Civil Engineering
T
he
Civil
Engineering
Department
criteria
groundwater depletion and another one on the establishment of
specifications for the acquisition of
criteria to determine structural integrity and estimate the useful
developed
new
seismic
one on the main aspects of soil fracturing and subsidence due to
equipment for electric power transmission
life of pipelines subject to major deformations.
substations which allow definition of levels of
seismic rating to be complied by electric power
The Structures Safety Information System (SISE) was developed
substations in order to improve their reliability
at the behest of the Subdepartment of Structures Safety of the
in the event of seismic activity. In addition, a
Federal Electricity Commission (CFE) and was implemented
new procedure for describing the foundations
to optimize processes and facilitate analysis of the information
for a new definition of design spectra were
required to prepare reliable reports on the safety of civil
developed. Finally, a geographical information
engineering structures within electric power generating plants.
system application was developed for handling
SISE´s technical features allow the user to calculate the
information and the seismic rating of electrical
variables that control system behavior: deformations, rotations,
equipment.
displacements, collapses, etc.; to register anomalies in particular
works and follow up on the recommended actions; and to identify
At Km. 1001+000 on the Ciudad Pemex-
anomalies in structures based on the results of inspections.
Guadalajara Right of Way (DDV) of the 36”
OD Gas Pipeline a crack appeared in the soil
CFE´s Department of Transmission Line and Substations
caused by regional draining due to extraction
Projects of the Subdirectorate of Financed Investment Projects,
of groundwater. In this project, contracted by
requested the development of a new version of the Pre-Filling-
Pemex Gas Basic Petrochemicals, we determined
out and Bidder Modules of the Program for the Streamlining of
the strain produced by soil cracking in the
Tenders (ProSiL).
5 pipelines in the DDV. The pipelines were
The Pre-Filling-out Module now enables personnel in
instrumented with strain gauges and a wireless
CFE offices located at different points in the Mexican Republic
data acquisition system was incorporated
to work together, via Intranet, on the preparation and control of
to monitor deformations periodically. Two
versions of pre-filled-out documents corresponding to a tender.
complementary projects were also carried out:
The Bidder Module now contains commands that facilitate
information input by allowing it to be imported from Excel files.
It also includes commands to locate information that has not
been entered or identify failure to comply with critical dates,
which are common reasons for disqualification in tenders.
Progress was made in developing a methodology for seismic risk
studies on pipeline systems in operation, based on developing
damage scenarios and their effects on the surrounding
environment and supported by a database of the elements
involved, among them: topography, geology, seismic danger and
pipeline system maps, all of which is managed with a geographical
information system.
Electrical Research Institute
20
Materials and Chemical Processes
A
s part of the project Mexico in the implementation of the Kyoto Protocol,
work continued on the analysis of Clean Development Mechanisms
(MDL) and on calculations of emissions of Greenhouse Gases (GEI) with
different emission factors. Upon conclusion of this project a manual or general
guide will be obtained containing the results and possible forms of implementation
of MDLs in GEI emission sources (fixed or mobile), whether already installed or to
be installed in the future. The purpose of this project is for the methodologies to
support CFE in identifying projects that could qualify as MDLs in order to obtain
resources through Carbon Emission Credit Trade.
Technologies for treatment of emissions resulting from the burning of heavy
fuels were reviewed. This will allow IIE to define the basic research and future
development for control of sulfur oxide (SOx) emissions produced by the use
of fossil fuels with high sulfur content in the generation of electric power. In
parallel, the development of thermally stable and regenerative catalytic adsorbent
mesoporous materials, with emphasis on the use of cerium and copper oxides,
was undertaken. A catalogue of commercial desulfurization technologies currently
being developed was compiled, with the aim of having technical support for
decision-making regarding control of sulfur compounds emissions in the country’s
thermoelectric plants and refineries.
Information was gathered and analyzed in reference to aspects of maintenance
and operation of the steam generators at the Tula and Minatitlán refineries, at the
Cangrejera petrochemical complex and at the Cactus gas processing complex. On
the basis of this information a diagnosis of the current status of the equipment
and a forecast of its useful life were obtained.
At the request of the General Superintendent’s Office for
Pipelines, Tlaxcala Sector, of Pemex Gas and Basic Petrochemicals
(PGPB), the status of the anticorrosive covering of the 12” LPG
on the Venta de Carpio-San Juan Ixhuatepec Right of Way was
assessed. The result of this work determined the coverage of
the cathodic protection system and possible interference from
a preventive maintenance program for the
induction caused by structures alien to the pipeline.
compression and regulation station.
Personnel from the Maintenance Department (GM)
of the Subdirectorate of PGPB Pipelines took the training and
Through a subcontract with the Electric
certification course in Direct Current Voltage Gradient (DCVG)
Equipment Department, a feasibility study
technique Level I. The object of the course was to certify
for the development of a model of humidity
personnel in the technique so as to enable Pemex to have better
in power transformers began. This is being
preventive maintenance planning for its pipeline installations.
developed within the framework of technological
Ultrasonic inspection of pipelines at critical points of the
development projects financed by national
Venta de Carpio sector was concluded. This made it possible to
private industry, specifically the company Prolec
prepare a report on the current status of the welds and a graphic
GE, and from the National Council on Science
identification of discontinuities found in order to establish
and Technology (CONACYT).
2004
Annual Report
21
Thermal Processes
T
he study group of the Department of Thermal Processes (GPT) which specializes in
thermoelectric power plants (CT), carried out various projects this year. At the request of
the CFE’s José Aceves Pozos CT, this Department carried out the engineering design and
technical specifications for pipes and accessories for the new steam pipeline for fuel atomization,
as well as new designs for flame stabilizers and atomizers that will replace the current mechanical
atomization of fuel in oil burners in units 1 and 2. In collaboration with the Department of Control
and Instrumentation, the GPT drew up the technical specifications and basic engineering for
automation and control of burners and pilots in these units, and incorporated cutting-edge digital
technology.
Two stages of the evaluation of the thermodynamic cycle including the circulation water
system of the Lerma CT were carried out to determine the derating caused by the main equipment
of units 1, 3 and 4. As a result, corrective actions were identified, aimed at reducing the decrease in
power and improving the units’ availability and efficiency. Computer models are now available to
analyze the steam cycle in the Lerma Power Station units.
This Department provided technical-analytical support for the
management, implementation and development of Pemex’s
Electric Power Administration Center by defining, evaluating
and selecting operative, technical, regulatory and administrative
initiatives to enable this State-owned enterprise to obtain –as the
main benefits– lower operating costs (steam and electric power)
and to cover its power and steam needs.
As Technical Secretariat of the Planning and Energy Policy Group
(GPPE) of the Ministry of Energy (Sener), the GPT carried
out activities to assess fuel and electricity supply alternatives
in different supply, demand and energy-price scenarios. With
the results obtained, Sener is preparing recommendations for
medium and long-term energy policy to guarantee a timely
supply of fuel and electricity to all the country’s sectors at lowest
cost and with lower risk. It should be stressed that the planning
process was developed for the long term, covering up to the year 2025.
The GPT provided technical-analytic support for a comprehensive evaluation of
cogeneration systems in Pemex and its subsidiary agencies and companies, and considering
transmission limitations, to quantify the electric power that could be used in other Pemex
centers, based on current power generation installations at the Cangrejera, Cactus, Tula and
Minatitlán centers. A methodology was also developed to determine, in a uniform manner, in all
Pemex agencies, electric power and steam costs. Finally, plant technical features were defined for
major cogeneration projects, which will increase the efficiency of this State-owned enterprise’s
electric power and steam generation processes. Leading-edge technology was proposed for these
plants which, in addition to reducing energy consumption, is environmentally friendly, such as
gasification integrated with combined cycles that would burn oil residuals and combined cycles
that burn natural gas.
Electrical Research Institute
22
Turbomachinery
T
he area of redesign and rehabilitation of turbomachinery components of this Department, applied –for the
first time in Mexico– technology for on-site repair of steam turbine housings. The procedure, developed for
correcting deformations of the housing, was applied in a 75 MW turbine at the Presidente Juárez Plant in
Rosarito, B.C.; here, the deformation distorted the necessary clearances between moving and stationary parts, which
caused loss of efficiency and severe friction between housing and rotor. A significant deformation of the housing was
eliminated and its original geometry was restored, as well as its design efficiency. Performing this type of work obviates
the need to acquire a new housing or send it to a specialized workshop for repair.
This Department had another achievement which represents a return to the field of hydroelectric generation:
optimization of the turbines impeller at the José María Morelos (Villita) hydroelectric plant, which completed an
important stage in the work by establishing a methodology that serves as theoretical support for the re-powering
and substitution of the national hydroelectric park. Based on these results, an agreement was reached with CFE’s
Coordination Office for Hydroelectric Generation to begin the work of formulating plans and defining procedures
for the manufacture of new impellers for the above-mentioned plant.
Work continued within the area of turbomachinery diagnosis and maintenance on the description of the turbines
and auxiliary equipment of CFE’s thermoelectric generation units. To that end, various units were analyzed on line, a
diagnosis was made of the status of the unit prior to the maintenance period and recommendations were issued to
prepare work for recovery of the loss of power and efficiency. Various units were also inspected with an open machine,
in order to pinpoint the necessary repairs to recover the major part of those losses.
Other activities of the area included the installation of the first combined-cycle SCORT system for online
operation at the Presidente Juárez plant in Rosarito, B.C. This makes it possible for the operators to know at
all times the parts of the cycle that are operating outside the design conditions, as well as their contribution to
economic losses, providing support for the control and optimization of the plant’s thermal regime.
Finally, two steam turbine rotors were
inspected and their useful life was
assessed so as to predict possible
failures. To that end, a borosonic
inspection of both rotors was carried
out, as well as an inspection of their
critical components by means of
various non-destructive techniques.
The results of the inspections were
used
together
with
specialized
computer codes to determine the
current status of the rotors from the
viewpoint of thermal fatigue and hightemperature operation. This is the
most extensive work performed thus
far to determine the remaining life
of 300 MW steam turbines, some of
which are already nearing the end of
their useful design life.
2004
Annual Report
23