Molten process pilot plant

Molten carbonate process pilot plant at completion of construction, Mar. 30,1973... 

Still another process, called BI-GAS, was developed by Bituminous Coal Research in a 73 t/d pilot plant in Homer City, Peimsylvania. In this entrained-bed process, pulverized coal slurry was dried and blown into the second stage of the gasifier to contact 1205°C gases at ca 6.9 MPa (1000 psi) for a few seconds residence time. Unreacted char is separated and recycled to the first stage to react with oxygen and steam at ca 1650°C to produce hot gas and molten slag that is tapped. 

The Japanese Direct Iron Ore Smelting (DIOS) process. This process produces molten iron directly with coal and sinter feed ore. A 500 ton per day pilot plant was started up in October, 1993 and the designed production rates were attained as a short term average. Data generated is being used to determine economic feasibility on a commercial scale. 

HIsmelt A direct iron smelting process in which noncoking coal, fine iron ore, and fluxes and gases, are injected into a molten iron bath the carbon monoxide produced is used to prereduce the ore in a fluidized bed. Under development by CRA, Australia, since the early 1980s, joined by Midrex Corporation in 1988. Their joint venture company, Hismelt Corporation, commissioned a pilot plant at Kwinana, near Perth, Australia, in 1993. 

Other reactors and processes include the hot oil bath, molten salt bath, microwave, and plasma. These processes have been researched on laboratory and some cases pilot plant scale. None have proven commercially successful. 

In the molten carbonate process a molten eutectic mixture of lithium, sodium, and potassium carbonates removes sulfur oxides from power plant stack gases. The resulting molten solution of alkali metal sulfites, sulfates, and unreacted car bonate is regenerated in a two-step process to the alkali carbonate for recycling. Hydrogen sulfide, which is evolved in the regeneration step, is converted to sulfur in a conventional Claus plant. A 10 MW pilot plant of the process has been constructed at the Consolidated Edison Arthur KiU Station on Staten Island, and startup is underway. 

Based on available information, we believe that transfer of the uranate to a molten chloride system with electrolytic reduction is the most feasible method. Electrolytic deposition from molten alkali metal chlorides was an integral step in the pyro-chemical process known as the Hanford Salt Cycle. Documentation of this phase of the process was extensive and also represents one of the very few pyrochemical processes that has been carried through pilot-plant scale on irradiated fuel. Unknowns exist, such as the rate and conditions of uranate dissolution, but considerable use could be made of previously documented results. 

This molten salt gasification process is the basis for the Rockwell International molten salt coal gasification process. A 900-kg-h l (1 ton/h) process development unit pilot plant has been built and is being tested under contract from the Department of Energy. This plant includes the gasifier and a complete sodium carbonate recovery and regeneration system. 

As usual in the conventional copper or lead smelter, none of the El Paso smelter gas streams has a sulfur dioxide concentration as high as 12%. In the pilot plant, then, the 12% sulfur dioxide gas stream is generated by burning molten sulfur in a spray-type sulfur burner to produce a gas stream containing 18% sulfur dioxide. This hot gas stream, at 1350°C (1623 K), is cooled to about 360°C (633 K) in a waste heat boiler. When the pilot plant is operating with this 18% gas, process tail gases are recycled to dilute the 18% head gas stream to 12%. In an alternate mode of operation, liquid sulfur dioxide is vaporized to generate the pure gas. 

In contrast to the silicon process, durable electrorefining of Mb and Ta was more successful. The processes were performed in the molten mixture KCl-NaCl-K2NbF7 (K2Tap7) at 720 10 °C in course of 1 or 2 weeks. Two different types of electrolysers were used, i.e., laboratory type and pilot plant cells, enabling operating currents up to 50 and 300 A, respectively. The techniques, other conditions and results of the experiments were described in detail in [12]. 

For several years TVA produced calcium metaphosphate, Ca(POs)2, in a demonstration-scale plant. The process consisted of burning elemental phosphorus and reacting the resulting P2O5 vapor with phosphate rock. The molten product was tapped out of the ftirnace and -solidified on a watei cooled steel drum [17]. The resulting vitreous flakes were cooled further and crushed to pass a 10-mesh screen (about 1.6 mm). Development of a process for production of calcium metaphosphate involved three pilot plants and three demonstration-scale plants and a considerable amount of laboratory- and bench-scale work [IS]. The third demonstration-scale plant was technically successful and operated about 16 years, starting in 1949. A total of nearly 1 miflion tonnes was produced, including relatively small amounts from the first and second demonstration-scale plants. The process was economically competitive with TSP when both products were based on elemental phosphorus made by the electric-furnace process. 

Kloeckner/CRA Process (29). The Kloeckner/CRA molten-iron bath coal gasification process was originally very similar to the KHD process. However, developers have modified it for use in a new iron making process called HIselt being developed by CRA and Midrex. A large pilot plant is under construction in western Australia. It is likely that this process could produce excess coal-derived fuel gas like the COREX process. 

AECI Ltd. of South Africa built a pilot plant for recycling of polymethyl methacrylate (PMMA) and using it in production of acrylic sheet. The process uses microwaves to de-polymerize PMMA through thermal decomposition, and replaces existing molten-bath recycling reactors. 

The Mivida SulFerox unit is designed for about 2 LT/day sulfur production and includes a sulfur melter to process the SulFerox sulfur filtercake for sale as a high quality molten product. A flow diagram of the sulfur melter is shown in Figure 9-44. A summary of the projected operating conditions at the Mivida SulFerox plant, which includes a mix of SulFerox pilot plant and design data, is provided in Table 9-22 (Iversen et al., 1990 Allen, 1995). 

On the basis of laboratory work of Morell and co-workers, a pilot plant was set up for further study of the pyrolysis step. Results are reported by Schniepp, Dunning, Geller, Morell, and Lathrop (115). The equipment consisted essentially of a metal pyrolysis coil in a bath of molten lead for the main step of the process. Vapors from the coil were cooled rapidly in a quench chamber and passed through a packed column where acetic acid and other liquid pyrolysis products were washed out. The butadiene gas was scrubbed, dried, compressed, and finally condensed to liquid for collection and weighing. It is interesting at this point to note the pilot plant recoveries tabulated by Schniepp and co-workers. These are given below as over-all recoveries of butadiene from the glycol. 

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