EP0074755B1 - Procédé pour la récupération de sables de fonderie - Google Patents
Procédé pour la récupération de sables de fonderie Download PDFInfo
- Publication number
- EP0074755B1 EP0074755B1 EP82304595A EP82304595A EP0074755B1 EP 0074755 B1 EP0074755 B1 EP 0074755B1 EP 82304595 A EP82304595 A EP 82304595A EP 82304595 A EP82304595 A EP 82304595A EP 0074755 B1 EP0074755 B1 EP 0074755B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- sand
- energy
- binder
- reclamation
- fluid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C5/00—Machines or devices specially designed for dressing or handling the mould material so far as specially adapted for that purpose
- B22C5/10—Machines or devices specially designed for dressing or handling the mould material so far as specially adapted for that purpose by dust separating
Definitions
- This invention concerns the reclamation of foundry sands.
- Foundry sand is used with suitable binding agents for making moulds and cores for casting metal.
- Various binders both inorganic and organic, are used to bond the foundry sand and, for many years, the sand after use was discarded.
- British Patent Specification No. 1,322,864 is also concerned with the problem of sand reclamation and discloses a process in which the used foundry sand is introduced into a blast of fluid under pressure, whereby the sand is projected against lateral walls of a hermetically sealed casing to cause a matrix of the binding agent to burst releasing the sand. The product of this process is then subjected to granulometric selection to remove the fines generated by the high impact.
- British Patent Specification No. 1,505,904 discloses a process in which coated sand particles are projected in a current of gas against the interior surface of a rotating drum.
- British Patent Specification No. 2,019,274 discloses a similar process in which, again, the coated sand is projected against a. solid target.
- US Patent No 2 478 461 also discloses a process for the removal of binder from foundry sand, but appears to be mainly concerned with binders which generate a carbonaceous residue. It is suggested that this residue can be burned and the partially cleaned sand further cleaned by subjecting high velocity sand grains issuing from nozzles to severe erosive action and further suggests the provision of an abrasive-resistant lining (18).
- This specification like other referred to earlier in which targets are specified, may well introduce contaminants from the target into the sand.
- the essential problem to be overcome in the sand reclamation process is an adequate balancing of two objectives, namely the effective removal of a hard and tenacious coating and the avoidance of significant particle degradation of the clean sand particles to produce fines which are not useful in the reclaimed sand.
- the present invention provides a process which effectively balances these two objectives.
- the present invention provides a process for the reclamation of silicate binder coated foundry sand, in which the coated foundry sand is subjected to a fluid energy acceleration to remove the binder and the reclaimed sand is separated from the binder debris, characterised in that the fluid energy is imparted to the sand in a fluid energy mill to a sufficient extent to substantially remove the binder coating without causing significant disintegration of the sand particles and in which the energy imparted to the sand is less than 1,300 kilojoules per kilogramme of coated sand and in which the Reynolds Number arising from the energy-imparting jet stream does not exceed 6.5x10 4 .
- the optimal energy range was from 400 to 1,200 kilojoules per kilogramme of sand.
- This work was carried out in a microniser having a diameter of 10 cm and containing six 1.6 mm diameter inlet nozzles in the periphery of the chamber.
- the feed rate of the sand varied from 0.33 to 1.54 per second and the optimum feed rate was of the order of 1 g per second for this apparatus.
- the sand feed rate can be increased in relation to the size of the mill and air throughput.
- the specific energy imparted to the sand should be of the same order of magnitude as previously defined but applied at a commercially useful sand feed rate.
- Fluid energy or jet mills (alternatively known as Micronisers) suitable for use in the process of this invention are available from various suppliers in the market and are described in, for example, Chemical Engineering Handbook, Ed. J. H. Perry, 4th ed., McGraw Hill, p. 8-42 and 43.
- Such mills consist essentially of a chamber in which the contaminated sand is acted upon by a number of gaseous fluid jets issuing through orifices spaced around the periphery of the substantially circular chamber.
- the fluid energy imparted to the sand in the mill is determined by calculating the energy expended by the adiabatic expansion of the compressed fluid through the nozzles, and is given by:
- the specific energy input is obtained by dividing by the feedrate of sand (kg/s), i.e.
- Reynolds Number is the ratio of inertial force to the viscous force of the flowing fluid. It is a measure of the air fluid velocity in the jet stream which determines the drag force exerted on the individual particles and thus determines their acceleration and their impact velocity. Reynolds Number can be calculated on the basis of the fluid mass flowrate through a single nozzle (Q f ) of nozzle diameter, d " , viscosity
- the Reynolds Number is in the range 4.Ox10 4 to 6.4x10 4 .
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Mold Materials And Core Materials (AREA)
- Disintegrating Or Milling (AREA)
Claims (3)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB8126689 | 1981-09-03 | ||
GB8126689 | 1981-09-03 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0074755A1 EP0074755A1 (fr) | 1983-03-23 |
EP0074755B1 true EP0074755B1 (fr) | 1986-01-15 |
Family
ID=10524292
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP82304595A Expired EP0074755B1 (fr) | 1981-09-03 | 1982-09-01 | Procédé pour la récupération de sables de fonderie |
Country Status (8)
Country | Link |
---|---|
EP (1) | EP0074755B1 (fr) |
JP (1) | JPS5853346A (fr) |
AU (1) | AU542894B2 (fr) |
BR (1) | BR8205096A (fr) |
CA (1) | CA1209784A (fr) |
DE (1) | DE3268559D1 (fr) |
ES (1) | ES8308242A1 (fr) |
ZA (1) | ZA826431B (fr) |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2478461A (en) * | 1946-03-16 | 1949-08-09 | Nichols Eng & Res Corp | Apparatus and method for treating foundry sand |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3088183A (en) * | 1960-12-19 | 1963-05-07 | Simpson Herbert Corp | Apparatus for treating granular material |
DE2408981C3 (de) * | 1974-02-25 | 1979-11-08 | Alb. Klein Kg, 5241 Niederfischbach | Verfahren zur Reinigung von Schüttgütern durch Zentrifugalkräfte sowie Vorrichtung zur Durchführung des Verfahrens |
GB1463749A (en) * | 1974-08-21 | 1977-02-09 | British Leyland Uk Ltd | Apparatus for use in producing a fluidised bed of granular material |
US3970547A (en) * | 1975-05-22 | 1976-07-20 | Raytheon Company | Air classification apparatus |
GB1493774A (en) * | 1975-05-22 | 1977-11-30 | Raytheon Co | Materials separating apparatus |
DE2921197A1 (de) * | 1979-05-25 | 1980-12-04 | Hermann J Linder | Verfahren und vorrichtung zum regenerieren von giessereisand |
GB2061770A (en) * | 1979-10-27 | 1981-05-20 | Futtans Ltd | Improvements in or relating to the separation of granular mixtures |
-
1982
- 1982-08-30 AU AU87845/82A patent/AU542894B2/en not_active Ceased
- 1982-08-31 BR BR8205096A patent/BR8205096A/pt unknown
- 1982-09-01 DE DE8282304595T patent/DE3268559D1/de not_active Expired
- 1982-09-01 EP EP82304595A patent/EP0074755B1/fr not_active Expired
- 1982-09-01 CA CA000410616A patent/CA1209784A/fr not_active Expired
- 1982-09-02 ZA ZA826431A patent/ZA826431B/xx unknown
- 1982-09-02 ES ES515460A patent/ES8308242A1/es not_active Expired
- 1982-09-02 JP JP57153345A patent/JPS5853346A/ja active Pending
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2478461A (en) * | 1946-03-16 | 1949-08-09 | Nichols Eng & Res Corp | Apparatus and method for treating foundry sand |
Also Published As
Publication number | Publication date |
---|---|
AU542894B2 (en) | 1985-03-21 |
ES515460A0 (es) | 1983-08-16 |
AU8784582A (en) | 1983-03-10 |
DE3268559D1 (en) | 1986-02-27 |
CA1209784A (fr) | 1986-08-19 |
JPS5853346A (ja) | 1983-03-29 |
EP0074755A1 (fr) | 1983-03-23 |
ZA826431B (en) | 1984-04-25 |
BR8205096A (pt) | 1983-08-09 |
ES8308242A1 (es) | 1983-08-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2813318A (en) | Method and apparatus for treating granular material | |
US5509971A (en) | Process for removing coatings from hard surfaces | |
US2478461A (en) | Apparatus and method for treating foundry sand | |
US5322532A (en) | Large size sodium bicarbonate blast media | |
GB2145643A (en) | Method and apparatus for cleaning by abrasive blasting | |
JPH0338014B2 (fr) | ||
WO1994016833A1 (fr) | Milieu de grenaillage moins agressif prepare avec des particules comprimees | |
US3716947A (en) | Abrasive blast cleaning system | |
US2622047A (en) | Ligno-cellulose aggregate and blast cleaning process employing the same | |
US3694964A (en) | Abrasive blast cleaning system | |
EP0074755B1 (fr) | Procédé pour la récupération de sables de fonderie | |
US6817927B2 (en) | Method of removing material from an external surface using core/shell particles | |
US4449566A (en) | Foundry sand reclamation | |
US2766496A (en) | Method and apparatus for cleaning foundry sand | |
JPS63207563A (ja) | 放電加工による金型の研掃方法 | |
US3829029A (en) | Abrasive blast cleaning system | |
EP2296847B1 (fr) | Minéral contenant du carbonate alcalino-terreux pour nettoyage de surface | |
JP3015713B2 (ja) | 金属廃棄物の除染処理方法およびその装置 | |
US3257759A (en) | Process for surface altering | |
US3738415A (en) | Method of molding articles and reclaiming the foundry sand used | |
US3690066A (en) | Abrasive blast cleaning system | |
WO2022011985A1 (fr) | Procédé et dispositif de recyclage de sable résiduel de fonderie | |
US5259434A (en) | Method of regenerating used foundry sands | |
JPH04258367A (ja) | 粉粒体の清浄方法及び装置 | |
JPS58937B2 (ja) | 無機質粘結剤を用いた鋳物砂の再生利用方法 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Designated state(s): BE DE FR GB IT NL SE |
|
RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: UNILEVER NV Owner name: UNILEVER PLC |
|
17P | Request for examination filed |
Effective date: 19830907 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Designated state(s): BE DE FR GB IT NL SE |
|
ITF | It: translation for a ep patent filed |
Owner name: JACOBACCI & PERANI S.P.A. |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Effective date: 19860131 |
|
REF | Corresponds to: |
Ref document number: 3268559 Country of ref document: DE Date of ref document: 19860227 |
|
ET | Fr: translation filed | ||
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: BE Effective date: 19860930 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
BERE | Be: lapsed |
Owner name: UNILEVER N.V. Effective date: 19860930 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Effective date: 19870401 |
|
NLV4 | Nl: lapsed or anulled due to non-payment of the annual fee | ||
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19870527 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee | ||
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Effective date: 19870901 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Effective date: 19881121 |