CN101407341B - Method for reclaiming and recycling waste nickel-cadmium battery - Google Patents

Abstract

The invention provides a resource recycling production method of waste nickel cadmium batteries, relating to a physical separation method for the various components of the waste nickel cadmium battery, including a shell, an electrolyte, a positive plate, a negative electrode material and a negative electrode electricity collecting body perforated steel ribbon, and a recycling scheme of a pure electrode material obtained by separation; and the method provides a low-cost way for resource recycling production of the waste nickel cadmium battery. Concretely, all the components of the waste nickelcadmium battery are separated by the physical method at first, then the obtained positive plate and negative electrode powder are chemically treated to prepare new positive electrode material Ni(OH)2and negative electrode material Cd(OH)2 of the nickel cadmium battery, and then the commercialized nickel cadmium battery production line is used for producing new nickel cadmium batteries.

Description

A kind of method for reclaiming and recycling of abandoned nickel and cadmium cell

Technical field

The present invention relates to a class uses physical method the various compositions of abandoned nickel and cadmium cell, the physical separation method that comprises shell, electrolyte, positive electrode, negative material, collector body perforated steel ribbon, and positive electrode that separate to obtain and negative material utilize scheme again, for the resource of abandoned nickel and cadmium cell and the circulation production of nickel-cadmium cell provide a route cheaply.

Background technology

NI-G (Ni-Cd) battery claims that also ickel-cadmium cell is a kind of quite ripe secondary cell.It has characteristics such as long service life, power output is big, the charging interval is short, mainly is used to the electric tool industry at present.Under the powerful market demand drove, China had become the maximum ickel-cadmium cell producing country in the whole world, produces 1000000000 of nickel-cadmium cells per year.Wherein be used for the supporting nickel-cadmium cell of electric tool and be about 800,000,000, estimate year 8,600 tons of cadmiums of consumption, 6,240 tons in nickel, relate to more than associated production practitioner 10,000 people.

Nickel-cadmium cell has a fatal problem, is exactly the cadmium that wherein contains high environmental toxicity.The cadmium of high concentration can residual and enrichment in plant and organism, finally enters human body by food chain, jeopardizes human health.Cadmium poisoning can cause injury of kidney, upset,gastro-intestinal and painstaking effort dysfunction and Itai-itai diseases etc.As consuming one of maximum manufacturing industry of cadmium, all there is the hidden danger that cadmium pollution takes place in ickel-cadmium cell in raw material production, battery production, each link of using, abandoning.Therefore how to reduce or eliminates cadmium pollution risk that ickel-cadmium cell may cause and become the industrial policy that comprises Chinese countries in the world and the great focus of environmental protection policy.For example, clearly classified as restricted project by the national development and the reform committee at China's ickel-cadmium cell; In February, 2008, State Environmental Protection Administration will list " the high environmental risk product of high pollution register " in except that the ickel-cadmium cell military, aviation and the train special use again, and the refund of suggestion cancelling.

The scheme of eliminating the environmental pollution risk that the nickel-cadmium cell industry may bring is nothing more than two kinds of schemes: a kind of substitute that is to use nickel-cadmium cell, fundamentally eliminate the production of nickel-cadmium cell; A kind of is to produce and using in each link and go all out to fight the floods, and never allows cadmium element to flow into environment.Comparatively speaking, preceding a kind of scheme is the direction that present industrial circle is made great efforts, but for market, before any one problem of new product purchase cost, use cost, safety in utilization or the like can not solve, old product still has certain market, is difficult to eliminate at once; A kind of scheme in back, for manufacturer, be to stop toxic metals such as cadmium to enter environment under the production system of strictness, but in the consumption link, particularly after arriving useful life, how to reclaim by nickel-cadmium cell, do not abandoned arbitrarily by the consumer, and how high efficiente callback utilizing again, also is a very large challenge.We think, study a kind of high efficiente callback and resource approach, make be engaged in reclaim and the enterprise of resource lucrative, may be the effective way of tackling above-mentioned challenge.

The recycling problem of nickel-cadmium cell involves a large amount of technology, economy and environmental protection factor, if method is improper, must cause problem low in economic efficiency, that also aggravate its secondary environmental pollution thus.The main component of nickel-cadmium cell has iron (coming from shell, negative current collector), metallic nickel and nickel hydroxide (coming from positive plate), cadmium metal and cadmium hydroxide (coming from negative plate), cobalt hydroxide (additive for electrode), also has alkaline electrolyte and a spot of plastic components.

Existing nickel-cadmium cell recovery scheme roughly can be divided into two classes: the first kind is the wet method extractive technique, comprises that whole fragmentation, acidleach are got, the steps such as separation one by one of element, is purpose to obtain respective element and compound thereof.This method major defect is the production cost height, the risk height of secondary pollution.CN1752232, CN1949584 disclose a kind of like this method; Second class is a dry metallurgical technology, utilizes the low melting point characteristic of cadmium, uses vacuum distillation method to extract cadmium metal, and then manages to reclaim metallic nickel, ferrous metal or their alloy or compound or the like.For example, Chinese invention patent CN1357938, CN101220412 disclose a kind of like this method, and its product is cadmium metal and ferrite or iron-nickel alloy.

The present invention has adopted the third scheme, promptly at first uses the method for machinery that waste nickel hydrogen battery is separated into shell, positive pole, negative pole powder, perforated steel ribbon and barrier film, is aided with suitable chemical treatment then to obtain can be used to produce the raw material of new nickel-cadmium cell.This method energy consumption is low, simple to operate, and the risk of secondary pollution is much smaller, has high economic benefit and social benefit, for the resource of abandoned nickel and cadmium cell and the circulation production of nickel-cadmium cell provide a route cheaply.

Summary of the invention

Technical problem: the method for reclaiming and recycling that the purpose of this invention is to provide a kind of abandoned nickel and cadmium cell.Wherein comprise the Physical Separation Technology that the various component separation of abandoned nickel and cadmium cell are come, and be the chemical regeneration technology that raw material production is used for new electrode material with the both positive and negative polarity composition that separation obtains.

Technical scheme: the method for reclaiming and recycling of a kind of abandoned nickel and cadmium cell of the present invention is:

At first all the components with abandoned nickel and cadmium cell all passes through physical method for separation, and positive plate that separation is obtained and negative pole powder carry out chemical treatment respectively with regeneration nickel-cadmium cell positive electrode Ni (OH) then ₂With negative material Cd (OH) ₂, re-use the new nickel-cadmium cell of business-like nickel-cadmium cell production line production.Wherein said physical separation method is to use following steps that abandoned nickel and cadmium cell is decomposed into metal shell, electrolyte, positive plate, CdO and perforation and just be with:

1) uses mechanical means the refuse battery fragmentation, metal shell and battery material are separated;

2) water washes out the electrolyte of battery, and filters out, and obtains all solids composition of electrolyte and battery, and electrolyte can be directly used in the production of positive electrode;

3) the battery solid constituent section of removing electrolyte, under 200～350 ℃ of air atmospheres, handled 20～60 minutes, with the burning-off diaphragm material, in this process, negative electrode active composition Cd (OH) ₂Can dehydration form CdO;

4) with magnetic separator positive plate, negative plate, the negative pole powder CdO that drops are separated, the CdO powder that still is attached on the negative plate uses the method for vibration to make it thoroughly to break away from the negative electrode collector perforated steel ribbon, makes the two separation by screening then; The CdO that CdO and step 3 are obtained merges.

Described regeneration nickel-cadmium cell positive electrode Ni (OH) ₂With negative material Cd (OH) ₂Method be:

1) positive plate that above-mentioned magnetic separation is obtained directly is dissolved in watery hydrochloric acid, can obtain Ni (OH) with alkali metal hydroxide or ammonia precipitation process again ₂

2) CdO that obtains of physical separation is dissolved in watery hydrochloric acid, after removing impurity, obtains Cd (OH) with alkali precipitation again ₂

Can produce the nickel-cadmium cell (nickel hydroxide has residue) of same specification by existing nickel-cadmium cell production method, realize the circulation production of Ni-MH battery.

Beneficial effect: what the present invention relates to is a kind of physical separation with the various compositions of abandoned nickel and cadmium cell, and the method that is used for the electrode material of new battery production from the battery component production that separation obtains.This method has farthest kept the availability of battery material, and minimum degree ground produces low value-added byproduct, is a kind of green production technology that meets the recycling economy principle.

Description of drawings

Fig. 1 is the physical separation schematic flow sheet of waste nickel hydrogen battery.

Embodiment

1. the Mechanical Crushing of battery:

Existing nickel-cadmium cell generally adopts anode and cathode active materials to be coated in respectively on nickel foam and the perforated steel ribbon, and uses barrier film to make electrode material break away from the directly method of contact.In order to make reprocessing become more or less freely, the fragmentation of battery should be used comparatively gentle mode.In the laboratory, can use hacksaw that the battery case that bleeds off remaining capacity is cut; Industrial, adopt a kind of machinery that can peel off the plastics of the battery that bleeds off remaining capacity and metal shell, thereby the content of the metal shell of battery with battery separated.

2. electrolyte and other solids content separates

The water that use has removed carbon dioxide can come out the electrolyte that contains in the cell contents, by filter operation electrolyte and other solid matter is separated, and hereinafter this filtrate is called electrolyte solution.

3. the calcination processing of electrode and the removal of barrier film

The electrode of flush away electrolyte is cut into 1cm behind the square fragment of 5cm, because battery diaphragm is difficult to remove, is a simple method with its burning-off.Usually, under the temperature about 200～350 degree, handle and to remove fully less than 60 minutes.At this moment, the Cd on the negative plate (OH) ₂Can dehydration form CdO, and because come off inadequately with collector perforated steel ribbon adhesive force.

4. positive plate, negative electrode active material separate with the perforated steel ribbon sheet

Use concentration equipment to separate top three compositions fully, because perforated steel ribbon is subject to magnetic field suction most, positive plate takes second place, and CdO is not attracted fully.Be attached on perforation just with on the part negative material can by vibrations desorption, can make the two separation by simple screening.Two parts CdO powder is merged.

5. the processing of positive plate and new positive electrode is synthetic

Usually the positive plate of nickel-cadmium cell is that nickel hydroxide is attached on the nickel foam and forms, and generally they are difficult to separate.Can obtain to be used for the nickel hydroxide of new battery production by following two kinds of methods: (1) handles positive plate with an amount of watery hydrochloric acid, and positive plate all changes into NiCl as a result ₂Solution, and emit some hydrogen.Remove by filter undissolvable binding agent etc., analyze the content of nickel in the filtrate, and be benchmark, add the ratio that different slaines is adjusted each element, under nitrogen protection, add positive electrode α or β-Ni (OH) that the alkali co-precipitation obtains needs with it ₂(2) with the oxidation under the condition that oxygen exists of part positive plate, to obtain Ni ₂O ₃With this Ni ₂O ₃With remaining positive plate contain other must the aqueous solution of ion in coprocessing, promptly obtain the positive electrode α or the β-Ni (OH) that need ₂

6. negative material Cd (OH) ₂Regeneration

CdO that the 4th step obtained and aqueous alkali reaction can obtain being directly used in the Cd (OH) of battery production ₂Nickel-cadmium cell through repeatedly circulation may contain more impurity, can influence Cd (OH) ₂Performance.Therefore, CdO is dissolved in acid, uses alkali precipitation then, can obtain satisfactory Cd (OH) through removal of impurities ₂

Claims (2)

1. the method for reclaiming and recycling of an abandoned nickel and cadmium cell is characterized in that at first all the components of abandoned nickel and cadmium cell is separated, and positive plate that separation is obtained and negative pole powder carry out chemical treatment respectively with regeneration nickel-cadmium cell positive electrode Ni (OH) then ₂With negative material Cd (OH) ₂, re-use the new nickel-cadmium cell of business-like nickel-cadmium cell production line production; Wherein said separation method is to use following steps that abandoned nickel and cadmium cell is decomposed into metal shell, electrolyte, positive plate, CdO and perforation and just be with:

1) uses mechanical means the refuse battery fragmentation, metal shell and battery material are separated;

2) water washes out the electrolyte of battery, and filters out, and obtains all solids composition of electrolyte and battery, and electrolyte is directly used in the production of positive electrode;

3) the battery solid constituent section of removing electrolyte, under 200～350 ℃ of air atmospheres, handled 20～60 minutes, with the burning-off diaphragm material, in this process, negative electrode active composition Cd (OH) ₂Can dehydration form CdO;

4) with magnetic separator positive plate, negative plate, the negative pole powder CdO that drops are separated, the CdO powder that still is attached on the negative plate uses the method for vibration to make it thoroughly to break away from the negative electrode collector perforated steel ribbon, makes the two separation by screening then; The CdO that CdO and step 3 are obtained merges.

2. the method for reclaiming and recycling of an a kind of abandoned nickel and cadmium cell as claimed in claim 1 is characterized in that described regeneration nickel-cadmium cell positive electrode Ni (OH) ₂With negative material Cd (OH) ₂Method be:

1) positive plate that above-mentioned magnetic separation is obtained directly is dissolved in watery hydrochloric acid, can obtain Ni (OH) with alkali metal hydroxide or ammonia precipitation process again ₂

2) separate the CdO that obtains and be dissolved in watery hydrochloric acid, after removing impurity, obtain Cd (OH) with alkali precipitation again ₂

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