NLWA report highlights concerns about possible use of MBT

The seven London boroughs which make up the NLWA – Barnet, Camden, Enfield, Hackney, Haringey, Islington and Waltham Forest – are currently developing a joint waste strategy (see letsrecycle.com story).

As part of their strategy, the NLWA is looking at new and emerging waste technologies including pyrolysis, MBT, Biological and Mechanical Treatment (BMT) and anaerobic digestion.

In a report to the Authority, a cabinet committee states that following the decision of the East London Waste Authority to go for MBT, it sees the process as the “only emerging technology that had so far proved bankable in London”. But the committee revealed concerns about the “limited market capacity for Refuse Derived Fuel”.

It went on to say: “Balanced against this were concerns about the limited market capacity for Refuse Derived Fuel produced by the process, and the fact that the calorific value of the waste meant that this could not be further treated in an Energy from Waste plant such as Edmonton, without further significant modification.”

Integrated
The discussion of new and emerging technologies by the NLWA comes after it acknowledged that the Edmonton incinerator or its replacement could be “insufficient to achieve sufficient waste diversion to achieve the Landfill Directive targets even if higher recycling rates were achieved and waste minimisation programmes were successful”.

Members of the cabinet committee believe that an integrated approach, using “several of the new technologies” will be needed. The main problem facing the NWLA is that the technologies they are looking at are unproven at the scale they would be needed in North London.

Comparing the difference between MBT and BMT, the meeting heard that while MBT produces fuel pellets for recovery or landfill, BMT produces a low-grade compost. The NWLA noted that while MBT has a greater land-take than BMT, it is less expensive.

• At a meeting last week members of the NLWA discussed whether to refurbish Edmonton's five boilers or replace them with two larger capacity boilers to bring the facility into line with the Waste Incineration Directive (see letsrecycle.com story). The recommendation by LondonWaste to refurbish the existing boilers was passed by the committee.