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Control Equipment Issues

Weekend shutdown maintenance at WP L has shown some unusual deposits on the ESP plates and wires, but the deposits are soft and easily removed.18 [Pg.275]

United Power Association experienced good fabric filter operation when burning up to 10 percent TDF. However, when the facility tested TDF levels up to 65 percent, operation of the fabric filter was of primary concern. The ash from the rubber was significantly more difficult to cleanoff the bags than the coal ash. The resultant ash build up on the bags caused an increased pressure drop across the system from 3 to 6 . Personnel operated the cleaning cycle continuously, and operated both reverse air fans for the duration of the test, which improved the situation.17 [Pg.275]

The Northern States Power facility experienced significant operational problems with their electrolyzed pebble bed scrubber during tests burning from 7 to 9 percent TDF (mixed with woodwaste) in a retrofitted fluidized combustion bed boiler. The electrostatic voltage dropped to near zero on several occasions on others, the collection efficiency declined continually. Several reasons for this are suggested. First, the ash during the test was more cohesive [Pg.275]

Note Tick mark indicates average emission rate bar shows +/-2 standard deviation range in data. Bars are truncated at zero. [Pg.276]


Also, the electronic control-valve device s level of immunity to, and emission of, electromagnetic interference (EMI) can be an issue in the chemical-valve environment. EMI requirements for the control-valve devices are presently mandatory in the European Community but voluntary in the United States, Japan, and the rest of the world. International Electrotechnical Commission (lEC) SOI, Parts I through 4, Electromagnetic Compatibihty for Industrial Process Measurement and Control Equipment, defines tests and requirements for control-device immunity. Immunity and emission standards are addressed in CENELEC (European Committee for Electrotechnical Standardization) EN 50 081-1 1992, EN 50 081-2 1993, EN 50 082-1 1992, and prEN 50 082-2 1994. [Pg.786]

In addition, a facility that shredded whole tires into TDF was visited. At each site, information was collected on the processes using tires, modifications necessary to accommodate tire use, control equipment in use, effect of tire use on emissions, control equipment effectiveness, cost of process and control equipment changes, changes in personnel or resource needs, and benefits of tire use. Problems using tires, and tire supply issues, such as source, quality, and reliability, were also discussed. [Pg.147]

The layout of the change house provides for an orderly flow and control of personnel having a security control point, locker room with shower facilities, lunch room, clothing/equipment issue, and storage area. In addition, medical facilities required to support a chemical operation include an ambulance. [Pg.287]

In most practical combustion installations there are two separate parts of the equipment system (1) the burner itself and (2) all of the peripheral equipment necessary to control the burner operation efficiently and safely. The control equipment includes fuel and oxidant pressure and flow controls automatic shutoff controls flame supervision equipment furnace purge equipment and other related devices. The safety issues of the burner are significantly different in character as compared with the safety issues of the control equipment. In many ways, these two safety issues are diametrically opposed. Within the burner, fire is a desired condition, whereas within the control system and surrounding environment, fire is to be avoided entirely. [Pg.266]

Other issues relate to the physieal loeation of the sawyer and not being able to gauge on either side of the saw. With small eucalypts, there is the need for a lot of face-cutting. With a one-man resaw the sawyer is located next to the saw and relies on remote controlled equipment to feed the saw. This operation is impreeise and slow. The sawyer cannot orientate a fliteh with the same degree of precision as with a two-man resaw consequently sueh saws are best fed with accurately sized material. With a two-man resaw the sawyer loeated in line and on the in-feed side of the saw is well placed to earry out minor eorreetions to the flitch orientation prior to sawing and where necessary to tum/prepare material for resizing. [Pg.236]

Site-specific issues impacting the selection of the control equipment, must be quantified. These include availability of utilities, pace constraints, disposal options, and cost of residue generated by emissions control. [Pg.663]

Vatavuk Air Pollution Control Cost Index (VAPCCI 1994 = 100) FOB vendor quotes for U.S. conditions for nine types of air pollution control equipment. Pubhshed in each issue of Chemical Engineering. [Pg.1305]

Systematic safety integrity issues including avoidance of failures, control of systematic faults, system behavior on fault detection, and proven equipment issue. [Pg.435]

The situation proves to be completely different when it comes to computer installations. Experts are by no means agreed on which faults are to be considered likely and how faults can be avoided or remedied. The software - a completely new element in computer-controlled equipment -also raised new problems in the safety issue whereby only the checkability of the system and the ease of modification are to be mentioned here. [Pg.247]

High voltage electrical equipment can only be worked on in safety if either the part of the apparatus or equipment to be worked on is permanently and adequately earthed, so that it is electrically dead at all times, or the apparatus or equipment is first made safe by earthing, tested for verification, and then released for work by the issue of a E permit. Before any work is carried out on remotely or automatically controlled equipment such as circuit breakers and isolators, the automatic or remote controlled features must first be rendered inoperative. [Pg.85]

Most aroma chemicals are relatively high boiling (80—160°C at 0.4 kPa = 3 mm Hg) Hquids and therefore are subject to purification by vacuum distillation. Because small amounts of decomposition may lead to unacceptable odor contamination, thermal stabiUty of products and by-products is an issue. Important advances have been made in distillation techniques and equipment to allow routine production of 5000 kg or larger batches of various products. In order to make optimal use of equipment and to standardize conditions for distillations and reactions, computer control has been instituted. This is particulady well suited to the multipurpose batch operations encountered in most aroma chemical plants. In some instances, on-line analytical capabihty is being developed to work in conjunction with computer controls. [Pg.85]


See other pages where Control Equipment Issues is mentioned: [Pg.275]    [Pg.275]    [Pg.26]    [Pg.127]    [Pg.352]    [Pg.125]    [Pg.143]    [Pg.144]    [Pg.216]    [Pg.814]    [Pg.268]    [Pg.130]    [Pg.17]    [Pg.71]    [Pg.70]    [Pg.274]    [Pg.54]    [Pg.9]    [Pg.226]    [Pg.589]    [Pg.19]    [Pg.15]    [Pg.88]    [Pg.642]    [Pg.115]    [Pg.44]    [Pg.243]    [Pg.128]    [Pg.296]    [Pg.193]    [Pg.216]    [Pg.77]    [Pg.347]    [Pg.246]    [Pg.517]    [Pg.329]    [Pg.447]    [Pg.324]   


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Control equipment

Controlled Equipment

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