Cement, Energy and Environment

ENVIRONMENT PROTECTION & RESOURCE MANAGEMENT Pollution Control SOLVING DEDUSTING PROBLEMS IN CEMENT PLANTS WITH MINIMUM COST Hascon Engineering S.p.A., Italy. Introduction Hascon Engineering S.P.A., Italy, is one of the leading companies for dedusting systems, as well as gaseous fluid and dust pneumatic conveying, focussed on safeguarding the environment. The company has 35 years of experience in producing and assembling different kinds of plants all over the world, which has enabled it to gain strong technological know-how in solving industrial process-related pollution problems. In the cement plant sector, the company has realized dedusting plants for rotary cement kilns, cement mills and material handling. This article presents two case studies detaining successful installations. Case A Special bag filter technical data: AJ-D-(14x 13 x 3) three compartments. The customer is a partner of a significant Italian cement group based in southern Italy. The aim was to reduce ESP stack emissions, which, at the time, exceeded security rules by 20 times the legal value (200mg/Nm 3 ) . The solution also needed to consider cost efficiency parameters. The answer was not to replace the whole filter but to revamp the existing outdated Flow rate Temperature min/max Bag material Table-1 Bag filter technical data 180000m% 1OO'C/200' C Fibreglass with PTFE microporose membrane 3,276 m 2 Total filtering surface Filtering velocity 0.91 m/1 min ---~'----- Total filtering surface with one compartment off Filtering velocity with one compartment off Bag cages Compressed air consumption DP filter Bag diameter Total length Number of bags 2184 m 2 1.37 m/1min Aisi 304L -20 vertical wires 300 Nm% at 5 - 7 bar 1007150mm. c.d.a. circa 160mm 6000 mm 1092 Number of clearing electrovalves 78 (2 in.dia.) Application Supply Kiln capacity Flow rate Table-2 Design data Revamping ESP into bag filter installed on rotary cement kiln 3.276 m 2 bag filter with three filtering sections by pneumatic valves 32tph 180 000 m 3 /h at 140' C Figure 1. Self-cleaning pulse-jet filter (upper part). 33