Glenfiddich scotch whisky distillery upgrades to BIOdek
Scottish whisky distilleries are subject to some of the most demanding environmental regulations in the world, particularly regarding discharge of wastewater into the local water sources. The environmental and regulatory challenges are compounded by a very practical problems involved in maintaining the purity of local water sources which also happen to be the ultimate destination for the constant flow of high-strength wastewater generated during the production process.
One of the world’s leading distillers of premium quality Scotch whisky has responded to these multi-faceted challenges with an increasing focus on sustainable, chemical free wastewater treatment techniques and technologies.
In 2016, the company commissioned 2H Water Technologies to supply the process, civil, mechanical and control aspects of a biological Effluent Treatment Plant (ETP) based on BIOdek structured plastic media at a distillery located in Dufftown, Scotland. With over 20 stills, 45 warehouses plus an evaporator plant, onsite cooperage, coppersmith and bottling centres and a current production capacity of 10 million litres per year, the distillery is one of the company’s – and Scotland’ – largest whisky production facilities.
The BIOdek ETP, which went live in 2017, meets the customer’s requirement for a sustainable, chemical-free and efficient industrial wastewater treatment that removes biological and chemical oxygen demand from the liquid effluent to ensure wetland fauna and flora is not oxygen deprived – and flourishes. And because it’s built from structured, modular BIOdek media, the new ETP will expand, easily and cost-effectively, to meet changes further increases in throughput and other changes in regulatory or operational demand.
So effective is the BIOdek ETP that, following a routine test by an influential Scottish environmental protection agency, one of the inspectors involved declared the treated wastewater “good enough to drink”!
THE UPGRADE PROCESS
The upgrade process began in 2013, when a planned increase in production volumes at the Dufftown plant prompted the company to replace an onsite Effluent Treatment Plant (ETP) which was based on a three- stage ‘Davenport’ rectangular section trickling filter system and two mineral – rock – media filters. 2H Water Technologies responded with a comprehensive proposal for the process, civil, mechanical and control aspects of a trickling filter system built from BIOdek structured plastic media.
Over the next two years, the company carried at a detailed evaluation of other industry-leading effluent plant processes before concluding that an energy-efficient Biodek trickling system would provide the most effective effluent treatment.
Working in conjunction with the main contractor, DSI (Design Supply & Install Ltd), 2H Water Technologies presented an updated proposal in 2015. In the proposal, 2H drilled down to the details of the system, matching recommendations on the type of BIOdek media with detailed evaluations of the effluent and the flows which would be passed and handled by the trickling filter system. In addition, 2H provided details of the recycle system which would be required to keep the filter beds efficiently wetted.
The following year, 2H Water Technologies was commissioned to supply the process design, manufacture and install BIOdek trickling filters and three Equiflo rotary distributors as part of a collaborative project with DSI.
EFFECTIVE, CHEMICAL-FREE WASTEWATER TREATMENT
2H Water Technologies designed and built customised BIOdek modules for each of the three circular-section trickling filters which, together, provide comprehensive carbonaceous treatment and nitrification. In addition, the new trickling filters incorporate new settlement and pumping stages plus a variable speed Equiflo rotary distributor and control system.
The BIOdek Trickling Filter Solution:
Filter (Stage) 1 BOD and COD heavy duty removal
Dimensions: 13.6m diameter x 7.2m
Media: 1,046m3 BIOdek KFP627 crossflow & KVP623 vertical flow
Filter (Stage) 2 BOD and COD secondary removal
Dimensions: 13.6m diameter x 7.2m
Media: 1,046m3 BIOdek KFP619 crossflow
Filter (Stage 3) BOD and COD final polishing
Dimensions: 13.6m diameter x 7.2m
Media: 1,046m3 BIOdek KFP619 media
TOTAL MEDIA SURFACE AREA: 125m2/m3 and 150m2/m3
TOTAl MEDIA VOLUME: 3,138m3
MEDIA BED DEPTH: 7.2m
THE EQUIFLO ROTARY DISTRIBUTORS
Three stainless steel distributors with ‘open trough’ arms designed to handle 30litres/second with constant flow. The machines are complete with motorised speed control systems to provide the facility to periodically flush the media surface to help maintain an efficient working biomass.
Carbonaceous Trickling Filter 1
- The top two media layers are built from welded blocks of BIOdek KFP627 media with a 60-degree cross-flow structure that ensures optimal distribution of wastewater through to the vertical media layers beneath.
- The nine lower layers are constructed from BIOdek KVP623 media with ribbed vertical tubes which provides a greater surface area and high mechanical strength.
- The bottom layer is made from a very heavy duty BIOdek KFP627 media to spread the load and water flow evenly over the media support system
Carbonaceous Filters (2 and 3)
- These two filters are both filled with KFP619 crossflow modular media with a top layer suitable for walking on and a bottom layer made from a very heavy duty BIOdek KFP619 media to spread the load and water flow evenly over the media support system
A “NATURAL APPROACH TO EFFECTIVE WASTEWATER TREATMENT
After being treated in the new BIOdek trickling filters, the wastewater stream is channelled into a constructed wetland that take advantage of the vegetation, soil and processes unique to wetlands to remove trace element, notably residual copper that emerges from the production process.
POLYPROPYLENE – GREENER, RE-USUABLE AND RECYCLABLE MEDIA
2H manufactured the BIOdek modules in Polypropylne (PP) which is more energy efficient and produces less carbon dioxide, has less chemical burden to interfere with biomass seeding and has a more durable lifetime and when finished with can be easily recycled.
In manufacture of the modules the welding process means no gluing with solvents and, therefore, in service life no potential for hydrolysis destroying the adhesive holding the modules together.
ADAPTABLE, FLEXIBLE WASTEWATER TREATMENT
The new trickling filters are built from modular BIOdek media meet the customer’s requirement for a wastewater treatment which could be expanded, easily and cost-effectively, to accommodate future production increases. Because they’re built from modular BIOdek plastic media, the trickling filters can be adapted or upgraded easily and cost-effectively to meet changing production needs and, importantly, increasingly demanding consents – all with minimal disruption to treatment productivity.