Auxiliary equipment

A wide range of auxiliary equipment has been developed for gas-cooled reactors, including appropriate control and instrumentation systems, control rods and drives, and coolant handling and purification systems. The developments in these areas are too varied to report in detail here. However, it may be of interest to note some of the principal developments in control equipment and coolant purification equipment for the magnox, AGR, HTGR, and related plants. 

The control rods used in the magnox reactor plants are solid boron steel rods sheathed in stainless steel. They are suspended by flexible steel cables and are lifted from the core by control-drive drums and motors or, in the case of the concrete pressure vessels, above the reactor core but inside the vessel. The cable-driven rods depend on gravity for shutdown insertion, and, therefore, the clearance between the control rod 

The EGCR and the Windscale AGR also use cable or chain-driven control rods. The AGR control rods (50) are 4% cast boron steel rods sheathed in a stainless-steel tube having an outside diameter of in. The control rod is lifted by a chain drive and operates in a control channel having an inside diameter of 5 in. The EGCR control rod (57) contains B4.C absorber sections in a stainless-steel tube having an outside diameter of 3 in. and is operated in a channel 4 in. in diameter. The control rod is articulated to allow it to operate even in a bowed channel. The rod is operated by a drum and cable mechanism. 

The 330 MWe HTGR is designed to use simple cable-operated control rods. The compact arrangement of a cable-driven control rod is particularly desirable for plants using a concrete pressure vessel. 

Coolant handling and purification systems for gas-cooled reactors have been developed to meet the requirements of the several types of gas-cooled reactors. 

Product blending kits are available by some equipment vendors for factory installation. These kits allow for bypass of a prescribed amount of influent water into the permeate line. The kit includes check and butterfly valves, a rotameter, and all fittings. 

Fraction collectors allow automatic collection of the effluent and are the first to be applied in preparative gel chromatography. The shift of the collecting vials is controlled by the impulses from the device responding to the change of their weight, from the volumeter, from the timer or from the peak-slope detector. 

Thermostats control the temperature of the whole apparatus or its particular parts. Thermostats are used in GPC measurements of high precision, or in the case when it is necessary to perform the separation under reduced or elevated tempera- 

Registration devices for the registration of detector response in the instruments of the second and third generations, potentiometric recorders are most often used. The primary as well as integrated and otherwise processed data in the instruments of the fourth generation are registered by printer-plotter devices. 

---

Prior to moving the rig and all auxiliary equipment the site will have to be cleared of vegetation and levelled. To protect against possible spills of hydrocarbons or chemicals the surface area of a location should be coated with plastic lining and a closed draining system installed. Site management should ensure that any pollutant is trapped and properly disposed of. 

Specifying operating conditions, control methods, and auxiliary equipment to meet the technological and economic needs of the reaction process... 

Auxiliary Equipment On direct-heat rotating equipment, a combustion chamber is required for high temperatures and finned steam coils are used for low temperatures. If contamination of the produc t with combustion gases is undesirable on direct-heat units, indirect gas- or oil-fired air heaters may be employed to achieve temperatures in excess of available steam. 

Figure 16-49 [Engineering Data Book, 10th ed., Gas Processors Slippers Association, Tulsa, 1988, Sec. 20, p. 22] depicts the flow scheme for a typical two-bed TSA dryer system showing the auxiliary equipment associated with regeneration. Some of the diy product gas is externally heated and used couutercurreutly to heat and desorb water from the adsorber not currently drying feed. The wet, spent regeneration gas is cooled the water is condensed out and the gas is recycled to feed for recovery.

Important auxiliary equipment in a flotation plant includes feeder and controls, sampling and weighing devices, slurry pumps, filter and thickeners for dewatering solids, reagent storage and makeup equipment, and analytical devices for process control. 

Auxiliary Equipment Elevating conveyors must be equipped with some form of holdback or brake to prevent reversal of travel and subsequent jamming when power is unexpectedly cut off. Ratchet and wedge roUer-type holdbacks are commonly used. Solenoid brakes and spring clutches may also be employed. 

Waste category Container Auxiliary equipment and conditions of use... 

Incorrect electrical classification for equipment or auxiliary equipment, lighting, etc., possibly leading to unsafe conditions. 

Is the new hazard due to shared or auxiliary equipment associated with the toll ... 

Safety systems are typically divided into emergency trip/shutdown functions, controlled (slow) shutdown, alarm activation, or startup annunciation of auxiliary equipment such as oil pumps. 

All instrument tubing and subsystem piping should be arranged to allow free aeeess to expander and major auxiliary equipment for operation and maintenanee. 

Lube oil level in the reservoir should be monitored by a sensing deviee to indieate low lube oil level. Loeal and panel-mounted pressure gauges are neeessary to monitor operation of the lube oil system and must be ineluded in the manufaeturer s seope of supply. The purehaser must distinguish between eontrol room instrumentation and instruments mounted on a stand-alone (loeal) panel. There is also a tendeney to plaee monitoring instruments on auxiliary equipment and piping. While this may eost less, it often eomplieates tlie operator s surveillanee tasks. 

Other suggestions that address gas flow deviation include a retrofit of the stator-nozzle assembly or replacing rotors with shorter blades. However, it is easier to increase volume flow by lowering inlet pressure. Increased capacity of the third-stage separator and the auxiliary equipment avoids the possibility that excess catalyst will pass through the equipment. 

ASME Procurement Standard for Gas Turbine Auxiliary Equipment B133.3 (Published 1981) (Reaffirmed Year 1994)... 

This standard could be adapted to the fuel compressor for the natural gas to be brought up to the injection pressure required for the gas turbine. Covers the minimum requirements for reciprocating compressors and their drivers used in petroleum, chemical, and gas industry services for handling process air or gas with either lubricated or nonlubricated cylinders. Compressors covered by this standard are of moderate-to-low speed and in critical services. The nonlubricated cylinder types of compressors are used for injecting fuel in gas turbines at the high pressure needed. Also covered are related lubricating systems, controls, instrumentation, intercoolers, after-coolers, pulsation suppression devices, and other auxiliary equipment. 

The balance chamber leakoff line, while recommended to be held within the confines of the compressor casing may well turn out to require some user piping. There are some situations where the desire for keeping open space around the compressor for maintenance may require compromise on the part of the user. The balance of the connections on the axial are for lube oil and other auxiliary equipment not different from that found on other compressors. 

Purchase price of equipment turbine, compressor, auxiliary equipment, and heat recovery equipment, if desired. 

Cost estimates are presented below for pulse jet cleaned fabric filters. The eosts are expressed in fourth quarter 1998 dollars. The cost estimates assume a conventional design under typical operating eonditions and do not inelude auxiliary equipment... 

Condensate from contact units cannot be reused and may constitute a waste disposal problem. Surface condensers can be used to recover valuable condensate. Surface condensers must be equipped with more auxiliary equipment and generally require a greater degree of maintenance. 

Guided missile and space vehicle parts and auxiliary equipment, n.e.c. ... 

In addition to the formation of scale or corrosion of metal within boilers, auxiliary equipment is also susceptible to similar damage. Attempts to prevent scale formation within a boiler can lead to makeup line deposits if the treatment chemicals are improperly ehosen. Thus, the addition of normal phosphates to an unsoftened feed water ean eause a dangerous eondition by elogging the makeup line with preeipitated calcium phosphate. Deposits in the form of calcium or magnesium stearate deposits, otherwise known as "bathtub ring" can be readily seen, and are caused by the eombination of ealcium or magnesium with negative ions of soap stearates. 

Can several process steps be carried out in separate processing vessels rather than a single multipurpose vessel This reduces complexity and the number of raw materials, utilities, and auxiliary equipment connected to a specific vessel, thereby reducing the potential for hazardous interactions. 

Improvements in engine and turbine design, along with the use of auxiliary equipment such as catalytic converters, selective catalytic reduction (SCR) units and the use of steam and water injection into turbines, combine to reduce overall emission levels. 

---