US20110108232A1

US20110108232A1 - Binder material

Info

Publication number: US20110108232A1
Application number: US12/899,511
Authority: US
Inventors: Frederick Scott Cannon; John T. Fox; He Huang; Robert C. Voigt; James C. Furness; Paul D. Paulsen; Gregory Sanders; Matthew Robert Lumadue; Allura Marie Jiles; Paul Jonathan Munson; Sridhar Komarneni; Nicole Robitaille Brown; James A. Devenne, JR.
Original assignee: Penn State Research Foundation
Current assignee: Penn State Research Foundation
Priority date: 2009-10-06
Filing date: 2010-10-06
Publication date: 2011-05-12

Abstract

A binder material for binding a plurality of particles together to form a conglomerate such as a carbon-containing briquette, a sand casting core and the like is provided. The binder material can include a collagen and/or lignin and a plurality of inorganic particles. In some instances, the binder material can be used to make a composite material. The composite material can include a plurality of particles and the binder material that contains the collagen and/or lignin. The binder material affords for the plurality of particles to be bound together into a desired shape, the desired shape having desirable properties.

Description

FIELD OF THE INVENTION

The present invention relates to a binder system for binding particles together, and in particular, to binding system containing a collagen or lignin and an inorganic material.

BACKGROUND OF THE INVENTION

The price increase of energy sources and raw materials in recent years is known. For example, iron foundries with cupola furnaces use foundry coke as a conventional fuel and the price of the foundry coke increased by about 450% from the year 2002 to 2008. FIG. 1 illustrates a simplified scheme of a typical cupola furnace used to continuously melt/make cast iron. At the start of a production run, the cupola is filled with layers of coke and ignited. After the coke is ignited, a strong air flow is introduced to the coke bed through tuyeres and solid pieces of metal, e.g. scrap iron, are charged into the furnace through a charging door once a desired temperature is achieved. The solid pieces of metal are alternated with additional layers of fresh coke, and limestone is added as a flux. Silicon is also added and reacts with carbon to form silicon carbide which can improve cast iron quality.
In typical iron cupola furnaces, for every 1000 pounds of scrap iron charged into the furnace, approximately 100 pounds of coke, 1 pound of silicon, 20 pounds of limestone, along with other additives, are added or charged into the furnace[1]. The overall dwell time for charged materials is typically 40-80 minutes which avails about 20-40 minutes in a preheat zone where the material experiences temperatures in the range of 1200-1400° C. in a reducing/starved-air (pyrolysis) environment.
Before coke is provided to the cupola furnace, it is produced by pyrolysis of special coking bituminous coals [2-4]. Once produced, the coke has desirable chemical and physical properties suitable for burning in the cupola furnace. For example, the coke has a fused porous carbon structure that affords for a fast burning fuel bed to be developed above the molten iron within the cupola furnace[4].
One draw back from using foundry coke is the fact that only a small fraction of mineable coal resources offer desirable coking properties. In addition, the manufacture of coke consumes large amounts of energy. As such, research on a coking replacement has been conducted, but as of yet achieved limited success, and coke is still the most used fuel in cupola furnaces.
It is of interest to note that before the development of coke, anthracite was widely used as a fuel source in cupola furnaces. Anthracite offers similar chemical properties as coke, however, the combustion rate of chunks or pellets of anthracite is relatively slow due to the materials condensed structure. The combustion rate of anthracite chunks can be increased by reducing chunk size[1], however if anthracite pieces become too small, they can be blown out of the furnace via the strong tuyere air flow before adequate or complete combustion can occur. Indeed, there are minimum size specifications for solid fuels used in iron cupola furnaces.
As such, anthracite fines represent a heretofor unusable residue from anthracite mining processes and are often left as waste in collection ponds, valleys, etc., of coal mining regions. Although organic binders have been used to bind anthracite fines into bricks, heretofor developed or employed organic binders have not been able to survive the high temperature conditions in the cupola furnace. Therefore, there is a need for a binder to bind particles such as anthracite fines, to make pellets, bricks, and the like such that the pellets, bricks, etc., can withstand high temperatures and mechanical forces experienced in cupola furnaces.
In addition to the need for a foundry coke alternative, the metal casting industry extensively uses sand molds and sand cores made from silica sand and organic binders, with conventional binders used for the manufacture of sand cores emitting up to 70% of a foundry's Volatile Organic Compound (VOC) emissions[5].
A sand core can containing between 1 to 3% of a binder with the remaining portion being sand. The binder must provide a core with adequate strength at room temperature and structural integrity when exposed to molten metal. Paradoxically, after withstanding molten metal thermal exposure and subsequent cooling, the binder must then breakdown during shake-out so that the sand can be easily removed from cavities of a cast product.
Several petroleum based binder systems in use today, such as phenolic urethanes and furans, provide the desired structural integrity, shakeout propensity and casting quality. However, the phenolic urethane and furan binders breakdown after metal solidification and can emit between 30 to 70% of a foundry's VOC's and Hazardous Air Pollutants (HAP's) [5,6]. Furthermore, VOC and HAP emissions increase proportionately with an increase in core-loading[5,7,8].
Researchers have shown that VOC emissions for a collagen core binder are 70-95% less than for a phenolic urethane binder[6,9]. Collagen, which is available in large quantities as a by-product of the meat-packing industry, is a fibrous triple helical protein that strengthens skin, tendon and bones, and has a tensile strength greater than steel. However, despite significant emission reductions enabled by collagen, the material has been marginally employed in foundries due to its inability to withstand high temperatures imparted by molten iron (1290° C.-1510° C.) at the molten metal/sand interface. Specifically, breakdown of collagen at high temperatures results in erosion of the core and costly casting defects. As such, there is also a need for a binder for sand cores that can withstand the harsh environment of metal casting and yet has lower VOC emission in comparison to phenolic urethanes and furans.

SUMMARY OF THE INVENTION

The present invention discloses a binder material for binding a plurality of particles together to form a conglomerate such as a carbon-containing briquette, a sand casting core and the like. The binder material can include a first component that can contain a collagen and/or lignin and a second component that can contain a metal, a metalloid and/or an inorganic compound. In some instances, the binder material can be used to make a composite material. The composite material can include the plurality of particles and the binder material. The binder material affords for the plurality of particles to be bound together into a desired shape, the desired shape having desirable properties for a particular use of the composite material.
The plurality of particles can be a plurality of sand particles, i.e. grains of sand, or in the alternative, a plurality of carbon-containing particles such as coal particles, coke particles, anthracite fines, anthracite fines that have been ground into a powder, and the like. The plurality of sand particles can be bound together to form a casting component, for example a sand casting core, a sand casting mold, etc. The plurality of carbon-containing particles can be bound together to form a fuel pellet which may or may not have a plurality of silicon carbide nanowires as part of the fuel pellet structure/morphology. In some instances, silicon carbide nanowires nucleate and grow when the fuel pellet is heated above 1200° C. in a reducing and/or pyrolysis gaseous atmosphere.
The first component can contain denatured collagen and the second component can contain inorganic particles such as particles of an amorphous silica-rich ash, silicate, ferrosilicon, silicon, combinations thereof and the like. In the event that the particles include a silicate, the silicate can be an alkaline metal silicate, alkaline earth metal silicate, combinations thereof, etc. In some instances, the second component provides a source of silicon which can react with the carbon-containing particles to form silicon carbide, which may or may not be in the form of nanowires. In addition, the nanowires can assist in binding of the plurality of component particles together to form the component. The binder material can also include an organic component, e.g. a biomatieral and/or a carbohydrate. The carbohydrate can be a saccharide which may or may not include a monosaccharide such as glucose, fructose, galactose, xylose, ribose, etc.
A process for making a conglomerate using the binder system can include mixing the plurality of particles with the binder material and forming or molding the mixture into a desired shape. In some instances, the binder material is pre-heated before mixing with the plurality of particles. Thereafter, the desired shape can be dried and may or may not be exposed to ultraviolet radiation that can assist in curing of the shape.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a cupola furnace;

FIG. 2 is graph of unconfined compressive strengths for briquettes pyrolyzed at 900° C. for 30 minutes and made from 100 g anthracite, 2 g collagen, 0 or 10 g silicon metal powder and 0 to 10 g lignin (plus water); Lignin A=hardwood lignin precipitated from Kraft black liquor via sulfuric acid addition; Lignin B=hardwood lignin extracted via Lignoboost™ process; and Lignin C=Sigma Aldrich low sulfonate lignin;

FIG. 3 is a plurality of x-ray diffraction (XRD) plots for various anthracite pellet materials before and after being subject to a pyrolysis treatment at 1400° C.;

FIG. 4 is a plurality of scanning electron microscopy (SEM) images for: (a,b) collagen+kaolinite bindered anthracite fines; (c,d) collagen+sodium silicate bindered anthracite fines; and (e,f) collagen+silicon powder bindered anthracite fines;

FIG. 5 is a transmission electron microscopy (TEM) image of a silicon carbide nanowire;

FIG. 6 is a graphical representation of unconfined compressive strength for anthracite pellets as a function of pellet composition;

FIG. 7 is a plurality of SEM images for collagen+silicon powder bindered anthracite pellets made with: (a,c) original anthracite fines; and (b,c) anthracite powder;

FIG. 8 is a schematic illustration of the cupola furnace in FIG. 1 illustrating full scale testing of anthracite pellets made according to an embodiment of the present invention;

FIG. 9 is graphical representation of percent mass retained as a function of temperature for different binders subjected to thermal gravimetric analysis (TGA) testing;

FIG. 10 is a graphical representation of TGA-mass spectroscopy (TGA-MS) data for the detection of NO₂as a function of temperature for three different binder materials: collagen; phenolic urethane; and collagen+Li/K silicate;

FIG. 11 is a graphical representation of TGA-MS data for the detection of benzene as a function of temperature for three different binder materials: collagen; phenolic urethane; and collagen+Li/K silicate;

FIG. 12 is a graphical representation of TGA-MS data for the detection of phenol as a function of temperature for three different binder materials: collagen; phenolic urethane; and collagen+Li/K silicate;

FIG. 13 is a graphical representation of TGA-MS data for the detection of xylene as a function of temperature for three different binder materials: collagen; phenolic urethane; and collagen+Li/K silicate;

FIG. 14 is a graphical representation of storage modulus as a function of temperature for various binder materials;

FIG. 15 is a graphical representation of tan delta as a function of temperature for various binder materials; and

FIG. 16 is a graphical representation of deflection as a function of temperature for different bindered silica sand cores subjected to hot distortion testing.

DETAILED DESCRIPTION OF THE INVENTION

The present invention discloses a binder system, also referred to as a binder material or simply as a binder, for binding together particles such as anthracite fines, silica sand grains, and the like. As such, the present invention has utility for making a conglomerate such as a carbon-base briquette or a sand casting core. For the purposes of the present invention, the term conglomerate is defined as shape, part, tool and the like made from at least two different materials, wherein the materials adhere to one another. The carbon-containing pellet can be used as a fuel source in a cupola foundry furnace, a steel making blast furnace and the like, or in the alternative, the sand casting core can be used in a molten metal casting process. For the purposes of the present invention, conglomerate and composite material are used interchangeably. In addition, conglomerates include cores, sand casting cores, carbon-containing briquettes, briquettes, pellets, and bricks. The terms cores and sand casting cores are used interchangeably, as are the terms carbon-containing briquettes, briquettes, pellets, and bricks.
The binder material can include a first component that can contain collagen and/or lignin and a second component that can contain a metal, a metalloid and/or an inorganic compound. The collagen may or may not be denatured and can be mixed with an aqueous solution that can further be mixed with the second component and/or a plurality of component particles. Other additives can be included in the binder material, for example and for illustrative purposes only, organic compounds that include biomass, biomass derived material, carbohydrates such as saccharides, monosaccharides and the like. For the purposes of the present invention, the term biomass is defined as living or dead vegetation or vegetation derived matter, animal, and/or animal derived material, excluding petroleum and petroleum products.
The binder material can be mixed with a plurality of particles to make a composite material that can be formed and/or molded together into a conglomerate having a desired shape, the conglomerate having desirable properties. For example and for illustrative purposes only, the conglomerate can be a fuel briquette or brick, also referred to as a fuel pellet herein, that can be used in a cupola furnace. The fuel pellet can be made from a mixture of the binder material and waste anthracite fines, and the pellet can replace at least part of the foundry coke used by the cupola furnace. The fuel pellet can also exhibit mechanical properties that afford for the pellet to be stored, shipped and/or fed into an industrial cupola furnace without excessive breakage and/or burning.
The plurality of particles used to make the conglomerate can have different shapes, sizes, chemical compositions, mechanical properties and the like. In some instances, 50% by weight or mass of the plurality of particles bindered by the binding material in order to make a conglomerate have an average mean diameter of less than 0.25 inches. In other instances, the plurality of particles are sand particles that have an American Foundry Society (AFS) grain fineness number between 25 and 150, inclusive.
The conglomerate can also be a sand casting core made from the binder material and a plurality of sand grains/particles. The sand core can exhibit adequate and/or desired high temperature strength, liquid metal erosion resistance and shake-out qualities. In addition, the sand core can exhibit or provide a significant reduction in volatile organic compounds (VOC) emissions and hazardous air pollutants (HAP) when compared to traditional binders such as a phenolic urethane, furan, etc.
The second component can contain a silicate, ferrosilicon, silicon, combinations thereof and the like. In the event that the second component contains a silicate, the silicate can be an alkaline metal silicate, alkaline earth metal silicate, an amorphous silica-rich ash and combinations thereof. For example and illustrative purposes only, the silicate can be sodium silicate, potassium silicate, lithium silicate, magnesium silicate, calcium silicate, kaolinite, and combinations thereof. In addition, the amorphous silica-rich ash as can be an ash derived from rice hulls and rice stalks. In some instances, the second component provides a source of silicon which can react with carbon-containing particles and form silicon carbide, which may or may not be in the form of nanowires. In addition, the nanowires can assist in binding of the plurality of particles together to form the conglomerate and provide desirable mechanical properties thereto.
A process for making a conglomerate using the binder system can include mixing the plurality of particles with the binder material and forming or molding the mixture into a conglomerate having a desired shape. In some instances, the binder material is pre-heated before mixing with the plurality of particles. Thereafter, the conglomerate can be dried and may or may not be exposed to ultraviolet radiation that may assist in curing of the conglomerate.
In order to better teach and/or disclose the present invention, and yet in no way limit the scope thereof, examples of at least two embodiments are provided below.

Manufacture and Testing of Fuel Pellets

Number 5 (#5) anthracite fines (hereafter referred to simply as “anthracite fines”) were obtained from Jeddo Coal Company located in Wilkes-Barre, Pa. A sieve analysis of the anthracite fines illustrated a particle size between US mesh # 10-80 (2000 to 177 μm). In some instances, the anthracite fines were crushed into powders that could pass through a U.S. mesh #100 (150 μm) sieve (hereafter referred to as “anthracite powder”).
Chemical analysis and heat content of the anthracite fines were compared with a typical foundry coke used by Ward Manufacturing in Blossburg, Pa., with results shown in Table 1 below. As shown in the table, the dry heat content of the anthracite fines was approximately the same as for foundry coke.

TABLE 1

	Proximate analysis %	Heat

Volatile

Fixed

Ultimate analysis % (ash free)

content

Name	matter	Carbon	Ash	C	H	N	S	O	(mJ/kg)

Anthracite	4.99	82.3	12.8	94.3	2.25	0.89	0.38	2.59	29.88
Coke	1.30	90.81	7.89	96.1	0.75	1.61	0.68	0.95	30.74

A dry granular collagen-based binder was provided by Entelechy, representing Hormel Foods Company in Austin, Minn. Fructose (98%-102%) was obtained from Mallinckrodt Baker, Inc., in Phillipsburg, N.J.
Three different lignins were acquired and tested. The first lignin was low sulfonate alkali lignin purchased from Sigma-Aldrich, the second was a hardwood lignin extracted from Kraft black liquor via sulfuric acid precipitation, and the third was a hardwood lignin extracted via the Lignoboost™ process which extracts lignin from black liquor in part by lowering the pH of the liquor with CO₂.
Three forms of silicon having three different redox levels were obtained and tested. Metallic silicon (Si) having zero valence and in the form of 10 cm or less lumps was purchased from Alfa Aesar in Ward Hill, Mass. The lumps were crushed into powders of less than #100 mesh before being mixed with the anthracite fines and/or anthracite powder. Amorphous Si having +4 valence and in the form of a sodium silicate (Na₂SiO₃) solution containing 42.5% by weight of dry solids was provided by J.B. DeVenne Inc., in Berea, Ohio. And crystallized Si having +4 valence in the form of kaolinite powder (KGa-1, Al₂Si₂O₅(OH)₄) was obtained from Washington County, Ga.
The anthracite fines were dried at 105° C. overnight to remove moisture and 1 g of collagen binder was dissolved in 12 g of water at 70° C. to form a gelatin solution. In some instances, fructose was added and dissolved in the water plus collagen binder solution. A Si source, either the metallic Si or the kaolinite powder, was mixed with the anthracite fines, or in the alternative, the Si-containing liquid solution (sodium silicate) was added to the gelatin solution. Thereafter, the anthracite fines, with or without the Si source depending on which form of Si was being used, were mixed with the gelatin solution without or with the Si-containing liquid solution, respectively. The final mixture of anthracite fines and gelatin solution was then packed into a cylindrical mold (2.86 cm diameter×4.76 cm long) with 275 kPa (40 psi) pressure applied on both ends. Finally, a conglomerate in the form of a pellet was extruded from the mold and cured under ambient conditions with at least three anthracite pellets produced from a single batch or final mixture. During curing, evaporation released approximately 10 g of the initial 12 g of water.
Mechanical strength of the pellets at room temperature was determined using unconfined compressive strength testing and drop shatter testing[10]. The unconfined compressive strength of anthracite pellets was determined using a Simpson-Gerosa electronic universal sand strength machine. A horizontally moving arm applied pressure on a pellet until failure. Final compressive force was calculated based on the diameter of the original pellet sample, assuming negligible shape change during the test. The sample preparation and unconfined compressive strength procedure disclosed herein are defined as an unconfined compressive strength test protocol.
The drop shatter test was a standard breakage test used for foundry coke with results often referred to as an anti-breakage strength. The anthracite pellets were dropped onto a steel plate through a 1.83 meter (m) long polyvinylchloride (PVC) tube that had an inner diameter of 3.8 cm. A total of 10 drops for each pellet was performed with a first end of the pellet pointing in the down direction for a given drop, followed by a second end of the pellet pointing in the down direction for the next drop. After the tenth and final drop, the weight of the largest remaining piece of the pellet was obtained. In addition, if no single piece having a mass larger than 50% of the original weight of the pellet remained after a drop, the test was stopped and 0% was recorded for the test. The sample preparation and drop testing procedure disclosed herein are defined as a drop test protocol.
Pyrolysis of the anthracite pellets was conducted in a horizontal tube furnace or a vertical tube furnace. When using the horizontal tube furnace, a pellet was placed in an alumina tube extending through the furnace and a slow nitrogen gas flow of approximately 2 standard cubic centimeters per minute was used to prevent the anthracite from burning. In addition, a three-step pyrolysis procedure was employed with the furnace ramped at 3° C./min up to 1400° C., holding at 1400° C. for 2 hours, and then furnace cooling to room temperature at 3° C./min. The pyrolyzed anthracite pellets were then removed from the tube-furnace for further tests. Unless otherwise identified, the prescribed maximum temperature was 1400° C., which is generally close to preheating zone temperatures of a cupola furnace. This pyrolysis procedure is defined as a horizontal furnace pyrolysis protocol.
For pyrolysis in the vertical tube furnace, the furnace was heated to a predefined temperature with a laminar flow of nitrogen gas provided up through a vertical alumina tube extending through the furnace. Thereafter, a 5 g sample was placed in a basket and descended into the heated tube. A thermocouple was used to record the temperature of the region where the sample was located and it was determined that the sample region increased from 30-40° C. to 800° C. within about 2-3 minutes, where the temperature remained for the prescribed time. This pyrolysis procedure is defined as a vertical furnace pyrolysis protocol.
Burning rates for the anthracite fines and foundry coke were determined by measuring the time required for complete combustion of approximate 5 g pieces of anthracite pellets and foundry coke. Specifically, a piece of an anthracite pellet or foundry coke was placed in a 5 cm diameter quartz tube furnace and heated to 1050° C. under an inert and/or reducing atmosphere. Thereafter, the piece was held at 1050° C. within the tube for between 2-3 minutes and then air at about 2 L/s was passed up through the tube and into contact with the material. The air thus provided oxygen for burning of the piece and a time was recorded for when combustion was no longer observed.
Scanning electron microscopy (SEM) analysis was performed using a FEI Quanta 200 Environmental SEM with a Gaseous SE detector, a voltage of 20 kV and an electron beam spot size of 4 nm. A transmission electron microscope (TEM, Model 2010, JEOL, Tokyo, Japan) was also used to determine material morphology, particle size and electron diffraction.
Ambient temperature XRD patterns were obtained using a PANalytical X'Pert Pro MPD diffractometer and powders of the anthracite pellets were obtained by crushing a pellet with a ball mill. It is appreciated that the XRD patterns provided a bulk measurement of the material.
Anthracite pellets were prepared with an array of compositions and protocols. For example, anthracite pellet compositions included 100 g of anthracite fines, 1 g of collagen, 0 to 1 g of fructose, 0 to 10 g lignin and 0 to 10 g of silicon, kaolinite or sodium silicate. Results of unconfined compressive strength tests as described above for anthracite pellets having different compositions, excluding lignin, are shown in Table 2 below. As shown by the data in the table, the use of collagen and/or fructose as a binder material provides strength to the pellets before pyrolysis and as such can provide strength at lower temperatures that would be experienced by anthracite pellets during shipping, storage and/or initially entering a cupola furnace. The data also show that pellets made with 10 g silicon metal powder achieved the most favorable unconfined compressive strengths: 1300 kPa before pyrolysis and 690 kPa after pyrolysis. In addition, 1% fructose increased the strength of 10 g silicon powder pellets even more. In contrast, the 10 g sodium silicate addition offered considerable unconfined compressive strength (2344 kPa) before pyrolysis, but only 28 kPa after pyrolysis. Pellets made with kaolinite exhibited negligible strength after pyrolysis. It is of interest to note that for all three Si sources, less Si corresponded to lower strengths.

TABLE 2

		Unconfined	Drop shatter	Unconfined
		compressive	remaining	compressive
Carbon		strength before	before	strength after
Source	Other additives	pyrolysis (kPa)	pyrolysis (%)	pyrolysis (kPa)

100 g	No other additives	1234	76	0
anthracite	1 g fructose	1095	99	0
fines + 1 g	3 g sodium silicate	N/D	90	0
collagen	(0.7 g as silicon)
	6 g sodium silicate	2455	99	0
	(1.4 g as silicon)
	10 g sodium silicate	2342	98	~28
	(2.3 g as silicon)
	1 g kaolinite	N/D	91	0
	(0.22 g as silicon)
	10 g kaolinite	1340	93	~7
	(2.2 g as silicon)
	2 g silicon	1230	77	69
	5 g silicon	N/D	80	345
	10 g silicon	1250	91	690
	1 g fructose,	1300	99	720
	10 g silicon
Foundry	No additives	2758	93	2758
Coke

Regarding the addition of lignin to the binder material, FIG. 2 is a graph of unconfined compressive strengths determined by the unconfined compressive strength protocol for briquettes pyrolyzed at 900° C. for 30 minutes and made from 100 g anthracite, 2 g collagen, 0 or 10 g silicon metal powder and 0 to 10 g lignin (plus water). Regarding the legend in FIG. 2, Lignin A was the hardwood lignin extracted from Kraft black liquor via sulfuric acid precipitation, Lignin B was the hardwood lignin extracted via the Lignoboost™ process and Lignin C was the low sulfonate alkali lignin purchased from Sigma-Aldrich. The figure illustrates that higher lignin amounts yield higher unconfined compressive strengths, even without the presence of silicon, in an intermediate temperature range that would be experienced for anthracite pellets fed into a cupola furnace. It is appreciated that foundry coke has an unconfined compressive strength of about 300 psi, thus further illustrating improved binding with the use or addition of lignin.
Looking now at FIG. 3, XRD patterns illustrate a crystal structure change within the anthracite pellets induced by pyrolysis at 1400° C. The raw anthracite fines, i.e. before pyrolysis, contained muscovite [KAl₂(AlSi₃O₁₀)(F,OH)₂], kaolinite, and quartz (SiO₂) (FIG. 3 a). The presence of crystallized Si (+4 valence) was also detected. After pyrolysis, muscovite and kaolinite were converted into mullite (Al₆Si₂O₁₃), and the carbon became more crystallized as evidenced by a sharper hump or peak between 2 theta of 20° and 30°. Pyrolysis of the anthracite fines alone yielded no silicon carbide.
When 10 g of kaolinite powder was bindered to 100 g anthracite fines with 1 g of collagen, the kaolinite XRD peaks that appeared before pyrolysis were converted mostly to mullite. This kaolinite-anthracite combination also did not yield silicon carbide.
In contrast, when collagen bindered anthracite fines included sodium silicate as the Si source, pyrolysis of the material yielded beta silicon carbide (3C—SiC) (FIG. 3 f). In addition, the pyrolysis resulted in a net-reduction of Si (+4) valence and a net increase of Si (0) valence. It is appreciated that the amorphous structure of the sodium silicate may have enhanced the kinetics of this redox reaction.
The formation of SiC increased when 10 g of silicon metal powder was bindered to 100 g anthracite fines with 1 g of collagen and pyrolyzed (FIGS. 3 g & 3 h). In particular, after pyrolysis the silicon metal XRD peaks were significantly reduced while very strong diffraction peaks for the cubic crystal structure of 3C—SiC were observed. As such, zero valence silicon and carbon reacted with each other to form silicon carbide during pyrolysis of the material.
Turning now to FIG. 4, SEM images of anthracite pellet morphology after pyrolyis at 1400° C. and as a function of the different Si-containing additives are shown. For the kaolinite-anthracite system (FIG. 4 a), the kaolinite powders were sintered into larger ceramic features that spanned across neighboring anthracite particles. A higher magnification of the anthracite pellet surface (FIG. 4 b) illustrates numerous spheres were generated from the transformation of kaolinite to mullite plus silica. In addition, the spherical shapes indicated that the transformed kaolinite to mullite plus silica was liquid and exhibited a low adhesive force with the anthracite surface.
When sodium silicate was the additive, the pyrolyzed products exhibited sponge-like ceramic structures (FIGS. 4 c & 4 d) that were similar to the sodium silicate precursor structure. The ceramic structure was not composed of silicon carbide, as indicated by the EDS spectrum inset in FIG. 4 d, although some SiC was present within the pyrolyzed anthracite-sodium silicate. The presence of silicon carbide nanowires (SCNWs) was not observed.
In contrast, the 10 g silicon powder additive resulted in a labyrinth of SCNWs. The nanowires were generally 20 μm in length with lengths up to 100 μm observed. Per visual inspection, the nanowires altered the color of the pellets from the black of anthracite to the light green of the nanowires. In addition, the SCNWs were observed to have formed after heating of the anthracite pellet above 1200° C. for times as low as 6 minutes and as such can provide improved strength at higher temperatures that would experienced by anthracite pellets fed into a cupola furnace. As such, the SCNWs were formed and/or present when the anthracite pellets were pyrolized above 500° C., e.g. above 900° C., 1000° C., 1100° C. and/or 1200° C.
The nanowires were typically 20-50 nm in diameter and were coated by an amorphous thin layer (about 2 nm thick) of silicon oxide as shown in the high resolution TEM (HRTEM) image in FIG. 5. The SCNWs were also highly crystallized and per the XRD pattern in FIG. 3 h, the silicon carbide was 3C—SiC which has a face centered cubic structure. The space between two planes in FIG. 5 was about 0.25 nm which is concurrent with the calculated value for a 3C—SiC crystal structure (0.251 nm). The stacking faults in FIG. 5 confirmed that the nanowires were grown by stacking of the (111) lattice plane in the [111] direction.
The effect of anthracite particle size on anthracite pellet binding strength was also examined. With a smaller particle size, e.g. using anthracite powder to make a pellet, gaps between anthracite particles were reduced and SiC nanowires were able span between adjacent anthracite particles. FIG. 6 provides a graph showing post-pyrolysis strength of anthracite pellets as a function of pellet composition for pellets made with silicon powder and/or anthracite powder. As shown in the graph, for a given silicon content, anthracite pellets made from 100% anthracite powder (<#100 mesh) could be as much as 5 times stronger than anthracite pellets made from 100% anthracite fines (#10 to 80 mesh). In addition, post-pyrolysis strength of anthracite pellets was enhanced by using a mixture of anthracite powder and anthracite fines. For example, pellets made from 50% anthracite powder and 50% anthracite fines were only slightly weaker than pellets made from 100% anthracite powder. The positive effect of using silicon powder is also shown in FIG. 6.
SEM images in FIG. 7 illustrate the differences between anthracite particle size. In particular, for anthracite pellets made from 100% anthracite fines, relatively large void spaces between the anthracite particles were observed (FIG. 7 a) and the SCNWs were not long enough to span from one anthracite grain to another. As such, SCNWs could bind the anthracite particles only in regions at or near touching points between adjacent particles (FIGS. 7 a & 7 c). In contrast, pellets made from 100% anthracite powder exhibited relatively small void spaces (FIG. 7 b) and the SCNWs spanned between adjacent particles (FIG. 7 d). In addition, even when anthracite pellets were made from 50% fines and 50% powder, the smaller particles could fit within voids between the larger particles and thereby reduce void space and afford for SCNWs to span and/or bind adjacent particles.
Turning now to Table 3, a comparison of burning rates for different compostion anthracite pellets and foundry coke at 1050° C. is shown. It is appreciated from the data that pieces of anthracite pellets had burn rates generally equivalent to pieces of coke. In contrast, unbound anthracite fines burned considerably faster.

TABLE 3

Sample	Time for fully burn (min)

Coke pieces	18.75, 19.5
Anthracite pellet pieces (100 g powdered	18.5, 17.5
anthracite, 4 g silicon, 1 collagen)
Anthracite pellet pieces	22.3
(25 g powdered anthracite, 75 g anthracite
fines, 10 g silicon, 1 g collagen)
Unbound anthracite fines (#10 × 80)	5.25, 4.5

Full scale testing of anthracite fine bricks made from anthracite fines, collagen binder, fructose additive, and silicon powders was performed by feeding the bricks into an industrial foundry cupola. In total, 500 pounds of anthracite bricks generally measuring 5.75 inches (14.6 cm) in diameter, 2.25 inches (5.7 cm) in height and weighing 1.8 pounds (0.82 kg) were prepared.
The testing included feeding the bricks into the cupola for about one hour at a rate that replaced 10% of the coke that would have otherwise been used (FIG. 8). The anthracite bricks were dropped about 10 feet into a hopper bucket along with scrap metal, coke, silicon bricks, limestone, etc., and the hopper afforded for the materials to be fed into the cupola. In addition, the feeding rate of the silicon bricks was diminished by about 5-8% in order to account for the silicon in the anthracite bricks.
When the anthracite bricks were dropped into the bucket, no breakage was observed as per visual inspection. Breakage was also not observed, as per remote video camera, when the bricks were conveyed into the top of the cupola. As the anthracite bricks descended through the cupola melt zone and past the tuyere windows, 10 to 12 shapes that exhibited a tell-tale smooth curvature of a 14 cm circle were observed and it appeared that a number of these shapes were anthracite bricks. None of the bricks had broken into pieces by the time they passed the tuyere windows and the bricks appeared to be burning throughout their structure while in the melt zone, as were chunks of coke.
The product or resulting metal quality and chemical composition produced by the cupola furnace, along with cupola temperatures and pressures, were analyzed during the full-scale demonstration. The metal product quality and chemistry parameters were within experimental error, although back pressure and temperature (represented by the upper-stack temperature) of the cupola increased slightly during the addition of the anthracite bricks. It is appreciated that the increase in back pressure and temperature could have resulted from the anthracite-silicon bricks burning faster than the coke. However, it is also appreciated that cupola operation is complicated and affected by many factors, and as such, no conclusions could be drawn relating the changes in temperature and back pressure to the addition of the anthracite bricks.

Manufacture and Testing of Sand Casting Cores

Samples of binder material and sand casting cores made with the binder material were prepared for thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC) and hot distortion testing (HDT). In general, TGA and DSC samples contained no sand and were prepared with only the binder components listed in Table 4. DMA and HDT samples were prepared with sand and binder. DMA samples were molded into gum-stick sized core samples generally measuring 12 mm×5 mm×35 mm and HDT samples were molded into candy bar sized samples generally measuring 15.24 cm×2.54 cm×1.27 cm.

TABLE 4

	Composition for	Composition for
Name	TGA and DSC Samples	DMA and HDT Samples

Sodium	10 g Modified Sodium	3 g Solution, 100 g Sand
Silicate	Silicate
Collagen	10 g Collagen, 30 mL Water	1 g Collagen, 100 g Sand
C + K/Li	10 g Collagen, 8.7 g K/Li	1 g Collagen, 0.87 g K/Li
Silicate	Silicate (solids content)	Silicate (solids), 100 g Sand
C + Na	10 g Collagen, 8.5 g Na-	1 g Collage, 0.85 g Na-
Silicate	Silicate (solids content)	Silicate (solids), 100 g Sand
Phenolic	0.55 parts A, 0.45 parts B	1 g Phenolic Urethane,
Urethane		100 g Sand

A modified sodium silicate solution containing 42.5% by weight of dry solids was provided by J.B. DeVenne and Associates in Berea, Ohio. Collagen in the form of dry powder was provided by Entelechy in Canton, Mich. A phenolic urethane binder that was heat was provided by Ashland Chemical Company in Columbus, Ohio. The phenolic urethane binder came as a two-part binder (Part A and Part B) that cured when mixed and heated. Potassium silicate was provided by PQ Corporation in Malvern, Pa. and came as a liquid with 29% by weight solids content. Silica sand having a specified American Foundry Society (AFS) AFS grain fineness number ranging from 67-73 was provided by Wedron Silica Company in Wedron, Ill.
In one embodiment of a binder material/system, 10 g of collagen was added into 20 mL of modified sodium silicate with 5 grams of triglycerides, and the entire mixture was heated to 70° C. and vigorously stirred for 5 minutes. The hybrid mixture was then poured into an aluminum pan and dried at 110° C. for 12 hours. Phenolic urethane samples were prepared with 55 parts A to 45 parts B, as is common in industry practice, and then dried at 110° C. for 24 hours. Another hybrid binder material was prepared by mixing 10 g collagen with 2.9 grams of K/Li silicate solids, the mixture also dried at 110° C. for 12 hours.
For TGA tests, a small portion of dried binder (10 to 20 mg) was removed with a scalpel and placed in a TA instruments SDT 2960—Simultaneous DSC-TGA instrument. The test commenced at room temperature under an argon atmosphere and was heated at 10° C./min to 600° C. Trials were tested in duplicate with an average between the duplicates taken/used as final TGA results. The sample preparation and TGA procedure disclosed herein are defined as a TGA test protocol.
For DSC tests, binder samples were shaved and finely powderized with a razor blade. DSC analyses used a 2.0 mg sample and employed a TA Instruments TA-Q100 DSC instrument. A hermetic pan was used to hold samples with the pan lid punctured with an 8 penny finish nail to prevent the pan from ‘jumping’ from the heating element during analysis. Samples were purged with nitrogen gas at 50 mL/min. Two tests were performed using a temperature ramp of 10° C./min to 510° C. A third test was performed using a temperature ramp of 10° C./min to 510° C., followed by cooling at 20° C./min to 50° C. and then ramping at 10° C./min to 510° C. a second time. The sample preparation and DSC procedure disclosed herein are defined as a DSC test protocol.
For DMA and HDT experiments, bindered cores were made by mixing 1 to 3% binder material with 99 to 97% silica sand (Table 4). Bindered core samples were prepared by mixing 1.0 kg of washed foundry silica sand with a given binder material for 90 seconds at Level ‘2’ Solid State Speed Control, in a Commercial Kitchen Aid Mixer, Model Number KSMC50S.
For DMA analyses, the mixed material was hand packed into an 8-part wooden core mold that produced samples sizes described above. Samples were then cured at 110° C. for one hour, with the exception of heat cured phenolic urethane bindered samples which cured for 24 hours. The samples were then removed from the core mold and placed in a dessicator for overnight storage.
TEA-cured phenolic urethane samples were provided by the Penn State University HMAC foundry and were produced using 1.1% phenolic urethane cured with TEA gas in a full-scale/industrial operation. The cores of the samples had a 3 inch×1 inch diameter rod protruding from a main core, which was removed and manually filed down to a size that could be used for DMA testing.
For DMA analyses, samples were analyzed using a TA Instruments DMA q800 unit with a dual cantilever clamp. The samples were heated at 10° C./min to 500° C., while a middle support oscillated at a frequency of 20 Hz and a 5 μm amplitude. During testing, the samples were maintained under a nitrogen gas atmosphere flowing at 2 L/min. The sample preparation and DMA procedure disclosed herein are defined as a DMA test protocol.
For HDT analyses, samples were formed into hand packed cores in a 16 sample wooden core box. The bindered cores were cured in the core box at 110° C. for 1 hour, with the exception of phenolic urethane bindered cores which were cured for 24 hours.
The HDT was performed using a custom HDT device that clamped 2.54 cm of a first end portion of the sample onto an iron ledge. The samples were then heated in the center of the exposed 12.7 cm of the sample using a natural gas flame from a 2.54 cm perforated Bunsen burner having an adiabatic flame temperature of 1960° C. and a micrometer detected deformation of the sample at a location 1.27 cm from a second end of the sample. In addition, the micrometer transmitted deformation readings every second to a computer which logged the data. For each binder composition, 10 to 15 samples were analyzed. It is appreciated that the results exhibited inherent variability in both time to given deflection and deflection at failure. The sample preparation and HDT procedure disclosed herein are defined as an HDT protocol.
Molten metal erosion testing was also performed on sand core samples. The sand cores were produced with collagen, sodium silicate, sodium silicate plus collagen, lithium silicate plus collagen (two variations), heat cured phenolic urethane and TEA cured phenolic urethane. The cores were hand packed and had a general final size of 5 in. long×5 in. wide×2 in. thick—with the exception of TEA cured phenolic urethane cores which were 3 in. wide×2.75 in. thick. The cores were placed on a stand leaning at a 45° angle and molten iron at 2620-2720° F. was poured onto the surface of the core from a height of about 8 inches using a constant head core. After pouring the molten metal over a core sample, the metal was captured in a ladle and weighed. The sand cores were then removed and evaluated for erosion and surface characterization.
Core evaluation was performed using core scratch hardness and a micrometer to measure erosion depth. In addition, sand was used to fill any eroded away region in order to quantify erosion volume. The cores were evaluated for core hardness before and after the pour with hardness measured one inch from where molten metal flowed off the core. The erosion depth was measured using Mitutoyo calipers and sand was poured into an erosion cavity, if present, and scraped off using a metal bar. The quantity of sand required to fill the cavity was then measured in order to quantify sand volume eroded during metal pouring. The sample preparation and molten metal erosion testing procedure disclosed herein is defined as an molten metal erosion testing protocol.
Turning now to FIG. 9, core binder TGA data show the mass retained by the tested binder material at high temperatures. The inorganic sodium silicate retained the most mass up to the highest temperatures (80% at 500° C.) whereas collagen retained the least mass (50% at 328° C.) and phenolic urethane (heat cured) retained 50% mass at 438° C. It is appreciated that the collagen+sodium silicate (50% mass loss at 646° C.) and collagen+K/Li silicate (50% mass loss at 600° C.) binders best reproduced or were closest to the mass loss exhibited by the heat cured phenolic urethane.
In addition to mass retained, FIGS. 10-13 provide TGA-mass spectrometry (TGA-MS) semi-quantitative NO₂, benzene, phenol, and xylene emission data, respectively, for three sand core samples: one bindered with 1% Collagen; one bindered with 1% phenolic urethane (TEA cured); and one bindered with 1% Collagen+0.87% Li/K silicate.
The TGA-MS testing utilized a TA Instruments TGA 2050 coupled to a mass spectrometer (ThermoStar™ 301T, Pfeiffer Vacuum) which measured the gaseous effluent. In addition, an Ashland Isocure Focus(R) WTC Binder having 0.55 g of part 1 and 0.45 g part II per gram of binder was used as the phenolic urethane binder. Conglomerate samples weighing 400 mg were used for the TGA-MS testing and the samples contained approximately 1% organic binder, dry mass basis. The samples were cured by conventional processing technology and were not exposed to temperatures higher than curing conditions. Once cured, a sample was placed in an alumina pan which was subsequently placed in the TGA-MS furnace and heated from room temperature to 1000° C. at a rate of 10° C./min. The furnace, and thus the sample, were purged with 100% ultra-high purity argon gas for a minimum of one hour prior to analysis and for the duration of analysis using a gas flow rate of 90 mL/min.
The MS provided a response measured in nanoamps (nA) as a function of temperature for each atomic mass unit (AMU) analyzed. From the measured nA as a function of temperature data, a plot as shown in FIG. 10-13 can be constructed. Thereafter, a straight line is drawn between nA data corresponding to 50° C. and 900° C. This straight line is taken, and hereafter referred to, as the baseline. A maximum response is generally visible from the plot and measured and/or determined as the maximum nA value less the baseline nA value at the temperature corresponding to the maximum nA value.
The AMU responses for benzene were taken for an AMU of 78, for phenol an AMU of 94 and for xylene an AMU of 106. As shown in FIGS. 11-13, TGA-MS analysis of a collagen+K/Li silicate sample provided a maximum response of 0.000007 nA for benzene, 0.000003 nA for xylene and 0.000004 nA for phenol. In comparison TGA-MS analysis of a TEA cured phenolic urethane sample provided a maximum response of 0.000113 nA for benzene, 0.000031 nA for xylene and 0.000010 nA for phenol. As such, within a temperature range between 50° C. and 900° C. the collagen+K/Li silicate sample and/or an inventive binder material disclosed herein mixed with silica sand to produce a conglomerate can release less than about a 0.00008 nA response attributed to benzene when compared to a 50-900° C. benzene baseline value, and/or less than about a 0.000015 nA response attributed to xylene when compared to a 50-900° C. xylene baseline value, and/or less than about a 0.000008 nA response attributed to phenol when compared to a 50-900° C. phenol baseline value.
As such, an inventive binder disclosed herein can provide a reduction in benzene of at least 60%, a reduction in xylene of at least 60% and/or a reduction in phenol of at least 50% compared to the phenolic urethane tested herein. In the alternative, an inventive binder can provide a reduction in benzene of at least 70%, a reduction in xylene of at least 70% and/or a reduction in phenol of at least 60% compared to the phenolic urethane tested herein. In still another alternative, an inventive binder can provide a reduction in benzene of at least 80%, a reduction in xylene of at least 80% and/or a reduction in phenol of at least 65% compared to the phenolic urethane tested herein. In still yet another alternative, an inventive binder can provide a reduction in benzene of at least 90%, a reduction in xylene of at least 90% and/or a reduction in phenol of at least 67.5% compared to the phenolic urethane tested herein.
When conducting these analyses, the TGA-MS responses were normalized by analyzing a standard sample of 27.9 mg calcium oxalate. For this standard calcium oxalate sample, the maximum response for AMU 44, attributed to CO₂, was about 5 nA total when compared to a baseline of 0 nA at about 800° C. When the nA response for calcium oxalate is different than this, the test samples could be normalized accordingly. In addition, the sample preparation and TGA-MS procedure disclosed herein are defined as a TGA-MS protocol.
Each sample was heated in 100% argon at 10° C./min to 1000° C. with air emissions monitored via mass spectrometry. As shown in the figures, collagen emits significantly less VOCs than phenolic urethane. For example, FIG. 11 illustrates that phenolic urethane emits over 35% more benzene than collagen at temperatures around 580 to 600° C. A significant reduction in phenol and xylene emissions by collagen when compared to phenolic urethane is also shown in FIGS. 12 and 13.
Regarding DMA testing, FIG. 14 illustrates that all the binder systems have similar storage moduli at room temperature (approximately 1500-2250 MPa). However, significant changes occur with increased temperatures with phenolic urethane and sodium silicate losing their stiffness at temperatures around 150 to 200° C. In addition, collagen rapidly lost its stiffness at 250° C. which corresponds to the temperature that Collagen experiences significant mass loss (see FIG. 9).
Not being bound by theory, it is postulated that bindered core DMA performance in the 300 to 500° C. range correlates to a bindered core's resistance to cracking-type failure which can lead to erosion. As such, a higher storage modulus in this temperature range corresponds to less failure. In that perspective, collagen alone was the lowest performing material since it offered the lowest storage modulus of 10-100 MPa in this range. Sodium silicate was the highest performer at 400-900 MPa and phenolic urethane (heat cured) was 50-100 MPa. The collagen+silicate binders performed well with values between 50-300 MPa in the stated temperature range. It is appreciated that the low storage modulus for collagen in the temperature range of 275° C. to 400° C. may contribute to core erosion when the collagen is exposed to molten metal.
Referring now to FIG. 15, a graph of DMA tan delta as a function of temperature is shown. Tan delta is a unitless parameter that corresponds with the tangent of the phase lag of material response. This phase lag is defined as the ratio of modulus loss (E□□—the component of the modulus that has a time-dependent or viscous response) to storage modulus (E□; which represents the elastic or instantaneous response). As such, peaks in the tan delta versus temperature data represent a sudden change in the time-dependent nature of response. For polymers, this is typically interpreted as a glass transition.
As shown in FIG. 15, the first peak temperature for collagen was 262° C., whereas the first peak for phenolic urethane was 201° C. The collagen's glass transition temperature was 262° C. and it exhibited a very narrow tan delta peak which would correspond to brittle behavior above this temperature. Brittleness was in fact observed for all the samples after the DMA testing. The phenolic urethane exhibited a glass transition at 201° C. and both the collagen+silicate hybrids exhibited glass transitions at approximately 260-270° C. (FIG. 15 and Table 3). It is appreciated that the collagen+silicate binder peaks were relatively broad, and as such, the hybrid binders could offer a more favorable thermal response when compared with phenolic urethane.

TABLE 5

		T(° C.) for
Storage Modulus	Tan Delta	Storage

System

	300° C.	450° C.	Peak	T(° C.)	Modulus <1400 MPa

Collagen	21.62	98.63	0.75	263	250
Phenolic	188.9	70.21	0.38	201	100
Urethane
(Heat Cured)
Phenolic	52.8	45.5	0.31	230	X
Urethane
(TEA Cured)
Sodium	362.4	682.6	0.63	273	180
Silicate
Collagen +	71.7	163.9	0.36	262	n/a
Sodium
Silicate
Collagen +	54.3	163.9	0.47	258	n/a
Li/K
Silicate

HDT core samples distorted while being heated by the natural gas flame with results shown by the graph in FIG. 16. The phenolic urethane, sodium silicate and both collagen+silicate bindered cores distorted to a maximum degree measurable with the instrument which was 13.5 mm. In addition, the collagen bindered core was the only core that did not reach the maximum distortion, but rather broke at approximately 4 mm of distortion. It is appreciated that the collagen+sodium silicate and collagen+lithium/potassium silicate bindered cores required the longest time to reach maximum distortion as shown in FIG. 16 and Table 6 below. It is also appreciated that rapid distortion at high temperatures provides unwanted core behavior, for example yielding casting defects. Thus the ability of the collagen+sodium silicate and collagen+lithium/potassium silicate bindered cores to withstand thermal stress for the longest amount of time can be favorable.


	Average Time	Average	Average Final
	to 1 mm	Distortion at	Distortion
Binder System	Distortion (sec)	Breaking (mm)	Time (sec)

1% Collagen	65.4	4.2	71.3
1% Heat Cured	50.1	13.5	84.5
Phenolic Urethane
1.28% Sodium	21.7	No break	30.3
Silicate
Collagen + Sodium	29.0	No break	197.4
Silicate
Collagen + Li/K	83.4	No break	152.1
Silicate

Looking now at Table 7, when molten iron was poured onto the cores, the sodium silicate and both collagen+silicate cores did not exhibit measurable erosion as shown by the zero readings in the table. In contrast, the phenolic urethane (P-U) cores exhibited slight erosion and the collagen cores exhibited significant erosion. The phenolic urethane cores lost only 0.02 cm of core depth and 0.42 to 0.72 grams of sand per kilogram of iron poured. The collagen core exhibited the greatest erosion, while experiencing the least molten iron. For example, the collagen core erosion depth and sand erosion were approximately 20 times greater and over 10 times greater, respectively, per kilogram of molten iron when compared with the phenolic urethane core samples.
The sodium silicate core decreased slightly in hardness whereas the collagen and collagen+silicate cores exhibited more significant decreases in hardness when experiencing a similar amount of molten iron. Also, the hardness of the phenolic urethane core decreased significantly when experiencing molten iron, to less than half the sodium silicate core hardness.

TABLE 7

	Sample

					0.85%	0.87%
		P-U¹	P-U	1.28%	Na Sil,	Li/K Sil,
Parameter	Collagen	(HC)²	(TEA)³	Na Sil ⁴	1% Col ⁵	1% Col

Iron	Kg	8.50	16.98	18.81	17.03	17.61	19.01
Poured
Hardness	Pre-	77.5	73.5	85.5	76.0	78.5	85.0
	Pour
	Post-	33.3	24.7	29.8	64.0	44.2	45.5
	Pour
Erosion	Total	3.08	0.36	0.33	0	0	0
Depth	(cm)
	cm/kg	0.362	0.021	0.018	0	0	0
	Iron
Sand	Total (g)	44.19	12.30	7.92	0	0	0
Erosion	g/kg	5.20	0.72	0.42	0	0	0
	Iron

¹Phenolic urethane
²Heat cured phenolic urethane
³TEA cured phenolic urethane
⁴silicate
⁵collagen

In view of the teaching presented herein, it is to be understood that numerous modifications and variations of the present invention will be readily apparent to those of skill in the art. As such, the foregoing is illustrative of specific embodiments of the invention but is not meant to be a limitation upon the practice thereof. It is the following claims, including all equivalents, which define the scope of the invention.

REFERENCES

[1] American Foundrymen's Society. Cupola handbook; American Foundrymen's Society, 1975.
[2] Kirk, E. The cupola furnace; Henry Carey Baird & Co, Philadelphia, 1903.
[3] World-Bank in Pollution prevention and abatement handbook ( ) pp. 286-290 (World Bank Publications, Washington D.C., 1998).
[4] Avallone, E., Baumeister, T. & Sadegh, A. Standard handbook for mechanical engineers; McGraw-Hill Professional, 2006.
[5] Glowacki, C. R., G. R. Crandell, et al. (2004). “Emissions Studies at a Test Foundry using an Advanced Oxidation Clear Water System.” American Foundry Society Transactions. 3.
[6] Wang, Y., F. S. Cannon, et al. (2007). “Characterization of hydrocarbon emissions from green sand foundry core binders by analytical pyrolysis.” Environmental Science & Technology 41(22): 7922-7927.
[7] Goudzwaard, J. E., C. M. Kurtti, et al. (2004). “Foundry Emissions Effects with an Advanced Oxidation Blackwater System.” American Foundry Society Transactions. 79(3): 20.
[8] Schifo et al., 2003
[9] CERP (2000). CERP-Technicon, LLC. Comparison of Binder Systems relative to Emissions (Orally presented data; on CERP web page).
[10] Richards, S. R. (1990). Fuel Process. Technol. 25, 89-100.

Claims

1. A binder material for binding a plurality of particles together in order to make a conglomerate, said binder material comprising:

a first component containing an organic material selected from a group consisting of a collagen and a lignin; and

a second component containing an inorganic material selected from a group consisting of an element and an inorganic compound.

2. The binder material of claim 1, wherein said second component is a plurality of inorganic materials.

3. The binder material of claim 1, wherein said inorganic material is selected from a group consisting of a silicate, a ferrosilicon and silicon.

4. The binder material of claim 3, wherein said silicate is selected from a group consisting of an alkaline metal silicate, alkaline earth metal silicate, an amorphous silica-rich ash and combinations thereof.

5. The binder material of claim 4, wherein said amorphous silica-rich ash is an amorphous silica-rich ash of rice hulls and rice stalks.

6. The binder material of claim 3, wherein said silicon is a zero valence silicon.

7. The binder material of claim 1, further comprising a saccharide.

8. The binder material of claim 7, wherein said saccharide is a monosaccharide selected from a group consisting glucose, fructose, galactose, xylose and ribose.

9. A composite material comprising said plurality of particles and said binder material of claim 1.

10. The composite material of claim 9, wherein said binder material has a heat flow between −0.5 and −2.5 Watts per gram for temperatures between 50 to 450° C. as measured by a differential scanning calorimetry protocol.

11. A conglomerate comprising said plurality of particles and said binder material of claim 9, said plurality of particles bound together into a desired shape by said binder material.

12. The conglomerate of claim 11, wherein said plurality of particles are selected from a group consisting of a plurality of coal particles, a plurality of anthracite particles, a plurality of sand particles, a plurality of lignocellulosic particles, a plurality of lignin particles, a plurality of carbonaceous particles, a plurality of silicon dioxide particles, and a plurality of aluminosilicate particles.

13. The conglomerate of claim 11, wherein 50% by mass of said plurality of component particles have an average mean diameter of less than 0.25 inches.

14. The conglomerate of claim 11, wherein said plurality of particles are sand particles having an AFS grain fineness number between 25 and 150, inclusive.

15. The conglomerate of claim 12, wherein said desired shape is a fuel pellet.

16. The conglomerate of claim 15, wherein said fuel pellet is a pyrolyzed fuel pellet having a plurality of silicon carbide nanowires.

17. The conglomerate of claim 12, wherein said desired shape is a sand casting core.

18. The conglomerate of claim 12, wherein said desired shape has an unconfined compressive strength of greater than 1000 kPa before a pyrolysis treatment when measured by an unconfined strength test protocol.

19. The conglomerate of claim 12, wherein said desired shape has an unconfined compressive strength of greater than 1000 kPa after a pyrolysis treatment at 900° C. when pyrolyzed per a vertical furnace pyrolysis protocol and measured by an unconfined compressive strength protocol.

20. The conglomerate of claim 12, wherein said desired shape has an unconfined compressive strength of greater than 500 kPa after a pyrolysis treatment at 1400° C. when pyrolyzed per a horizontal furnace pyrolysis protocol and measured by an unconfined compressive strength protocol.

21. The conglomerate of claim 12, wherein said desired shape has 75% remaining weight after drop testing per a drop testing protocol.

22. The conglomerate of claim 12, wherein said desired shape has a storage modulus greater than 150 MPa at 450° C. when measured in accordance with a dynamic mechanical analysis protocol.

23. The conglomerate of claim 12, wherein said desired shape distorts at least 14 mm before failure when measured by a hot distortion test protocol.

24. The conglomerate of claim 12, wherein said desired shape distorts less than 4 mm in 20 seconds when measured by a hot distortion test protocol.

25. The conglomerate of claim 12, wherein said desired shape erodes less than 0.02 cm per kg molten iron poured when measured by a molten iron erosion test protocol.

26. A conglomerate comprising:

silica sand and a binder material;

said binder material having an organic component, said organic component being less than about 1% by dry mass of said conglomerate;

wherein said conglomerate distorts less than 10 mm in 100 seconds and distorts at least 14 mm before failure when measured by a hot distortion test protocol.

27. A conglomerate comprising:

a plurality of coal particles and a binder material;

said binder material having a biomass component, said biomass component being between 1 and 10% by dry mass of said conglomerate;

wherein said conglomerate has an unconfined compressive strength greater than 3000 kPa after pyrolysis at 900° C. when measure by an unconfined compressive strength protocol and pyrolyzed by a vertical furnace pryrolysis protocol.

28. A conglomerate comprising:

silica sand and a binder material, said binder material having an organic component, said organic component being about 1% by dry mass of said conglomerate;

wherein said conglomerate distorts less than 10 mm in 50 seconds and distorts at least 14 mm before failure when measured by a hot distortion test protocol; and

wherein within a temperature range between 50° C. and 900° C. said conglomerate releases less than about 0.00008 nA response attributed to benzene when compared to a 50-900° C. benzene baseline value, or said conglomerate releases less than about 0.000015 nA response attributed to xylene when compared to a 50-900° C. xylene baseline value, or said conglomerate releases less than about 0.000008 nA response attributed to phenol when compared to a 50-900° C. phenol baseline value when measured by a TGA-MS protocol.

29. A conglomerate comprising:

wherein said conglomerate has a reduction in benzene of at least 60%, a reduction in xylene of at least 60% and/or a reduction in phenol of at least 50% compared to benzene, xylene and/or phenol emissions from a silica sand and phenolic urethane binder material when measured using a TGA-MS protocol.

30. A process for making a conglomerate from a composite material, the process comprising:

providing a plurality of particles;

providing a binder material having a first component and a second component, the first component containing an organic substance selected from a group consisting of a collagen and a lignin, and the second component containing an inorganic substance selected from a group consisting of an element and an inorganic compound.

mixing the plurality of particles with the binder material to make a conglomerate mixture;

forming the conglomerate mixture into a desired shape; and

drying the desired shape.

31. The process of claim 30, wherein the binder material includes an aqueous liquid.

32. The process of claim 31, further including pre-heating the binder material before mixing with the plurality of particles.

33. The process of claim 30, wherein the binder includes a saccharide.

34. The process of claim 30, further including exposing the desired shape to ultraviolet radiation.

35. The process of claim 30, wherein the plurality of particles are silica sand particles and the desired shape is a sand casting core.

36. The process of claim 30, wherein the plurality of particles are anthracite fines particles and the desired shape is fuel pellet.

37. The process of claim 30, wherein the desired shape has a plurality of silicon nanowires when pyrolyzed above 1200° C. per a horizontal furnace pyrolysis protocol.

38. The process of claim 30, wherein the desired shape has an unconfined compressive strength of greater than 1000 kPa before pyrolysis when measured by an unconfined compressive strength test protocol.

39. The process of claim 30, wherein the desired shape has an unconfined compressive strength of greater than 1000 kPa after pyrolysis at 900° C. using a vertical tube furnace protocol and when measured by an unconfined compressive strength test protocol.

40. The process of claim 30, wherein the desired shape has an unconfined compressive strength of greater than about 500 kPa after pyrolysis at 1400° C. using a horizontal tube furnace protocol and when measured by an unconfined compressive strength test protocol.

41. The process of claim 30, wherein the desired shape before pyrolyis has 75% remaining weight after drop testing per a drop testing protocol.

42. The process of claim 30, wherein the desired shape has a storage modulus greater than 150 MPa at 450° C. when measured by a dynamic mechanical analysis protocol.

43. The process of claim 30, wherein the binder material has a heat flow between −0.5 and −2.5 Watts per gram for temperatures between 50 to 450° C. as measured by a differential scanning calorimetry protocol.

44. The process of claim 30, wherein the desired shape distorts at least 14 mm before failure when measured by a hot distortion test protocol.

45. The process of claim 30, wherein the desired shape distorts less than 4 mm in 20 seconds when measured by a hot distortion test protocol.

46. The process of claim 30, wherein the desired shape erodes less than 0.02 cm per kg molten iron poured when measured by a molten iron erosion test protocol.