Abstract: A process for producing fuel from biomass is disclosed herein. The process includes torrefying biomass material at a temperature between 80° C. and 300° C. to form particulated biomass having a mean average particle size from about 1 ?m to about 1000 ?m. The particulated biomass is mixed with a liquid to form a suspension, wherein the liquid comprises bio-oil, wherein the suspension includes between 1 weight percent to 40 weight percent particulated biomass. The suspension is fed into a hydropyrolysis reactor; and at least a portion of the particulated biomass of the suspension is converted into fuel.

Abstract: A method and apparatus for effective pyrolysis of a biomass utilizing rapid heat transfer from a solid heat carrier or catalyst. Particularly, various embodiments of the present invention provide methods and apparatuses which incorporate progressive temperature quenching and rapid disengagement of the heat carrier material and reaction product.

Abstract: A process and method transforms solid waste into fuel. The system uses a pressure vessel; a condenser tank to permit selective addition of water to and evacuation of steam from the vessel; a heater to increase the temperature of the vessel; a vacuum pump to selectively reduce pressure within the vessel and to help evacuate steam from the vessel to the condenser tank; and a water pump to selectively add water from the condenser tank to the interior volume of the vessel.

Abstract: A process for the conversion of coal into fuel bases comprises two successive direct liquefaction stages in ebullated bed reactors followed by a fixed bed hydrocracking stage. This process can produce excellent quality fuel bases (kerosene and diesel).

Abstract: The invention relates to a process for the manufacture of diesel range hydrocarbons wherein a feed is hydrotreated in a hydrotreating step and isomerised in an isomerisation step, and a feed comprising fresh feed containing more than 5 wt % of free fatty acids and at least one diluting agent is hydrotreated at a reaction temperature of 200-400° C., in a hydrotreating reactor in the presence of catalyst, and the ratio of the diluting agent/fresh feed is 5-30:1.

Abstract: The present invention addresses the processing of waste and low-value products to produce useful materials in reliable purities and compositions, at acceptable cost, without producing malodorous emissions, and with high energy efficiency. In particular, the invention comprises a multi-stage process that converts various feedstocks such as offal, animal manures, municipal sewage sludge, tires, and plastics, that otherwise have little commercial value, to useful materials including gas, oil, specialty chemicals, and carbon solids. The process subjects the feedstock to heat and pressure, separates out various components, then further applies heat and pressure to one or more of those components. Various materials produced at different points in the process may be recycled and used to play other roles within the process. The invention further comprises an apparatus for performing a multi-stage process of converting waste products into useful materials, and at least one oil product that arises from the process.

Abstract: An appliance is provided having a waste receptor module and an energy generation module for converting household waste into energy. The receptor module has a rotary drum with an opening for receiving the household waste and a steam reforming means for converting the waste into synthesis gas. A swing arm is attached adjacent to the opening in the rotary drum and a sealing door is mounted on the swing arm for sealing the opening when the waste receptor module is in operation. An outer door is used to cover the sealing door. The steam reforming means includes a tube mounted within the rotary drum for receiving the volatilized organic waste and an internal heater for heating the organic waste to temperatures to convert the waste into the synthesis gas. The energy generation module has an inlet in fluid communication with the waste receptor module for receiving the synthesis gas and a fuel cell for converting the synthesis gas into electrical energy.

Abstract: Waste processing system, for performing a waste processing process, the system including a shredder, a grinder and a steam explosion device such as a cooking extruder. The waste processing system is used to process raw waste, such as consumer waste, into an end product such as pellets. The waste processing includes an acid treatment step to sanitize, purify and/or increase a cellulose content of the waste. The acid is preferably a weak acid and/or an organic acid.

Abstract: A process and system for converting organic waste into reusable hydrocarbon is described wherein the process includes feeding an organic waste into a pyrocatalytic reactor which is essentially free of halogenated synthetic resinous material into a molten lead bath which is confined in a reactor in an substantially oxygen-free atmosphere which is admixed with a catalytic material comprising particulate aluminum oxide and aluminum powder. The waste is thermally and catalytically converted with at least 50% effectiveness to produce a reusable hydrocarbon.

Abstract: To provide a method for catalytically cracking waste plastics wherein the efficiency in decomposition is high; even polyethylene composed of linear chain molecules difficult in decomposition is decomposable at a low temperature and decomposed residue is hardly produced; the process is simple since dechlorination can be achieved at the same time with catalytically cracking waste plastics in one reaction vessel; and oil fractions can be recovered at 50% or more on a net yield basis. The method for catalytically cracking waste plastics of the present invention has a constitution in which waste plastics are loaded as a raw material into a granular FCC catalyst heated to a temperature range from 350° C. to 500° C. inside a reaction vessel, thereby decomposing and gasifying the waste plastics in contact with the FCC catalyst.

Abstract: The invention relates to recycled rubber produced by a process comprising the steps of: a) shredding cleaned rubber tires into shreds less than 2? long; b) pyrolyzing the shreds in a reaction chamber of a thermal processor in a first anaerobic environment to produce a char; c) drawing off volatile organics from the reaction chamber; c) removing the char from the reaction chamber; d) cooling the char in a second anaerobic environment; e) removing metal and textile components from the char to obtain pyrolytic carbon black; f) milling and sizing the pyrolytic carbon black so obtained into particles of 325 mesh size or smaller; and, g) utilizing the pyrolytic carbon black from the previous step in a polymerization process that produces said recycled rubber. It also relates to the high quality pyrolytic carbon black recovered from this process.

Abstract: Recycling a metal/organic laminate continuously involves providing a reactor having a first chamber with a first rotary stirrer, a second chamber with a second rotary stirrer, each chamber containing particulate microwave absorbing material, introducing laminate and additional absorbing material into the first chamber under a reducing or inert atmosphere, stirring and applying microwave energy sufficiently to pyrolyze organic material, transferring a portion of the mixture to the second chamber where it is stirred and microwave energy applied to pyrolyze remaining organic material, delaminate or delaminated metal migrating toward and floating on the upper surface of the mixture, where the second stirrer rotates in a horizontal plane and fluidizes the mixture to give the upper surface of the mixture a radial profile biasing metal floating to migrate radially outwardly, and recovering metal from an exit.

Abstract: A method produces a hydrocarbonaceous fluid (a liquid mixture of hydrocarbons, or in other words a mixture of hydrocarbons which is liquid at ambient room temperature and atmospheric pressure), which functionally is a liquid hydrocarbon fuel, from a feed of waste plastic. The method comprises in broad embodiments the steps of: (step 1) melting a feed of substantially solid waste plastic in an aerobic atmosphere (for instance, air) whereby a waste-plastic melt is produced; (step 2) distilling at least a portion of the waste-plastic melt whereby a hydrocarbonaceous distillate is produced; and (step 3) collecting the hydrocarbonaceous distillate. That distillate is generally referred to above as a condensate. In some preferred embodiments, the method includes the step of commutating the feed of substantially solid waste plastic into pieces substantially no greater than about 1.5 cm2 prior to step 1.

Abstract: In a method and apparatus for thermal processing of catalytically active biomass, the biomass is subjected in a receiving tank to a cracking temperature to undergo a cracking reaction. The biomass is transferred to a mixer pump to produce a reaction mixture which is directed into an outgassing chamber of an intermediate tank to produce an outgassed fraction and a non-outgassed liquid fraction. The outgassed fraction to produce fuel is cooled down, and a first portion of the non-outgassed liquid fraction is returned and subjected again to the cracking temperature in the receiving tank. A second portion of the non-outgassed liquid fraction is conducted in a bypass to the outgassing chamber of the intermediate tank for outgassing while fresh biomass is added. Residual matter settling in the intermediate tank is periodically removed.

Abstract: A process for improving cold flow properties of diesel range hydrocarbons produced from renewable feedstocks such as plant oils and animal oils. A renewable feedstock is treated by hydrogenating and deoxygenating to provide an effluent comprising paraffins followed by isomerizing and selectively hydrocracking at least a portion of the paraffins to generate a diesel range hydrocarbon product. A portion of the diesel range hydrocarbon product is selectively separated and recycled to the isomerization and selective hydrocracking zone.

Abstract: To provide a method for catalytically cracking waste plastics wherein the efficiency in decomposition is high; even polyethylene composed of linear chain molecules difficult in decomposition is decomposable at a low temperature and decomposed residue is hardly produced; the process is simple since dechlorination can be achieved at the same time with catalytically cracking waste plastics in one reaction vessel; and oil fractions can be recovered at 50% or more on a net yield basis. The method for catalytically cracking waste plastics of the present invention has a constitution in which waste plastics are loaded as a raw material into a granular FCC catalyst heated to a temperature range from 350° C. to 500° C. inside a reaction vessel, thereby decomposing and gasifying the waste plastics in contact with the FCC catalyst.

Abstract: A method of recycling composite material comprising carbon fibers and a resin, the method comprising: providing a furnace comprising at least a heating portion; providing a transporter for transporting the composite material through the furnace; loading the composite material on the transporter and transporting the composite material through the furnace; detecting a percentage of oxygen in an atmosphere in the heating portion when the composite material has entered this portion; and removing resin from the composite material, as it travels through the heating portion of the furnace on the transporter, by means of chemical decomposition at a first temperature, with the resultant generation of fumes; wherein the generated fumes are removed from the heating portion in a controlled manner, such that the percentage of oxygen in the atmosphere in the heating portion is controlled.

Abstract: A coupled electrochemical system and method for its use is disclosed, where a polyol feed, especially a biomass polyol containing feed is reduced in a reducing solution including HI and a metal ion capable of converting I2 to HI during polyol reduction to hydrocarbon or iodohydrocarbon products and where the metal ions are capable of electrochemical reduction so that the system can be run on a batch, semi-continuous or continuous basis. The system is capable of producing hydrocarbon solvent, fuels and lubricating oils.

Abstract: A system and method for recycling plastics. The system and method recover materials such as hydrocarbon gases, liquid hydrocarbon distillates, various polymers and/or monomers used to produce the original plastics. The system and method allow about one unit of input of energy input to the plastic recycler to be used to create one or more gaseous components and one or more liquid distillate components from a plastic that is being recycled. The one or more gaseous components and one or more liquid distillate components produce about one corresponding unit of useable output energy recovered from the recycling of the plastic.

Abstract: Apparatus and process for producing hydrocarbon materials from a feed composition, the apparatus including a feed port; a viscous shear apparatus; a thermal decomposition assembly including a ribbonchannel reactor which includes an inner heated hollow cylinder; an outer heated hollow cylinder, one of which is rotatable with respect to the other, both heated hollow cylinders providing heat to the feed composition to convert it to a vapor fraction and a solid residue fraction; low height flighting mounted with respect to the inner and outer heated hollow cylinders to move the feed composition through the thermal decomposition assembly; at least one vapor port for removing the vapor fraction; and at least one solids port for removing the solid fraction.

Abstract: Biogas is converted to a liquid fuel by passing the biogas through a liquid reaction medium that contains a petroleum fraction in the presence of a transition metal catalyst, and doing so at an elevated but non-boiling temperature.

Abstract: A process for producing olefins from a feedstock comprising a petroleum and non-petroleum fraction has been developed. The process comprises first pretreating the feedstock to remove contaminants such as alkali metals and then cracking the purified feedstock in a fluidized catalytic cracking (FCC) zone operated at conditions to provide C2-C5 olefins. Alternatively, the non-petroleum fraction can first be treated and then mixed with petroleum fraction to provide the feedstock which is then catalytically cracked.

Abstract: A method of decomposing waste plastics, organics, and particularly medical waste composed of a varieties of plastics is described.

Abstract: Fractional hydrocarbons are recovered from reclaimed plastic materials and/or from oily residues. The reclaimed plastic materials and/or residues are sorted according to type and compacted using a feed system (1,2,3,4) in the absence of air. Thereafter the compacted mass is fed to a melting tank (7) below the liquid level. There the compacted mass is heated, so that a separation occurs into a first liquid phase, a first gas phase and a residue fraction. Thereafter the liquid phase and the first gas phase are transported into an evaporation tank (20) in which a second liquid phase and a second gas phase are formed under continued heat input. The second liquid phase is transferred to a re-heater (23) and is additionally heated there under further heat input so that a third gas phase is formed.

Abstract: One embodiment of a method of recycling a plastic material includes heating a plastic material in a treatment chamber in incremental steps through a series of graduated temperature set points wherein each graduated temperature set point corresponds to a vaporization temperature of an individual by-product of said plastic material, and pulling a vacuum of inert gas on the treatment chamber at each temperature set point to selectively remove an individual by-product corresponding to the temperature set point.

Abstract: The present invention is generally directed to methods and systems for producing biofuels via biomass, waste plastic, and/or Fischer-Tropsch product feeds. Such methods and systems are an improvement over the existing art at least in that they are feed-tolerant (i.e., allow for variability) and provide an economy of scale, while typically retaining the environmental benefits associated with such processing of such feeds.

Abstract: A system for treating a feedstock for the purposes of waste destruction, energy generation, or the production of useful chemicals is disclosed and includes a reactor vessel. A heating lance is configured to outflow the products of a partial oxidation reaction into a reaction chamber in the vessel. The hot reaction products heat and pyrolyze the feedstock in the chamber generating a process effluent which typically includes gases (e.g. syn-gas) and carbon solids. Glasses and metals in the feedstock accumulate in the chamber in a molten state. The molten materials store thermal energy and provide thermal stability to the treatment system. A recycle loop uses carbon solids from the process effluent as an input to the lance for reaction with an oxidant therein.

Abstract: This invention is about a continuously cracking technology of waste rubber or plastics and its realizing equipment, which is the key technology to produce oil by use of waste rubber or plastics. The cracking process is as following: the catalyst and rubber or plastics are extruded and transported in order to separate the air or to prevent oxidization; the raw materials are transported into the cracking chamber and moved from the inlet orifice to the discharge hole; the cracking process of the raw material is finished; and finally the products are deviated automatically through the discharge hole. In this invention, the separation of air and oxygen in the inlet orifice and discharge hole of the cracking chamber can completely avoid the hidden dangers caused by incoming of oxygen into the cracking chamber, and thus realize industrial production with continuous feedings. Moreover, the ratio of the oil can be raised from 19% in current technology to 45%-48%, and the loss of production equipment can be reduced.

Abstract: A method of producing high value products: kerosene including cosmetic kerosene, white oils, high value paraffin and purified liquid fuels, from polyolefin waste material and polyolefins, comprising (a) thermally or catalytically decomposing polyolefin waste material or polyolefins to yield vapor products; (b) condensing vapor products of thermal or catalytic decomposition of polyolefin waste material or polyolefins, to yield a first mixture; (c) catalytically hydrogenating said first mixture to reduce olefinic double bonds and acetylenic triple bonds to yield a second mixture; and (d) fractionally distilling said second mixture to yield one or more of the following: a kerosene fraction having a boiling range below 180° C., a cosmetic kerosene fraction having a boiling range of between 180 and 275° C., a white oil fraction having a boiling range of between 270 and 400° C., or a paraffin fraction having a boiling range above 400° C.

Abstract: An oil reconversion devices 1a and 1b for waste plastics which thermally crack a waste plastic Ro by heating it and converts a generated cracker gas Gr into oil by cooling it, equipped with a thermal cracking bath 2 which has a bath main body 4 placed inside a coil 3 . . . , induction-heats the bath main body 4 by feeding a high-frequency current through the coil 3 . . . , and thermally cracks at least a molten plastic Rd obtained from the waste plastic Ro to generate the cracker gas Gr, an injection port 5 through which the waste plastic Ro is injected, a feeder 6 which supplies the waste plastic Ro injected through this injection port 5 to the thermal cracking bath 2 via a forced or direct feeding means Ua or Ub without a bath, and an oil conversion processor 7 which cools and converts the cracker gas Gr generated by the thermal cracking bath 2 into oil.

Abstract: The present invention addresses the processing of waste and low-value products that contain bone material to produce useful materials in reliable purities and compositions, at acceptable cost, and with high energy efficiency. In particular, the invention comprises a process that converts various feedstocks such as offal, animal manures, and municipal sewage sludge, to useful materials including gas, oil, specialty chemicals, and carbon solids. The process heats the feedstock in order to breakdown proteins and separate organic material from bone material, applies further heat and pressure to the resulting liquid mixture, separates out various components, then further applies heat and pressure to one or more of those components. The invention further comprises an apparatus for performing a process of converting waste products into useful materials, and an oil product that arises from the process.

Abstract: The present invention provides methods for decomposing and extracting compositions for the recovery of petroleum-based materials from composites comprising those petroleum-based materials, comprising subjecting the compositions and/or composites to microwave radiation, wherein the microwave radiation is in the range of from about 4 GHz to about 18 GHz. The present invention also provides for products produced by the methods of the present invention and for apparatuses used to perform the methods of the present invention.

Abstract: A method produces a hydrocarbonaceous fluid (a liquid mixture of hydrocarbons, or in other words a mixture of hydrocarbons which is liquid at ambient room temperature and atmospheric pressure), which functionally is a liquid hydrocarbon fuel, from a feed of waste plastic. The method comprises in broad embodiments the steps of: (step 1) melting a feed of substantially solid waste plastic in an aerobic atmosphere (for instance, air) whereby a waste-plastic melt is produced; (step 2) distilling at least a portion of the waste-plastic melt whereby a hydrocarbonaceous distillate is produced; and (step 3) collecting the hydrocarbonaceous distillate. That distillate is generally referred to above as a condensate. In some preferred embodiments, the method includes the step of commutating the feed of substantially solid waste plastic into pieces substantially no greater than about 1.5 cm2 prior to step 1.

Abstract: A system and method for recycling plastics. The system and method recover materials such as hydrocarbon gases, liquid hydrocarbon distillates, various polymers and/or monomers used to produce the original plastics. The system and method allow about one unit of input of energy input to the plastic recycler to be used to create one or more gaseous components and one or more liquid distillate components from a plastic that is being recycled. The one or more gaseous components and one or more liquid distillate components produce about one corresponding unit of useable output energy recovered from the recycling of the plastic.

Abstract: A method and apparatus for the continuous recycling of hydrocarbon containing used and waste materials such as plastic and polymeric waste including, for example, polyurethane, rubber wastes and the like, and in particular scrap rubber tires, are disclosed. The process is carried out under moderate temperatures and atmospheric pressure in the presence of air and a feed of liquid(s) containing oxygen. The method is characterized by the low residence time.

Abstract: A method including mechanically breaking a source substance including relatively long carbon chains so as to produce a product comprising shorter chain carbon molecules.

Abstract: The present invention provides a method of recycling a plastic thereby forming a narrow spectrum of hydrocarbons having from 4 to 14 carbon atoms that can be directly used as gasoline without additional processing or refining. The method includes the step of feeding the plastic, selected from the group of polyethylene, polypropylene, polystyrene, and combinations thereof, into a heated vessel for melting. The method also includes the step of decomposing the plastic at a temperature of from 400° C. to 500° C. in the presence of a metallocene catalyst and a zeolitic catalyst thereby forming the hydrocarbons having from 4 to 14 carbon atoms. The metallocene catalyst includes dichlorobis(2-methylindenyl)zirconium (IV). The zeolitic catalyst includes ammonium Y zeolite and has a pore size of from 1 to 4 Angstroms.

Abstract: A plug flow reactor having an inner shell 27 surrounded by outer shell 21 and having at least one annular flow passage 35 therebetween can be used to prepare compositions, including polymers. The plug flow reactor also includes inlet port 36, an outlet port 37 and a plurality of exchanger tubes 26 wherein the exchanger tubes are in fluid communication to the at least one annular flow passage. Polystyrene and high impact polystyrene can be prepared using the reactor.

Abstract: A process has been developed for producing a hydrocarbon component useful as diesel fuel from biorenewable feedstocks such as plant oils and greases. The process involves hydrogenating and deoxygenating, i.e. decarboxylating and/or hydrodeoxygenating the feedstock to provide a hydrocarbon fraction useful as a diesel fuel. An optional pretreatment step to remove contaminants such as alkali metals from the feedstock can also be carried out. If desired, the hydrocarbon fraction can be isomerized to improve cold flow properties.

Abstract: Conversion of waste and other organic feedstock into sustainable energy, feed, fertilizer, and other useful products of reliable purities is accomplished using water, heat, and pressure. More specifically, the invention provides methods and apparatus that handle mixed streams of various feedstocks, e.g. agricultural waste, biological waste, municipal solid waste, municipal sewage sludge, and shredder residue, to yield gas, oil, specialty chemicals, and carbon solids that can be used as is or are further processed. Useful products can be diverted at various points of the process or internalized to enhance the efficiency of the system.

Abstract: A system and method for recycling plastics. The system and method recover materials such as hydrocarbon gases, liquid hydrocarbon distillates, various polymers and/or monomers used to produce the original plastics. The system and method allow about one unit of input of energy input to the plastic recycler to be used to create one or more gaseous components and one or more liquid distillate components from a plastic that is being recycled. The one or more gaseous components and one or more liquid distillate components produce about one corresponding unit of useable output energy recovered from the recycling of the plastic.

Abstract: The present invention discloses a method of utilizing a catalytic reaction to recycle organic scrap, wherein via a special cracking equipment, a special catalyst and a two-stage cracking process, the present invention not only can effectively convert organic scrap into regenerated oil but also can promote the yield and quality of the regenerated oil; further, the method of the present invention can overcome environmental problems and has the characteristics of high safety, high stability, and high economic efficiency.

Abstract: A pyrolysis process and reactor converts various hydrocarbons such as waste materials, for example, scrap polymers, tires, etc., into various chemical components or amounts thereof, not otherwise produced by conventional pyrolytic processes. A large reactor size is utilized in association with a low heat input per unit weight of charge. A thick pyrolyzate/“char” layer is formed during pyrolysis. The product or various components thereof can be utilized as a fuel or octane additive.

Abstract: A method including mechanically breaking a source substance including relatively long carbon chains so as to produce a product comprising shorter chain carbon molecules.

Abstract: The present invention provides a pyrolysis system and method thereof which are capable of converting an entire rubber tire into several energy resources in an environmentally-friendly manner. The system includes a tire transporting unit, a waste to energy conversion unit, and a energy collection unit. The waste to energy conversion unit includes a conversion housing having a reaction chamber for receiving the rubber tire for pyrolysis processing to decompose the rubber tire into fuel oil, methane gas and carbon black, while metal wire from the rubber tire are resided for recycling use.

Abstract: A method and apparatus for the continuous recycling of hydrocarbon containing used and waste materials such as plastic and polymeric waste including, for example, polyurethane, rubber wastes and the like, and in particular scrap rubber tires, are disclosed. The process is carried out under moderate temperatures and atmospheric pressure in the presence of air and a feed of liquid(s) containing oxygen. The method is characterized by the low residence time.

Abstract: A low energy method of pyrolysis of rubber or other hydrocarbon material is provided. The hydrocarbon material is heated while maintaining a vacuum, using a clay catalyst. In an additional embodiment, also under a vacuum and optionally with or without the catalyst, the temperature of the reaction chamber and corresponding fuel input is varied either over time or spatially within the reaction chamber, to take advantage of the exothermic properties of the reaction. With the method of the present invention, an improved solid reaction product can be achieved.

Abstract: Plant for the production of combustible substances by means of depolymerisation of rubber products, comprising a depressurized depolymerising device (1), inside which it takes place the depolymerisation of a predetermined quantity of products introduced at its inner, characterized in that it comprises a divider or phases separator (2) disposed downstream said depolymerising device (1), which consists of a substantially cylindrical body, with an upper base (20) and a lower base (21), and is connected with the depolymerising device (1) by means of a pipe (3): said phases separator (2) being apt to carry out the separation of at least a part of the liquid phase of the products exiting the depolymerising device (1), and having an outlet (23) for the thus separated liquid phase and an outlet (24) for the remaining part of the products in mostly gaseous phase.

Abstract: Method for utilization of rubber wastes with simultaneous carrying of pyrolysis of coal in cells of a coke oven battery, in which each consequent cell is filled with previously prepared and disintegrated blend of coke coals of a size of particles 0.1-5.0 mm in amount of 95-99% by weight a rubber granulate is added in a form of a rubber grain of a size of particles 0.1-5.0 mm in amount of 1-5% by weight, and thus formed mixture of coking coals charge and rubber grain is thickened by a mechanical compacting till an uniform structure of a whole charge is obtained, and then a process for utilization of rubber wastes is carried out in a closed system without an access of oxygen in a temperature of at least 900° C. with a simultaneous pyrolysis of coal.

Abstract: A method is disclosed for reforming organics into shorter-chain unsaturated organic compounds. A molten metal bath is provided which can cause homolytic cleavage of an organic component of an organic-containing feed. The feed is directed into the molten metal bath at a rate which causes partial homolytic cleavage of an organic component of the feed. Conditions are established and maintained in the reactor to cause partial homolytic cleavage of the organic component to produce unsaturated organic compounds, as products of the homolytic cleavage, which are discharged from the molten metal bath.