Bostik enhances overfill protection

Redditch, UK - A multi-point alarm overfill protection system, installed on latex- and bitumen-based storage tanks is playing a crucial safety role at Bostik’s manufacturing plant at Saltney, near Chester, UK. The site, formerly owned by Laybond Products, manufactures flooring adhesives, roofing systems and general building products.

Bitumen is a key ingredient in many of the products produced on site, but its properties dictate that it is delivered and stored at elevated temperatures. Bostik’s investment in the overfill safety systems - from Redditch-based level measurement company Hycontrol - is intended to improve the safety of its employees, tanker drivers and the environment.

The Bostik safety systems are based around Hycontrol’s RF admittance level switches and ATEX vibrating probes. Together with their associated alarm panels, these act as overfill protection safety level switches to prevent hazardous overfilling during product discharge from delivery tankers. In the event of impending overfill problems, audio and visual alarms warn drivers and operators of any potential dangers, allowing ample time to shut down the fill process.

The RF admittance switches can be used on liquids, solids, slurries, pastes, granules, powders and pellets in high temperature, high pressure and corrosive environments. They are designed to totally ignore product build up on the sensing probe, making them suitable for products such as hot bitumen. The design utilises a protective insulation electrode between the conventional main electrode and the grounding sleeve, which enables the built-in electronics to distinguish between coatings and actual product.

There are four RF switches installed on the vessels in the Bitumen Cutback Tank Farm connected through to a four point alarm panel - Cutback bitumen is bitumen whose viscosity has been reduced by the addition of a suitable volatile dilutant. A further four RF switches and their associated twin alarm panels are fitted to a bank of four bitumen tanks which feed the manufacturing processes.

A single RF switch and single point alarm panel protects a latex storage tank. Again the capability of the RF switch to ignore product build up is important for this difficult-to-measure and sticky product. Finally, a solvented bitumen tank is fitted with an ATEX intrinsically safe HYCTF high temperature vibrating probe and special hazardous area single point alarm panel with an integral ATEX Namur barrier.