CN1306996C

CN1306996C - A kind of adsorbent/foam aluminum composite adsorption material and preparation method thereof

Info

Publication number: CN1306996C
Application number: CNB2004100140234A
Authority: CN
Inventors: 胡芃; 陈则韶; 程和法
Original assignee: University of Science and Technology of China USTC
Current assignee: University of Science and Technology of China USTC
Priority date: 2004-02-03
Filing date: 2004-02-03
Publication date: 2007-03-28
Anticipated expiration: 2024-02-03
Also published as: CN1651133A

Abstract

The present invention relates to an adsorbent / foamed aluminum compound adsorption material and a preparation method thereof, which is characterized by filling spherical zeolite or molecular sieve particles with a diameter of 3 to 6mm into a mold to 20 to 60mm in height, adding table salt particles with a diameter of less than 1mm according to the volume ratio of table salt to an adsorbent granule stack of 4:6, and uniformly filling; pressurizing, tightly prepressing, and preheating to 500 to 600 DEG C; pouring the molten aluminum into the mold according to the volume ratio of the molten aluminum to the adsorbent granule stack of 2:8, and pressurizing to 2 to 5 atm; washing to dissolute and extract salt after cooling solidification, and keeping a constant temperature of 350 DEG C for 3 hours. The prepared adsorbent/ foamed aluminum compound adsorption material with the thermal coefficient of 1 to 4 W/m. K is formed by that clearance among particles accounting for 60 to 65% of the total volume is filled with the through hole foamed aluminum accounting for 10% to 25% of the total volume; the prepared adsorbent/ foamed aluminum compound adsorption material can also form a through hole foamed aluminum structure with scarcely affected mass transfer performance and high structural strength and obviously improve the heat transfer performance of adsorbent beds.

Description

A kind of adsorbent/foamed aluminium composite adsorbing material and preparation method thereof

Technical field:

The invention belongs to the absorption type refrigerating sorbing material, particularly adsorbent/foamed aluminium composite adsorbing material and preparation method thereof.

Background technology:

Zeolite and molecular sieve are sorbing material commonly used in the absorption type refrigerating, are porous media material, and heat-conductive characteristic is low, is 0.08～0.1W/mK as the stacking bed thermal conductivity factor of zeolite granular, and this just makes, and refrigeration system is adsorbed, the desorption cycle is long, and efficient is low." the solid adsorption refrigeration meeting " held at Paris, FRA in November, 1992 (Solid Sorption Refrigeration Sym., Paris, France, 1992, Nov.:44-52) mentioned a kind of directly method of doping aluminium powder and iron powder in absorbent particles in the paper, but this method is difficult to make these high thermal conductivity coefficient materials to form continuous phase, so the effective thermal conductivity raising is not obvious.Britain's academic journal " heat recovery system and cogeneration " (Heat Recovery System ﹠amp; CHP, 1993, once proposed 13:297-300) metal foam that the copper or the nickel foil bonding of zeolite molecular sieve and plot ratio 35% are made is evenly mixed, with organic binder cemented, compression was under high pressure dried 3 hours under 1000 ℃ of high temperature then, activated at last, can significantly improve thermal conductivity factor, but this method can cause simultaneously mass tranfer coefficient significantly to reduce and complex process.A kind of " lump zeolite adsorbent with excellent heat conductivity and absorption property " that Chinese invention patent CN 1266741A proposes is compound zeolite powder and waterglass, and thermal conductivity factor only improves 3 times." solar energy journal " (1998,19:186-190) " strengthening the research of heat-conductive characteristic in the solar energy absorber " the civilian described polyaniline/zeolite compound adsorbent in, its thermal conductivity factor also only improves 2～4 times, and mass-transfer performance descends to some extent.

Summary of the invention:

The objective of the invention is to propose a kind of compound adsorbent and preparation method thereof, can when significantly improving the adsorbent heat conductivility, still keep original mass-transfer performance.

The preparation method of adsorbent of the present invention/foamed aluminium composite adsorbing material adopts THROUGH METHOD; It is characterized in that: spherical zeolite granular or the sieve particle of diameter 3～6mm are filled in the mould to 20～60mm height; the salt particle that adds diameter＜1mm in salt and 4: 6 ratio of absorbent particles heap volume ratio; the absorbent particles gap is filled evenly; being forced into 2～3atm compresses in advance; and be preheated to 500～600 ℃; in molten aluminum and 2: 8 ratio of absorbent particles heap volume ratio molten aluminum is poured into mould then; and be forced into 2～5atm; take out washing after to be cooled the solidifying salt particle dissolves is wherein washed out, promptly obtained adsorbent/foamed aluminium composite adsorbing material in 3 hours at 350 ℃ of constant temperature at last.

Adsorbent of the present invention/foamed aluminium composite adsorbing material; it is characterized in that: be made up of the fine-crystal spume aluminium alloy that accounts for volume fraction 10%～20% of filling in the zeolite granular that accounts for volume fraction 60%～65% or sieve particle and the gap thereof, adopting the stable state flat band method to measure its thermal conductivity factor is 1～4W/mK.

Because compound adsorbent preparation method of the present invention uses the spherical adsorbent paricles gap of diameter less than the particles filled diameter 3～6mm of the salt of 1mm, and pressurized treatments, the salt particle easily forms continuous phase, original salt particle position just forms netted open-end hole in water-washing process like this, reduced the use amount of metallic aluminium on the one hand, reduced the harmful effect that the metallic aluminium thermal capacitance lags behind to heat of adsorption, absorbent particles for inside provides unimpeded mass transfer channel simultaneously, makes the adsorbent mass-transfer performance influenced hardly.Metallic aluminium volume contraction when solidifying cooling understands nature and the absorbent particles combination is tight, therefore need not to add curing agent, just can reduce the heat transfer resistance between metal and the absorbent particles, also can overcome simultaneously and stop up the adsorbent surface micropore after using curing agent, reduce the shortcoming of absorption property.Metallic aluminium is that continuous phase distributes between the absorbent particles space, can obviously improve heat conductivility, than molecular sieve with zeolite granular is stacking bed exceeds tens times.The mechanical property excellence of foamed aluminium material can be used as the adsorbent support frame simultaneously, structural strength height, not yielding breakage.

The present invention uses the through-hole foam aluminum of volume ratio 10%～20% to be the heat transfer skeleton, composite zeolite particle or sieve particle, and the time processing moulding significantly improves its heat conductivility, and has higher mass-transfer performance, and manufacture craft is simple, and is with low cost.Can reduce the adsorption/desorption time greatly for the adsorbent refrigerator that uses zeolite or sieve adsorpting bed, improve the refrigeration machine performance.

The specific embodiment:

Embodiment 1:

Adsorbent in the present embodiment adopts spherical zeolite granular or spherical sieve particle.

With the spherical zeolite granular of diameter 3～6mm or spherical sieve particle be filled to highly in the high cylindrical die of 150mm to the 60mm height; the salt particle of pressing then about salt and absorbent particles heap volume ratio adding in 4: 6 diameter 0.5mm is filled its gap evenly; and be forced into 2～3atm and compress in advance; be preheated to 500～600 ℃ simultaneously; by molten aluminum and absorbent particles heap volume ratio 2: 8 molten aluminum is poured into mould then; and be forced into 2～5atm its seepage flow is gone in the particle voids; waiting to solidify cooling fully takes out the back; wash out after making wherein salt particle dissolves by washing; in the oven dry activation in 3 hours of 350 ℃ of following constant temperature, promptly obtain adsorbent/foamed aluminium composite adsorbing material at last.

Weigh before and after volume by measuring the gained material, the washing and according to the density calculation of salt, absorbent particles and aluminium as can be known, the adsorbent of gained/foamed aluminium composite adsorbing material is filled composition by the fine-crystal spume aluminium alloy of the occupied percent by volume 10%～20% in the gap between zeolite granular that accounts for percent by volume 60%～65% or the sieve particle.

The thermal conductivity factor that adopts the stable state flat band method to measure resulting compound adsorbent is 1～4W/mK.

Adopt the resulting compound adsorbent of the inventive method, owing to form the through-hole foam constructed of aluminium, adsorbate steam mass transfer channel is unimpeded, and mass-transfer performance is influenced hardly.

Claims

1. the preparation method of adsorbent/foamed aluminium composite adsorbing material, it is characterized in that: the sieve particle of diameter 3～6mm is filled in the mould to 20～60mm height, the salt particle that adds diameter＜1mm in salt and 4: 6 ratio of absorbent particles heap volume ratio, the absorbent particles gap is filled evenly, being forced into 2～3atm compresses in advance, and be preheated to 500～600 ℃, in molten aluminum and 2: 8 ratio of absorbent particles heap volume ratio molten aluminum is poured into mould then, and be forced into 2～5atm, the back of solidifying to be cooled is taken out washing salt particle dissolves is wherein washed out, at last 350 ℃ of constant temperature 3 hours.

2. adsorbent/foamed aluminium composite adsorbing material, it is characterized in that: be made up of the fine-crystal spume aluminium alloy that accounts for volume fraction 10%～20% of filling in sieve particle that accounts for volume fraction 60%～65% and the gap thereof, adopting the stable state flat band method to measure its thermal conductivity factor is 1～4W/mK.