Based on the fermentation maturity degree criterion of humus content
[technical field]
The present invention relates to fermentation technical field, specifically a kind of fermentation maturity degree criterion based on humus content.
[background technology]
Film covering high-temperature aerobic fermenting process essence is organic mineralising and humification process, the Humus material that final formation is stable in a large number, mainly comprises humic acid (HA), fulvic acid (FA) and humin (HM).Humic acid most importantly in soil ulmin enlivens component, and its physical and chemical properties change is for judging fermentation maturity degree and fermented quality important role.Along with the carrying out of aerobic fermentation, small molecules fulvic acid is gradually by mineralising or conversion, and content declines to a great extent, and macromole humic acid significantly increases, and becomes the main component of humic acid, and the change words paying close attention to HA are more meaningful.With the development of spectroscopic technique, it has been widely used in the analysis of soil humic acid, and using for reference these methods effectively can understand aerobic fermentation degree of humification from structure of matter angle.
[summary of the invention]
Present method, by observing the change of humic acid spectral signature, is analyzed humic acid and fulvic acid spectral signature in mud film covering high-temperature aerobic fermenting process and is changed the relation with rotten degree, finally determine that it can as the method judging sludge fermentation rotten degree.
For achieving the above object, design a kind of fermentation maturity degree criterion based on humus content, Humus material comprises humic acid HA, fulvic acid FA and humin HM, it is characterized in that, priority multi-point sampling successively in high-temperature aerobic fermentation process, by humic acid HA in working sample and the change of fulvic acid FA spectral signature, judge fermentation maturity degree and fermented quality, comprise the following steps:
(1) extract humic acid HA and fulvic acid FA, often organize in sample and take a certain amount of air-dry sample, according to solid-to-liquid ratio W/V, with dry weight basis 1:20, use 0.1mol/LNa
4p
2o
7+ 0.1mol/LNaOH is in 40 DEG C of water-bath lixiviate 24h, centrifugal 20min under 4000r/min, supernatant liquor 0.45 μm of membrane filtration, obtain humic acid extracting solution, get a certain amount of humic acid extracting solution, pH1.0-2.0 is modulated to 6mol/LHCl, be placed in 60 DEG C of water-bath 4h, humic acid in solution is fully separated with fulvic acid, under 4000r/min, centrifugal 20min obtains humic acid HA and precipitates, filtering-depositing obtains humic acid HA extract and fulvic acid FA extracting solution, the mixed solution desalting and purifying of humic acid HA extract with 0.1mol/L HCl+0.3mol/L HF, humic acid HA extract after purifying is dried to constant weight in 80 DEG C, sealing is preserved,
(2) gel chromatography analytical procedure, filling dextrane gel, cumulative volume 303ml, loading height 67cm, internal diameter 25mm, glass column as chromatographic column, get 1.0ml HA extracting solution respectively and 1.0ml FA extracting solution slowly adds gel top layer, with the ultrapure water of pH=6.8 as elutriant, be 1.0ml/min with peristaltic pump coutroi velocity, the every 5ml of automatic collector collects sample once, recording void volume with 1.0ml 2% dextran solution is 100ml, the sample eluent of collecting measures the absorbancy of 280nm, and the absorbancy corresponding according to eluting liquid sum draws out elution curve, fermentation maturity degree is judged according to described elution curve.
In above-mentioned high-temperature aerobic fermentation process, successively the step of multi-point sampling is as follows successively:
(1) before high-temperature aerobic fermentation, former dewatered sludge, auxiliary material and the fertilizer that becomes thoroughly decomposed are carried out certain proportioning, by material balance after mixing, mixture initial aqueous rate is 55-62%, and wherein feed back water ratio is about 50%-55%, and C/N is 20:1-30:1;
(2) mixture stockpile body is maintained more than 55 DEG C high temperature about 6d, carry out first time fermentation, first time fermentation is 12d, and in fermenting process, carry out multi-point sampling respectively at 0d, 3d, 9d, 12d, each sampling quantity is about 2kg;
(3) be transferred in film covering high-temperature aerobic fermentation unit by the mixture stockpile body after first time fermentation ends and carry out second time fermentation, second time fermentation needs 12d, and in fermenting process, respectively at 15d and 24d multi-point sampling, each sampling quantity is about 2kg;
(4) sample of sampling acquisition is at 40 DEG C of oven drying at low temperatures, pulverizes as dry sample, fully grinds during mensuration, and crossing aperture is after the sieve of 0.16mm, carries out analysis and measures.
Described high-temperature aerobic fermentation device is by sensor mounting hole, functional membrane stationary installation, casing, functional membrane, trapped well device, water pump, oxygen supply blower fan, variable valve, aerating pipelines, aerator tank, Electric Appliance Cabinet forms, the skin of described casing is provided with functional membrane stationary installation, described functional membrane stationary installation is fixed with functional membrane, described bottom half one end is provided with water pump, box house is extended successively by trapped well device, the described bottom half the other end is provided with oxygen supply blower fan, oxygen supply blower fan passes through aerating pipelines successively, aerator tank extends box house, described box house is provided with sensor mounting hole, inside be provided with sensor, described oxygen supply blower fan, water pump, sensor is by Electric Appliance Cabinet control linkage.
The present invention is about the decision method of fermentation maturity degree, gel chromatography analysis means is utilized to analyze humic acid in aerobic fermentation process and fulvic acid content, can accurately judge aerobic fermentation humification process and rotten degree from the quantitative change angle of soil ulmin, provide Data support for following resourceization utilizes.
[accompanying drawing explanation]
Fig. 1-1 is mud film covering high-temperature aerobic fermentation unit structural representation
Fig. 1-2 is mud film covering high-temperature aerobic fermentation unit structural representation
The G-75 gel elution curve of HA in the fermentation of Fig. 2-1 mud film covering high-temperature aerobic
The G-75 gel elution curve of FA in the fermentation of Fig. 2-2 mud film covering high-temperature aerobic
Thetagram in the fermentation of Fig. 2-3-1 mud film covering high-temperature aerobic
Thetagram in the fermentation of Fig. 2-3-2 mud film covering high-temperature aerobic
Seed germination index graphic representation in the fermentation of Fig. 2-4 mud film covering high-temperature aerobic
1. sensor mounting hole 2. functional membrane stationary installation 3. casing 4. functional membrane 5. trapped well device 6. water pump 7. oxygen supply blower fan 8. variable valve 9. aerating pipelines 10. aerator tank 11. Electric Appliance Cabinet.
[embodiment]
Now by reference to the accompanying drawings and embodiment technical scheme of the present invention is further elaborated, believe it is clearly for a person skilled in the art.
Embodiment
A, raw material
Mud film covering high-temperature aerobic fermentation raw material, raw material: adopt the fresh dewatered sludge of south bridge Sewage Plant, auxiliary material: adopt stalk, feed back: enchashment shape sludge treatment field is with batch ageing material, and wherein feed back water ratio is about 50-55%.Design parameter is as shown in the table:
Project |
Water ratio |
Volatile matter |
Total carbon |
Organic |
Total nitrogen |
Mud |
82.9 |
72.8 |
37.8 |
61.5 |
9.1 |
Stalk |
11.9 |
84.7 |
42.3 |
72.9 |
0.76 |
B, test design
A, mud film covering high-temperature aerobic fermentation unit, as shown in Figure 1, by sensor mounting hole, functional membrane stationary installation, casing, functional membrane, trapped well device, water pump, oxygen supply blower fan, variable valve, aerating pipelines, aerator tank, Electric Appliance Cabinet forms, the skin of described casing is provided with functional membrane stationary installation, described functional membrane stationary installation is fixed with functional membrane, described bottom half one end is provided with water pump, box house is extended successively by trapped well device, the described bottom half the other end is provided with oxygen supply blower fan, oxygen supply blower fan passes through aerating pipelines successively, aerator tank extends box house, described box house is provided with sensor mounting hole, inside be provided with sensor, described oxygen supply blower fan, water pump, sensor is by Electric Appliance Cabinet control linkage.
B, experimental implementation
Before high-temperature aerobic fermentation, former dewatered sludge, auxiliary material and the fertilizer that becomes thoroughly decomposed are carried out certain proportioning, by material balance after mixing, mixture initial aqueous rate is 55 ~ 62%, and wherein feed back water ratio is about 50%-55%, and C/N is 20:1 ~ 30:1.Heap body maintains more than 55 DEG C high temperature about 6d, and top temperature is 69.08 DEG C, reaches innoxious standard-required, and one time fermentation is 12d.After one time fermentation terminates, windrow is transferred to Secondary Fermentation film to cover in fermentation unit, Secondary Fermentation is 12d.Respectively at 0d, 3d, 9d, 12d, 15d and 24d sampling, multi-point sampling after turning evenly, each sampling quantity is about 2kg, sample, at 40 DEG C of oven drying at low temperatures, is pulverized as dry sample, is fully ground during mensuration, cross the sieve that aperture is 0.16mm, ensure that sample has good representativeness.
C, analytical procedure
Gel chromatography
The glass column of Sephadex G-75 gel (cumulative volume 303ml, loading height 67cm, internal diameter 25mm) will be loaded as chromatographic column.Get 1.0ml HA respectively and FA extracting solution slowly adds gel top layer, with the ultrapure water of pH=6.8 as elutriant, be 1.0ml/min with peristaltic pump coutroi velocity, the every 5ml of automatic collector collects sample once.Recording void volume (V0) with 1.0ml Dextran Blue-2000 dextran solution (2%) is 100ml.The sample eluent of collecting measures the absorbancy of 280nm, and the absorbancy corresponding according to eluting liquid sum draws out elution curve.
D, results and analysis
The gel chromatography analytical procedure of a, HA and FA
Can find from the HA elution curve of Fig. 2-1, the aerobic fermentation mud that the 24d that banks up is later, the peak area of its HA elution curve is far longer than the peak area of initial 0d sludge aerobic fermentation elution curve of banking up, and this illustrates that sludge aerobic fermentation is after banking up, and the content of HA improves greatly.HA only has an absorption peak (V=100ml), and the peak value of its absorption peak of HA of fermentation 24d is approximately 1.8 times of 0d.This illustrates in HA the existence only having macromolecular substance, and along with the carrying out of aerobic fermentation, in organic constituent, extractible HA concentration significantly improves.
Show from the FAG-75 gel elution curve of Fig. 2-2, the peak area of its FA elution curve of mud of fermentation 24d is lower than the face, peak of initial (0d) mud elution curve, and this illustrates that mud is after aerobic fermentation, and the content of FA have dropped on the contrary.Curve has two obvious absorption peak: V=100ml and V=300ml, describe FA and be made up of the material of the molecular weight that varies in size, by fermentation, in FA, the content of macromolecular substance declines, and in FA, the content of macromolecular substance reduces 30%; And the content of small molecular weight material does not significantly change before and after composting.Can also find from figure, FA small molecular material more than the content of macromolecular substance, the former concentration is about about 3 times of the latter's concentration.
B, the change of heap temperature and seed germination index (GI) in mud film covering high-temperature aerobic fermenting process
The change of heap temperature reflects the change of microorganism active in aerobic fermentation process, when heap temperature and envrionment temperature reach unanimity, no longer includes considerable change, shows that organic decomposition is close to completely, can think that fermentation has reached stable.In mud film covering high-temperature aerobic fermenting process, as Figure 2-3, heap temperature reduces gradually through temperature raising period with after the pliotherm period, and after one time fermentation 9d, heap temperature obviously declines in heap temperature change.This result shows, after Primary Fermentation, heap body degradable organic matter is degraded completely substantially, and fermentation reaches stable substantially.After entering Secondary Fermentation 9d, heap temperature declines fast and close to envrionment temperature, can think that mud becomes thoroughly decomposed completely after aerobic fermentation.
In mud film covering high-temperature aerobic fermenting process, GI change as in Figure 2-4, and after the fermentation of 12d film covering high-temperature aerobic, GI reaches 65.0%, the mud phytotoxicity basically eliminate after aerobic fermentation is described, reaches acceptable degree.In the Secondary Fermentation stage, GI raises gradually, reaches 88.0% in 24d, afterwards again through 6d latter stage of ripening, GI does not have considerable change, illustrates through 24d aerobic fermentation, become thoroughly decomposed completely, this is consistent with the conclusion drawn as fermentation maturity degree judge index with heap temperature.
Can think from the rule of heap temperature change and seed germination index change, aerobic fermentation reaches in 12d and substantially becomes thoroughly decomposed, and 24d becomes thoroughly decomposed completely.Humic acid spectral signature change in mud film covering high-temperature aerobic fermenting process can be combined with this conclusion and judge fermentation maturity degree.
Conclusion is as follows:
After aerobic fermentation 24d, through the gel chromatography analysis of HA and FA, in FA, the content of macromolecular substance reduces 30%, small-molecule substance concentration is about about 3 times of macromolecular substance concentration, the peak value of HA absorption peak is approximately 1.8 times of 0d, in conjunction with heap temperature and GI variation tendency, the judge index of fermentation maturity degree can be it can be used as.