New Innospec plant has materials handling sorted

Ellesmere Port, UK - Speciality chemicals company Innospec  has recently started up the first new-build plant on its Ellesmere Port site since 1996. The facility, which manufactures products for personal care applications, features a special materials handling system for charging the process reactor.

The main ingredient of the product is delivered to site in big bags (FIBC’s). For each batch, a number are charged into the process reactor together with a catalyst from 25kg bags added manually through the discharger’s access doors. Charging the reactor takes an hour - which was the time specified from the outset.

As the big bags arrive in ISO containers that have travelled over land and sea, their normally free-flowing, flake-like contents can be somewhat compacted, especially in those bags at the bottom of the pile. To overcome the difficulties that such compaction can cause, a Spiroflow big bag discharger is fitted with bag massagers that operate on both the sides and the base of the bags.

Innospec's Ellesmere Port plant was designed to replicate a US plant, which makes a similar product for the US market. The US-based plant incorporates an aero-mechanical conveyor to transfer the ingredients from the big bag discharger to the reactor.  However, Innospec's design team instead opted for a flexible screw conveyor to better reduce the overall cost of the new plant - given its tight budget.

The chemical maker's main concern about going for the lower-cost option flexible screw conveyor, rather than the aero-mechanical ssytem, was degradation of the main ingredient - which has to retain its flake format for optimum performance in the reactor vessel. However,  these were concerns were overcome following trial at Spiroflow's test centre and comments corporate projects manager Bill Swift:  “We are well satisfied with our Spiroflow big bag discharger and although we chose the lower-cost flexible screw conveyor it has proven to be very efficient”.

Innospec's new plant is designated as a hazardous zone; rated to gas zone 2 and dust zone 22. To save cost, the main control panel was mounted remotely on the outside of the building with a zone-rated local control panel adjacent to the big bag discharger. The entire discharger was also earth-bonded and the flexible screw conveyor equipped with an antistatic conveying tube.

According to Swift, simplicity was the best option when it came to connecting the flexible screw conveyor to the reactor. Given that the reactor reaches temperatures of over 300 degrees C, rather than use a complicated double butterfly arrangement with a purged spool piece between, the flexible connection from the conveyor to the reactor is simply disconnected and reconnected as required so that the aperture can be closed by a pressure tight hatch once the reactor has been charged.