

With the filling and draining pump 10, the impregnation cylinder 1 can be quickly filled and emptied alternately with impregnating liquid and drying oil.

With the low-supply and high-pressure pressure pump 11, the impregnating liquid can be fed to the filled, pressurized impregnating cylinder 1 as the impregnating liquid is absorbed into the wood. In addition, the pump 11 can be used in the final stage of impregnating liquid removal to remove residual liquid back to the tank 4, and further the pump 11 can be used to circulate the impregnating liquid through the filter 18, so that contaminants

When the impregnation step is completed and the impregnation liquid is removed from the impregnation cylinder 1, hot drying oil is pumped into the impregnation cylinder 1, which is kept in a continuous circulation through pipelines 5a, 5c, 7 and 5d by pumps 9 and 12. impregnation cylinder 1 and the timber therein. When the drying oil raises the temperature of the wood above the boiling point of the solvent, evaporation of the solvent from the wood results, whereby the solvent enters the drying oil, partly mixing and dissolving in it and partly bubbles directly through it. Due to the high temperature of the drying oil, the solvent mixed and dissolved in it also tends to evaporate rapidly from the drying oil. This solvent volatile from the drying oil is collected by pipes 20a, 20c and 20b which join the pipe 20 leading to the condenser 13, where the evaporated solvent is condensed into a liquid state. The solvent then enters the storage tank 14, which is dimensioned to correspond to e.g. the amount of solvent in one drying step. From the storage tank 14, the pure solvent is fed to a measuring and mixing device 15, where a certain amount of preservative concentrates is mixed with the solvent from the sealing container 16. The solvent transport tank 17 is replaced by the solvent

Figure 2 shows an apparatus for further treating impregnated timber with dyes so that the surface of the timber is made to the desired color, however, so that the causes of the wood remain visible. This is called hearing. The timber is loaded onto carriages 21, with which it can be pushed into and out of the impregnation cylinder 1. In this case, 1 or more tracks 22 are arranged which are transverse to the track of the carriages 21, which may consist of e.g. a roller system. A drying tunnel 23 with e.g. hot air blowing is arranged on this track 22. This is followed by a sounding device in which the timber is immersed in a dye solution in the sounding basin 24. Due to the fact that the wood is very hot after the drying oil treatment, e.g. about 100 ° C, the dye dries very quickly, which is further facilitated by the fact that the oil-surfaced wood does not absorb the water of the dye solution. Thus, finished, gutted and dry timber is available from the roll track 25 following the sounding device.

The operation of the above device is further described below. The carriages 21 loaded with pieces of wood are pushed into the impregnation cylinder 1 and locked in place. The end of the cylinder la is closed. The filling and draining pump 10 is started, before which the valve positions are selected so that the impregnation liquid flows from the tank 4 to the impregnation cylinder 1 through the pipes 4b and 4c. In this case, the flow takes place below the perforated plate 2, whereby the perforated plate 2 converts the flow rate of the liquid into a uniform rise of the liquid surface through the perforated plate 2. This has the advantage that the fluid forces on the stacked loads are kept to a minimum and do not tend to dissipate the loads. When the impregnation liquid reaches the pressure equalization dome Ib, the pump 10 stops and the inlet valve 4d and the air valve le close. The pressure pump 11 starts and maintains a pressure of 7 to 12 kp in the impregnation cylinder 1. The impregnation time depends on the desired impregnation depth. During impregnation, about 300 1 / m of wood is absorbed into the wood. At the end of the impregnation phase, the pressure pump 11 stops and the drain pump 10 starts operating by pushing the impregnating liquid in the cylinder 1 back into the storage tank 4. During the emptying phase, the perforated plate 2 acts as a screen The pressure pump 11 can also filter the liquid of the storage tank 4 by passing it through the filter 18, and in addition, the pressure pump 11 is also used to drain the system of the impregnating liquid.

The solvent liquid absorbed into the wood during impregnation must then be removed from the wood by about 300 1 / m of wood. Previously known devices have always used a vacuum for this purpose. In the invention, however, this is done with a normal pressure drying or distillation oil. The temperature of the drying oil in the tank 5, e.g. linseed oil, is about 40 to 100 ° C. With the filling pump 10, the drying oil is pressed from the tank 5 through the pipes 5e and 4c into the cylinder 1. Up to the level of the leveling pipe 7. The drying oil entering cylinder 1 immediately begins to evaporate a solvent in the wood such as methylene chloride. The aim is to raise the temperature of the timber in cylinder 1 to 40-100 ° C as soon as possible. This temperature rise takes place as follows. The heat circulation pump 9 sucks oil from the tank 5 through the pipe 5a and presses it through the filter 19 into the heat exchanger 8, from where it enters the cylinder 1 along the pipe 5c. The oil is thus filtered in connection with the heating of the oil. The significance of efficient filtration is that the sawdust and chips that come with the timber are removed and do not remain on the surface of the timber as spots that interfere with the appearance. In order to provide continuous heating, the cylinder 1 is provided with a (overflow) leveling pipe 7, along which the oil flows into the leveling tank 6, from which the oil is pumped back to the storage tank 5. The leveling system 7 also aims to prevent the impregnation cylinder 1 The purpose of the air space and free oil surface thus formed is to promote the evaporation of methylene chloride from the oil. During this drying or distillation step, which takes about 100 to 120 minutes, for example, at full saturation, 90% of the methylene chloride is recovered. This is mainly based on the fact that the high temperature drying oil evaporates (boils) the methylene chloride from the wood, whereby the methylene chloride is partially mixed with the oil. Evaporation of methylene chloride from the drying oil is arranged to take place in the air space of the impregnation cylinder 1 in the leveling tank 6 and in the drying oil tank 5, evaporation takes place continuously throughout the day. Condensation and return of the evaporated solvent back to the process in a completely closed loop has already been described above. At the end of the drying step, the drain pump 10 empties the cylinder 1 and pushes the drying oil back into the storage tank 5. The final discharge takes place by means of the drain pump 12 from the drain hood 3. After emptying, the end door 1a is opened and the carriages 21 are pulled out.

For sounding, spacers are used between the pieces of timber to keep the pieces of wood apart. For impregnation, this arrangement is not necessary, but also to some extent speeds up the impregnation process. The wood goods benches on the carriages 21 are pushed onto the rollers 22. A drying tunnel 23 is built on the rollers to dry the linseed oil from the wood surface. The circulating hot air flow provides even drying. The dried stacks are pushed one at a time into the elevator 24 of the sounding basin, where they are printed in the sounding color. The sonication staining takes about 0.5 minutes, after which the stacks are lifted by elevator. The oil in the wood prevents the water in the sounding liquid from being absorbed into the wood, and the temperature of the trees at 40 to 100 ° C causes the aqueous sounding agent to dry very quickly.

Claims (2)

59354 A method for impregnating and gluing timber with preservatives and dyes, in which the solvent mixed with the preservatives is introduced into an impregnation cylinder (1) in which the timber is arranged so that spacers and fasteners are used to separate the pieces of wood, and after a certain pressure impregnation time, the impregnating liquid is removed from the tank, to which a heated oil is then introduced, the temperature of which exceeds the boiling point of the solvent, removing most of the solvent in the storage tank (5) at a value exceeding the boiling point of the solvent and the temperature of the oil is controlled by recirculation through the heat exchanger (8) either from the impregnation cylinder (1) or from the oil storage tank (5), and that the impregnating fluid solvent is evaporated from the normal pressure drying oil by forming free evaporation surfaces in both the impregnation cylinder (1) and the oil storage tank (5) and possibly an oil circuit (100) C, the oily timber is immediately passed from the impregnation cylinder (1) through the drying tunnel (23) to the annealing device, where it is immersed in the dye solution in the annealing basin (24). Method according to Claim 1, characterized in that after the impregnation cylinder (1) is filled with drying oil, the circulation of the drying oil via the leveling pipe (7) back to the storage tank (5) and from there via the heat exchanger (8) to the impregnation cylinder (1).