HALOTECH ™ WETLAND SYSTEMS FOR PRIMARY WASTEWATER TREATMENT
Craig Fannin and Paul Danes
AMEC Earth & Environmental (UK) Ltd
(free)
The treatment of waste management effluents is seen as an energy intensive process when a high quality effluent is required. In contrast, constructed wetlands are generally recognised as an energy efficient and sustainable system but limited as regards to primary treatment of high strength effluents and hence to date their use has been restricted to tertiary applications. This paper presents a summary of the development and performance potential of a modified constructed wetland system, the ‘HaloTech’ wetland which is capable of acting as a primary treatment system for the landfill leachate components: ammoniacal-N, BOD and COD as well as heavy metals.
The system design and associated treatment biomass can be adapted for both aerobic and anaerobic processes and therefore a complementary system can be built for the treatment of organic substances, nitrification, denitrification and heavy metal precipitation. This type of system is designed as a low energy (dosing pumps) requiring minimal active management and hence is the most sustainable treatment option currently available for industrial and waste management effluents.
Extensive laboratory and on-site pilot-scale trials over a four year period have culminated in the commissioning of one full-scale treatment bed during 2007/8 and the ongoing construction of a second system.
KEY WORDS Constructed Wetland, Ammoniacal-N, BOD Primary Treatment
