Nouvelles des membres de l’IIF : Star Refrigeration endigue une fuite d’ammoniac en un temps record (en anglais)

L'entreprise britannique d'ingénierie du froid a récemment conduit une opération de maintenance dans une installation frigorifique d'ASDA utilisant l'ammoniac comme frigorigène.

The IIR corporate member Star Refrigeration was founded in 1971 and has grown to become the largest independent refrigeration and heating, ventilation and air conditioning (HVAC) contractor in the United Kingdom (UK). It works with various industries from different sectors including temperature controlled storage, food and drink processing, chemical, and HVAC among others. The list of the different sectors covered by Star refrigeration is available following this link.


Star Refrigeration provides maintenance services through its Starcare programme. Thanks to being placed in a multitude of locations throughout the UK, the Operations Groups of Star Refrigeration are well placed to offer a fast response time in case of failure in any plant, as well as 24-hour technical support for over 300 businesses nationwide.


For instance, Star Refrigeration recently had to intervene in an ASDA distribution center after an ammonia leak was detected. Palletised goods are broken down at this site, located in Rochdale, UK, before being delivered to individual stores. The temperature needs to be controlled and maintained throughout the operation. The usual service provided by Star Refrigeration in this plant consists of 24/7 cover of the refrigerant plant, including remote monitoring and planned preventive maintenance (PPM) visits.


When an ammonia leak occurred at the Rochdale site at 9 PM, ASDA and Star Refrigeration worked together to assess the situation and get the plant up and running again as soon as possible.


Via the monitoring Hub at Star’s headquarters in Glasgow, standby engineers at the Manchester branch were notified of a "low stage drum high level" and went to the site to address the situation. The low stage surge drum was full of refrigerant and had carried over to the compressors, and an ammonia leak was detected on one of the low temperature compressors. This compressor had to be isolated from the ammonia system.

 

 

First of all, the concentration of ammonia in the plant room had to be lowered to allow safe entry. Star Refrigeration's engineers activated local ventilation fans and deployed additional extra fans to ensure there were no ammonia levels above 25 ppm. Then, when the room was safe to enter, a plan was put in place to transfer liquid between the surge drums and fit a replacement valve. There were three Star Refrigeration engineers on site in addition to the customer’s. They all worked as a team to get the plant back up and running. The cold store plant was out of action for 11 hours in total.


Colin Taylor, SHE Manager at the ASDA site said, “What really impressed us about Star was the way our emergency was handled. The plant tripped out at 9 pm, and with two senior engineers and a manager attending and working through the night, the cold store was working again by at 8.30 am the next day.” A senior maintenance engineer from Star Refrigeration underlined the importance of working in partnership with the customer.