Missed Opportunities—Strategy and Procedures for Testing Alarm and Shutdown Devices

1982 ◽  
Vol 104 (2) ◽  
pp. 186-190
Author(s):  
P. S. Koelle
Keyword(s):  
Systematic Approach ◽  
Plant Performance ◽  
Process Equipment ◽  
Missed Opportunities ◽  
Safety Devices ◽  
Plant Personnel ◽  
Rotating Equipment ◽  
Efficiency And Reliability ◽  
Training Of Personnel

Loop testing of safety devices during operation improves plant performance, reduces downtime of process-dependent rotating equipment, and enhances training of personnel. Designers, manufacturers, staff engineers, and plant personnel are always concerned with improving the efficiency and reliability of process equipment. An unscheduled shutdown caused by breakdowns or accidents involving machinery may result in millions of dollars in unrecoverable losses, because the capacity of rotating equipment has increased to a point where temporary replacements to enable the plants to continue their production are hard, or even impossible, to find. The paper will discuss how accidents may be prevented and outline a systematic approach to checking alarm and trip circuits.

Plant Performance Monitoring: Improving Surveillance of Rotating Equipment on a Gas Processing Plant

2009 ◽  
Author(s):  
Jean-Gregoire Boero-Rollo ◽  
Bernard Galtie ◽  
Pierre-henry Tincelin ◽  
Nicolas Kessler ◽  
Xavier Lacoux
Keyword(s):  
Performance Monitoring ◽  
Plant Performance ◽  
Processing Plant ◽  
Gas Processing ◽  
Rotating Equipment

scholarly journals Systematic Modeling of Municipal Wastewater Activated Sludge Process and Treatment Plant Capacity Analysis Using GPS-X

2020 ◽  
Vol 12 (19) ◽  
pp. 8182
Author(s):  
Nuhu Dalhat Mu’azu ◽  
Omar Alagha ◽  
Ismail Anil
Keyword(s):  
Activated Sludge ◽  
Suspended Solids ◽  
Systematic Approach ◽  
Municipal Wastewater ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Plant Performance ◽  
Capacity Analysis ◽  
Activated Sludge Process ◽  
Effluent Quality

Mathematical modeling has become an indispensable tool for sustainable wastewater management, especially for the simulation of complex biochemical processes involved in the activated sludge process (ASP), which requires a substantial amount of data related to wastewater and sludge characteristics as well as process kinetics and stoichiometry. In this study, a systematic approach for calibration of the activated sludge model one (ASM1) model for a real municipal wastewater ASP was undertaken in GPS-X. The developed model was successfully validated while meeting the assumption of the model’s constant stoichiometry and kinetic coefficients for any plant influent compositions. The influences of vital ASP parameters on the treatment plant performance and capacity analysis for meeting local discharge limits were also investigated. Lower influent chemical oxygen demand in mgO2/L (COD) could inhibit effective nitrification and denitrification, while beyond 250 mgO2/L, there is a tendency for effluent quality to breach the regulatory limit. The plant performance can be satisfactory for handling even higher influent volumes up to 60,000 m3/d and organic loading when Total Suspended Solids/Volatile Suspended Solids (VSS/TSS) and particulate COD (XCOD)/VSS are maintained above 0.7 and 1, respectively. The wasted activated sludge (WAS) has more impact on the effluent quality compared to recycle activated sludge (RAS) with significant performance improvement when the WAS was increased from 3000 to 9000 m3/d. Hydraulic retention time (HRT) > 6 h and solids retention time (SRT) < 7 days resulted in better plant performance with the SRT having greater impact compared with HRT. The plant performance could be sustained for a quite appreciable range of COD/5-day Biochemical Oxygen Demand (BOD5 in mgO2/L) ratio, Mixed Liquor Suspended Solid (MLSS) of up to 6000 mg/L, and when BOD5/total nitrogen (TN) and COD/TN are comparatively at higher values. This work demonstrated a systematic approach for estimation of the wastewater treatment plant (WWTP) ASP parameters and the high modeling capabilities of ASM1 in GPS-X when respirometry tests data are lacking.

scholarly journals Efficiency and reliability of membrane processes in a water reclamation plant

2015 ◽  
Vol 5 (2) ◽  
pp. 166-176 ◽  
Author(s):  
Mohamed F. Hamoda ◽  
Meshari AL-Harbi ◽  
Hasan AL-Ajmi
Keyword(s):  
Suspended Solids ◽  
Reclaimed Water ◽  
Oxygen Demand ◽  
Plant Performance ◽  
Process Efficiency ◽  
Water Reclamation ◽  
Total Coliforms ◽  
Normal Probability ◽  
Normal Probability Distribution ◽  
Efficiency And Reliability

Performance of a water reclamation plant using ultrafiltration (UF) and reverse osmosis (RO) treating 280,000 m3/d of wastewater was evaluated over 1 year. Statistical analyses were performed on flow rate, temperature, pH, total suspended solids (TSS), total dissolved solids (TDS), biochemical oxygen demand (BOD5) and total coliforms. Variations in flow rates coincided with those in temperature, both being seasonal, but plant performance was not highly influenced by such variations. The RO system recovered 85% of water flow. Data on process variables conform to a normal probability distribution and reveal the high process efficiency and reliability of UF and RO systems. Plant efficiencies were &gt;99% for TSS, TDS, BOD5 and total coliforms. Efficiencies were the highest for TSS and total coliforms in the UF system, while they were the highest for TDS and BOD5 in the RO system. Cumulative frequency distribution analyses indicate that RO plays an important role in maintaining a stable plant performance and high quality reclaimed water. The UF system proved essential for complimenting successful performance of the RO system. Reclaimed water satisfies, at 99% frequency, the quality standards for potable water concerning TSS, TDS, BOD5 and total coliforms even though membranes have been operating continuously for 6 consecutive years.

From Commissioning to First Year Operation of a Modern Coal Fired 242 MW Plant Facility

2009 ◽  
Author(s):  
Kuda R. Mutama ◽  
Norm Duperron ◽  
John Seeliger
Keyword(s):  
Power Plant ◽  
Steam Turbine ◽  
Catalytic Reduction ◽  
Heat Rate ◽  
Daily Basis ◽  
Lessons Learned ◽  
Plant Performance ◽  
First Year ◽  
Reheat Steam ◽  
Plant Personnel

In this paper lessons learned during the period from commissioning the TS Power Plant to first year of commercial operations are discussed. It is hoped that the experience at TS Power Plant will be valuable to other new plants during the post-commissioning phase. In June 2008 the TS Power Plant commenced commercial operations. The plant is designed for a gross power output of 242 MW. Combustion takes place in a sub-critical B&W radiant boiler, which uses PRB coal for fuel to generate 1,491,000 lb/hr superheated steam at a design pressure and temperature of 2650 psi and 1055 °F respectively. The steam is used to drive a Toshiba reheat steam turbine generator set. To date the plant performance is better than expected. Actual HP turbine throttle pressures at desired load are less than design with a lower heat rate than expected. The plant has state of the art technology and follows strict emission removal standards in accordance with its air permit for the reduction of CO, NOx, SO2, mercury and particulate matter. Plant personnel addressed problems ranging from mechanical, instrumentation and control, to freezing weather issues during the first year of operations. On several occasions the plant experienced forced outages and personnel had to troubleshoot in order to identify the root cause of the problems. The critical problems developed with the DCS, coal handling system, fans and air dampers, boiler combustion systems, steam turbine auxiliaries, selective catalytic reduction system, spray dry absorber, and water treatment. A significant number of the problems were carried over from facility commissioning and new ones developed during normal operations. Plant personnel had to work through these problems on a daily basis. The operating staff had gained significant experience during the plant commissioning phase by participating in loop shooting and equipment commissioning. It is also important to note that operations staff completed a General Physics training program designed specifically around the TS Power plant systems during construction. The plant was running relatively smoothly with an average availability of 99.84% for the last three months of 2008.

Plant Performance Monitoring: Improving Surveillance of Rotating Equipment on a Gas Processing Plant

2009 ◽  
Author(s):  
Jean-Gregoire Boero-Rollo ◽  
Bernard Galtie ◽  
Pierre-henry Tincelin ◽  
Nicolas Kessler ◽  
Xavier Lacoux
Keyword(s):  
Performance Monitoring ◽  
Plant Performance ◽  
Processing Plant ◽  
Gas Processing ◽  
Rotating Equipment

“Shhhh! Alex Has Something To Say”: AAC-SGD Use in the Classroom Setting

2010 ◽  
Vol 19 (4) ◽  
pp. 108-114 ◽  
Author(s):  
Lisa M. Mellman ◽  
Laura S. DeThorne ◽  
Julie A. Hengst
Keyword(s):  
Social Interaction ◽  
Social Interactions ◽  
Augmentative And Alternative Communication ◽  
Classroom Community ◽  
Classroom Observations ◽  
Classroom Teachers ◽  
Classroom Setting ◽  
Alternative Communication ◽  
Structured Interviews ◽  
Missed Opportunities

Abstract The present qualitative study was designed to examine augmentative and alternative communication (AAC) practices, particularly surrounding speech-generating devices (SGDs), in the classroom setting. We focused on three key child participants, their classroom teachers, and associated speech-language pathologists across three different schools. In addition to semi-structured interviews of all participants, six classroom observations per child were completed. Data were coded according to both pre-established and emergent themes. Four broad themes emerged: message-focused AAC use, social interactions within the classroom community, barriers to successful AAC-SGD use, and missed opportunities. Findings revealed a lack of SGD use in the classroom for two children as well as limited social interaction across all cases. We conclude by highlighting the pervasive sense of missed opportunities across these classroom observations and yet, at the same time, the striking resiliency of communicative effort in these cases.

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