CN104385406A - Deep degreasing method for timber through vacuum heat treatment - Google Patents
Deep degreasing method for timber through vacuum heat treatment Download PDFInfo
- Publication number
- CN104385406A CN104385406A CN201410513828.7A CN201410513828A CN104385406A CN 104385406 A CN104385406 A CN 104385406A CN 201410513828 A CN201410513828 A CN 201410513828A CN 104385406 A CN104385406 A CN 104385406A
- Authority
- CN
- China
- Prior art keywords
- degreasing
- timber
- wood
- temperature
- tank
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
- B27K5/00—Treating of wood not provided for in groups B27K1/00, B27K3/00
Abstract
A provided deep degreasing method for timber through vacuum heat treatment comprises: selecting wood with certain thickness, piling wood in an enclosed degreasing tank; heating wood to enable wood to have a drying temperature of 40 DEG C-60 DEG C, then reducing the air pressure to a first vacuum degree, so as to adjust the water content of wood to be 5%-12%; continuing to reduce the air pressure to a second vacuum degree, and also raising the temperature to a preheating temperature, so as to dry wood to be absolutely dry; and keeping the second vacuum degree, continuing to raise the temperature to a degreasing temperature, and staying for a preset degreasing period, so as to perform deep degreasing processing on wood. The wood degreasing method increases the degreasing depth on wood, improves the wood degreasing efficiency of a conventional degreasing method, and also improves the wood dimension stability without causing substantial color variation.
Description
Technical field
The present invention relates to a kind of wood vacuum heat treatment degree of depth degreasing method, namely lower than under atmospheric pressure conditions, high-temperature process is being carried out to timber, this degreasing method adds the degreasing depth of timber, improve the timber degreasing efficiency of existing degreasing method, improve the dimensional stability of timber, color change is not remarkable simultaneously.
Background technology
Have normal resin canal in the wood structure of coniferous wood Pinaceae Pinus, Picea, Larch, Pseudotsuga, silver-colored araucaria and Keteleeria, it secretes resin, and resin content enriches.In timber processing and utilization process, the follow-up sawing of high-load resin interference timber, sanding, the operation such as paint and splicing, and it is higher once environment temperature, resin can ooze to wood surface, pollute timber-work, therefore, such timber needs to carry out ungrease treatment in processing and utilization process, and then improve its processing characteristics and surface quality, expand its range of application.
At present, existing timber defatting technology mainly contains three classes: the first kind is chemical method, as alkali lye saponification method, solution extraction; Equations of The Second Kind is physical method, as gas steams high temperature drying techniques; 3rd class is integrated conduct method, as chemical method and drying means carry out simultaneously.
Due to the diversity of timber kind, result in the otherness of wood characteristics, particularly poor for some wood permeabilities, the characteristic that medicament dipping is difficult, as larch, masson pine etc., is difficult to adopt chemical agent to carry out ungrease treatment effectively.Therefore, with regard to this kind of timber, still have problems in improvement its degreasing rate, degreasing depth etc.; And in liquid ungrease treatment industrial processes, can produce a large amount of pollutant effluents, also need recycling to liquid, expense cost is higher.In the degreasing of timberphysics method, CN101633189A patent discloses a kind of degreasing pinewoods method, hot press twice hot pressing pine is adopted to carry out degreasing, the method defines the thickness of process Pine Samples, the degree of depth degreasing of timber cannot be realized, in the ungrease treatment in enormous quantities of pine square bar, there is certain limitation.The patent of CN103791694A discloses a kind of pine dries and degreasing method, and adopt Steam Heating drying kiln, to temperature 70 ~ 75 DEG C, keep 150 ~ 200 hours, this PROCESS FOR TREATMENT is consuming time relatively long, reduces production efficiency.In wood comprehensive process degreasing, CN1204569A patent discloses a kind of pinewood degreasing modification method and apparatus, adopts liquid process and steam drying process two kinds of methods, still there is the defect of existing liquid chemical degreasing method.Simultaneously, the method can not be carried out due to degreasing and drying simultaneously, timber is in degreasing tank after degreasing, need again to be moved in dry kiln and carry out drying, and in steam drying process, need steam generator, so, this process equipment cost and human cost higher, reduce the efficiency of timber ungrease treatment.
The present invention is intended to improve the defect existing for existing timber defatting technology, carries out degree of depth ungrease treatment, improve the dimensional stability of timber simultaneously to pine class timber.The present invention also take into account reduction production cost, reduces energy resource consumption, avoids chemical contamination, the aspects such as protection of the environment, the requirement that response national energy-saving reduces discharging, for industrial applications provides a kind of feasible technical scheme.
Summary of the invention
Technical problem to be solved by this invention is the deficiency overcoming the existence of existing timber defatting technology, there is provided a kind of wood vacuum heat treatment degree of depth degreasing method, this degreasing method has that degreasing depth is large, treatment effeciency is high, degreasing equipment is simple, production cost is low, energy loss is few, human cost is low and the advantage of environmental protection.Apply all right deep removal pine class wood internal rosin of degreasing method of the present invention, improve the dimensional stability of the rear timber of process, color change is not remarkable simultaneously.
The invention provides a kind of wood vacuum heat treatment degree of depth degreasing method, comprising: choose certain thickness timber, log yard is put into airtight degreasing tank; Timber is heated, makes timber reach the baking temperature of 40 DEG C ~ 60 DEG C, then, reduce air pressure to the first vacuum condition in degreasing tank, keep described baking temperature and described first vacuum condition, moisture content to 5% ~ 12% of adjustment timber; Continue to reduce air pressure to the second vacuum condition in described degreasing tank, improve temperature in described degreasing tank to pre-heating temperature simultaneously, make the drying of wood to over dry; Keep described second vacuum condition, the temperature in the described degreasing tank of continuation raising is to skimming temp, and the degreasing time through presetting, degree of depth ungrease treatment is carried out to timber.
Specifically, this degreasing method can be further refined as following step:
Step one: choose timber, is processed into and has certain thickness sheet material, and seasoning piling puts into degreasing tank routinely, closes tank door;
Step 2: open heater and convection device, timber is heated, the temperature of timber is made to reach 40 DEG C ~ 60 DEG C, recycling vacuum extractor vacuumizes degreasing tank, vacuum in degreasing tank is made to reach between-0.04MPa ~-0.06MPa, keep temperature and vacuum condition in tank, desiccated wood to moisture content is 5% ~ 12%;
Step 3: slowly heat the timber in degreasing tank, makes temperature reach the pre-heating temperature of 100 DEG C ~ 130 DEG C.This step is vacuumized by batch (-type) simultaneously and keeps vacuum in degreasing tank between-0.06MPa ~-0.09MPa, and desiccated wood is to over dry;
Step 4: continue the skimming temp being warming up to 180 DEG C ~ 240 DEG C, in maintenance tank body, vacuum is between-0.06MPa ~-0.09MPa, and carry out ungrease treatment to timber, the processing time is 4 hours ~ 12 hours;
Step 5: after above-mentioned ungrease treatment terminates, carries out cooling conditioning, cools the temperature to 80 DEG C ~ 90 DEG C, and the final moisture content of adjustment timber is 6% ~ 12%;
Step 6: Wood temperature is down to room temperature, takes out timber in degreasing tank.
Timber after the ungrease treatment of above-mentioned steps, significantly promote in degreasing depth and degreasing rate etc., and in degreasing tank, complete timber degreasing and dry two kinds of process simultaneously, reduce the problem such as carrying and gas discharging in processing procedure, improve degreasing efficiency, meet the requirement of energy-conserving and environment-protective.
The present invention also provides a kind of degreasing equipment applying above-mentioned degreasing method, comprising: degreasing tank, and the space of the accommodation timber that formation one is airtight, carries out ungrease treatment to timber; Vacuum extractor, under making degreasing tank be in vacuum condition; Heater, is arranged in degreasing tank, heats timber; Checkout gear, detects the temperature and humidity of timber in degreasing tank in real time.
Be different from existing degreasing equipment, degreasing equipment of the present invention can be applicable to the degreasing method of above-mentioned timber, can simultaneously by the degree of depth degreasing of timber and drying integrated, decrease the complexity of equipment, cost-saving, meet high speed produce requirement.
Detailed description of the invention
For making the object, technical solutions and advantages of the present invention clearly understand, below in conjunction with embodiment, the present invention is described in further details.At this, exemplary embodiment of the present invention and illustrating for explaining the present invention, but not as a limitation of the invention.
The degreasing equipment adopted in following examples is made up of degreasing tank, vacuum extractor, heater and checkout gear four parts.Degreasing tank, the space of the accommodation timber that formation one is airtight, carries out ungrease treatment to timber; Vacuum extractor, under making degreasing tank be in vacuum condition; Heater, is arranged in degreasing tank, heats timber; Checkout gear, detects the temperature and humidity of timber in degreasing tank in real time.Wherein, vacuum extractor adopts vavuum pump to vacuumize degreasing tank, and vacuum meter measurement category is 0MPa ~-0.1MPa; Heater is electrical heating, heating temperature range RT+10 DEG C ~ 350 DEG C; Checkout gear is thermocouple, temperature polling instrument and temperature acquisition recorder, namely by wood internal temperature in thermocouple measurement skimming processes, and temperature acquisition recorder record temperature.
Timber after ungrease treatment is carried out to a series of measurements such as degreasing rate, weight-loss ratio, dimensional stability and color, evaluate timber degreasing rate and performance change thereof.Leading indicator degreasing rate assay method of the present invention is: measure untreated material and degreasing material ether extraction thing, i.e. fat content according to GB/T 2677.6-94 " mensuration of paper making raw material organic solvent extract content ", then calculate degreasing rate, formula is as follows:
（1）
In formula, X
1for processing the fat content (%) of front sample; X
2for processing the fat content (%) of rear sample.
Timber weight-loss ratio, with reference to GB/T 13942.1-92 " timber natural Durability Test method Natural Resistance of Wood To Microbial Deterioration laboratory test methods ", calculates timber weight-loss ratio formula as follows:
（2）
In formula, W
1for processing the oven dry weight of front sample; W
2for processing the oven dry weight of rear sample.
Wood dimensional stability drying shrinkage and bulking measure according to GB/T 1932-2009 " Method for determination of the shrinkage of wood " and GB/T 1934.2-2009 " Method for determination of the swelling of wood ".
Wood color adopts CIE(1976) L*a*b* system determines: Δ L* is luminosity equation, and become clear than control sample on the occasion of expression, negative value represents darker than control sample; Δ a* is the changing value of a*, is more partial to redness on the occasion of larger expression color, and the larger expression color of negative value is more partial to green; Δ b* is the changing value of b*, is more partial to yellow on the occasion of larger expression color, and the larger expression color of negative value is more partial to blueness; Δ C* is color saturation difference, and distincter than control sample on the occasion of expression, negative value represents deeply darker than control sample; Δ E* is overall aberration, numerical value larger expression measured object and control sample color distinction larger; Δ H* is hue difference, and the larger expression measured object of numerical value and the change of control sample form and aspect are greatly.By above numerical evaluation, analyze wood color change before and after ungrease treatment.
Embodiment 1.
Choose larchwood, be processed into thickness 60mm sheet material, piling puts into degreasing tank, closes tank door; Open heater, be heated to Wood temperature and reach 60 DEG C, this process adopts and measures wood internal diverse location temperature as the thermocouple of one of checkout gear, and with temperature acquisition recorder, record is carried out to temperature data, afterwards, degreasing tank is vacuumized and reduces tank internal gas pressure, make its vacuum reach first vacuum condition of-0.04MPa ~-0.06MPa, keep temperature and the first vacuum condition in tank, desiccated wood to moisture content is 8%; Slowly heat timber in tank body, reach the pre-heating temperature of 120 DEG C, meanwhile, adopt the mode that vacuumizes of batch (-type) to keep second vacuum condition of vacuum between-0.06MPa ~-0.09MPa in tank body in this process, desiccated wood is to over dry; Continue to be warming up to skimming temp 220 DEG C, keep second vacuum condition of vacuum between-0.06MPa ~-0.09MPa in tank body, degreasing time is 10 hours; After ungrease treatment terminates, carry out cooling conditioning, temperature is down to 80 DEG C, and the final moisture content of timber is transferred to 12%; Wood temperature is down to room temperature naturally, takes out in tank.
Larchwood is through this degreasing process process, and degreasing rate can reach 88%, and can realize effective degree of depth degreasing on sheet material integral thickness direction; After degreasing, larchwood weight-loss ratio is 7.4%; The dimensional stability of degreasing material is improved, and gas dry volume contract with dry rate is 5.67%, volume bulking factor 6.15% after gas is dry, compared with non-degreasing material, reduces by 43.0% and 39.7% respectively.After ungrease treatment, larchwood color slightly deepens, and concrete measured value is as shown in table 1.
Embodiment 2.
Choose larchwood, be processed into thickness 30mm sheet material, piling puts into degreasing tank, closes tank door; Open heater, be heated to Wood temperature and reach 50 DEG C, this process adopts and measures wood internal diverse location temperature as the thermocouple of one of checkout gear, and with temperature acquisition recorder, record is carried out to temperature data, afterwards, degreasing tank is vacuumized and reduces tank internal gas pressure, make its vacuum reach first vacuum condition of-0.04MPa ~-0.06MPa, keep temperature and the first vacuum condition in tank, desiccated wood to moisture content is 8%; Slowly heat timber in tank body, reach the pre-heating temperature of 120 DEG C, meanwhile, adopt the mode that vacuumizes of batch (-type) to keep second vacuum condition of vacuum between-0.06MPa ~-0.09MPa in tank body in this process, desiccated wood is to over dry; Continue to be warming up to skimming temp 200 DEG C, keep second vacuum condition of vacuum between-0.06MPa ~-0.09MPa in tank body, degreasing time is 10 hours; After ungrease treatment terminates, carry out cooling conditioning, temperature is down to 80 DEG C, and the final moisture content of timber is transferred to 12%; Wood temperature is down to room temperature naturally, takes out in tank.
Larchwood is through this degreasing process process, and degreasing rate can reach 90%, and can realize effective degree of depth degreasing on sheet material integral thickness direction; After degreasing, larchwood weight-loss ratio is 3.4%; The dimensional stability of degreasing material is improved, and gas dry volume contract with dry rate is 6.02%, volume bulking factor 6.51% after gas is dry, compared with non-degreasing material, reduces by 39.5% and 36.2% respectively.After ungrease treatment, the change of larchwood color is not obvious, and concrete measured value is as shown in table 1.
Embodiment 3.
Choose larchwood, be processed into thickness 10mm sheet material, piling puts into degreasing tank, closes tank door; Open heater, be heated to Wood temperature and reach 40 DEG C, this process adopts and measures wood internal diverse location temperature as the thermocouple of one of checkout gear, and with temperature acquisition recorder, record is carried out to temperature data, afterwards, degreasing tank is vacuumized and reduces tank internal gas pressure, make its vacuum reach first vacuum condition of-0.04MPa ~-0.06MPa, keep temperature and the first vacuum condition in tank, desiccated wood to moisture content is 8%; Slowly heat timber in tank body, reach the pre-heating temperature of 120 DEG C, meanwhile, adopt the mode that vacuumizes of batch (-type) to keep second vacuum condition of vacuum between-0.06MPa ~-0.09MPa in tank body in this process, desiccated wood is to over dry; Continue to be warming up to skimming temp 180 DEG C, keep second vacuum condition of vacuum between-0.06MPa ~-0.09MPa in tank body, degreasing time is 8 hours; After ungrease treatment terminates, carry out cooling conditioning, temperature is down to 80 DEG C, and the final moisture content of timber is transferred to 12%; Wood temperature is down to room temperature naturally, takes out in tank.
Larchwood is through this degreasing process process, and degreasing rate can reach 93%, and can realize effective degree of depth degreasing on sheet material integral thickness direction; After degreasing, larchwood weight-loss ratio is 2.8%; The dimensional stability of degreasing material is improved, and gas dry volume contract with dry rate is 7.25%, volume bulking factor 8.02% after gas is dry, compared with non-degreasing material, reduces by 27.1% and 21.4% respectively.After ungrease treatment, the change of larchwood color is not obvious, and concrete measured value is as shown in table 1.
The larchwood color change of table 1 different degreasing process condition ungrease treatment.
Above-mentioned three embodiments just schematically illustrate degreasing method of the present invention, and parameter wherein is also just chosen to implement degreasing method of the present invention.In fact, the setting of the design parameter in degreasing method of the present invention is not limited to above-mentioned three embodiments.
Specifically, the setting of parameter can be selected from following numerical value.Wherein, the thickness of timber is below 60mm, baking temperature is 40 DEG C ~ 60 DEG C, first vacuum condition is the scope of-0.04MPa ~-0.06MPa, second vacuum condition is the scope of-0.06MPa ~-0.09MPa, pre-heating temperature is 100 DEG C ~ 130 DEG C, and skimming temp is 160 DEG C ~ 240 DEG C, and the degreasing time preset is 4 hours ~ 12 hours.
Above-described detailed description of the invention; object of the present invention, technical scheme and beneficial effect are further described; be understood that; the foregoing is only the specific embodiment of the present invention; the protection domain be not intended to limit the present invention; within the spirit and principles in the present invention all, any amendment made, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (7)
1. a wood vacuum heat treatment degree of depth degreasing method, is characterized in that, comprising:
Choose certain thickness timber, log yard is put into airtight degreasing tank;
Timber is heated, makes timber reach the baking temperature of 40 DEG C ~ 60 DEG C, then, reduce air pressure to the first vacuum condition in degreasing tank, keep described baking temperature and described first vacuum condition, moisture content to 5% ~ 12% of adjustment timber;
Continue to reduce air pressure to the second vacuum condition in described degreasing tank, improve temperature in described degreasing tank to pre-heating temperature simultaneously, make the drying of wood to over dry;
Keep described second vacuum condition, the temperature in the described degreasing tank of continuation raising is to skimming temp, and the degreasing time through presetting, degree of depth ungrease treatment is carried out to timber.
2. degreasing method according to claim 1, is characterized in that, also comprises:
After described degreasing time, in described degreasing tank, be filled with steam, the temperature in described degreasing tank be reduced to 80 DEG C ~ 90 DEG C, adjust moisture content to 6% ~ 10% of timber simultaneously;
And the temperature of timber is down to room temperature, in described degreasing tank, take out the timber after degree of depth ungrease treatment.
3. according to the degreasing method of claim 1 or 2, wherein,
Described first vacuum condition is-0.04MPa ~-0.06MPa;
Described second vacuum condition is-0.06MPa ~-0.09MPa.
4. according to the degreasing method of claim 1 or 2, wherein,
Described pre-heating temperature is 100 DEG C ~ 130 DEG C;
Described skimming temp is 160 DEG C ~ 240 DEG C.
5. the degreasing time preset according to the degreasing method of claim 1 or 2, wherein, is 4 hours ~ 12 hours.
6. according to the degreasing method of claim 1 or 2, wherein, described certain thickness is below 60mm.
7. application rights requires a degreasing equipment for the degreasing method of 1-6, it is characterized in that, comprising:
Degreasing tank, the space of the accommodation timber that formation one is airtight, carries out ungrease treatment to timber;
Vacuum extractor, under making described degreasing tank be in different vacuum conditions;
Heater, is arranged in described degreasing tank, heats timber;
Checkout gear, detects the temperature and humidity of timber in described degreasing tank in real time.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410513828.7A CN104385406B (en) | 2014-09-30 | 2014-09-30 | A kind of wood vacuum heat treatment degree of depth degreasing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410513828.7A CN104385406B (en) | 2014-09-30 | 2014-09-30 | A kind of wood vacuum heat treatment degree of depth degreasing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104385406A true CN104385406A (en) | 2015-03-04 |
| CN104385406B CN104385406B (en) | 2016-04-27 |
Family
ID=52603408
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410513828.7A Active CN104385406B (en) | 2014-09-30 | 2014-09-30 | A kind of wood vacuum heat treatment degree of depth degreasing method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104385406B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105171866A (en) * | 2015-06-11 | 2015-12-23 | 中国林业科学研究院木材工业研究所 | Method for modifying wood through combination of resin impregnation reinforcing, vacuum drying and heat treatment |
| CN107225639A (en) * | 2017-06-02 | 2017-10-03 | 安徽宏润工艺品有限公司 | A kind of mildrew resistant finish method of wooden boards |
| CN112025886A (en) * | 2020-08-22 | 2020-12-04 | 黄志林 | Method for manufacturing wood for outdoor garden |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101439529A (en) * | 2008-12-23 | 2009-05-27 | 罗玉成 | Microwave vacuum drying and carbonizing device and method for wood |
| CN103286834A (en) * | 2013-07-02 | 2013-09-11 | 陈军 | Integrated process for degreasing, deoiling and drying woods |
| CN103538132A (en) * | 2013-09-25 | 2014-01-29 | 开原圣意达木材干燥设备有限公司 | Method for directly carbonizing wet timber |
| CN103542696A (en) * | 2013-09-25 | 2014-01-29 | 开原圣意达木材干燥设备有限公司 | Wood vacuum drying-carbonization integrated kiln |
-
2014
- 2014-09-30 CN CN201410513828.7A patent/CN104385406B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101439529A (en) * | 2008-12-23 | 2009-05-27 | 罗玉成 | Microwave vacuum drying and carbonizing device and method for wood |
| CN103286834A (en) * | 2013-07-02 | 2013-09-11 | 陈军 | Integrated process for degreasing, deoiling and drying woods |
| CN103538132A (en) * | 2013-09-25 | 2014-01-29 | 开原圣意达木材干燥设备有限公司 | Method for directly carbonizing wet timber |
| CN103542696A (en) * | 2013-09-25 | 2014-01-29 | 开原圣意达木材干燥设备有限公司 | Wood vacuum drying-carbonization integrated kiln |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105171866A (en) * | 2015-06-11 | 2015-12-23 | 中国林业科学研究院木材工业研究所 | Method for modifying wood through combination of resin impregnation reinforcing, vacuum drying and heat treatment |
| CN107225639A (en) * | 2017-06-02 | 2017-10-03 | 安徽宏润工艺品有限公司 | A kind of mildrew resistant finish method of wooden boards |
| CN112025886A (en) * | 2020-08-22 | 2020-12-04 | 黄志林 | Method for manufacturing wood for outdoor garden |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104385406B (en) | 2016-04-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104385406B (en) | A kind of wood vacuum heat treatment degree of depth degreasing method | |
| CN105783427A (en) | Microwave vacuum drying method achieving staging control | |
| CN103538132B (en) | Method for directly carbonizing wet timber | |
| CN103542696B (en) | A kind of vacuum drying of wood carbonization one kiln | |
| WO2011077390A3 (en) | Method for monitoring primary drying of a freeze-drying process | |
| CN204196441U (en) | A kind of decorating film stamp drying unit | |
| CN203518434U (en) | High-frequency vacuum timber drying device | |
| CN101424600A (en) | Method for making high smectite sandstone casting slice | |
| CN101474813A (en) | High-efficient method for removing pine resin | |
| CN202760152U (en) | Device used for controlling oxygen content in drying tobacco shreds in rotary cylinder | |
| TW201605351A (en) | All weather tea processes by using s (conductivity, unit is Siemens) and enclosed hydrodynamic system with related equipment | |
| CN207066049U (en) | A kind of novel energy-conserving tea drier | |
| CN102550950A (en) | Method and device for producing dry-steamed fine dried noodles | |
| CN107244920A (en) | Carborundum injection forming sintering method | |
| CN203353586U (en) | Black tea fermentation apparatus with oxygen supply function | |
| CN103981738A (en) | Wool fabric printing technology | |
| CN101164745B (en) | Method for manufacturing plate by carbonizing bamboo | |
| CN110219205A (en) | A kind of heat-resisting base paper for excursion press mark and preparation method thereof | |
| KR20150040541A (en) | Heating and drying method of veneer using microwave | |
| CN103760058A (en) | Method for determining fat by acid hydrolysis | |
| CN113008721A (en) | Rehmannia root moistening stop condition analysis method based on water content change | |
| CN102962183B (en) | Organic silicon product surface oil-seal method | |
| CN204772872U (en) | Hot system of processing of solid board | |
| CN203928618U (en) | A kind of Novel heated air circulation case | |
| CN104647492B (en) | The hot-working sterilization de-watering apparatus of solid wood board |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |