CN201268575Y - Apparatus for preparing hydrogen from sodium borohydride - Google Patents

Abstract

The utility model discloses a device for producing hydrogen by applying sodium borohydride. The device comprises a reaction device and a control device, wherein a microprocessing unit of the control unit is respectively and electrically connected with an analog-digital conversion circuit, a keyboard, an LCD display screen, a heat radiator and an isolation driving circuit; the analog-digital conversion circuit is respectively and electrically connected with hydrogen sensors, pressure sensors and thermistors; the isolation driving circuit is respectively and electrically connected with a low-power hydraulic pump and a high-speed solenoid valve; and one pressure sensor of the pressure sensors, one thermistor of the thermistors and the hydrogen sensors are installed on a reaction chamber. The method for hydrogen-production reaction by using the sodium borohydride adopts the low-power hydraulic pump, and the reaction speed and the hydrogen production amount are controlled by automatically adjusting the flow of the sodium borohydride solution added in the reaction chamber according to the reaction conditions. The device has the advantages of high hydrogen-production reaction efficiency, high automation, easily controlled reaction speed, safe and reliable use, simple and convenient operation, and the like, and is especially suitable for the movable hydrogen supply device.

Description

A kind ofly use the device that sodium borohydride prepares hydrogen

Technical field

The utility model relates to the preparation of hydrogen, particularly relates to a kind of device that sodium borohydride prepares hydrogen of using.The utility model is used to hydrogen fuel cell that the portable hydrogen source of high-energy-density is provided, and belongs to new energy technology development, has realized the automatic control of sodium borohydride hydrogen manufacturing.

Background technology

The utilization of current hydrogen-oxygen fuel cell exploitation, the particularly exploitation of Proton Exchange Membrane Fuel Cells has become the new millennium to capture the cutting edge technology field of energy dilemma and environmental pollution in the world.The Application Areas of the sophisticated relatively proton exchange film fuel battery system of excellent performance and technology is wide and demand is big, is subjected to people's extensive concern always.But the major issue that the fuel cell large-scale application be badly in need of to solve is exactly how to provide hydrogen source efficiently and safely for fuel cell.

The supply of hydrogen fuel can be adopted direct storage hydrogen and indirect hydrogen supply dual mode in the proton membrane fuel battery system at present.Directly hydrogen storage method comprises that gaseous state high-pressure storage, the solid-state storage of alloy and low temperature liquid store three kinds of modes, but have all that energy storage density is low, accumulator system is bulky, hydrogen storage and the uneasy congruent problem of transportation.What hydrogen supply research at present was more indirectly is reformation hydrogen production under catalyst action with methyl alcohol or ethanol, but there is CO too high levels in the reformed gas, need exploitation dedicated separation film purified hydrogen, that is that all right is ripe for current separatory membrane technology, the cost costliness is not suitable for being applied to portable small power fuel cell system.

Sodium borohydride is the crystalline powder of a kind of white, and hydrogen storage capability own is 10.8% (massfraction).Sodium borohydride is a kind of strong reductant, at room temperature contacts with water and can react generation hydrogen, and reaction formula is: NaBH ₄+ 2H ₂O → 4H ₂+ NaBO ₂Adopt the method advantage of borohydride hydrolytic hydrogen production to be: 1) the efficiency of storage height of hydrogen; 2) hydrogen purity height in the product gas does not need special refining plant; 3) accumulating is easy, safety non-pollution.

The utility model content

The purpose of this utility model is the shortcoming that overcomes prior art, provide a kind of level of automation height, safe in utilization, delivery is convenient, hydrogen purity is high and the application sodium borohydride of environmental protection prepares the device of hydrogen.

The purpose of this utility model realizes by following technical proposals:

A kind ofly use the device that sodium borohydride prepares hydrogen, comprise reaction unit and control device, the sodium borohydride solution case of described reaction unit is connected with the small power hydro-pump; The small power hydro-pump is connected with reaction chamber by one of high-speed electromagnetic valve, check valve and joint flange successively; High-speed electromagnetic valve also is connected with the sodium borohydride solution case by pipeline; Reaction chamber also is connected with threeway; The upper end of threeway is connected with scatterer by pipeline; Scatterer is connected with gas-liquid separator by pipeline; Gas-liquid separator is connected with exhausted bath box by three of check valve, and gas-liquid separator also is connected with the solid acid box by pipeline; The solid acid box is connected with storage hydrogen case by four of reducing valve and check valve; Storage hydrogen case is connected with speed-regulating valve;

The microprocessing unit of described control device is electrically connected with analog to digital conversion circuit, keyboard, LCD display, scatterer and isolated drive circuit respectively; Analog to digital conversion circuit is electrically connected with three of two and thermistor of one of two and thermistor of one of hydrogen gas sensor, pressure transmitter and pressure transmitter, thermistor respectively; Isolated drive circuit is electrically connected with small power hydro-pump and high-speed electromagnetic valve respectively; One of one of pressure transmitter, thermistor and hydrogen gas sensor are installed on the reaction chamber; Three of two and thermistor of thermistor is installed in the import and export end of scatterer respectively; Two of pressure transmitter is located on the storage hydrogen case.

Capillary jet pipe and catalyst-assembly are housed in the described reaction chamber, have processed the spout of diameter on the capillary jet pipe, make solution be ejected on the catalyst-assembly uniformly less than 0.5mm; Catalyst-assembly adopts on the support of the catalyst of chemical deposition attached to porous carrier materials; Catalyst-assembly is made membrane-like and is covered on reaction chamber wall; Catalyzer is metal or bimetal, and support of the catalyst is resin, activated carbon or metal oxide; Screen cloth is equipped with in the junction of reaction chamber and threeway.

Described microprocessor unit is a SST89E564RD type micro-chip.Described high-speed electromagnetic valve can be selected corrosion resistant two-position three way magnetic valve for use.The lower end of described threeway is connected with exhausted bath box by two of check valve.

Advantage that the utlity model has and positively effect: (1) the utility model plant automation degree height, simple to operation; (2) the utility model device is safe in utilization, and delivery is convenient; (3) carbon containing and nitrogenous obnoxious flavour are not discharged in the use of the utility model device, and be pollution-free; (4) hydrogen purity height in the utility model product gas does not need special refining plant, can not cause poisoning of electrode catalyst of fuel cell; (5) the utility model energy utilization rate height does not need external energy just can come out the hydrogen release in sodium borohydride and a part of water in the reaction process.

Description of drawings

Fig. 1 is the structural representation that application sodium borohydride of the present utility model prepares the device of hydrogen;

Fig. 2 is a control device structural representation of the present utility model;

Fig. 3 is a sodium borohydride hydrogen production reaction method flow skeleton diagram of the present utility model;

Fig. 4 is pressure P ID Principles of Regulation figure of the present utility model;

Fig. 5 is that hydrogen of the present utility model detects the interrupt routine flow diagram.

Embodiment

The utility model is described in further detail below in conjunction with drawings and Examples, but embodiment of the present utility model is not limited thereto.

As shown in Figure 1, 2, use the device that sodium borohydride prepares hydrogen and comprise reaction unit and control device.Reaction unit comprises solid acid box 1, gas-liquid separator 2, scatterer 3, reaction chamber 6, joint flange 8, high-speed electromagnetic valve 11, small power hydro-pump 12, sodium borohydride solution case 13, exhausted bath box 14, storage hydrogen case 15, speed-regulating valve 16, threeway 18 and reducing valve 24, and its mutual alignment and annexation are: sodium borohydride solution case 13 is connected with small power hydro-pump 12; Small power hydro-pump 12 is connected with reaction chamber 6 by one of high-speed electromagnetic valve 11, check valve 10 and joint flange 8 successively; High-speed electromagnetic valve 11 also is connected with sodium borohydride solution case 13 by pipeline; Reaction chamber 6 also is connected with threeway 18; The lower end of threeway 18 is connected with exhausted bath box 14 by 2 17 of check valve; The upper end of threeway 18 is connected with scatterer 3 by pipeline; Scatterer 3 is connected with gas-liquid separator 2 by pipeline; Gas-liquid separator 2 is connected with exhausted bath box 14 by 3 21 of check valve, and gas-liquid separator 2 also is connected with solid acid box 1 by pipeline; Solid acid box 1 is connected with storage hydrogen case 15 by 4 23 of reducing valve 24 and check valve; Storage hydrogen case 15 is connected with speed-regulating valve 16.

Control device comprises hydrogen gas sensor 4, pressure transmitter, thermistor, microprocessing unit 26 and small-sized hydraulic pump 12, high-speed electromagnetic valve 11, scatterer 3, LCD display 29, keyboard 28, isolated drive circuit 27 and analog to digital conversion circuit 25.Wherein, isolated drive circuit 27 and analog to digital conversion circuit 25 and microprocessing unit 26 integrated circuit cards form switchboard 9.Pressure transmitter comprises 2 22 of one of pressure transmitter 7 and pressure transmitter, thermistor comprise one of thermistor 5, thermistor 2 19 and thermistor 3 20; One of one of pressure transmitter of installing on the reaction chamber 67, thermistor 5 and hydrogen gas sensor 4; 3 20 of 2 19 and thermistor of the thermistor that the import and export end of scatterer 3 is installed respectively; Storage hydrogen case 15 is provided with 2 22 of pressure transmitter.Analog to digital conversion circuit 25 is electrically connected with hydrogen gas sensor 4, pressure transmitter and thermistor respectively; Microprocessing unit 26 is electrically connected with analog to digital conversion circuit 25, keyboard 28, LCD display 29, scatterer 3 (fan and radiator element) and isolated drive circuit 27 respectively; Isolated drive circuit 27 is electrically connected with small power hydro-pump 12 and high-speed electromagnetic valve 11 respectively.

The capillary jet pipe is housed in the reaction chamber 6, has processed the spout of diameter on the capillary jet pipe, thereby make solution be ejected on the catalyzer uniformly less than 0.5mm; Catalyzer adopts on the support of the catalyst of chemical deposition attached to porous carrier materials and is prepared from; Catalyzer is metal or bimetal, and as Pt, Rh, Ru, Pd, Ni, Fe, Co, Ni, Cu, PtRu (alloy that refers to Pt metal and Ru metal) etc., support of the catalyst is resin, activated carbon or metal oxide, as LiCoO ₂, CoO, TiO ₂, Co ₃O ₄Deng; Support of the catalyst is made membrane-like and is covered on reaction chamber wall; Screen cloth is equipped with in the junction of reaction chamber and threeway, so that stagnant catalyst.Gas-liquid separator separates with liquid the gas of reaction product.Threeway 18 is a kind of joints that are provided with three interfaces, also can be used as the initial gross separation of gas and liquid in this example.

Gas-liquid separator 2 can be selected the gas-liquid separator of corrosion resistant material for use; Scatterer 3 can be selected the aluminium cpu heat for use; Solid acid box, reaction chamber, joint flange, sodium borohydride solution case, exhausted bath box, storage hydrogen case, threeway can adopt stainless material to form with the processing and manufacturing of common machine working method; It is the check valve of 0.1MPa that check valve can adopt opening pressure; High-speed electromagnetic valve can be selected corrosion resistant two-position three way magnetic valve for use; The small power hydro-pump can adopt the hydro-pump of 12V-3W; It is the reducing valve of 0.1-0.7MPa that reducing valve can adopt pressure relief ranges.Microprocessor unit 26 can be selected the SST89E564RD micro-chip for use; This micro-chip has advantages such as the storage space of 5 passage pwm signals output, 64K Flash and online programming ability, use its PWM module can make things convenient for the voltage of regulating small power hydro-pump 12 exactly, the storage of program and data can be satisfied in the Flash space of 64K, and online programming makes system debug convenient and swift.System is started working and determine hydrogen manufacturing speed by keyboard 28 input.

The useful range of pressure transmitter (one of pressure transmitter 7 and pressure transmitter 2 22) is 0.1-0.5Mpa, the useful range of thermistor (2 19 and thermistor of one of thermistor 5, thermistor 3 20) is-30 ℃-100 ℃, hydrogen gas sensor 4 sensitivity are 20ppm-200ppm, isolated drive circuit 27 act as elimination undesired signal and driving sensor and pump; Analog to digital conversion circuit 25 carries out mould/number and D/A switch, realizes the communication between microprocessing unit 26 and the extraneous components and parts.One of pressure transmitter 7 is gathered the pressure signal in the reaction chamber 6 and has been fed back to integrated in the switchboard 9 of circuit such as microprocessing unit 26, thereby regulates the voltage of small power hydro-pump 12 or the cycle switch time Controlling System hydrogen manufacturing speed of high-speed electromagnetic valve 11; One of thermistor 5 can measure reaction chamber temperature; 2 19 of thermistor can measure the temperature of scatterer import; 3 20 of thermistor can measure the temperature of radiator outlet; Hydrogen gas sensor 4 (for highly sensitive, can anti-water vapor, the industrial hydrogen gas sensor of interference gas such as CO) can measure the outer density of hydrogen of reaction chamber 6, and control system alarm or shutdown when the hydrogen gas leakage phenomenon is arranged; Relevant informations such as explicit user set(ting)value, pressure signal, temperature signal and hydrogen manufacturing speed in the LCD display.

During use, in the sodium borohydride solution case, add sodium borohydride aqueous solution, controller unit is provided with the pressure and the temperature variation parameter of reaction chamber reaction earlier, reaction chamber density of hydrogen parameter, scatterer advances, the pressure parameter of temperature out parameter and storage hydrogen case, controller unit calculates according to the concentration of sodium borohydride solution and control solution add-on, when the reaction chamber internal pressure is lower than when parameter value is set, open the small-sized hydraulic pump by switchboard, extracting sodium borohydride solution adds in the reaction chamber through high-speed electromagnetic valve, make-and-break time by the control high-speed electromagnetic valve is finely tuned adding solution amount, solution reacts generation hydrogen in reaction chamber, hydrogen is through gas-liquid separator separates steam, separate alkaline matter through the solid acid box, enter storage hydrogen case through reducing valve again, regulate the fueling battery by speed-regulating valve at last and use; One of one of pressure transmitter of installing on the reaction chamber 7, thermistor 5 and hydrogen gas sensor 4 are sampled, and compare with set(ting)value, utilize microprocessing unit 26 can accurately regulate interior make-and-break time of high-speed electromagnetic valve unit time, too high or when the hydrogen gas leakage phenomenon was arranged, control device can be reported to the police or shut down when temperature; The capillary jet pipe is housed in the reaction chamber, has processed the spout of diameter on the capillary jet pipe, thereby make solution be ejected on the catalyzer uniformly less than 0.5mm; Screen cloth is equipped with in the junction of reaction chamber and threeway, so that stagnant catalyst; Threeway separates with liquid the gas of reaction product; The import and export of scatterer installed thermistor 2 19 and thermistor 3 20, thereby in time feedback temperature information is to switchboard 9, when temperature was too high, control device can be reported to the police or shut down; The chemical molecular sieve is housed, as Al in the solid acid box ₂O ₃Deng solid acid, thereby gas is purified; When storing up the hypertonia of hydrogen case 15,2 22 power supplys of pressure transmitter through switchboard switching hydro-pump; Switchboard can be provided with system pressure and temperature variation parameter as required, calculate and the control add-on by the concentration of sodium borohydride solution, and by the feedback pressure and temperature signal regulate the voltage of small-sized hydraulic pump and the make-and-break time of high-speed electromagnetic valve automatically, thereby accurately control the pressure and temperature signal of reactive system.

The program of the utility model device adopts the KEIL IDE, and program comprises that pressure P ID regulates program, hydrogen detects interrupt routine, temperature detection program.

Fig. 3 is a sodium borohydride hydrogen production reaction method flow skeleton diagram of the present utility model, and the system boot initialize by keyboard operation setting device hydrogen supply speed, and is presented on the LCD.Microprocessing unit 26 calculates the hydrogen outlet pressure value P simultaneously according to voltage and the power that calculation of parameter goes out the small-sized hydraulic pump is set _SETAnd be shown on the LCD.Parameter is provided with, and reaction chamber internal reaction pressure is set to 0.1Mpa-0.2Mpa, and temperature is set in 100 ℃, the outer density of hydrogen of reaction chamber is set to 4%, the scatterer inlet temperature is set in 70 ℃, and outlet tank temperature is set in 40 ℃, and the pressure in the storage hydrogen case is 0.1Mpa.After demonstration is finished, controller unit calculates according to the concentration of sodium borohydride solution and control solution add-on, the small-sized hydraulic pump work, solution is sprayed into catalyst surface reaction hydrogen manufacturing, the system acquisition pressure signal, call pressure regulon program, secondary feedback (coarse adjustment and fine setting) control hydrogen manufacturing speed is called hydrogen simultaneously and is interrupted trace routine density of hydrogen in the monitoring device constantly.Utilize microprocessor unit 26 timers to interrupt detecting and have or not the hydrogen gas leakage phenomenon, density of hydrogen in the timed interval detection system of setting according to timer is if concentration is greater than the safety value of setting then disconnect pumping source and hydrogen production reaction is stopped and warning on LCD.

In this device, system mainly comes the hydrogen manufacturing speed of Controlling System as feedback with pressure signal, the error that makes the hydrogen manufacturing speed that itself and user set is in allowed band, pressure is regulated fundamental diagram as shown in Figure 4: the adjusting of hydrogen manufacturing speed is divided into two-stage (secondary feedback, coarse adjustment and fine setting), the first step is coarse adjustment, is the hydrogen manufacturing speed of utilizing the user the to set power that calculates pump (thereby calculate the voltage of pump) and hydrogen pressure P _SETThereby, but make the interior hydrogen pressure P of reaction chamber greatly and set the hydrogen pressure P that calculates according to the user owing to the voltage of regulating pump may make the interior flow error of unit time of reaction raw materials _SETError is bigger, thus when regulating the magnitude of voltage of direct current hydro-pump in reaction chamber hydrogen pressure P greater than set the hydrogen pressure P that calculates according to the user _SET, and error is just passable when being not more than setting range, that is: 0＜P≤P _SETThe second stage is fine setting, be equally utilize in the reaction chamber hydrogen pressure P as feedback quantity with set the hydrogen pressure P that calculates according to the user _SETRelatively, but do not regulate the voltage of hydro-pump but regulate switching time in the high-speed electromagnetic valve sampling period, and in microprocessing unit 26, write relevant pid algorithm.Pid algorithm control is as follows:

$u\left(k\right)=K_{p}e\left(k\right)+K_i\underset{j=0}{\overset{k}{\mathrm{\Σ}}}e\left(j\right)+K_d[e\left(k\right)-e(k-1)]---\left(1\right)$

$T\left(k\right)=\frac{u\left(k\right)\·T_s}{P_1}---\left(2\right)$

$T\left(k\right)=\frac{T_s}{P_1}\{K_{p}e\left(k\right)+K_i\underset{j=0}{\overset{k}{\mathrm{\Σ}}}e\left(j\right)+K_d[e\left(k\right)-e(k-1)]\}---\left(3\right)$

U in the formula 1 (k) is a hydrogen pressure value of using output in the reaction chamber, and e (k) is the pressure error in k sampling period, that is: e (k)=P _SET-P, K _p, K _i, K _dBe respectively rate constant, integration constant and derivative constant, Ts is the sampling period, P ₁Be the chamber pressure after the first step hydrogen manufacturing speed setting, the time that T (k) should close for high-speed electromagnetic valve in the sampling period (is NaBH ₄Solution flows to the time of reaction chamber) because u (k) has the relation of formula 2 with T (k), so can get formula (3).

In this device, because hydrogen is inflammable gas, and the hydrogen rate that generates in the reaction chamber is than very fast, in case when being arranged, the hydrogen gas leakage phenomenon must in time find, otherwise may cause danger, and therefore, adopt hydrogen to detect interrupt routine.Hydrogen detects the interrupt routine schema as shown in Figure 5: the utility model utilizes timer (micro-chip SST89E564RD inside carries timer) to interrupt detecting having or not the hydrogen gas leakage phenomenon, density of hydrogen in the timed interval detection system of setting according to timer, if thereby concentration greater than the safety value of setting then disconnect pumping source and hydrogen production reaction is stopped and warning prompting customer inspection system on LCD.

Embodiment 1: according to sodium borohydride device for producing hydrogen shown in Figure 1, employing concentration is 10% sodium borohydride solution, the flow velocity of small power hydro-pump 12 is 30ml/min, the initial setting make-and-break time ratio of high-speed electromagnetic valve 11 is 1: 6, the top hole pressure that reducing valve 24 is set is 0.1MPa, pressure transmitter 7 collects the interior pressure signal of reaction chamber and signal feedback is arrived switchboard 9, and the pressure 0.1-0.2Mpa that sets with the user compares, thereby regulates the make-and-break time ratio of high-speed electromagnetic valve.Hydrogen gas sensor 4 is gathered the outer density of hydrogen signal of reaction chamber and signal feedback is arrived switchboard, finds concentration not greater than the safety value of setting 4%, and system works is normal.3 20 of 2 19 and thermistor of thermistor gathered the hydrogen temperature signal of scatterer import and export respectively, and inlet temperature is not higher than 70 ℃, and temperature out is not higher than 40 ℃, system's works better.Hydrogen uses from storage hydrogen case fueling battery through speed-regulating valve, and the flow velocity of hydrogen is about 1L/min.

Claims (5)

1, a kind ofly use the device that sodium borohydride prepares hydrogen, comprise reaction unit and control device, it is characterized in that: the sodium borohydride solution case of described reaction unit is connected with the small power hydro-pump; The small power hydro-pump is connected with reaction chamber by one of high-speed electromagnetic valve, check valve and joint flange successively; High-speed electromagnetic valve also is connected with the sodium borohydride solution case by pipeline; Reaction chamber also is connected with threeway; The upper end of threeway is connected with scatterer by pipeline; Scatterer is connected with gas-liquid separator by pipeline; Gas-liquid separator is connected with exhausted bath box by three of check valve, and gas-liquid separator also is connected with the solid acid box by pipeline; The solid acid box is connected with storage hydrogen case by four of reducing valve and check valve; Storage hydrogen case is connected with speed-regulating valve;

The microprocessing unit of described control device is electrically connected with analog to digital conversion circuit, keyboard, LCD display, scatterer and isolated drive circuit respectively; Analog to digital conversion circuit is electrically connected with three of two and thermistor of one of two and thermistor of one of hydrogen gas sensor, pressure transmitter and pressure transmitter, thermistor respectively; Isolated drive circuit is electrically connected with small power hydro-pump and high-speed electromagnetic valve respectively; One of one of pressure transmitter, thermistor and hydrogen gas sensor are installed on the reaction chamber; Three of two and thermistor of thermistor is installed in the import and export end of scatterer respectively; Two of pressure transmitter is located on the storage hydrogen case.

2, application sodium borohydride according to claim 1 prepares the device of hydrogen, it is characterized in that, capillary jet pipe and catalyst-assembly are housed in the described reaction chamber, have processed the spout of diameter on the capillary jet pipe, make solution be ejected on the catalyst-assembly uniformly less than 0.5mm; Catalyst-assembly adopts on the support of the catalyst of chemical deposition attached to porous carrier materials; Catalyst-assembly is made membrane-like and is covered on reaction chamber wall; Catalyzer is metal or bimetal, and support of the catalyst is resin, activated carbon or metal oxide; Screen cloth is equipped with in the junction of reaction chamber and threeway.

3, application sodium borohydride according to claim 1 prepares the device of hydrogen, it is characterized in that, described microprocessor unit is a SST89E564RD type micro-chip.

4, application sodium borohydride according to claim 1 prepares the device of hydrogen, it is characterized in that, described high-speed electromagnetic valve can be selected corrosion resistant two-position three way magnetic valve for use.

5, application sodium borohydride according to claim 1 prepares the device of hydrogen, it is characterized in that, the lower end of described threeway is connected with exhausted bath box by two of check valve.

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