Process and design modifications to reform conventional wood factories

Abstract

The present invention provides a method for renovating an existing conventional Southern yellow pine (SYP) wood pressure treatment plant, which previously impregnates wood with non-sustainable chemicals, to use environmentally friendly sodium silicate formulations. The retrofit may include adding a heated storage tank for a solution of a siliceous solution and adding a heater to an existing storage tank; a conveying pipeline capable of treating the high-pH viscous solution is arranged at least between the previous vacuum pressure impregnation tank and the added or existing heating storage tank; mounting a CO2 storage tank with associated vaporizer and CO2 recovery system; a CO2 recovery system mounted to associated pipelines from the prior vacuum pressure impregnation tank and the CO2 storage tank and the CO2 recovery system; mounting a pump for circulating the solution; and installing a thermal management system comprising: thermal insulation and cladding on one or more of the tanks and pipelines, heat tracing on all the level indicators; and inserting the heating coil into the working tank.

Description

Technical Field

[0001] The present disclosure relates to converting existing conventional Southern Pine (SYP) lumber pressure treatment plants that previously impregnated lumber with unsustainable chemicals such as CA (copper azole), CCA (copper chromium arsenic) and ACQ (alkaline copper quaternary ammonium salt) to plants that treat lumber with environmentally friendly sodium silicate formulations or other sustainable formulations. Lumber refers to dimension lumber, plywood, engineered lumber such as LVL (laminated veneer lumber), OSB (oriented strand board) and mass timber including CLT (cross laminated timber) and 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 properties, wood can be damaged if it is exposed to wet conditions for a long time and due to its poor resistance to insect, fungal and other biological attacks. Due to this sensitivity, treatments are applied to wood to improve its durability to insects, flame retardancy and environmental conditions. These treatments traditionally take the form of metals or other non-environmentally friendly chemicals, such as CA (copper azole), CCA (copper chromium arsenic) and ACQ (alkaline copper quaternary ammonium salts), and in the case of flame retardant enhancement, OPFR (organophosphorus flame retardant), and chemicals such as ammonium phosphate and ammonium borate.

[0003] Figure 3 A conventional lumber pressure treatment plant used in conventional treatment processes is shown. Conventional lumber pressure treatment plants impregnate conventional southern pine (SYP) lumber lumber and plywood with unsustainable chemicals. The plant includes a timber receiving area 310, where timber and plywood are received. Preferably, the timber, plywood or related forest products are received in standard specification lumber sizes and do not require further milling or sawing. Alternatively, after the timber or plywood is received, there is a subsequent milling or sawing step. The first processing occurs at 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 timber is moved to a storage and adaptation area 330. The next area is a kiln 340, where the timber is dried. The timber is moved by a tilting crane 350, which is a device that lifts the timber by tilting the stack and lifting the stack. After the timber is dried, the timber is labeled and packaged at a labeling and packaging station 360 and sent to a storage area 370 for storage and shipment.

[0004] Plywood is processed in a similar manner, with bundles of plywood strips flowing on conveyor belts or moved to autoclaves by forklifts. After processing in the autoclave, the plywood is transferred to a drying kiln and then labeled, packaged, and shipped. Summary of the invention

[0005] The process of impregnation with unsustainable chemicals such as copper, chromium, and arsenic is standard practice in the wood industry. The chemicals are liquids with low viscosity and are easily absorbed by wood, and therefore, the manufacturing process for them requires a less demanding application process compared to the process application described below for sodium silicate (Na2O)x·SiO2 and related metal silicate-based solutions. Therefore, in order to adjust the existing wood processing plant reactors to meet the needs of sodium silicate solutions, processing equipment that can handle polar, corrosive aqueous solutions that may have some non-Newtonian properties is needed to impregnate wood. Another difference in the sustainable process using sodium silicate is that the sodium silicate must be solidified to form a cohesive solid, and this is achieved by CO2 delivery to reduce the pH of the impregnation solution or another suitable method to reduce it to below about 9.

[0006] There is a need to transform existing wood pressure treatment plants into cost-effective, environmentally friendly (i.e., all green) plants for treating wood that can eliminate toxic chemicals and provide enhanced strength properties, improved fire ratings that meet or exceed current internationally and nationally recognized building and construction material standards while maintaining other desired properties, such as resistance to decay, bacteria, and insects, while also providing other desired properties without the use of toxic chemicals. The transformed wood treatment plant is capable of treating wood according to the method disclosed in U.S. Patent Publication 2021 / 0170623, entitled "Green Process for Modifying Wood," the contents of which are incorporated by reference.

[0007] The method for processing forest wood begins with inserting kiln bars into the wood bales. Alternatively, the method can be performed without inserting kiln bars into the wood bales. Next, the wood bales are tied, and then the impregnation process can begin in the autoclave. Once the wood is inserted into the autoclave, the autoclave is placed under vacuum. According to one aspect of the present invention, the vacuum is -28psi to -30psi for about 30 minutes. Other vacuums can be drawn between -15psi and -50psi. Next, the process chemicals disclosed in the above patent disclosure are inserted into the autoclave at elevated pressure and elevated temperature for a necessary period of time. Next, the wood in the autoclave is vacuumed again, and then carbon dioxide is filled into the autoclave and allowed to remain under pressure for a period of time ranging from 20 minutes to 24 hours. The reactor is not heated. However, although a wider temperature range between 50°C and 80°C can be used, the silicate solution is preheated to 60°C to 70°C. Once the solution is introduced, pressurization is continued at 190 psi for 90 min, followed by vacuum at -28 psi for about 5 minutes, to be completed by pressurization to 50 psi for 20 to 30 min. Although these ranges are exemplary, wider ranges are conceivable. Carbon dioxide is then removed by placing the autoclave under vacuum again. Once the vacuum is released, the wood is taken out of the autoclave and allowed to dry for 24 to 48 hours. The wood is then reinserted into the autoclave. The vacuum is extracted and the process chemicals are injected into the autoclave for the second time at an elevated pressure and elevated temperature. The chemicals are then removed by extracting the vacuum on the autoclave, and then a second treatment with CO2 may be performed, or alternatively the chemicals are removed from the autoclave and kiln dried at about 50°C for a period of five to seven days. It should be noted that when drying, the temperature and cycle time may vary depending on environmental conditions, load size, and wood size. After drying, the kiln bars are removed and the wood is wire-drawn and stamped. Then, the wire-drawn and stamped wood can be marketed.

[0008] The present disclosure presents a cost-effective solution for remodeling or repurposing existing wood processing plants by making novel technical changes to prior plants. Not only is this cost-effective, but once the reactors are thoroughly cleaned and modified, potentially hazardous waste conditions at existing plants can be eliminated.

[0009] The wood pressure treatment plant is configured to perform a vacuum pressure impregnation process for wood. The plant to be modified has a pre-existing vacuum pressure impregnation tank, a feed line, a vacuum pump and a wood transport system. In order to achieve a non-toxic and environmentally sustainable process, at least the following additions and modifications are made to the existing plant:

[0010] Install an autoclave capable of handling a siliceous solution pressurized at approximately 190 psi (if one does not already exist);

[0011] adding one or more heated storage tanks for solution of the siliceous solution;

[0012] Adding and / or replacing transfer lines with transfer lines capable of handling high pH viscous solutions at elevated temperatures;

[0013] Add one or more CO2 storage tanks, each with an associated vaporizer and delivery lines;

[0014] CO2 recovery system;

[0015] One or more pumps capable of handling high pH viscous solutions and a filter pump; and

[0016] Thermal management system including insulation and blanketing on all vessels and, where applicable, transfer lines, temperature tracking level indicators (typically magnetic float type indicators), and heating coils inserted into the work tanks.

[0017] According to one aspect of the present invention, a process control information system is installed that is configured to manage, monitor and record the wood vacuum pressure impregnation process and other related processes. The process control information system is further configured to optimize key performance indicators, including silicate solution temperature, autoclave pressure, and vacuum, pressurization and carbon dioxide cycle durations.

[0018] According to one aspect of the invention, software is added to an existing or upgraded programmable logic controller (PLC) system to work in conjunction with digital and mechanical recording devices to track, record and analyze process variables of the sodium silicate solution in real time. The 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.

[0019] Sodium silicate solutions require processing equipment that can handle polar, corrosive aqueous solutions that may have some non-Newtonian properties to impregnate the wood.

[0020] According to one aspect of the invention, the pH of the silicate solution is typically between 10 and 12.

[0021] According to one aspect of the invention, the insulation, which is the material that prevents heat loss and serves as the actual insulation, is typically fiberglass, and the cladding is a protective coating over the insulation, typically corrugated metal.

[0022] According to one aspect of the invention, features are added so that a two-step impregnation process can be performed.

[0023] According to one aspect of the invention, one or more kilns are installed which are in-line kilns for drying silicate impregnated wood.

[0024] According to one aspect of the invention, an in-line machine stress measurement system is added to the wood after the impregnation step for silicate absorption quantification. There are several alternatives for implementing the stress measurement system. The first alternative is a device configured to measure the density of the wood by taking a small sample and plotting the density. Examples would include drills and related components typically used for test poles and related structures. The second alternative is an industrial-scale wood strength measurement device that uses X-rays and other imaging techniques to evaluate the wood. The device can determine the density of the finished product and grade the incoming wood to preferentially transfer lower density wood for impregnation. The device can also perform natural frequency analysis. Another alternative is a system using sound transmission, which is commonly used to assess the health of trees. Such a system can be suitable for analyzing filled silicate composites because the silicate filler will change the density of the wood and can be measured non-destructively by this technology. Additionally or alternatively, bending stress measurements can be used.

[0025] According to one aspect of the invention, the addition of a hyperspectral analyzer system, an x-ray analyzer, or an acoustic analyzer system allows the wood to be analyzed before and after impregnation for wood morphology analysis. Hyperspectral analysis measures spectral data across multiple wavelengths (typically at near infrared wavelengths for wood) to determine the surface composition of the product.

[0026] According to one aspect of the invention, a natural frequency measurement system is added for silicate absorption quantification. The natural frequency is the characteristic vibration mode of a material. It is obtained in much the same way as used to resonate a tuning fork. A wooden beam is struck and the resulting frequency is measured.

[0027] According to one aspect of the invention, a multi-input solution distribution system is added upstream of the feed line into the impregnation tank for formulation control and dosing, which is capable of delivering two or more impregnation charges.

[0028] According to one aspect of the invention, a spray and / or immersion delivery system is included that is configured to dispense aqueous solutions before and after the immersion step, the aqueous solutions including high, neutral and low pH solutions. The continuous spray arrangement will include a conveyor belt or the like, and the wood will pass under a plurality of spray heads for treating the wood. The immersion delivery system will include a tank into which the wood is immersed.

[0029] According to one aspect of the invention, software is used in a facility to work with digital and mechanical recording devices that are programmed to track, record and analyze in real time key process variables including solution temperature, autoclave pressure, amount of solution utilized, storage tank and processing autoclave temperatures, duration of each stage of the process, and correlations between these variables. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present invention will be described in more detail on the basis of exemplary embodiments. In the accompanying drawings:

[0031] Figure 1 is a flow chart illustrating an exemplary embodiment of a wood treatment process;

[0032] Figure 2 is used for Figure 1 Schematic layout of a modified wood processing plant for the wood modification process;

[0033] Figure 3 It is a schematic layout of an existing wood processing plant;

[0034] Figure 4 is an exemplary agitator;

[0035] Figure 5A and Figure 5B A tank with an agitator is shown; and

[0036] Figure 6 is a flow chart for modifying a treatment plant. DETAILED DESCRIPTION

[0037] The converted Southern Pine lumber pressure treatment facility uses a non-toxic and environmentally sustainable process for modifying the wood using sodium silicate formulations or other environmentally friendly formulations. Figure 1An exemplary embodiment of the treatment process is shown in . The impregnation liquid is prepared by mixing a silicate mixture with water in a feed tank. Optionally, boric acid, sodium borate, sodium hydroxide or other impregnation efficiency inducing compounds including surfactants can be added to the feed tank. The final solution preparation can include a variety of additives for treatment. The mixture can be pumped to a working tank for heating and stirring. Once the size of the wood is selected, the untreated wood is placed in an impregnation container / autoclave. The autoclave is placed under vacuum, and then the liquid mixture from the working tank is added to the impregnation container / autoclave. Once the liquid mixture is added, pressure is applied to the autoclave. Next, the pressure is reduced and the impregnation container / autoclave is placed under vacuum. Optionally, a second impregnation step is included, which involves adding a second, typically higher concentration, impregnation solution to the autoclave. After the impregnation container / autoclave is placed under vacuum, gaseous carbon dioxide from a carbon dioxide processing device is introduced into the impregnation container / autoclave. Next, the treated wood is taken out of the impregnation container / autoclave.

[0038] According to one aspect of the invention, certain quality control tests are performed to evaluate the treatment process. These processes are developed and customized to understand whether the impregnation was successful. The treated wood is then heated and dried using a conventional sawmill kiln.

[0039] According to one aspect of the invention, a second impregnation process is performed. This second impregnation can be performed in the same equipment or using additional processing equipment. The wood that has been treated once is loaded into a pressure vessel where it undergoes a vacuum, pressure and vacuum cycle. The wood is then dried a second time.

[0040] Surface cleaning is performed on the treated wood. Next, the treated wood can undergo quality control analysis. The treated wood is then punched, bundled, and packaged for shipment.

[0041] In order to perform the above-described impregnation process, existing conventional southern pine (SYP) wood pressure treatment plants must be modified. Conventional wood pressure treatment plants typically include a wood feed train, a chemical storage system, a water storage system, a treatment chemical mixing tank, a feed product tank, an autoclave for wood impregnation, and a drip pan for product drainage.

[0042] Preferably, conventional equipment used for conventional treatment processes is used for upgrading and modification. Alternatively, conventional equipment may be replaced.

[0043] Large product transfer tanker unloading stations with associated piping are added. New or existing chemical storage tanks are insulated with insulation materials and sheathed with protective materials. Insulation and sheathing are also added to the feed lines between storage tanks and mixing tanks, mixing tanks, and product feed lines to and from work tanks and to and from autoclaves.

[0044] According to one aspect of the present invention, a heating coil is installed in each working tank in order to heat the product. The heating coil is preferably a horizontal coil inserted into the container. Heat tracing of the liquid level indicator is added or upgraded for each of the working tank, mixing tank, autoclave and chemical feed tank. Replacing or adding the heat tracing component is a precautionary measure because the typical liquid level indicator is a magnetic float indicator, which is affected by higher viscosity chemical solutions.

[0045] According to one aspect of the present invention, an updated tote system is installed for adding specialty chemicals to the main mixing tank. A tote is a large plastic container that holds liquids. In operation, a feed line is inserted into the tote and liquid is pumped out of the tote. In addition, a digitally controlled chemical feed system can be installed and used to complete specialty chemical mixing more accurately and efficiently.

[0046] Pumps and filters in conventional plants are also upgraded. The pump circulates the process solution between the storage tank and the process container, and circulates the process solution within the storage tank and the container. The enhanced pump is configured to pump higher viscosity chemical solutions to the working tank. The pump preferably uses a filter bag type filter. According to one aspect of the present invention, the filter medium is a 200 micron filter bag.

[0047] A carbon dioxide storage tank and an associated vaporizer are installed, wherein the feed and return lines lead to the autoclave. In addition, one or more double-plug stop valves with actuators are installed in these two lines.

[0048] According to one aspect of the invention, piping in a conventional plant is rerouted to allow the higher viscosity silicate solution to flow unimpeded. This rerouting may vary depending on the specific design of the existing plant, but should prioritize eliminating flow restrictions that introduce unnecessary turbulence, and being as straight as possible.

[0049] The existing plant piping is preferably kept intact, but the work tank filter and pump system are modified as described above. In addition, all piping is insulated and clad to keep heat loss to a minimum to accommodate operating temperatures of 50°C to 100°C.

[0050] A stirring device is installed in the product working tank. An exemplary agitator is Figure 4 The agitator comprises a motor 1, a gear box 2, sealing components 3, 4, a drive shaft 5 and an impeller 6. As shown in the figure, the impeller is driven clockwise. Figure 5A and Figure 5B The tank with agitator installed is shown. Preferably, the agitator is a large paddle type agitator that provides uniform chemical product mixing. The agitation and pump recirculation system provides a well mixed formulation for the impregnation step.

[0051] To maintain the operating temperature, heating coils are added as well as insulation and blanketing as discussed above. The heating coils maintain the chemical mixture (called product) at a temperature of approximately 50°C to 95°C. While some steps in the impregnation system may use chemicals at room temperature, steps that require heated chemicals are more energy efficient when insulation is provided, providing more consistent process results and reducing product material loss.

[0052] Carbon dioxide gas is used in the process for precipitating chemicals added to wood by lowering the pH. Therefore, a CO2 gas storage, delivery and recovery system is installed. A liquid carbon dioxide storage container is installed, along with the necessary vaporizer. Two-inch ductwork is installed and fed into the rear top area of ​​the autoclave as well as the return vent line.

[0053] According to one aspect of the invention, an upgrade to the plant's programmable logic controller (PLC) system is also installed. The existing PLC control system can be used but must be upgraded with logic changes and the addition of new control loops and appropriate software upgrades. The upgrade is provided, at least in part, in the temperature indication and control system. This upgrade is very important for steady state operation with multiple impregnation cycles. Continuously adding fresh chemicals to the process requires a fast heater response and this logic is provided by the upgraded PLC.

[0054] According to one aspect of the invention, software is added to a programmable logic controller (PLC) system to work in conjunction with digital and mechanical recording devices programmed to track, record and analyze key process variables in real time. Process variables include solution temperature, autoclave pressure, amount of solution utilized, storage tank and process autoclave temperatures, duration of each stage of the process, and correlations between these variables. The data collected can be used to further optimize the process.

[0055] In conventional treatment processes, wood is stacked into "packs" with one layer on top of the other. For the modified plant and process, kiln bars are inserted prior to the treatment process. The kiln bars achieve two goals. First, the kiln bars ensure that the wood is fully impregnated by providing space between the layers. Second, the kiln bars allow the product to be kiln dried to the KD19 standard (kiln dried to 19% moisture content).

[0056] This modified process using kiln bars involves receiving the wood, inserting the kiln bars, bundling the wood bales, performing a one- or two-step impregnation operation, kiln drying the material, unpacking the bales and removing the kiln bars, and preparing the final wood bales for distribution.

[0057] Figure 2 is used for Figure 1 Schematic process layout of a modified wood processing plant for a wood treatment process of FIG. The wood processing plant has a timber receiving section 210, which can be the same as or different from the storage and shipping area 290. The modified 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.

[0058] The first pressure impregnation vessel 220 is coupled to a silicate storage vessel 222 via a mixing tank 224. There is also a vacuum source 226 and a carbon dioxide storage device 228 coupled to the first pressure impregnation vessel 220. A storage and conditioning area 230 is provided for the wood processed in the first pressure impregnation vessel 220.

[0059] The second pressure impregnation vessel 240 is coupled to the silicate storage vessel 242 via a mixing tank 244. There is also a vacuum source 246 and a carbon dioxide storage device 248 coupled to the first pressure impregnation vessel 240. It should be noted that the vacuum source 226 may be the same as the vacuum source 246. Furthermore, the carbon dioxide storage device 228 may be the same as the carbon dioxide storage device 248. Piping may be provided such that only a single vacuum source and / or carbon dioxide storage device is required.

[0060] A storage unit 250 for kiln drying is provided for a kiln 260 in which the processed wood is dried. A tilting crane 270 is used to lift and tilt the wood. A labeling and packaging station 280 is provided as well as a storage area 290 for shipping. As previously mentioned, the storage area 290 may be the same as or different from the forest receiving area 210.

[0061] Figure 6is an overview of the steps used to retrofit and / or update a processing plant. The steps may be performed in any order, but are presented in accordance with one aspect of the invention. At step 110, a heated storage tank for a solution of a siliceous solution is added and / or a heater is added to an existing storage tank. At step 120, a transfer line capable of handling a high ph viscous solution is installed between at least a pre-existing vacuum pressure impregnation tank and the added or existing heated storage tank. At step 130, a CO2 storage tank with an associated vaporizer and CO2 recovery system is added. At step 140, associated lines to and from the pre-existing vacuum pressure impregnation tank and CO2 storage tank and CO2 recovery system are installed. A pump is then installed at step 150 for circulating the solution. Finally, at step 160, a thermal management system is installed, which includes one or more of the following: insulation and blanketing on one or more of the tanks and lines, heat tracing on all level indicators; and heating coils are inserted into the working tank.

[0062] Therefore, although the basic novel features of the present invention as applied to its preferred embodiments have been shown, described and pointed out, it should be understood that various omissions and substitutions and changes may be made to the form and details of the displayed device and the operation of the device by those skilled in the art without departing from the spirit of the present invention. For example, it is clearly intended that all combinations of those elements and / or method steps that perform substantially the same functions in substantially the same manner to achieve the same results are within the scope of the present invention. In addition, it should be recognized that, as a general matter of design choice, the structures and / or elements and / or method steps shown and / or described in conjunction with any disclosed form or embodiment of the present invention may be incorporated in the form of any other disclosed or described or proposed form or embodiment. Therefore, it is intended to be limited only as indicated by the scope of the appended claims.

Claims

1. A method for upgrading a wood vacuum pressure impregnation process plant, the wood vacuum pressure impregnation process plant having a prior vacuum pressure impregnation tank, a feed line, an original vacuum pump and a wood transport system, the method comprising: at least one of adding a heated storage tank for the solution of the siliceous solution and adding a heater to an existing storage tank; installing a transfer line capable of handling high pH viscous solutions between at least the prior vacuum pressure impregnation tank and the added or existing heated storage tank; Installation of CO2 storage tanks with associated vaporizers and CO2 recovery systems; associated piping installed to and from said prior vacuum pressure impregnation tank and said CO2 storage tank and said CO2 recovery system; installing a pump for circulating the solution; as well as Install a thermal management system, which includes: insulation and cladding on one or more of said tanks and lines; Heat tracing on all level indicators; and Insert the heating coil into the working tank.

2. The method for upgrading the wood vacuum pressure impregnation process plant according to claim 1, further comprising: A second vacuum pressure impregnation tank and associated feed line were installed.

3. The method for upgrading the wood vacuum pressure impregnation process plant according to claim 2, further comprising: The prior vacuum pressure impregnation tanks used in the impregnation process for silicate impregnation of wood are upgraded or replaced.

4. The method for upgrading the wood vacuum pressure impregnation process plant according to claim 1, further comprising: Installation of an inline kiln for drying silicate impregnated wood.

5. The method for upgrading the wood vacuum pressure impregnation process plant according to claim 1, further comprising: Installation of an in-line machine stress measurement system for quantification of silicate absorption.

6. The method for upgrading the wood vacuum pressure impregnation process plant according to claim 1, further comprising: Install a hyperspectral analyzer, x-ray analyzer, or acoustic analyzer system for wood morphology analysis.

7. The method for upgrading the wood vacuum pressure impregnation process plant according to claim 1, further comprising: A natural frequency measurement system configured to quantify silicate absorption was installed.

8. The method for upgrading the wood vacuum pressure impregnation process plant according to claim 1, further comprising: A multi-input solution distribution system is installed before the feed line entering the vacuum pressure impregnation tank, wherein the multi-input solution distribution system is configured for formulation control, dosing and delivery of two or more impregnation charges.

9. The method for upgrading the wood vacuum pressure impregnation process plant according to claim 1, further comprising: A delivery system configured to dispense aqueous solutions of high, neutral, and low pH solutions before and after the dipping step is installed.

10. The method for upgrading the wood vacuum pressure impregnation process plant according to claim 1, further comprising: An immersion delivery system configured to dispense aqueous solutions of high, neutral, and low pH solutions before and after the immersion step is installed.

11. The method for upgrading the wood vacuum pressure impregnation process plant as claimed in claim 1, wherein at least one of the solutions is a high pH viscous solution.

12. The method for upgrading the wood 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 for upgrading the wood vacuum pressure impregnation process plant according to claim 1, further comprising: An autoclave configured to process the siliceous solution pressurized to at least 190 psi is installed.

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

15. A plant for performing a vacuum pressure impregnation process for wood, the plant comprising: A wood handling apparatus configured to transport wood from a receiving area to a plurality of stations, wherein the stations include: a first vacuum pressure impregnation tank coupled to a first heated storage tank, a first mixing tank, a first vacuum source, and a transfer line configured to process 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 vessel coupled to a second heated storage tank, a second mixing tank, a second vacuum source, and a transfer line configured to process a high pH viscous solution between at least the first vacuum pressure impregnation tank and the heated storage tank; at least one CO2 storage tank with an associated vaporizer and a CO2 recovery system coupled to at least the first vacuum pressure impregnation vessel and the second vacuum pressure impregnation vessel; at least one kiln; At least the labeling station; at least one packaging station; and At least at the shipping station; A thermal management system comprising: Insulation and cladding on one or more of said vessels, tanks and pipelines; and Heat tracing sensors; and A pump is configured to circulate the solution.

16. The plant for performing the vacuum pressure impregnation process for wood according to claim 15, further comprising: An autoclave configured to process a siliceous solution pressurized to at least 190 psi.

17. The plant for performing a wood vacuum pressure impregnation process according to claim 15, further comprising: A controller configured to track, record and analyze process variables of the sodium silicate solution, wherein the process variables include one or more of the following: solution temperature, autoclave pressure, amount of solution utilized, storage tank temperature, process autoclave temperature, and duration of each stage of the process.

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

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