Turbine running

Fully Catalytic Design la Mid- and iMrge-size Gas Turbines Running on LNG - The first design has been proposed by Sadamori et al. and is a cooperation between Osaka Gas, Kobe Steel, and Catalyst and Chemicals Inc. Here, all fuel is mixed together with the preheated air at the inlet of the... 

Note, that 1 atm is an important pressure. Almost all combustion systems run in ambient air at 1 atm. Some scram jet engines run at 0.3 atm, and turbines run at pressure of 10 - 15 atm. It is general that data are illustrated and discussed for 1 atm pressure. Also most experiments run at... 

The BFW preparation unit is associated with the power station. It is a full demineralization unit producing a BFW quality as required for a boiler operating at 120 bar. The power station service pump is driven by a condensation turbine running on 120 bar steam. The stand-by pump is driven by an electric motor, which can be automatically started up mote easily than a steam turbine. 

Other training programmes on the simulator include reactor shutdown, on-load refuelling and turbine run-up, as well as abnormal or fault situations, including the loss of auxiliary plant with the reactor at power, such as ... 

Most of the developments in the SCSA process were followed for the DCDA process with provision of WHRB and economisers along with steam superheaters to generate the maximum amount of steam. It was possible to produce power or to run the blower with the turbine running on the HP superheated steam. The exhaust steam was used for process heating—smelting of sulfur, evaporation of dilute alum/ phosphoric acid solutions/ for multiple effect evaporators, etc. ... 

For the MP header, steam input comes from the process-fired heater F-5001 where the radiation section is used for process feed heating, while the convection section for MP steam generation. MP steam is also made from the extraction of CT-1401 turbine, the HP letdown, and two WHBs. On the other hand, MP steam is used as column reboiling and stripping as well as in the steam turbines and MP letdown. CT-1601 turbines run a compressor and boiler PTs include four small turbines used for running a boiler water circulation pump and three AD fans. Since MP letdown is not measured, it is unknown and to be determined together with the MP imbalance. The MP imbalance includes metering error, steam losses due to steam traps, leaks, and so on. Table 16.10 shows the balance for the MP header. 

Below that speed it operates as a motor and takes power from the grid. This motor/generator is used because the turbine takes some time to build up to a speed where it can generate electricity. When the turbine slows down due to a lull in wave activity, the generator becomes an electric motor and keeps the turbine running at a 20 minimum speed so that it is ready to accept the power from the next batch of waves. 

When steam enters a turbine through the nozzle block, its pressure energy is converted to velocity energy. This is an isoentropic expansion, in that the potential of the steam to do work is preserved. When a turbine runs too fast, it may be slowed down in one of two ways. First, allow the governor steam inlet valve to reduce the flow of steam. Not only is the steam flow reduced, but the pressure of the steam flowing into the nozzle block, hence its ability to do work, is diminished. The other way is to reduce the nozzle block cross-sectional area by closing one or more hand valves. This simply reduces the flow of steam but does not impair the ability of the steam to do work. 

Air intake filters plugged Pressure restriction of blower discharge Increased ambient temperature Compressor rotor fouled Blower turbine running slow Wet gas compressor problems Fractionator condensers plugged... 

Figure 3.18 Two-stage RO system with turbine running on first-stage concentrate.

Some gas turbines run on many different kinds of fuel—gas, diesel, and residual fuel. The life of their hot-section components will be very different, depending on the type of fuel they are nmning. Natural gas is generally a clean fuel and causes the least toll in parts life in a gas turbine. 

Electrical power is supplied to MWD tools either from batteries run in the downhole assembly or from an alternator coupled to a turbine set in the mudstream. 

Spare pump begins to cavitate when attempt is made to switch it with the running pump. The spare is backed off by the running pump because its shutoff head is less than the head produced by the running pump. This is a frequent problem when one pump is turbine-driven and one is motor-driven. 

Throttle discharge of running pump until spare can get in system. Slow down running pump if it is a turbine or variable-speed motor. 

Foam can also be broken with a rotating perforated basket [Lem-lich, Principles of Foam Fractionation, in Periy (ed.), Progre.ss in Separation and Purification, vol. 1, Interscience, New York, 1968, chap. 1]. If the foamate is aqueous (as it usually is), the operation can be improved by discharging onto Teflon instead of glass [Haas and Johnson, Am. In.st. Chem. Fng. J., II, 319 (1965)]. A turbine can be used to break foam [Ng, Mueller, and Walden, Can. J. Chem. Fng., 55, 439 (1977)]. Foam which is not overly stable has been broken by running foamate onto it [Brunner and Stephan, Ind. Fng. Chem., 57(5), 40 (1965)]. Foam can also be broken by sound or ultrasound, a rotating disk, and other means [Ohkawa, Sakagama, Sakai, Futai, and Takahara,y. Ferment. Technol, 56,428, 532 (1978)]. 

Leaky valves are also a cause of erosion. Most turbine erosion-corrosion problems come from damage that takes place when the unit is not running. A shght steam leak into the turbine will let the steam condense inside the turbine, and salt from the boiler water will settle on the inside surfaces and cause pitting, even of the stainless blading. There must be two valves with a drain between them, i.e., a block valve on the header and an open drain in the line before it reaches the closed trip-throttle valve. 

In a turbine that is running, erosion-corrosion is pretty much confined to units that are operating on saturated steam with inadequate boiler-water treatment. This type of erosion takes place behind the nozzle ring and around the diaphragms where they fit in the casing. 

The gas turbine in the simple cycle mode consists of a compressor (axial or centrifugal) that compresses the air, a combustor that heats the air at constant pressure and a turbine that expands the high pressure and high temperature combustion gases and produces power to run the compressor and through a mechanical coupling to the driven equipment. The power required to compress the gases varies from about 40-60 percent of the total power produced by the turbine. 

Since the exacd value of the hydraulic efficiency e, is never known, V/ can be taken as an approximation where e is the gross (hydraulic horsepower/brake horsepower) pump efficiency. Efficiencies of pump designs running as turbines are usually 5 to 10 efficiency points lower than those as pumps at the best efficiency point. 

These motors have a lower efficiency as a result of running in liquid, causing more liquid drag and also axial thrust bearing loss, which is also a part of the motor. However, this lower efficiency of the motor is compensated by fewer mechanical and hydraulic losses in a submersible motor-pump installation, compared to a vertical turbine pump installation. 

The work required to drive the turbine eompressor is reduced by lowering the compressor inlet temperature thus increasing the output work of the turbine. Figure 2-35 is a schematic of the evaporative gas turbine and its effect on the Brayton cycle. The volumetric flow of most turbines is constant and therefore by increasing the mass flow, power increases in an inverse proportion to the temperature of the inlet air. The psychometric chart shown shows that the cooling is limited especially in high humid conditions. It is a very low cost option and can be installed very easily. This technique does not however increase the efficiency of the turbine. The turbine inlet temperature is lowered by about 18 °F (10 °C), if the outside temperature is around 90 °F (32 °C). The cost of an evaporative cooling system runs around 50/kw. 

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