Petrom uses Smar Profibus PA equipment

Petrom Petrochemical Industry located at Mogi das Cruzes, São Paulo, Brazil, is known as the biggest manufacturer of phthalic anhydride in Latin America and has been investing in automation to increase their production. To improve the control process and to increase the security of their factories, the company has invested in the acquisition of Profibus PA technology.

The automation included three Phthalic Anhydride reactors and one vacuum distillation tower for a total of 1200 I/O points, including existing and new. The project was implemented with Profibus and ASI technology. Petrom's technical engineers and the systems integrator, CBTA, handled the engineering. Smar engineer César Cassiolato provided additional support for the specification and configuration of the network Profibus PA. By utilizing the Profibus technology for their automation, a 40% cost reduction was realized in the installation alone in comparison to a 4-20 mA system. The main savings resulted from the reduction in wiring. In addition, the panels were decentralized and trays and conduit were simplified to facilitate the installation and further guarantee cost savings throughout the system.

According to Petrom, the major cost benefits were recognized in the installation time, physical space, staff training and start-up time. All of the savings were possible due to the technical staff participation in the configuration and installation of the system and equipment. As a result, they are now qualified to handle the prospective changes during subsequent stages of the project as the technology is implemented in different areas of the Phthalic Anhydride plant.

Two CPUs were used to control the plant. One is used to control two Phthalic Anhydride reactors and the second one is used for the remaining reactor and the vacuum distillation tower. The tree type topology was used for the Profibus PA network, with nine links and couplers DP/PA. This allowed for up to 21 components in each segment, with more than 150 altogether. Most of the field equipment is from Smar and all of the equipment is connected to the PA network through the JM1 coupling box from Smar.

In the Anhydride factory alone, Petrom invested approximately US$520K in the acquisition of equipment, supervision software and field assembly. This represents 15% of the total project investment, which is divided into six stages. At the conclusion of the expansion (scheduled for the beginning of 2005), the company will have an annual production capacity of almost 80 thousand tons of Phthalic Anhydride, 90 thousand tons of plasticizer and 3,600 tons of Fumaric Acid.

According to Marco Cusma of Petrom, during the implementation of the new technology, the factory did not shut down. "While overcoming this challenge, new executions became even simpler. In addition, the training of the involved personnel became easier because the Profibus concept is assimilated without difficulties", he explains.

"In assuming the engineering of the project from the beginning and knowing the configuration and installation details, we can now modify the conceived structure to improve the process operation, whenever it is necessary. Petrom has a technological alliance with Smar in the instrumentation and control area due to the technical support offered during the specification phase, the application and in after sales. This support, along with the quality of the equipment, provided us a high operational availability of the factories ", concludes Cusma.

Phthalic Anhydride Applications

Phthalic Anhydride is used mainly in the production of plasticizers, unsaturated polyester resins and alkyd resins. Due to it being both economical and having ideal characteristics for resins processing, it is the saturated acid most often used in the manufacture of plastic products. It is also used to produce anthraquinone and its derivatives, phthalocyanine, phenolphtalein, fluorescina, in addition to others.