The results of investigations of the granulation process of foundry dusts generated in the dry mechanical reclamation process of used sands, where furan resins were binders are presented in the paper. Investigations concerned producing of granules of the determined dimensions and strength parameters. Granules were formed from the dusts mixture consisting in 50 mass% of dusts obtained after the reclamation of the furane sands and in 50 mass % of dusts from sands with bentonite. Dusts from the bentonite sands with water were used as a binder allowing the granulation of after reclamation dusts from the furane sands. The following parameters of the ready final product were determined: moisture content (W), shatter test of granules (Wz) performed directly after the granulation process and after 1, 3, 5, 10 days and nights of seasoning, water-resistance of granules after 24 hours of being immersed in water, surface porosity ep and volumetric porosity ev. In addition the shatter test and water-resistance of granulate dried at a temperature of 105oC were determined. Investigations were performed at the bowl angle of inclination 45o, for three rotational speeds of the bowl being: 10, 15, 20 rpm. For the speed of 10 rpm the granulation tests of dusts mixture after the preliminary mixing in the roller mixer and with the addition of water-glass in the amount of 2% in relation to the amount of dust were carried out. The obtained results indicate that the granulator allows to obtain granules from dusts originated from the reclamations of moulding sands with the furane resin with an addition of dusts from the bentonite sands processing plants.

The aim of the hereby paper is to present the developed model of determining the volume and surface porosity based on the main fraction

of polifractional materials, its experimental verification and utilisation for the interpretation of effects accompanying the formation of a

moulding sand apparent density, porosity and permeability in the blowing processes of the core and moulds technology.

Mechanical reclamation process of spent moulding sands generate large amounts dusts containing mainly rubbed spent binding agents and quartz dust. The amounts of post-reclamation dusts, depending of the reclamation system efficiency and reclaim dedusting system, can reach 5 -10% in relation to the total reclaimed moulding sand. This dust due to the high content of the organic substances is a threat to the environment and therefore requires the storage on landfills specially adapted for this type of waste. On the other hand, the presence of organic substances causes that these dusts have relatively high energy values that could be used. However, at present there is no coherent, environmentally friendly concept for the management of this type of dust. The paper presents the results of tests of thermal utilization the dusts (as a source of energy) were carried out at AGH University of Science and Technology. Thermal utilization of dusts was carried out in the co-burning with carbon carriers process or in individual burning (Patent PL 227878 B1 and patent application PL - 411 902).

Experiments of filling the model moulds cavity of various inner shapes inserted in rectangular cavity of the casting die (dimensions: 280

mm (height) x 190 mm (width) x 10 mm (depth) by applying model liquids of various density and viscosity are presented in the paper.

Influence of die venting as well as inlet system area and inlet velocity on the volumetric rate of filling of the model liquid – achieved by

means of filming the process in the system of a cold-chamber casting die was tested. Experiments compared with the results of simulation

performed by means of the calculation module Novacast (Novaflow&Solid) for the selected various casting conditions – are also

presented in the paper.

The paper, especially dealt with problems of reclamation of used furan sand, carried out in new, vibratory sand reclamation unit REGMAS

developed by researches from AGH-University of Science and Technology, Faculty of Foundry Engineering in Cracow (Poland).

Functional characteristics of reclamation unit as well as the results of reclamation of used sand with furfuryl resin are discussed in the

paper. The quality of reclaim was tested by means of the LOI and pH value, dust content in the reclaim and at least by the the quality of

the castings produced in moulds prepared with the use of reclaimed matrix.

The effects of filling the core box cavity and sand compaction in processes of core production by blowing methods (blowing, shooting)

depend on several main factors. The most important are: geometrical parameters of cavity and complexity of its shape, number,

distribution and shape of blowing holes feeding sands as well as the venting of a technological cavity. Values of individual parameters are

selected according to various criteria, but mostly they should be adjusted to properties of the applied core sand.

Various methods developed by several researchers, including the authors own attempts, allow to assess core sands properties on the basis

of special technological tests projecting the process into a laboratory scale. The developed criteria defining a degree or a filling ability

factor provide a better possibility of assessing the core sand behavior during flowing and core box filling, which indicate the value and

structure of the obtained compacting decisive – after hardening – for strength and permeability. The mentioned above aspects are analyzed

– on the basis of authors’ own examinations - in the hereby paper.

The cumulative results of investigations of the possibility of using the reclaimed materials after the mechanical, thermal or

mechanical-thermal reclamation for making cores by means of the blowing method in the alkaline CO2 technology, are

presented in the paper. Three kinds of spent sands: with furfuryl resin, bentonite and alkaline phenolic resin, obtained from

the foundry, were subjected to three kinds of reclamation: mechanical, thermal and combined mechanical-thermal, applying

for this aim adequate experimental devices. The obtained reclaims were assessed with regard to the degree of the matrix

liberation from the determined binding material. Reclaims of moulding sands with binders of the form of resin were assessed

with regard to ignition loss values and pH reaction, while reclaims of moulding sands with bentonite with regard to the

residual clay content and pH value. In all cases the results of the performed sieve analyses were estimated and the average

characteristic diameter dl was determined. The reclaimed matrix was applied as a full substitute of the fresh high-silica sand in typical

procedures of preparing core sands used for making shaped samples for bending strength investigations, Rg

u

.

The investigation results of the mechanical reclamation of spent moulding sands from the Cordis technology are presented in the paper.

The quality assessment of the obtained reclaim and the influence of the reclaim fraction in a matrix on the core sand strength is given. The

reclaim quality assessment was performed on the basis of the determination of losses on ignition, Na2O content on reclaim grains and pH

values. The reclaim constituted 100%, 75% and 50% of the core sand matrix, for which the bending strength was determined. The matrix

reclamation treatment was performed in the experimental rotor reclaimer RD-6. Spent sands were applied in as-delivered condition and

after the heating to a temperature of 140 o

C. Shaped samples for strength tests were made by shooting and hardening of sands in the warmbox

technology.

The problem related to the management of post reclamation dusts generated in the reclamation process of waste moulding sands with

organic binders is presented in the hereby paper. Waste materials generated in this process are products hazardous for the environment and

should be utilised. The prototype stand for the utilisation of this dangerous material in its co-burning with coal was developed and patented

in AGH in Krakow. The stand was installed in one of the domestic casting houses. As the utilisation result the transformed waste product

is obtained and its management in the production of ceramic materials constitutes the subject of the presented publication.