Cement, Energy and Environment

Solution The bad condition of the old ESP did not allow Hascon to reutilize the existing structure, both for technical and economical reasons. The adopted solution was to remove the old ESP and its connection ducts. The steel and concrete stack was in good · condition and was made from a suitable material for withstanding humidity and high temperatures (about 270.C). Therefore, the decision was to keep and revamp it. Thanks to an inlet of fresh air, the temperature was reduced to 220 · c and was controlled by a modular control system of ''false-air''. This means that a continuous operational temperature can be maintained and therefore it is possible to use fiberglass bags without a heat exchanger, as the customer required. The dew point value, based on customer process data and environmental conditions, should be 112·c . far from the operative temperature of 22o·c. This dew point value forced Hascon to completely insulate the dedusting filter, including connection ducts and fan, to provide hopper heating tracing. Thanks to advanced technological devices, the company was able to achieve a bag filter dedusting system that is able to comply with the stack concentration required by the customer and by territorial authorities. Scope of supply This included: self-cleaning pulse-jet bag filters, type AJ-S- 05-M-12x16-6,5-3135 subdivided in independent compartments (five compartments on one line), main peculiarities are low pressure drop and limited compressed air consumption; execution in Corten A:5 rnm thick, properly stiffened. The filters will work with a bag cleaning system in online mode, but it will permit total exclusion of one compartment at a time for maintenance during operation. For this matter, each compartment is equipped with a dust air inlet and a clean air outlet, completed with exclusion electropneumatic valves (inlet horizontal butterfly valve and outlet poppet valves). Moreover, a manual exclusion slide gate valve is installed on the dust discharge outlet of the hopper. • Inlet/outlet ducts integrated in the filter body: welded Corten A5 mm thick. Sheet execution completed of inlet/outlet flanges with flexible expansion joints and internal by pass, complete with electropneumatic double poppet valve (cylinder, EV, two limit switches) and pressurizing system. • Fumes cooling with fresh air system including on/off butterfly damper with electropneumatic drive (cylinder, EV, N.2 limit switch), modulating damper complete with actuator and two IP55 temperature sensors (PT 100) with temperature transmitter (4-:-20mA output signal), integrated in the sensor head for fumes cooling system control. • One high performance centrifugal fan, single inlet, allocated downstream of the dust collector for gas suction directly into the exhaust stack. Conclusion Two significant examples are given of successful interventions for dedusting problems minimum cost possible. solving with Hascon Engineering can design customized plants optimizing the project in order to obtain the most economical and best technical solution finalized to match the emission values required by the up-to-date environmental norms. Courtesy: World Cement, February 2010, Pp 85-89 Environmental Improvement RAMESH DENIES NOD TO PROJECT IN ECO-SENSITIVE ZONES The National Board for Wildlife, headed by Environment Minister Mr. Jairam Ramesh, rejected some big project including a port in Gujarat, signalling that the ministry would not clear projects in ecologically sensitive zones. The standing committee of the board, in its meeting held recently, turned down a proposal for setting up a port at Poshitra in Jamnagar District of Gujarat, as the site was close to the Marine National Park in the Gulf of Kutch, rich in marine biodiversity and ecologically fragile. The committee noted that a report of the MS Swaminathan Committee had recommended that no port be developed in or around ecologically fragile zones. It also rejected a proposal made by Ambuja Cement that had sought to draw water from Majthal Wildlife Sanctuary in Himachal Pradesh , for the expansion of its cement plant. Courtesy: TERI (The Energy Resources Institute) Newswire, 1-15 Apri/2010, Pp15-16. 36