Sulfur integrated testing

Table II indicates the four major areas to be treated in the overall development program. These are the Electrolyzer, Sulfur Trioxide Reduction, Integrated Testing, and Process Studies. The sections below describe the current status and the effort to be accomplished in each area for the duration of the program.

In addition, the KAERl-DySCo simulation code has been used for the dynamic startup simulations of a sulfuric acid distillation column, Hlx distillation column, and its thermal decomposers, which are the main components of an SI integrated test facility with a hydrogen production rate of 50 NL-H2/h. Fig. 13.18 shows 50NL-H2/h-scale SI test facilities built at KIER, which is under modihcation for improvements in its operational efficiency. 

EPA Method 6C is the instrumental analyzer procedure used to determine sulfur dioxide emissions from stationaiy sources (see Fig. 25-30). An integrated continuous gas sample is extracted from the test location, and a portion of the sample is conveyed to an instrumental analyzer for determination of SO9 gas concentration using an ultraviolet ( UV), nondispersive infrared (NDIR), or fluorescence analyzer. The sample gas is conditioned prior to introduction to the gas analyzer by removing particulate matter and moisture. Sampling is conducted at a constant rate for the entire test rim. 

A simplification of the polarization resistance technique is the linear polarization technique in which it is assumed that the relationship between E and i is linear in a narrow range around E . Usually only two points ( , 0 are measured and B is assumed to have a constant value of about 20 mV. This approach is used in field tests and forms the basis of commercial corrosion rate monitors. Rp can also be determined as the dc limit of the electrochemical impedance. Mansfeld et al. used the linear polarization technique to determine Rp for mild steel sensors embedded in concrete exposed to a sewer environment for about 9 months. One sensor was periodically flushed with sewage in an attempt to remove the sulfuric acid produced by sulfur-oxidizing bacteria within a biofilm another sensor was used as a control. A data logging system collected Rp at 10-min intervals simultaneously for the two corrosion sensors and two pH electrodes placed at the concrete surface. Figure 2 shows the cumulative corrosion loss (Z INT) obtained by integration of the MRp time curves as ... 

In order to explore composition modulation of the final stage of a converter further, Briggs et al. (1978) added a second integral reactor, also holding about 30 g of the vanadia catalyst. With the preconverter in place, this system was operated on a typical feed from sulfur burning, with a S02 02 N2 composition in vol% of 10.8 15.2 74, and from a smelter effluent with a composition of 8.0 6.2 85.8. The cycled beds of vanadia catalyst were held in a fluidized sand bath at 401°C for the former feed and at 405°C for the latter one. The space velocity for both the air and the S03/S02 mixture was about 24 min 1 (STP). Table II summarizes the experimental results for the cycle periods tested. 

During operation of the loop, small quantities of sulfur were observed in the recycled liquids from the HI cracking coolers and small amounts of H2S were collected in the H2 purification traps. This was due to incomplete separation of the sulfur containing species (SO2 and H2SO4) from the lower phase prior to decomposition. The lower phase concentration and purification step (H3PO4 treatment), which is an integral part of the cycle, will eliminate this problem. This step will be tested in the Bench Scale Unit. 

The sulfur foams for these tests were foamed-in-place with pilot field equipment at a foaming rate of 100 lb/min. Installation, instrumentation, and performance of these tests have been reported in detail (1,2). Field surveillance data and sample analysis over two years so far indicate design insulation effectiveness and property integrity (Figures 1 and 2, Table I). 

In addition to the problems associated with excessive mixing and compaction, a series of tests was designed to illustrate the extent to which the structural integrity of the S-A-S material would be affected by a loss of process control. The two operational problems simulated were material handling below the solidification temperature of the sulfur (240° F) and a loss of temperature control at the hot-mix plant, causing a temperature rise above 320°F. 

The integrated results of these individual runs have proved that the system is practical for large scale operations and can treat a variety of sulfur dioxide-rich effluent gases. The completed pilot test program has demonstrated that 90% of the sulfur dioxide in a typical feed gas can be converted to elemental sulfur in a prototype apparatus having design features compatible with commercial requirements. 

The STAR fuel processor represents a culmination of three years of intensive R D and design efforts. Prior to their use in the integrated fuel processor, all components were tested in the MPR. Figure 4 compares the expected and obtained performance of the water-gas-shift catalyst in the MPR. Similarly, the MPR testing validates the desulfurizer performance data collected on the bench scale reactor (Table 2). The sulfur capacity was the same in both the MPR and the bench scale reactor. 

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