CN103217356A - Method for rapidly determining hydrogen production activity of anaerobic sludge and device used by same - Google Patents

Abstract

The invention provides a method for rapidly determining the hydrogen production activity of anaerobic sludge. The method comprises the following steps of: firstly, obtaining a hydrogen amount generated in an anaerobic sludge fermentation process; drawing a standard relation curve graph of the hydrogen amount and fermentation time; when the hydrogen amount and the fermentation time are in a linear relation to obtain the value of a gradient k; and calculating a maximum ratio hydrogen production activity value SHAm of the hydrogen production activity of the anaerobic sludge. The invention further provides a set of device, and the device is used for determining the yield of hydrogen so as to conveniently calculate the value of the SHAm. With the adoption of the method and the device disclosed by the invention, the SHAm value of the anaerobic hydrogen production sludge can be rapidly and accurately determined, so that the hydrogen production activity of the anaerobic sludge is accurately characterized. According to the method disclosed by the invention, not only can the hydrogen production activity of the anaerobic sludge and the sludge concentration needed by keeping a certain hydrogen production activity value in a reactor be accurately determined, but also a variation condition of performances of the reactor under different operation conditions can be evaluated. Therefore, the method disclosed by the invention has the great help to stably operate an anaerobic hydrogen production reactor.

Description

A kind of fast measuring anaerobic sludge produces the method for hydrogen activity and used device thereof

Technical field

The present invention relates to the fermentation and hydrogen production technical field, be specifically related to a kind of fast measuring anaerobic sludge and produce the method for hydrogen activity and used device thereof.

Background technology

Hydrogen is considered to the fuel that a kind of energy substitutes methane and has good prospect, can utilize multiple discarded object to make hydrogen by anaerobic digestion usually.Compare with the chemical hydrogen manufacturing of routine, fermentative hydrogen production technology not only can be carried out under room temperature and normal pressure, and the discarded object that can utilize industry and agricultural generation is as raw material, so biological hydrogen production helps waste disposal and resource reclaims.

In the startup or operational process of anaerobic fermentation hydrogen reactor, must hold the product hydrogen activity mud of q.s in the reactor.Therefore, seek easy method fast measuring and produce hydrogen sludge concentration and active most important the monitoring of anaerobic hydrogen-generating reactor.The method of conventional mensuration microbial activity has: methods such as most probable number MPN (MPN), atriphos (ATP) analysis and measuring desaturase liveness.These methods perhaps can determine to produce the hydrogen activation of microorganism.Yet the most probable number MPN detection method is impracticable, because it needs long doubling time and strict anaerobic environment, and has any problem when calculating the bacterium of some kinds.And ATP analytic approach and measuring desaturase liveness method are not to determine the reliable method of microbial activity.

Summary of the invention

In order to address the above problem, the purpose of this invention is to provide the method that a kind of fast measuring anaerobic sludge produces hydrogen activity.

Another object of the present invention provides a covering device, and the output that this device can fast measuring hydrogen is so that can calculate SHA _mValue.

At first, the invention provides the method that a kind of fast measuring anaerobic sludge produces hydrogen activity, its step is as follows:

(1) at first measures the amounts of hydrogen that produces in the anaerobic sludge sweat by related device;

(2) draw described amounts of hydrogen and fermentation time standard relationship curve map;

(3) when described amounts of hydrogen and fermentation time are linear, draw the value of slope k;

(4) calculate the high specific that can characterize this anaerobic sludge product hydrogen activity and produce hydrogen activity SHA _m, its computing formula is as follows:

${\mathrm{SHA}}_m=\frac{k\×24}{V_{R}X}\×\frac{T_0}{T_1}$

In the formula, T ₀(K) be temperature 273.15K under the standard state; T ₁(K) be the temperature of reactor; V _R(L) be reactor volume; X (g-VSS/L) is mud (microorganism) concentration; K (mL-H ₂/ h) be meant the slope that described amounts of hydrogen and fermentation time are linear.

SHA _mThe derivation of expression formula is as follows:

The relation that growth of microorganism and product generate in the anaerobic hydrogen-generating process can be set forth with Luedeking – Piret model:

$\frac{{\mathrm{dP}}_i}{\mathrm{dt}}={\mathrm{\α}}_i\frac{\mathrm{dX}}{\mathrm{dt}}+{\mathrm{\β}}_{i}X---\left(1\right)$

α _iBe the product i formation coefficient of growth coupling connection, β _iBe the product i formation coefficient of non-growth coupling connection, t (h) is the reaction time, and X (g-VSS/L) is mud (microorganism) concentration, and P (g-COD/L) is a production concentration.First α on equation (1) the right _iDX _iDt is the product i generating rate of growth coupling, and the growing amount of the cell growth of the relevant thalline of its expression and the material i of its production is certain proportionate relationship, non-growth coupled product generating item (β _iX) growing amount of then representing the material i of the concentration of all thalline and its generation is certain proportionate relationship.Equation (1) deformable is:

$\frac{{\mathrm{dP}}_i}{\mathrm{Xdt}}={\mathrm{\α}}_i\frac{\mathrm{dX}}{\mathrm{Xdt}}+{\mathrm{\β}}_i$

$\frac{{\mathrm{dP}}_i}{\mathrm{Xdt}}={\mathrm{\α}}_i\mathrm{\μ}+{\mathrm{\β}}_i---\left(2\right)$

DP _i/ dt/X represents the specific production rate of product i, μ (d ^-1) expression microorganism specific growth rate.With μ and dP _i/ dt/X is respectively horizontal ordinate mapping, can get one with α _iBe slope, β is the straight line of intercept.Typical matched curve β _H2Value be about 0, this generation that shows hydrogen in the sweat is all relevant with microbial growth.So the relation of hydrogen output and concentration of substrate can be used equation (3) expression:

$\frac{{\mathrm{<figure-callout\; id="2"\; label="dP\; H"\; filenames="HDA00003065985100041.png"\; state="\{\{state\}\}">dP</figure-callout>}}_{H_{}}}{\mathrm{dt}}=-{\mathrm{<figure-callout\; id="2"\; label="Y\; H"\; filenames="HDA00003065985100041.png"\; state="\{\{state\}\}">Y</figure-callout>}}_{H_{}}\&times;\frac{\mathrm{dS}}{\mathrm{dt}}---\left(3\right)$

S (mmol/L) is the concentration of substrate; Y _H2(mL-H ₂/ mmol) be the yield coefficient of hydrogen.

In the sequencing batch reactor of ferment for hydrogen production, equation (3) deformable is:

$\frac{\mathrm{dS}}{\mathrm{dt}}=-\frac{1}{{\mathrm{<figure-callout\; id="2"\; label="Y\; H"\; filenames="HDA00003065985100041.png"\; state="\{\{state\}\}">Y</figure-callout>}}_{H_{}}\&times;V_R}\&times;\frac{{\mathrm{<figure-callout\; id="2"\; label="dV\; H"\; filenames="HDA00003065985100041.png"\; state="\{\{state\}\}">dV</figure-callout>}}_{H_{}}}{\mathrm{dt}}\&times;\frac{T_0}{T_1}---\left(4\right)$

V _H2(mL) be the cumulative volume of hydrogen; V _R(L) be the volume that reaction mass occupies in whole reactor; T ₀(K) be temperature (273.15K) under the standard state; T ₁(K) be the temperature of reactor.

The available Monot's equation of the degraded of substrate is described in the reactor:

$\frac{\mathrm{dS}}{\mathrm{dt}}=-\frac{U_{\max }\&times;S\&times;X}{K_s+S}---\left(5\right)$

U _Max(d ^-1) expression substrate high specific absorption rate, K _s(mmol/L) be the semi-saturation constant.Can get equation (6) in conjunction with equation (4) and (5):

$\frac{1}{{\mathrm{<figure-callout\; id="2"\; label="Y\; H"\; filenames="HDA00003065985100041.png"\; state="\{\{state\}\}">Y</figure-callout>}}_{H_{}}\&times;V_R}\&times;\frac{{\mathrm{<figure-callout\; id="2"\; label="dV\; H"\; filenames="HDA00003065985100041.png"\; state="\{\{state\}\}">dV</figure-callout>}}_{H_{}}}{\mathrm{dt}}\&times;\frac{T_0}{T_1}=\frac{U_{\max }\&times;S\&times;X}{K_s+S}$

$\frac{1}{V_R}\&times;\frac{{\mathrm{dV}}_{H_2}}{X\&times;\mathrm{dt}}\&times;\frac{T_0}{T_1}=\frac{{\mathrm{<figure-callout\; id="2"\; label="Y\; H"\; filenames="HDA00003065985100041.png"\; state="\{\{state\}\}">Y</figure-callout>}}_{H_{}}\&times;U_{\max }\&times;S}{K_s+S}$

$\frac{1}{V_R}\&times;\frac{{\mathrm{dV}}_{H_2}}{X\&times;\mathrm{dt}}\&times;\frac{T_0}{T_1}={\mathrm{<figure-callout\; id="2"\; label="Y\; H"\; filenames="HDA00003065985100041.png"\; state="\{\{state\}\}">Y</figure-callout>}}_{H_{}}\&times;U_{\max }\&times;\frac{S}{K_s+S}---\left(6\right)$

Begin and the stabilization sub stage in fermentation, S is far longer than K _s, so equation (6) can be reduced to:

$\frac{1}{V_R}\&times;\frac{{\mathrm{dV}}_{H_2}}{X\&times;\mathrm{dt}}\&times;\frac{T_0}{T_1}={\mathrm{<figure-callout\; id="2"\; label="Y\; H"\; filenames="HDA00003065985100041.png"\; state="\{\{state\}\}">Y</figure-callout>}}_{H_{}}\&times;U_{\max }---\left(7\right)$

Here, we define the SHA of anaerobic hydrogen-generating mud _m(mL-H ₂/ g-VSS/d) be:

${\mathrm{SHA}}_m={\mathrm{<figure-callout\; id="2"\; label="Y\; H"\; filenames="HDA00003065985100041.png"\; state="\{\{state\}\}">Y</figure-callout>}}_{H_{}}\&times;U_{\max }---\left(8\right)$

So equation (8) also can be write as:

$\frac{1}{V_R}\&times;\frac{{\mathrm{dV}}_{H_2}}{X\&times;\mathrm{dt}}\&times;\frac{T_0}{T_1}={\mathrm{SHA}}_m---\left(9\right)$

The accumulation typical curve of the hydrogen that produces in the sweat as shown in Figure 1.After the hold-up time, the amounts of hydrogen of generation increases along with the increase of fermentation time, and according to equation (9) as can be known, in one section initial fermentation time, the amounts of hydrogen and the fermentation time of generation are linear.Therefore, the SHA of mud _mBeing worth available equation (10) calculates:

${\mathrm{SHA}}_m=\frac{k\&times;24}{V_{R}X}\&times;\frac{T_0}{T_1}---\left(10\right)$

K (mL-H ₂/ h) be meant the slope that above-mentioned amounts of hydrogen and fermentation time are linear.

According to formula 8, U _MaxBe substrate high specific absorption rate, and Y _H2Be the yield coefficient of hydrogen to substrate, if the degradation amount of substrate is n mol, then the amounts of hydrogen of Sheng Chenging is for being n*Y _H2Mol.So U _MaxWith Y _H2Product (be SHA _m) be the high specific generating rate of hydrogen, so SHA _mThe high specific that can characterize anaerobic sludge produces hydrogen activity.

Further, the invention provides a covering device, this device is used for measuring the output of hydrogen so that can calculate SHA _mValue, it comprises installation for fermenting, wash mill, gas collector; Described wash mill is connected between described installation for fermenting and the described gas collector, in order to remove the gas except that hydrogen that described installation for fermenting produces.

Preferably, described gas collector comprises gas collector and device for measuring volumetric flow of fluid.

Beneficial effect of the present invention is as follows:

The present invention has at first proposed one and has been used to characterize the new ideas that anaerobic sludge produces hydrogen activity: high specific produces hydrogen activity, and (special hydrogen-producing activity is abbreviated as SHA _m), and set up one and measured product hydrogen mud SHA _mThe method of value has also made up mensuration SHA _mDevice.Utilize this method and apparatus can rapid and accurate determination the SHA of anaerobic hydrogen-generating mud _mValue, thus accurately characterize the product hydrogen activity of anaerobic sludge.This method can not only accurately be measured and keep the required sludge concentration of a certain product hydrogen activity value in the product hydrogen activity of anaerobic sludge and the reactor, can also evaluate reactor changes of properties situation under the different operating condition.Therefore the method for being set up among the present invention is very helpful to stable operation anaerobic hydrogen-generating reactor.

Description of drawings

Fig. 1: the standard relationship curve of hydrogen gas accumulation amount and fermentation time;

Fig. 2: hydrogen volume determinator;

The SHA that Fig. 3: embodiment 3 is measured _mValue;

The SHA that Fig. 4: embodiment 4 is measured _mValue;

The SHA that Fig. 5: embodiment 5 is measured _mValue;

The SHA that Fig. 6: embodiment 6 is measured _mValue; :

Fig. 7: the relative increase percentage that produces the hydrogen sludge concentration: be 3g-VSS/L (A), under the different situation of concentration of substrate in sludge concentration; (B) be 3.4g-COD/L at concentration of substrate, the situation that sludge concentration is different.

Wherein, the label among Fig. 2 is as follows: 1-fermentation tank (300mL); 2-contain the wash bottle of 5mol/L NaOH; 3-gas collector; 4-measuring bottle; 5-constant temperature Vib..

Embodiment

Introduce the present invention in detail below in conjunction with accompanying drawing and embodiment thereof.But protection of the present invention orientation is not limited to following example, should comprise the full content in claims.

Embodiment 1 measures anaerobic hydrogen-generating mud SHA _mThe experimental provision of value

It among Fig. 2 the experimental provision of measuring hydrogen output.Described installation for fermenting is a fermentation tank, and described wash mill is the washing flask, and described gas collector comprises gas collector and measuring bottle.The principle of work of this device is as follows:

This device is a continuous gas releasing means, and it comprises fermentation tank (serum bottle), washing flask, gas collector, measuring bottle and the Vib. (constant temperature operation down) of a 300mL.Anaerobic hydrogen-generating mud and substrate with concentration known joins respectively in the serum bottle earlier, adds distilled water then volume-adjustment is arrived 290mL.The pH value of solution is regulated with HCl or the KOH of 5mol/L.Afterwards, feed 30s nitrogen to remove away the oxygen in the solution in serum bottle, ventilation clogs with the diaphragm of rubber plug immediately and pinions with the plastics firmware after finishing.Then fermentation tank is at the uniform velocity vibrated in being put into Vib. and be controlled at temperature required down.The gas that produces in the fermentation tank feeds and contains 5mol/L NaOH solution to remove carbon dioxide wherein, and the hydrogen volume of generation is measured with liquid displacement technique, and promptly the liquid of only measuring in the measuring bottle gets final product.

Embodiment 2SHA _mThe mensuration of value

The experiment equipment therefor is with embodiment 1.

At sucrose concentration is that 3.4g-COD/L, sludge concentration are that 3g-VSS/L and temperature are under 38.5 ℃, and the pH value is 4 o'clock mensuration SHA _m, its step is as follows:

(1) at first obtains the amounts of hydrogen that produces in the anaerobic sludge sweat by the liquid volume in the measuring bottle;

(2) draw described amounts of hydrogen and fermentation time standard relationship curve map (as shown in Figure 1);

(3) when described amounts of hydrogen and fermentation time were linear, drawing the slope k value was 17.3 ± 0.4;

(4) calculate the high specific that can characterize this anaerobic sludge product hydrogen activity and produce hydrogen activity value SHA _m, its computing formula is as follows:

${\mathrm{SHA}}_m=\frac{k\&times;24}{V_{R}X}\&times;\frac{T_0}{T_1}$

SHA _m=[(17.3 ± 0.4) * 24*273.15]/(0.29*3*311.65), the final SHA that gets _mBe 419 ± 11.

Embodiment 3 different pH values are SHA down _mBe worth measuring

The experiment equipment therefor is with embodiment 1.

Experiment method therefor step and other conditions are with embodiment 2, test used pH value and be respectively 4.5,5,5.5,6,6.5 and at 7 o'clock, its corresponding k value is respectively 28.3 ± 0.6,34.1 ± 1.6,37 ± 0.3,31.3 ± 0.3,24.9 ± 2.5 and 20.5 ± 1.7; The SHA that records _mValue should be 685 ± 15,823 ± 29,896 ± 8,757 ± 8,603 ± 61 and 496 ± 40mL-H mutually ₂/ g-VSS/d(as shown in Figure 3).

SHA during the different concentration of substrate of embodiment 4 _mBe worth measuring

Experiment equipment therefor and step are with embodiment 2.

At pH is 5.5, and sludge concentration is that 3g-VSS/L and temperature are under 38.5 ℃, measures concentration of substrate respectively and be 2.92,6.03,8.75,11.87,14.26,17.54 and 20.47 o'clock SHA _mValue, its corresponding k value is respectively: 22.9 ± 1.2,31.5 ± 0.5,39.6 ± 1.7,46.6 ± 5.3,59.9 ± 2,51.7 ± 1.6 and 43.4 ± 2.The SHA that records _mValue should be 555 ± 30,761 ± 13,958 ± 42,1170 ± 86,1400 ± 49,1232 ± 58 and 1049 ± 50mL-H mutually ₂/ g-VSS/d(as shown in Figure 4).

SHA during the different sludge concentration of embodiment 5 _mBe worth measuring

Experiment equipment therefor and step are with embodiment 2.

In the pH value is 5.5, and sucrose concentration is that 3.4g-COD/L and temperature are under 38.5 ℃, measures sludge concentration respectively and be 1,2,3,4,5,7 and the SHA during 10g-VSS/L _mValue, its corresponding k value is respectively: 35.6 ± 2.9,40 ± 1.9,36 ± 0.6,48.1 ± 3.9,46.5 ± 4.6,56 ± 6 and 62.9 ± 2.2.The SHA that records _mValue should be 2584 ± 215,1450 ± 68,872 ± 15,872 ± 70,675 ± 67,591 ± 73 and 456 ± 16mL-H mutually ₂/ g-VSS/d(as shown in Figure 5).

SHA during embodiment 6 different temperatures _mBe worth measuring

Experiment equipment therefor and step are with embodiment 2.

In the pH value is 5.5, and sucrose concentration is that 3.4g-COD/L and sludge concentration are under the 3g-VSS/L, the SHA when measuring temperature respectively and being 20,30,40,45 and 55 ℃ _mValue, its corresponding k value is respectively: 33.6 ± 3.1,59 ± 2.4,111 ± 0.8,177.3 ± 6.3 and 278.7 ± 7.The SHA that records _mValue should be 864 ± 80,1468 ± 60,2672 ± 20,4200 ± 150 and 6400 ± 160mL-H mutually ₂/ g-VSS/d(as shown in Figure 6).

The quantity that it should be noted that hydrogen-producing bacteria especially has the possibility of growth in the process of experiment.Fig. 7 has set forth in the following relative situation that increases of hydrogen-producing bacteria quantity of different concentration of substrate (Fig. 7 A) and sludge concentration (Fig. 7 B).Particularly under high concentration of substrate or low sludge concentration, the trend of this increase is more obvious.Therefore, concentration of substrate and sludge concentration all need careful selection in the test.

The above description of this invention is illustrative, and nonrestrictive, and those skilled in the art is understood, and can carry out many modifications, variation or equivalence to it within spirit that claim limits and scope, but they will fall within the scope of protection of the present invention all.

Claims (3)

1. a fast measuring anaerobic sludge produces the method for hydrogen activity, and its step is as follows:

(1) at first measures the amounts of hydrogen that produces in the anaerobic sludge sweat;

(2) draw described amounts of hydrogen and fermentation time standard relationship curve map;

(3) when described amounts of hydrogen and fermentation time are linear, draw the value of slope k;

(4) calculate the high specific that can characterize this anaerobic sludge product hydrogen activity and produce hydrogen activity value SHA _m, its computing formula is as follows:

${\mathrm{SHA}}_m=\frac{k\&times;24}{V_{R}X}\&times;\frac{T_0}{T_1}$

In the formula, T ₀(K) be temperature 273.15K under the standard state; T ₁(K) be the temperature of reactor; V _R(L) be reactor volume; X (g-VSS/L) represents microorganism concn; K (mL-H ₂/ h) be meant the slope that described amounts of hydrogen and fermentation time are linear.

2. the device of a fast measuring hydrogen output is characterized in that, it comprises installation for fermenting, wash mill, gas collector; Described wash mill is connected between described installation for fermenting and the described gas collector, in order to remove the gas except that hydrogen that described installation for fermenting produces.

3. device as claimed in claim 2 is characterized in that described gas collector comprises gas collector and device for measuring volumetric flow of fluid.

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