CN110357676A - The method for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method - Google Patents
The method for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method Download PDFInfo
- Publication number
- CN110357676A CN110357676A CN201910462615.9A CN201910462615A CN110357676A CN 110357676 A CN110357676 A CN 110357676A CN 201910462615 A CN201910462615 A CN 201910462615A CN 110357676 A CN110357676 A CN 110357676A
- Authority
- CN
- China
- Prior art keywords
- guanite
- model
- nitrogen phosphorus
- molar ratio
- technological parameter
- 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.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05F—ORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C, e.g. FERTILISERS FROM WASTE OR REFUSE
- C05F3/00—Fertilisers from human or animal excrements, e.g. manure
- C05F3/02—Guano
-
- G—PHYSICS
- G16—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR SPECIFIC APPLICATION FIELDS
- G16C—COMPUTATIONAL CHEMISTRY; CHEMOINFORMATICS; COMPUTATIONAL MATERIALS SCIENCE
- G16C20/00—Chemoinformatics, i.e. ICT specially adapted for the handling of physicochemical or structural data of chemical particles, elements, compounds or mixtures
- G16C20/10—Analysis or design of chemical reactions, syntheses or processes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A40/00—Adaptation technologies in agriculture, forestry, livestock or agroalimentary production
- Y02A40/10—Adaptation technologies in agriculture, forestry, livestock or agroalimentary production in agriculture
- Y02A40/20—Fertilizers of biological origin, e.g. guano or fertilizers made from animal corpses
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Analytical Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Crystallography & Structural Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Bioinformatics & Computational Biology (AREA)
- Computing Systems (AREA)
- Theoretical Computer Science (AREA)
- Processing Of Solid Wastes (AREA)
Abstract
The invention discloses the methods for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method: (1) choosing four significant variables for influencing guanite method recycling nitrogen phosphorus efficiency and guanite purity；(2) Surface Method design guanite method recycling nitrogen phosphorus RSM batch experiment according to response；(3) the RSM batch experiment of guanite method recycling nitrogen phosphorus is carried out, response needed for model is established in acquisition；(4) multiple regression fitting is carried out to experimental data using Design-Expert software, establishes secondary multivariate regression models；(5) ANOVA analysis and significance test are carried out to response surface design secondary model, does verification test testing model；(6) it is arbitrarily designated model internal variable numerical value, experimental verification is carried out to each response；(7) according to process goal, optimal processing parameter is determined using Design-Expert software.The present invention solves the problems, such as that technological parameter can not determine when handling different waste water in Practical Project.
Description
Technical field
The present invention relates to the methods for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method
Background technique
Ammonium magnesium phosphate is commonly called as guanite, chemical formula MgNH4PO46H2O, the entitled struvite of English, abbreviation
MAP, relative molecular mass 245.41, specific gravity 1.7.Phosphorus content in guanite is up to 51.8% (with P2O5Meter), than natural
Existing high-grade rock phosphate in powder phosphorus content (46%) also height, inherently a kind of valuable rich rock phosphate in powder contain nitrogen simultaneously
Nutrient needed for the plant growths such as phosphorus, solvable, slightly soluble under neutrallty condition, alkaline item under guanite acid condition in aqueous solution
Indissoluble under part, so that guanite becomes one kind and can be avoided the excellent slow-release fertilizer of " burn seedlings ", so that the recycling of guanite has
It has an economic benefit.
There are mainly three types of structure crystal ionics for guanite reaction: NH4 +, Mg2+, PO4 3-/HPO4 2-。Ca2+Meeting and Mg2+Competition, it is raw
At synthos, the purity of struvite production is influenced.PH influences the saturation coefficient of ammonium magnesium phosphate, and magnesium ammonium phosphate sediment is precipitated.
Suitable N/P, Mg/P, Mg/Ca, recovery of nitrogen and phosphorus rate of the equimolar than being conducive to improve guanite technique with pH, it is pure to improve product
Degree rationally controls dosage, and then improves the process efficiency of guanite.
The qualitative analysis for predominantly staying in conventional single-factor influence for the research of guanite technique at present, in actual process
In, the water quality of different waste water is different, can not carry out quantitative analysis to the interaction between multifactor, determine that optimised process is joined
Number.Ammonia nitrogen in waste water as landfill leachate and rare-earth smelting generate is dense, can recycle nitrogen with guanite method, but most
Excellent pH and the more difficult determination of dosage；Pig farm biogas slurry, N relative amount is higher, and pH is relatively suitble to guanite reaction, anaerobic sludge digestion
Up to 100mg/L or more, without adding phosphorus source guanite reaction can occur for phosphorus element content in liquid, in grain fermentation waste water
Ammonia nitrogen and content of inorganic phosphorus ratio are moderate, but Ca2+ content is higher, and influence factor is more when recycling nitrogen phosphorus using guanite method.
Response Surface Method (Response Surface Methodology, RSM) is a kind of multiple regression fitting modeling side
Method is able to carry out multifactor impact analysis, prediction result.It is the common experimental design of recent domestic and optimization method.
Box-Behnken Design is common experimental design method in RSM.This method has experiment number few, and precision is high, in advance
The advantages that survey performance is good, avoids extreme experimental conditions.Design Expert be a Response Surface Method design and modeling it is soft
Part can be convenient quickly contrived experiment scheme using the software, establish model according to experimental data, verify model conspicuousness with
And different condition optimized parameter is calculated, meet various technique requirements.
Summary of the invention
Optimal procedure parameters are doubt when to solve the problems, such as in guanite technique to different waste water qualities, and the present invention provides
It is quickly determined in the processing of different waste water based on the method that Response Surface Method determines guanite recycling nitrogen phosphorus technological parameter
The parameter of guanite recycling nitrogen phosphorus technique.
In order to achieve the above objectives, the technical solution used in the present invention are as follows:
Step 1: being based on guanite reaction principle, and choosing pH, N/P molar ratio, Mg/P molar ratio, Mg/Ca molar ratio is shadow
Ring four significant variables that guanite generates；Choose three important indicators of guanite technique: nitrogen removal efficiency, tp removal rate, bird
Response of the coprolite purity as model；
Step 2: Design- is used according to Box-Behnken method according to the correlation between dependent variable and independent variable
Expert software design experimental program.
Step 3: building guanite reaction experiment device, is tested according to the combination of the variable of testing program, measures and count
Calculate N removal rate, P removal rate, three responses of guanite purity；
Step 4: the response data preparation analysis fitting using Design-Expert software to being obtained in step 3, sieve
Significant variable is selected, is established using pH, N/P molar ratio, Mg/P molar ratio, Mg/Ca molar ratio as the secondary multiple regression mould of independent variable
Type:
In formula: YiFor dependent variable response, β0For constant term, βiFor linear coefficient, βiiFor interaction term coefficient, βijIt is secondary
Term coefficient, XiFor independent variable；
Step 5: carrying out F inspection to each regression equation coefficient and equation model and P examined, obtain ANOVA analysis result and
Significance test result；If R-Squared (coefficient of determination) > 0.98, Adj R-Squared (the correction coefficient of determination) > 0.95,
Pred R-Squared (the prediction coefficient of determination) > 0.92, Adj R-Squared-Pred R-Squared > 0.2, Model (mould
Type)-significant, Lack of fit (losing analog values)-significant, then forecast result of model is good.
Step 6: being arbitrarily designated independent variable numerical value in model scope, carries out experimental verification to model；
Step 7: method is determined to the optimal procedure parameters；Using Design Expert software, with guanite purity,
N removal rate, P removal rate are target value, and different different degrees are arranged according to process goal, and each influence factor adjustable range and most is arranged
Lower bound degree calculates the optimal processing parameter of guanite reaction by Optimization；
It is that 1~4, Mg/P molar ratio is adjusted that pH adjustable range, which is 8~10, N/P molar ratio adjustable range, in the step 1
Range is that 0.8~1.6, Mg/Ca molar ratio adjustable range is 0.8~3.2；
In the step 3 reaction time be 60min, stand still for crystals the time be 60min, mixing speed be 160~
250rpm, adjusting medicament used in pH is NaOH solution.
The second-order response curved surface expression formula of the step 4 kind tp removal rate are as follows:
Rp=-422.31+96.01A+19.98B+93.19C-26.61D-1.58AB-4.70AC+1.78AD- 2.60BC+
0.94BD+5.24CD-4.64A2-0.58B2-19.17C2
RN=-634.46+133.31A-8.69B+96.07C-0.51D-9.56AC+3.18AD+4.25BC-4 .06BD+
5.06CD-6.83A2+1.05B2-16.15C2-2.84D2
ωpurity=-670.63+148.41A+24.04B-59.06C+92.68D-4.04AD+17.31CD-8.30A2-
3.65B2-12.03D2
Wherein: Rp--- tp removal rate, %
RN--- nitrogen removal efficiency, %
ωpurity--- guanite purity, %
A——pH
B --- N/P molar ratio
C --- Mg/P molar ratio
D --- Mg/Ca molar ratio
The invention has the following advantages:
(1) present invention chooses on the basis of experiment of single factor reacts pH, N/P molar ratio being affected, Mg/ to guanite
P molar ratio, Mg/Ca molar ratio are investigated, pure by nitrogen removal efficiency, tp removal rate and guanite of the Response Surface Method to reaction
Degree constructs polynary quadratic equation.By the Optimization in Design Expert software, quickly calculated using this model,
Obtain the optimal processing parameter under the conditions of different waste water qualities.
(2) modeling process of the present invention is easy to operate, and without carrying out complicated mathematical operation, can establish has good prediction
The model of ability.
(3) present invention can be combined with on-line monitoring system and automatic control system, be adjusted in time according to real-time influent quality
Whole relevant parameter, guarantee reach default treatment effect, to make it possible that guanite method recycles the Automatic Control of nitrogen phosphorus.
(4) present invention can calculate optimal solution for different process goals, balance the relationship between cost and efficiency, fit
Answer different working conditions and productive target.
Detailed description of the invention
Fig. 1 method flow diagram
Specific embodiment
Idea of the invention is that guanite response prediction model is established by the Box-Behnke method in Response Surface Method,
The method for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method is provided, provides guidance for actual production.
The method for determining guanite recycling nitrogen phosphorus technique optimal processing parameter is analyzed using response surface design, including is walked as follows
It is rapid:
Step 1: being based on guanite reaction principle, and choosing pH, N/P molar ratio, Mg/P molar ratio, Mg/Ca molar ratio is shadow
Ring four significant variables that guanite generates；Choose three important indicators of guanite technique: N removal rate, P removal rate, birds droppings
Response of the stone purity as model；
Step 2: in view of the correlation between dependent variable and independent variable, the Box- in Surface Method according to response
Behnken method obtains experimental program using Design-Expert software, and experimental program such as following table indicates:
1 Box-Behnke testing program of table
Step 3: building guanite reaction experiment device, is tested according to the combination of the variable of testing program, the reaction time
For 60min, standing still for crystals the time is 60min, and mixing speed is 160~250rpm；Reaction solution pH is monitored using pH meter, uses salt
Acid and sodium hydroxide solution maintain reaction solution pH；Using in salicylic acid-sodium hypochlorite spectrophotometry measurement reaction front and back solution
Ammonia nitrogen concentration, use molybdenum-antimony anti-spectrophotometric method measurement reaction front and back solution in orthophosphoric acid root concentration, calculate N removal rate, P
Removal rate；Ammonia nitrogen concentration in lysate, calculates the content of ammonium magnesium phosphate, and then produced after being dissolved again by analysis sediment
The calculation formula of the purity of object, purity is as follows:
In formula:
ω --- guanite purity, %
C --- the ammonia nitrogen concentration in precipitating lysate, mg/L
A --- the extension rate of precipitating lysate
V --- the volume of precipitating lysate, L
The precipitating quality of m --- dissolution, g
245.41 --- struvite crystals relative molecular mass
14.007 --- nitrogen relative atomic mass.
Step 4: the response data preparation obtained in step 3 is analyzed using Design-Expert software, is used
AlCc method filters out significant variable, obtain be with pH, N/P molar ratio, Mg/P molar ratio, Mg/Ca molar ratio estimate one's own ability it is secondary
Multivariate regression models:
Rp=-422.31+96.01A+19.98B+93.19C-26.61D-1.58AB-4.70AC+1.78AD- 2.60BC+
0.94BD+5.24CD-4.64A2-0.58B2-19.17C2
RN=-634.46+133.31A-8.69B+96.07C-0.51D-9.56AC+3.18AD+4.25BC-4 .06BD+
5.06CD-6.83A2+1.05B2-16.15C2-2.84D2
ωpurity=-670.63+148.41A+24.04B-59.06C+92.68D-4.04AD+17.31CD-8.30A2-
3.65B2-12.03D2
Wherein: Rp--- tp removal rate, %
RN--- nitrogen removal efficiency, %
ωpurity--- guanite purity, %
A——pH
B --- N/P molar ratio
C --- Mg/P molar ratio
D --- Mg/Ca molar ratio
Step 5: carrying out F inspection to each regression equation coefficient and equation model and P examined, obtain ANOVA analysis result and
Significance test result；The P-value < 0.0001 of three models shows model statistically significant highly significant；N
Removal rate regression model coefficient R2> 0.99Adj R-Squared > 0.98, P removal rate regression model coefficient R 2 >
R-Squared > 0.98 0.99Adj, guanite purity removal rate regression model coefficient R 2 > 0.98, Adj R-Squared >
0.98, show that model has good fitting effect.
Table 2N removal rate model analysis
3 P removal rate model analysis of table
4 guanite purity model analysis of table
Step 6: being arbitrarily designated reaction condition in model independent variable setting range, carries out experimental verification, analysis knot to model
Fruit shows the error of experiment value and theoretical value all within 4%, shows the guanite method recycling nitrogen phosphorus mould based on Response Surface Method
Type has good prediction effect.
5 verification test data of table
Step 7: the determining optimal processing parameter method: Design Expert software is used, with guanite purity, N
Removal rate, P removal rate are target value, and different different degrees are arranged according to process goal, each influence factor is arranged in model scope
Adjustable range and bottom line calculate the optimal processing parameter of guanite reaction by Optimization.
Claims (8)
1. the method for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method, characterized by the following steps:
(1) it is based on guanite reaction principle, choosing influences four significant variables that guanite generates: pH, N/P molar ratio, Mg/P
Molar ratio, Mg/Ca molar ratio；
(2) according to Box-Behnken method, guanite reaction experiment scheme is automatically generated using Design-Expert software；
(3) batch experiment is carried out according to experimental program, obtains N removal rate, P removal rate and guanite purity under the conditions of differential responses
Three responses；
(4) fitting is analyzed to the response data preparation obtained in step (3), screens significant variable, established according to significant variable
Secondary multivariate regression models:
In formula: YiFor dependent variable response, β0For constant term, βiFor linear coefficient, βiiFor interaction term coefficient, βijFor secondary term system
Number, XiFor independent variable；
(5) F inspection is carried out to each regression equation coefficient and secondary multivariate regression models and P is examined, obtain ANOVA analysis result and
Significance test result；
(6) it is arbitrarily designated model internal variable numerical value, experimental verification is carried out to each response；
(7) technological parameter determines method: using Design Expert software, with N removal rate, P removal rate and guanite are pure
Degree is target value, and different different degrees are arranged according to process goal, each influence factor adjustable range and bottom line is arranged, passes through
Optimization function determines the optimal processing parameter of guanite reaction.
2. the method according to claim 1 for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method, special
Sign is: the model parameter pH adjustable range in (2) is that 8~10, N/P molar ratio adjustable range is 1~4, Mg/P molar ratio tune
Adjusting range is that 0.8~1.6, Mg/Ca molar ratio adjustable range is 0.8~3.2.
3. the method according to claim 1 for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method, special
Sign is: the method tested in (3) are as follows: and reaction time 60min, standing still for crystals the time is 60min, and mixing speed is 160~
250rpm。
4. the method according to claim 1 for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method, special
Sign is: the method for the significant variable uses of screening is the AlCc method in Design Expert software in (4).
5. the method according to claim 1 for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method, special
Sign is: guanite reacts N removal rate, the second-order response surface model of three responses of P removal rate and guanite purity in (4)
Expression are as follows:
Rp=-422.31+96.01A+19.98B+93.19C-26.61D-1.58AB-4.70AC+1.78AD- 2.60BC+0.94BD
+5.24CD-4.64A2-0.58B2-19.17C2
RN=-634.46+133.31A-8.69B+96.07C-0.51D-9.56AC+3.18AD+4.25BC-4 .06BD+5.06CD-
6.83A2+1.05B2-16.15C2-2.84D2
ωpurity=-670.63+148.41A+24.04B-59.06C+92.68D-4.04AD+17.31CD-8.30A2-3.65B2-
12.03D2
Wherein: Rp--- tp removal rate, %
RN--- nitrogen removal efficiency, %
ωpurity--- guanite purity, %
A --- pH,
B --- N/P molar ratio,
C --- Mg/P molar ratio,
D --- Mg/Ca molar ratio.
6. the method according to claim 1 for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method, special
Sign is: the ANOVA of the significance test of the model in (5), which is analyzed, to be required are as follows: R-Squared (coefficient of determination) > 0.98, Adj
R-Squared (the correction coefficient of determination) > 0.95, Pred R-Squared (the prediction coefficient of determination) > 0.92, Adj R-Squared-
Pred R-Squared > 0.2, Model (model)-significant, Lack of fit (losing analog values)-significant.
7. the method according to claim 1 for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method, special
Sign is: the group number of verification test is 5-8 group in (6), randomly selects the numerical value of four independents variable, at identical conditions instead
It answers；If the absolute error of predicted value and actual value, less than 4%, model has good prediction effect, if it is not, then needing to reform experiment
Obtain more accurately experiment value with correction model.
8. the method according to claim 1 for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method, special
It is: using the Optimization function in Design Expert software, with N removal rate, P removal rate and guanite in (7)
Purity is target value, and different different degrees are arranged according to process goal, be arranged in model scope each influence factor adjustable range and
Bottom line, then software calculate guanite reaction optimal processing parameter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910462615.9A CN110357676A (en) | 2019-05-30 | 2019-05-30 | The method for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910462615.9A CN110357676A (en) | 2019-05-30 | 2019-05-30 | The method for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110357676A true CN110357676A (en) | 2019-10-22 |
Family
ID=68214886
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910462615.9A Pending CN110357676A (en) | 2019-05-30 | 2019-05-30 | The method for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110357676A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI719887B (en) * | 2020-04-13 | 2021-02-21 | 國立臺灣大學 | Method for producing ammonium magnesium phosphate hexahydrate by using livestock manure |
| CN112863612A (en) * | 2021-01-19 | 2021-05-28 | 中国科学院生态环境研究中心 | Optimization method of dry anaerobic digestion mixing ratio of multi-component material |
| CN113096087A (en) * | 2021-04-06 | 2021-07-09 | 清华大学深圳国际研究生院 | Soft measurement method for purity of phosphorus recovery product |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102455285A (en) * | 2010-10-26 | 2012-05-16 | 中国科学院城市环境研究所 | Method for determining precipitate composition in recycling nitrogen and phosphorus from wastewater by guanite precipitation method |
| CN102663199A (en) * | 2012-04-20 | 2012-09-12 | 江苏省交通规划设计院股份有限公司 | Sound barrier optimization design method on basis of response surface analysis |
-
2019
- 2019-05-30 CN CN201910462615.9A patent/CN110357676A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102455285A (en) * | 2010-10-26 | 2012-05-16 | 中国科学院城市环境研究所 | Method for determining precipitate composition in recycling nitrogen and phosphorus from wastewater by guanite precipitation method |
| CN102663199A (en) * | 2012-04-20 | 2012-09-12 | 江苏省交通规划设计院股份有限公司 | Sound barrier optimization design method on basis of response surface analysis |
Non-Patent Citations (1)
| Title |
|---|
| 李莉等: "基于响应面法优化MAP法处理垃圾渗滤液工艺的研究", 《环境工程学报》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI719887B (en) * | 2020-04-13 | 2021-02-21 | 國立臺灣大學 | Method for producing ammonium magnesium phosphate hexahydrate by using livestock manure |
| CN112863612A (en) * | 2021-01-19 | 2021-05-28 | 中国科学院生态环境研究中心 | Optimization method of dry anaerobic digestion mixing ratio of multi-component material |
| CN113096087A (en) * | 2021-04-06 | 2021-07-09 | 清华大学深圳国际研究生院 | Soft measurement method for purity of phosphorus recovery product |
| WO2022213958A1 (en) * | 2021-04-06 | 2022-10-13 | 清华大学深圳国际研究生院 | Soft measurement method for purity of phosphorus recovery product |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110357676A (en) | The method for determining guanite recycling nitrogen phosphorus technological parameter based on Response Surface Method | |
| Zheng et al. | Stoichiometry of carbon, nitrogen, and phosphorus in soil: Effects of agricultural land use and climate at a continental scale | |
| Rahaman et al. | Effects of various process parameters on struvite precipitation kinetics and subsequent determination of rate constants | |
| Ye et al. | Recovering phosphorus as struvite from the digested swine wastewater with bittern as a magnesium source | |
| CN102365925B (en) | Method for determining ability of plant on using nitrate | |
| CN104529632B (en) | A kind of inland salt-soda soil drip irrigation liquid fertilizer and preparation method thereof | |
| CN104926430A (en) | Nutrient solution for hydroponic lettuce and preparation method and application of nutrient solution | |
| CN114230110A (en) | Short-range intelligent phosphorus removal and medicine addition control method, equipment and system for sewage treatment | |
| CN103589434B (en) | A kind of preparation method of low pH value soil conditioner | |
| Jiang et al. | Comparison of RZWQM2 and DNDC models to simulate greenhouse gas emissions under combined inorganic/organic fertilization in a subsurface-drained field | |
| CN107449858A (en) | A kind of method for determining plant ammonium nitrogen utilization ratio | |
| Daneshgar et al. | Side-stream phosphorus recovery in activated sludge processes | |
| Kapland et al. | Organic Matter Relationship to Soil Nutrient Status and Aluminum Toxicity in Alfalfa 1 | |
| CN106478300B (en) | A kind of acid soil improvement drop cadmium fertilizer reducing cadmium content in rice rice | |
| CN103324851A (en) | Method for controlling farmland soil nitrogen non-point source pollution with carbon | |
| CN109271753A (en) | The process parameter optimizing method of vanadium wastewater ammonia nitrogen recycling based on response surface analysis | |
| CN109279991A (en) | A kind of fulvic acid compound fertilizer of potassium dihydrogen phosphate and preparation method thereof | |
| Della Lunga et al. | Struvite effects on rice growth and productivity under flood-irrigation in the greenhouse. | |
| AU784162B2 (en) | A method of managing crop production | |
| Kalvakaalva et al. | Mass-balance process model of a decoupled aquaponics system | |
| CN104512865B (en) | Except in silicon and reaction neutralize medicament ammonia addition control method | |
| CN113366955A (en) | Bio-feritlizer fertilization system | |
| Wen et al. | Effects of initial phosphate concentration on physiological aspects of suspension cultures of rice cells: a kinetic study | |
| CN102320880A (en) | Witloof nutrient solution and method of use thereof | |
| Santamaría et al. | Modelling of phosphorus accumulation in an aeroponic coriander crop |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20191022 |
|
| RJ01 | Rejection of invention patent application after publication |