Process and design improvements for retrofitting conventional wood plants

Abstract

Retrofitting an existing conventional southern yellow pine (SYP) lumber pressure treatment plant that pre-impregnates wood with unsustainable chemicals to use an environmentally friendly sodium silicate formulation. The retrofit includes adding a heated storage tank for the solution of the silicate solution, adding a heater to the existing storage tank, and a delivery line capable of handling a high pH viscous solution between at least the pre-existing vacuum pressure impregnation tank and the added or existing heated storage tank, a CO2 storage tank with an associated vaporizer and CO2 recovery system, associated lines to and from the pre-existing vacuum pressure impregnation tank and the CO2 storage tank and the CO2 recovery system, pumps for circulating the solution, and insulation and coating in one or more of the tanks and lines, heat tracing at all level indicators, and insertion of heating coils into the working tank, and may include installing a thermal management system.

Description

Technical Field

[0001] The present disclosure relates to converting an existing conventional southern pine (SYP) wood pressure treatment plant that pre-impregnates wood with unsustainable chemicals such as CA (copper azole), CCA (chromated copper arsenate), and ACQ (alkaline copper quaternary) into a plant for treating wood with an environmentally friendly sodium silicate formulation or other sustainable formulation. Wood means engineered wood such as mass timber such as dimension lumber, plywood, LVL (laminated veneer lumber), OSB (oriented strand board), and CLT (cross-laminated timber), as well as related products.

Background Art

[0002] Wood is one of the oldest building materials used in human civilization due to its strength, availability, and performance characteristics. Despite these characteristics, wood is damaged due to its low resistance to long-term wet conditions and to insects, fungi, and other biological attacks. As a result of this susceptibility, treatments are applied to wood to improve its resistance to insects, fire, and environmental conditions. These treatments have traditionally been in the form of metals or other non-environmentally friendly chemicals such as CA (copper azole), CCA (chromated copper arsenate), and ACQ (alkaline copper quaternary), and in the case of fire retardancy enhancement, OPFR (organic phosphorus flame retardants), as well as chemicals such as ammonium phosphate and ammonium borate.

[0003] Figure 3 shows a traditional lumber pressure treatment plant used in traditional processing processes. Traditional lumber pressure treatment plants impregnate conventional Southern Pine (SYP) lumber and plywood with unsustainable chemicals. The plant includes a log receiving area 310 where the lumber and plywood are received. Preferably, the logs, plywood, or related forest products are received in standard dimensional lumber sizes and no further milling or cutting is required. Alternatively, there may be subsequent milling or cutting steps after the lumber or plywood is received. The first processing is carried out in a vacuum pressure impregnation vessel 320. The impregnation vessel 320 is also commonly referred to as a reactor or autoclave. After vacuum pressure impregnation, the lumber is moved to a storage and conditioning area 330. The next area is a kiln 340 where the lumber is dried. The lumber is moved by an inclined hoist 350, which is a device for lifting the lumber by tilting and lifting the stack. After the lumber is dried, the lumber is labeled and packaged at a labeling and packaging station 360 and sent to a storage area 370 for storage and shipping.

[0004] Plywood is processed in a similar manner where the bundled plywood panels flow on a conveyor or are moved to the autoclave by a forklift. After processing in the autoclave, the plywood is moved to a drying kiln and then to labeling, packaging, and shipping. SUMMARY OF THE INVENTION

[0005] The process of impregnating with unsustainable chemicals such as copper arsenate chromate is a standard practice in the wood industry. The chemical formulations are fluids with low viscosity and are easily absorbed by wood, and thus the manufacturing processes used for them require less demanding application processes than the process applications described below for sodium silicate ((Na2O)x·SiO2) and related metal silicate-based solutions. Therefore, to adapt existing wood processing plant reactors to the requirements of sodium silicate solutions, processing equipment capable of handling polar, caustic, aqueous solutions that may have some non-Newtonian characteristics for impregnating the wood is required. A further feature in the sustainable process using sodium silicate is that the sodium silicate must be cured to form an adhesive solid, which is achieved either by delivering CO2 to lower the pH of the impregnating solution to less than about 9 or by another suitable method.

[0006] There is a need to convert existing sawmill pressure treatment plants into cost-effective, environmentally friendly, i.e., fully environmentally conscious plants for treating wood that can eliminate toxic chemicals, enhance strength properties, and provide increased fire resistance ratings that meet or exceed current internationally and domestically recognized building and building material standards while maintaining other desirable properties such as resistance to decay, bacteria, and insects and also providing other desirable properties without using toxic chemicals. The converted sawmill treatment plant can treat wood according to the method disclosed in U.S. Patent Publication No. 2021 / 0170623 entitled Green Process for Modifying Wood, the content of which is incorporated by reference.

[0007] The method for processing lumber begins with the insertion of the kiln strips into the lumber package. Alternatively, the method is carried out without inserting the kiln strips into the lumber package. Next, the lumber package is fixed with straps and then the impregnation process can be started in an autoclave. When the lumber is inserted into the autoclave, the autoclave is placed under vacuum. According to one aspect of the present invention, the degree of vacuum is -28 to -30 psi for about 30 minutes. Other vacuums can be drawn from -15 psi to -50 psi. The process chemicals disclosed in the aforementioned patent publication are then inserted into the autoclave at high pressure and high temperature for the required time. Next, the wood in the autoclave is evacuated again and then filled with carbon dioxide and kept under pressure for a period ranging from 20 minutes to 24 hours. The reactor is not heated. However, the silicate solution can use a wider temperature range of 50 to 80 °C, but is preheated to 60 to 70 °C. The once-introduced solution is then pressurized at 190 psi for 90 minutes, followed by evacuation at -28 psi for about 5 minutes and pressurization to 50 psi for 20 to 30 minutes. These ranges are exemplary, but wider ranges are conceivable. Carbon dioxide is then removed by placing the autoclave under vacuum again. When the vacuum is released, the lumber is removed from the autoclave and dried for 24 to 48 hours. The lumber is then reinserted into the autoclave. A vacuum is drawn and the process chemicals are injected into the autoclave for the second time at high pressure and high temperature. The chemicals are then removed by evacuating the autoclave, and subsequently, a second treatment with CO2 can be performed, or alternatively, it can be removed from the autoclave and kiln dried at about 50 °C for 5 to 7 days. It should be noted that the temperature and cycle time may vary depending on the environmental conditions during drying, the load size, and the wood size. After drying, the kiln strips are removed and the lumber is brushed and stamped. The brushed and stamped lumber is then ready for sale on the market.

[0008] The present disclosure presents a cost-effective solution for converting or reusing existing sawmill plants by applying new technological changes to pre-existing plants. This is not only cost-effective but also, when the reactor is thoroughly cleaned and improved, can eliminate potentially dangerous waste conditions in existing plants.

[0009] A wood pressure treatment plant is configured to carry out a wood vacuum pressure impregnation process. The plant to be improved has a pre-existing vacuum pressure impregnation tank, supply lines, vacuum pumps, and a wood transport system. For non-toxic and environmentally sustainable processing, at least the following additions and improvements are made to the existing plant: Installing an autoclave capable of handling a silicate solution pressurized at approximately 190 psi if not already present, Adding one or more heated storage tanks for the solution of the silicate solution, Adding and / or replacing delivery lines capable of handling a high pH viscous solution at high temperatures, One or more CO2 storage tanks each having an associated vaporizer and delivery line, A CO2 recovery system, One or more pumps and filter pumps capable of handling a high pH viscous solution, Adding a thermal management system comprising insulation and cladding materials, temperature tracing in all vessels and, if feasible, in the delivery lines, level indicators which are typically magnetic float type indicators, and heating coils inserted into the working tanks.

[0010] According to one aspect of the invention, a process control information system configured to manage, monitor, and record the wood vacuum pressure impregnation process and other related processes is installed. The process control information system is further configured to optimize key performance indicators including silicate solution temperature, autoclave pressure, and the duration of the vacuum, pressurization, and carbon dioxide cycles.

[0011] According to one aspect of the present invention, software is added to an existing or upgraded programmable logic controller (PLC) system and functions in conjunction with digital and mechanical recording devices to track, record, and analyze process variables of a sodium silicate solution in real time. Process variables include solution temperature, autoclave pressure, amount of solution utilized, storage tank and processing autoclave temperature, duration of each stage of the process, and correlations between these variables. The software provides collected data that can be used to further optimize the process.

[0012] The sodium silicate solution requires processing equipment that can handle a polar, caustic, aqueous solution that may have some non-Newtonian properties for impregnating wood.

[0013] According to one aspect of the present invention, the pH of the silicate solution is typically between 10 and 12.

[0014] According to one aspect of the present invention, the thermal insulation material, which prevents heat loss and functions as an actual thermal insulator, is typically glass fiber, and the coating material is a protective coating over the insulation material and is typically corrugated metal.

[0015] According to one aspect of the present invention, components are added so that a two-stage impregnation process can be carried out.

[0016] According to one aspect of the present invention, one or more kilns, which are in-line kilns for drying silicate-impregnated wood, are installed.

[0017] According to one aspect of the present invention, an in-line mechanical stress measurement system is added for quantification of silicate uptake for lumber after the impregnation process. There are several alternatives for implementing the stress measurement system. The first alternative is a device configured to measure the density of wood by taking out a small sample and plotting the density. As an example, a drill and related components typically used to test poles and related structures are mentioned. The second alternative is an industrial-scale lumber strength measurement device that uses X-rays and other imaging techniques to evaluate the lumber. This device can determine the density of both the finished product, grade the incoming lumber, and preferentially transfer the low-density wood to impregnation. This device can also perform natural frequency analysis. Another alternative is a system that uses acoustic transmission, which is generally used to evaluate the soundness of wood. Such a system can be adapted to analyze the filled silicate composite because the silicate filler changes the density of the wood and can be measured nondestructively by this technique. Additionally, or alternatively, bending stress measurement can be used.

[0018] According to one aspect of the present invention, a hyperspectral analyzer system, an X-ray analyzer, or an acoustic analyzer system is added so that the lumber can be analyzed for wood form analysis both before and after impregnation. Hyperspectral analysis measures spectral data, typically in the near-infrared of wood, over various wavelengths to determine the surface composition of the product.

[0019] According to one aspect of the present invention, a natural frequency measurement system is added for quantification of silicate uptake. The natural frequency is a characteristic vibration mode of the material. This is obtained in much the same way as used to resonate a tuning fork. The wood beam is struck and the resulting frequency is measured.

[0020] According to one aspect of the present invention, a multi-input solution dispensing system is added upstream of the supply line to the impregnation tank for formulation control and quantification capable of delivering two or more impregnation charges.

[0021] According to one aspect of the present invention, a spray and / or immersion delivery system configured to dispense aqueous solutions containing high pH, neutral pH, and low pH solutions is included both before and after the impregnation step. The continuous spray equipment includes a conveyor or the like, and the wood passes under a plurality of spray heads for treatment. The immersion delivery system includes a tank in which the wood is immersed.

[0022] According to one aspect of the present invention, software is used in a facility to interface with digital and mechanical recording devices programmed to track, record, and analyze in real time the main process variables including solution temperature, autoclave pressure, the amount of solution utilized, storage tank and processing autoclave temperature, the duration of each stage of the process, and the correlations between these variables.

[0023] The present invention will be described in more detail based on exemplary embodiments.

Brief Description of the Drawings

[0024]

Figure 1

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Figure 5A

Figure 5B

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Best Mode for Carrying Out the Invention

[0025] The modified southern pine wood pressure treatment plant uses a non-toxic and environmentally sustainable process to improve wood using a sodium silicate formulation or other environmentally friendly formulations. An exemplary implementation of the treatment process is shown in FIG. 1. The impregnating liquid is prepared by mixing a silicate mixture with water in a supply tank. Optionally, other impregnation efficiency inducing compounds including boric acid, sodium borate, sodium hydroxide, or a surfactant may be added to this supply tank. The final solution preparation can include a plurality of additives for treatment. The mixture can be pumped to a working tank for heating and stirring. Once the size of the lumber is selected, the untreated lumber is placed in an impregnation vessel / autoclave. The autoclave is placed under vacuum and then the liquid mixture from the working tank is added to the impregnation vessel / autoclave. When the liquid mixture is added, pressure is applied to the autoclave. Next, the pressure is reduced and the impregnation vessel / autoclave is placed under vacuum. Optionally, a second impregnation step is included involving adding a second, typically higher concentration, impregnation solution to the autoclave. After the impregnation vessel / autoclave is placed under vacuum, gaseous carbon dioxide from a carbon dioxide processing unit is introduced into the impregnation vessel / autoclave. Next, the treated lumber is removed from the impregnation vessel / autoclave.

[0026] According to one aspect of the present invention, certain quality control tests are performed to evaluate the treatment process. These processes have been developed and customized to know whether impregnation has been successful. The treated lumber is then heated and dried using a conventional lumber kiln.

[0027] According to one aspect of the present invention, a second impregnation process is performed. This second impregnation can be performed using the same equipment or using additional processing equipment. Once treated, the lumber is filled into a pressure vessel that is subjected to vacuum, pressure, and vacuum cycles. The lumber is then dried twice.

[0028] Surface cleaning is performed on the processed lumber. Next, the processed lumber can undergo quality control analysis. Subsequently, the processed lumber is stamped, banded, and packaged for shipment.

[0029] To carry out the impregnation process, it is necessary to improve an existing conventional southern pine (SYP) lumber pressure treatment plant. Conventional lumber pressure treatment plants typically include a lumber infeed chain, a chemical storage system, a water storage system, a treatment chemical blending tank, a supply product tank, an autoclave where lumber impregnation takes place, and a drip tray for product drainage.

[0030] Preferably, conventional equipment for the conventional treatment process is used for upgrading and improvement. Alternatively, the conventional equipment can be replaced.

[0031] A unloading station for large product delivery tankers with associated piping is added. New or existing chemical storage tanks are insulated with insulating materials and coated with protective materials. The insulating and coating materials are also added to the supply lines between the storage tank and the blending tank, the blending tank, and the product supply lines to and from the working tank and to and from the autoclave.

[0032] According to one aspect of the present invention, heating coils are installed in each of the working tanks to heat the products. The heating coils are preferably horizontal coils inserted into the containers. Level indicator heat tracing is added or upgraded to each of the working tanks, blending tanks, autoclaves, and chemical supply tanks. The change or addition of the heat tracing components is a preventive measure because typical level indicators are magnetic float indicators and are affected by high-viscosity chemical solutions.

[0033] According to one aspect of the present invention, an updated tote system for adding special chemicals to the main blending tank is installed. A tote is a large plastic container that holds liquid. During operation, the supply line is inserted into the tote and the liquid is pumped from the tote. Further, a digitally controlled chemical feeder system can be installed and used to achieve more accurate and efficient blending of special chemicals.

[0034] The pumps and filters of the conventional plant are also upgraded. The pumps not only circulate the processing solution between the storage tank and the processing vessel, but also circulate the processing solution within the tank and the vessel. The enhanced pump is configured to pump a high-viscosity chemical solution to the working tank. The pump preferably uses a filter sock type filter. According to one aspect of the present invention, the filter medium is a 200-micron sock.

[0035] A carbon dioxide storage tank and associated vaporizer are installed, with supply and return lines to the autoclave. In addition, one or more double plug block valves with actuators are installed in these two lines.

[0036] According to one aspect of the present invention, the piping within the conventional factory is re-routed to allow for unobstructed flow of higher-viscosity silicate solutions. This re-routing can vary depending on the specific design of the existing plant, but as a priority, it should remove flow restrictions, introduce no unnecessary turbulence, and be as direct as possible.

[0037] The existing plant piping preferably remains as is, but as described above, changes are made to the working tank filter and pump system. In addition, all piping is insulated and coated to minimize heat loss and is suitable for operating temperatures of 50°C to 100°C.

[0038] A stirrer is installed in the product working tank. An exemplary stirrer is shown in FIG. 4. The stirrer includes a motor 1, a gearbox 2, seal assemblies 3, 4, a drive shaft 5, and an impeller 6. As shown, the impeller is driven clockwise. FIGS. 5A and 5B show the tank with the stirrer installed. Preferably, the stirrer is a large paddle-type stirrer that provides a homogeneous chemical product mixture. The stirring and pump recirculation system provides a well-mixed formulation for the impregnation process.

[0039] To maintain the operating temperature, as discussed above, heating coils, as well as insulation and cladding materials, are added. The heating coils maintain the chemical mixture, referred to as the product, at a temperature of approximately 50 - 95 °C. Some steps of the impregnation system may use chemicals at room temperature, but for steps that require heated chemicals, the provision of insulation results in higher energy efficiency, thus providing more consistent process results and reducing product material losses.

[0040] Carbon dioxide gas is used in a process to precipitate the chemicals added to the wood by lowering the pH. Accordingly, a CO2 gas storage delivery and recovery system is installed. Along with the necessary vaporizers, a liquid carbon dioxide storage container is installed. A 2-inch piping system is installed and supplied not only to the upper rear region of the autoclave but also to the return vent line.

[0041] According to one aspect of the present invention, an upgrade to a plant programmable logic controller (PLC) system is also installed. An existing PLC control system can be used, but it needs to be upgraded with logic changes, addition of new control loops, and appropriate software upgrades. The upgrade is provided at least partially to the temperature display and control system. This upgrade is important for steady-state operation where multiple impregnation cycles are being performed. To continuously add fresh chemicals to the process, a rapid heater response is required, and this logic is provided by the upgraded PLC.

[0042] According to one aspect of the present invention, software is added to a programmable logic controller (PLC) system and functions in conjunction with digital and mechanical recording devices programmed to track, record, and analyze major process variables in real time. Process variables include solution temperature, autoclave pressure, amount of solution utilized, storage tank and processing autoclave temperature, duration of each stage of the process, and correlations between these variables. The collected data can be used to further optimize the process.

[0043] In conventional processing processes, lumber is stacked in "packets" with one layer on top of another. In the case of improved plants and processes, a kiln strip is inserted prior to the processing process. The kiln strip serves two purposes. First, the kiln strip ensures that the lumber is fully impregnated by providing space between the layers. Second, the kiln strip enables the product to be kiln dried to reach the KD19 standard (kiln dried to a moisture content of 19%).

[0044] This improved process using a kiln strip includes receiving the wood, inserting the kiln strip, strapping the lumber packets, performing one or two stage impregnation operations, kiln drying the material, disassembling the packets, removing the kiln strip, and preparing the final lumber packets for shipping.

[0045] Figure 2 is a schematic process layout of a converted wood processing plant for the wood processing process of Figure 1. The wood processing plant has a log receiving section 210, which may or may not be the same as the storage and shipping area 290. The converted wood processing plant includes one, two, or more vacuum pressure impregnation vessels 220, 240. If space permits, two or more vacuum pressure impregnation vessels 220, 240 are installed.

[0046] The first pressure impregnation vessel 220 is coupled to the silicate storage vessel 222 via the blend tank 224. There is also a vacuum source 226 and a carbon dioxide storage 228 coupled to the first pressure impregnation vessel 220. A storage and adaptation area 230 is provided for the lumber processed in the first pressure impregnation vessel 220.

[0047] The second pressure impregnation vessel 240 is coupled to the silicate storage vessel 242 via the blend tank 244. There is also a vacuum source 246 and a carbon dioxide storage 248 coupled to the first pressure impregnation vessel 240. Note that the vacuum source 226 can be the same as the vacuum source 246. Further, the carbon dioxide storage 228 can be the same as the carbon dioxide storage 248. Piping can be provided such that only a single vacuum source and / or carbon dioxide storage is required.

[0048] The kiln 260 in which the processed lumber is dried is provided with a storage 250 for kiln drying. The tilt hoist 270 is used to lift and tilt the lumber. A labeling and packaging station 280, and a storage area 290 for shipping are provided. As described above, the storage area 290 can be the same as or different from the log receiving area 210.

[0049] Figure 6 is an overview of the steps for converting and / or updating a processing plant. The steps can be carried out in any order, but are presented according to one aspect of the invention. In step 110, a heated storage tank for a solution of silicic acid solution is added and / or a heater is added to an existing storage tank. A delivery line capable of handling a high ph viscous solution is installed in step 120 between at least a pre-existing vacuum pressure impregnation tank and an added or existing heated storage tank. In step 130, a CO2 storage tank with an associated vaporizer and CO2 recovery system is added. In step 140, associated lines to and from the existing vacuum pressure impregnation tank and CO2 storage tank and CO2 recovery system are installed. Next, pumps are installed in step 150 to circulate the solution. Finally, in step 160, a thermal management system is installed including one or more of insulation and coating in one or more of the tanks and lines, heat tracing at all level indicators, and insertion of heating coils into the working tank.

[0050] Accordingly, while the basic novel features of the invention applicable to its preferred embodiments have been illustrated, described, and pointed out, it will be understood that various omissions and substitutions and changes in the form and detail of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, all combinations of those elements and / or method steps that perform substantially the same function in substantially the same way to achieve the same result are expressly intended to be within the scope of the present disclosure. Further, it should be recognized that structures and / or elements and / or method steps illustrated and / or described in connection with any disclosed form or embodiment of the invention may be incorporated, as a general matter of design choice, into any other disclosed or proposed form or embodiment. Accordingly, it is intended to be limited only as indicated by the scope of the claims appended hereto.

Claims

1. A method for upgrading a lumber vacuum pressure impregnation process plant having a pre-existing vacuum pressure impregnation tank, a supply line, an original vacuum pump, and a lumber transportation system, comprising: adding at least one of a heating storage tank for a solution of silicic acid solution and adding a heater to an existing storage tank; installing a delivery line capable of handling a high pH viscous solution between at least the pre-existing vacuum pressure impregnation tank and the added or existing heating storage tank; Associated vaporizer and CO ２ CO with a recovery system ２ Installing a storage tank, and the pre-existing vacuum impregnation tank and the CO ２ storage tank and the CO ２ installing associated lines to and from the recovery system, installing a pump for circulating the solution; installing a thermal management system, wherein the thermal management system includes heat insulation and coating in one or more of the tanks and lines; heat tracing at all level indicators; and inserting a heating coil into the working tank. A method comprising the above.

2. The method for upgrading a lumber vacuum pressure impregnation process plant according to claim 1, further comprising installing a second vacuum pressure impregnation tank and an associated supply line.

3. The method for upgrading a lumber vacuum pressure impregnation process plant according to claim 2, further comprising upgrading or replacing the pre-existing vacuum pressure impregnation tank for the impregnation process of silicate-impregnated wood.

4. The method for upgrading a lumber vacuum pressure impregnation process plant according to claim 1, further comprising installing an in-line kiln for drying silicate-impregnated wood.

5. The method for upgrading a lumber vacuum pressure impregnation process plant according to claim 1, further comprising installing an in-line mechanical stress measurement system for quantifying silicate uptake.

6. The method for upgrading a lumber vacuum pressure impregnation process plant according to claim 1, further comprising installing a hyperspectral analyzer, an X-ray analyzer, or an acoustic analyzer system for wood morphology analysis.

7. The method for upgrading a lumber vacuum pressure impregnation process plant according to claim 1, further comprising installing a natural frequency measurement system configured to quantify silicate uptake.

8. The method of upgrading a lumber vacuum pressure impregnation process plant according to claim 1, further comprising installing a multi-input solution dispensing system before the supply line to the vacuum pressure impregnation tank, wherein the multi-input solution dispensing system is configured for formulation control, quantification, and delivering two or more impregnation charges.

9. The method of upgrading a lumber vacuum pressure impregnation process plant according to claim 1, further comprising installing a delivery system configured to dispense aqueous solutions of high pH, neutral pH, and low pH solutions before and after the impregnation step.

10. The method of upgrading a lumber vacuum pressure impregnation process plant according to claim 1, further comprising installing an immersion delivery system configured to dispense aqueous solutions of high pH, neutral pH, and low pH solutions before and after the impregnation step.

11. The method of upgrading a lumber vacuum pressure impregnation process plant according to claim 1, wherein at least one of the solutions is a high pH viscous solution.

12. The method of upgrading a lumber vacuum pressure impregnation process plant according to claim 6, wherein the hyperspectral analyzer system for wood morphology analysis is arranged for use before and after impregnation.

13. The method of upgrading a lumber vacuum pressure impregnation process plant according to claim 1, further comprising installing an autoclave configured to handle the silicic acid solution pressurized to at least 190 psi.

14. The method of upgrading a lumber vacuum pressure impregnation process plant according to claim 1, further comprising installing software for a controller configured to track, record, and analyze process variables of a sodium silicate solution, wherein the process variables include one or more of solution temperature, autoclave pressure, amount of solution utilized, storage tank temperature, treatment autoclave temperature, and duration of each stage of the process.

15. A plant for implementing a lumber vacuum pressure impregnation process, A lumber handling device configured to transport lumber from a receiving area to a plurality of stations, wherein the stations are A first vacuum pressure impregnation tank coupled to a first heated storage tank, a first blend tank, a first vacuum source, and a delivery line configured to handle a high pH viscous solution between at least the first vacuum pressure impregnation tank and the heated storage tank. At least one storage area. A second vacuum pressure impregnation container coupled to a second heated storage tank, a second blend tank, a second vacuum source, and a delivery line configured to handle a high pH viscous solution between at least the first vacuum pressure impregnation tank and the heated storage tank. Associated vaporizer, and CO coupled to at least said first and second vacuum impregnation vessels ２ At least one CO with a recovery system ２ Storage tank, and At least one kiln. At least a labeling station. At least one packaging station. A lumber handling device comprising at least a shipping station. A thermal management system, Insulation materials and coating materials in one or more of the containers, tanks, and lines. A thermal management system comprising a heat tracing sensor. A pump configured to circulate the solution A plant comprising.

16. A plant for implementing the lumber vacuum pressure impregnation process according to claim 15, further comprising an autoclave configured to handle a silicic acid solution pressurized to at least 190 psi.

17. A plant for implementing the lumber vacuum pressure impregnation process according to claim 15, further comprising a controller configured to track, record, and analyze process variables of a sodium silicate solution, the process variables including one or more of solution temperature, autoclave pressure, amount of solution utilized, storage tank temperature, processing autoclave temperature, and duration of each stage of the process.

18. A plant for implementing the lumber vacuum pressure impregnation process according to claim 17, wherein the controller is a programmable logic controller.

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