Fuel handling system

Liquid fuels require atomization and treatment to inhibit sodium and vanadium content. Liquid fuels can drastically reduce the life of a unit if not properly treated. A typical fuel system is shown in Figure 4-7. The effect of fuels on gas turbines and the details of types of fuel handling systems is given in Chapter 12. 

The gas turbine is a complex system. A typical control system with hierarchic levels of automation is shown in Figure 19-3. The control system at the plant level consists of a D-CS system, which in many new installations is connected to a condition monitoring system and an optimization system. The D-CS system is what is considered to be a plant level system and is connected to the three machine level systems. It can, in some cases, also be connected to functional level systems such as lubrication systems and fuel handling systems. In those cases, it would give a signal of readiness from those systems to the machine level systems. The condition monitoring system... 

The majority of today s turbines arc fueled wth natural gas or No. 2 distillate oil. Recently there has been increased interest in the burning of nonstandard liquid fuel oils or applications where fuel treatment is desirable. Gas turbines have been engineered to accommodate a wide spectrum of fuels. Over the years, units have been equipped to burn liquid fuels, including naphtha various grades of distillate, crude oils, and residual oils and blended, coal-derived liquids. Many of these nonstandard fuels require special provisions. For example, light fuels like naphtha require modifications Co the fuel handling system to address high volatility and poor lubricity properties. 

NOTE Where the primary problem is to improve combustion efficiency, the product typically is added to the fuel handling system via an automatic feeder and used continuously at a rate of 0.5 and 1.5 lb per ton of fuel. 

It is also toxic and a few teaspoons of methanol consumed orally can cause blindness. A few tablespoons can be fatal, if not treated. Methanol is also very corrosive, so it requires a special fuel-handling system. 

Harada and Mori, 1988 Yamamoto, Kaneko and Takahashi, 1988). The system consisted of a SOFC generator module containing 144 cells, electrical air preheaters for generator temperature control and an air and fuel handling system. The system operated continuously and successfully for over six months. Now, 25 kW scale SOFC systems from Westinghouse are being tested. 

Fuel-handling systems (diaphragms for fuel pumps, see Figure 5.5, fuel hose or fuel hose liner, inject or nozzle seals, needle valves, filter casing gaskets, fuel shutoff valves, carburetor parts)... 

The presence of surfactants can also impair the performance of the water-separating equipment (filter/separators) widely used throughout fuel handling systems to remove the traces of free (undissolved) water, particularly at the later stages before delivery to aircraft. Very small traces of free water can adversely affect jet engine and aircraft operations in several ways, and the water retention and separating properties of jet fuels have become a critical quality consideration in recent years. 

In gas turbine fuel, sulfur compounds (ASTM D-2880 notably hydrogen sulfide, elemental sulfur, and polysulfides) can be corrosive (ASTM D-130, IP 30) in the fuel handling systems and mercaptans can attack any elastomers present. Thus mercaptan sulfur content (ASTM D-235, ASTM D-3227, IP 30, IP 104) is limited to low levels because of objectionable odor, adverse effects on certain fuel system elastomers, and corrosiveness toward fuel system metals. 

European Standard EN 746-2. Industrial thermoprocessing equipment Part 2 Safety Requirements for Combustion and Fuel Handling Systems, March 1997. 

A correlation for parasitic power for a wood-fired power plant was developed from a correlation for coal-fired plants given in the literature (88) and an analysis of the relative amounts of power used in the fuel-handling system... 

Over a total period of operation the core sub-assembly cleaning system performance was sufficiently reliable. Like with the fuel handling system it is the mechanism position indication and control system that has mostly been a trouble contributor with an impact from the process control and monitoring system. The process configuration itself is unsatisfactory since the manifold of the steam-water cleaning cells is combined with the equipment cleaning system (large capacities, risk of overflows and leaks, etc...). 

The pneumatic pulse singulizer for discharging the spherical fuel elements from reactor core is used in the fuel handling system. 

The test components of the fuel handling system and the small absorber ball system, the prototype of the control rod driving apparatus and the test section of the hot gas duct are designed in 1 1 scale. It is planed to perform the experiments at the operation temperature and helium atmosphere conditions. The experiments of the fuel handling system and small absorber ball simulating system at ambient temperature had been carried out. 

The components of the fuel handling system, the helium purification system and other auxiliary systems will be also domestically made. 

The fuel-handling system designs for the EBR-II, FFTF, and CRBRP reflected the requirements imposed by the individual facility missions and reactor system designs. The EBR-II was intended as a developmental prototype for a breeder reactor power station. The FFTF was designed as an irradiation test facility for fuels and materials and the CRBRP was to be a medium-sized demonstration commercial breeder reactor power station. 

The EBR-II fuel-handling system is designed to facilitate loading of fresh fuel into the reactor and removal of SNF from the reactor to the adjacent fuel cycle facility (EBR-II, 1971 Koch). The fuelhandling system is displayed in Fig. 5.1, which shows the reactor, the fuel gripper, and the hold-down mechanisms, the transfer arm, the storage basket, and the fuel-unloading machine. 

A view of the general arrangement of the fuel-handling system is shown in Fig. 5.6. New fuel assemblies arrive at the plant in shielded and cushioned containers. They are unloaded and inspected in a shielded new fuel-handling facility located in the reactor service building (RSB). Upon acceptance of a core component, it is stored in a subcritical array in a storage facility located in the floor of the new fuelhandling facility. 

Refueling differences exist between sodium-cooled reactors and the AHTR. For the AHTR, refueling temperatures are somewhat higher, the fuel geometry is different, the power density of the prismatic-block fuel-type SNF is 1 to 2 orders of magnitude lower, the vapor pressures of the liquid salts are much lower than those of sodium, and the liquid salt is transparent whereas the sodium is opaque. This section provides discussions of design considerations for the LS-VHTR fuel-handling system relative to sodium-cooled fast reactors. 

EBR-II, 1971, EBR-II System Design Descriptions, Volume II, Chapter 5 Fuel Handling System, Argonne National Laboratory, Argoime, Illinois, June 15. 

This appendix provides a brief description of the Fast Flux Test Facility (FFTF) fuel handling system and its operation as described by Cabell (1980) and in the Fast Flux Test Facility System Design Description (FFTF, 1983). The description is limited to those system features that are potentially relevant to the refueling of a liquid-salt very high-temperature reactor (LS-VHTR). Because the FFTF was designed as a reactor to test fuel, it has additional capabilities and equipment compared with a sodium-cooled fast reactor designed only to produce electricity. 

---