Cerritos, Mexico: a record cement plant
Cerritos, in the state of San Luis Potosi, is a plant with elevated technological innovation, that was inaugurated last July 29th and is distinguished for the record time, 27 months, in which it was built: the worksite was opened in February 2002 and the start up of the kiln took place in May 2004.
The cement plant is located at a height of 1,250 m above sea level, in a broad green valley that contrasts with the semi-desert typology of the surrounding areas. It is entirely controlled by a control room positioned in the Engineering Building, built in the colonial style with attractive arched elements - recalling the constructional characteristics of the local Mexican tradition - and containing the management offices, laboratory, operations control and cafeteria.
Among the feathers in the cap of the new factory, born of the experience matured with the realization of the Tepetzingo cement plant seven years ago, are the 2 Horomills 3800 of 100 t/h each, whose electricity consumption is the lowest currently obtainable, the precalcination towers, built with the same innovative architectural technique as those of Tepetzingo, a mixed structure in reinforced concrete and steel with the supporting tubular columns with rectangular section in whose internal spaces are located the stairs, elevator, chimney, the flue for the hot gases and the electrical cables.
Moreover, the pedestrian tunnels with the power supply and signal cables and the piping for water and compressed air, the two circular prehomo halls for the raw materials equipped with stacker and reclaimer, with a total capacity equal to 40,000 tons. Furthermore, with the respect for the environment that characterizes the Group policies, the limestone quarry is designed on the underground well-tunnel system and boasts of a reforestation plan for 220 hectares of territory.
In order to better connect the cement plant with the outside, an exclusive expressway interchange has been realized that enables the trucks to avoid the inhabited center, and an internal railroad feeder line has been built from scratch, for which 2.5 km of railway track have been laid, so as to be able to make use of trains for the supply of petcoke and, in the future, the shipping of the cement. The cement plant will be fed by a train composed of 60 railcars whose length, 1 km, has required particular tactics for the handling.
Within a radius of about 500 km from the plant, the largest and most populated Mexican cities are found: Mexico City, Queretaro, Monterrey, Guadalajara, Tampico. The small state of San Luis Potosì is characterized, in fact, by its central position with respect to the entire country and by its housing density, since the population is concentrated above all in its capital which bears the same name.
The 'municipality' of Cerritos, with the hamlet denominated Montaña, in the territory of which the factory has been installed, is located about 60 km from San Luis Potosì, northwards, and 40 km to the west of the "Carretera federal 57", one of the most important arterial roads of Mexico that joins the capital to Monterrey and the United States.
All the raw materials necessary for the production are found in the immediate vicinity. The limestone reserve is approximately 600 m from the facilities; the clay reserve is about 3 km away, in addition to other deposits, such as the quarries of gypsum and pozzolana, that are found at a distance of a few tens of km.
Among the other systems that were purpose-built is the high voltage power line, 27 km long and with a voltage equal to 115 kV, sufficient for all the current installations and also for future expansions, that presently leads to a power transformer substation with a capacity equal to 30 MW. Furthermore, two wells have been drilled - with a depth greater than 250 m - for the water requirements of the plant and also for the local community of Montaña, which previously lacked waterworks and was supplied occasionally by the local government with tank trucks. Cerritos was designed so as to cancel out the consumption of water for the conditioning of the process gases while, for the indispensable water consumption dedicated to the cooling of the machines, a system was installed that consists of a tank of 1000 m3 and four evaporator towers; another tank of 250 m3 is provided for fire-fighting use.
The global design, expandable further if necessary, consists of two production lines of which one is realized and the other is under construction for a total investment of 240 million dollars.
- 1.250.000 t/year is the cement production capacity installed before the doubling
- 3000 t/day is the clinker production capacity of the kiln
- 580.000 m 2 is the surface area involved by the facilities
- 26.500 m 2 is the surface area for the covered technical areas
- 2.800 m 2 is the surface area for the buildings adapted as offices
- 68.000 m 3 is the total volume of reinforced concrete used
- 5.430 tons is the weight of steel reinforcement rods used
- 3.500 tons is the total weight of the steel structures