ADVANCED VACUUM DRYING SYSTEM (AVDS)
Conditions ILW nuclear waste inside final,disposable container | Innovation Award Winner
Highly Commended by the Nuclear Decommissioning Authority
The Advanced Vacuum Drying System (AVDS) is an innovative, proven conditioning solution for intermediate level nuclear waste (ILW) sludge. AVDS applies heat, vacuum and refrigeration to remove moisture content from sludge.
Wastes are dried to ensure their passivity for long term storage. The waste is conditioned in its original and final, disposable container. Moisture content is removed down to a level of less than 1% wt/wt (waste dependant).
The award-winning AVDS facilitates cost efficient ‘in-box drying’ for long term, above ground storage in self-shielded Disposable Waste Containers, offering an alternative to the traditional concrete encapsulation of ILW.
AVDS - OVERVIEW
Large scale, turnkey, closely controlled vacuum dryer for conditioning of intermediate level waste in its final, transportable, disposable container for long-term, above ground storage
Winner of Magnox Sites i4 Awards, Innovation Category 2014
Highly commended by Nuclear Decommissioning Authority for innovative solution
AVDS - HOW IT WORKS
A Vacuum Conditioning Unit (VCU) controls specially constructed heater panels, which encase the containers. The system incorporates high level control automation, powering up to six drying stations simultaneously, safeguarding efficiency and minimising operator intervention.
A high efficiency 2-stage condenser system removes virtually all water vapour from the process gas leaving only non-condensable gas in the exhaust line. The aqueous effluent recovered from the waste is collected in a condensate collection tank and then periodically transferred to an IBC before final disposal.
The control system accurately determines the point at which the waste has reached its required level of dryness to eliminate under-drying or wasteful over-drying.
The AVDS has an integrated Hydrogen Management System which prevents any hydrogen that may be generated during drying from forming a flammable atmosphere.
AVDS - FEATURES
Large scale, closely controlled vacuum drying
Final moisture content down to less than 1% wt/wt
Automatic endpoint determination
Up to six stations simultaneously controlled
Waste is conditioned inside the final disposable container (Type VI cuboidal and Mosaik)
High level control automation
Hydrogen management system
Minimal operator intervention
Duty/standby condenser system for uninterrupted drying
Installation, commissioning, operational qualification
UK designed, manufactured & supported
Proven technology - actively drying at nuclear decommissioning sites
AVDS - FROM PROTOTYPE TO ACTIVE CONDITIONING
The video below is about the prototype AVDS, for Magnox Berkley Site. It was commissioned by Magnox and produced by Cineon Productions in 2013:
The video below, commissioned by Magnox in 2017, is about the AVDS installed at Dungeness A Site:
What Magnox said to MechaTech Systems about the prototype build:
"..just wanted to...pass on my thanks for all the effort you and your team have put into this project… I am extremely grateful for your perseverance, tenacity and hard work.."
"In a few months we have gone from having no solution at all to having a state-of-the-art rad waste drying system which is going to become very popular in the near future. Truly fantastic..."
Today, AVDS is actively conditioning waste at UK nuclear decommissioning sites. MechaTech Systems have now delivered five AVDS systems (last updated August 2020).
MechaTech Systems conduct small scale trials of simulant waste using our in-house vacuum drying trials rigs for other nuclear decommissioning clients, both in the UK and overseas.