BACKGROUND

THE SOLUTION

Séché Environnement, created by Mr Joël SÉCHÉ in 1985 is one of France's leading players in the recovery and treatment of both indus-trial and household waste. The Group currently employs around 1,900 people located both in France (20 sites) as well as abroad, still under competent leadership of Mr SÉCHÉ. Since the company inception its subsidiary Séché Eco-Industries has operated a waste handling facility in Changé, near the city of Laval, approx. 300 km west-southwest of Paris. From the non-recyclable waste fraction the site produces SRF (known in France as Combusti-bles Solides de Récupération or CSR) which is sold to large energy users such as the cement industry.

Séché Eco-Industries was already engaging in the concept of the now widespread term of “circular economy” since the end of the 1980s when it started to produce process heat from the SRF waste and ex-porting this to the adjacently located farmers owned co-operative CoDeMa (Coopérative de Déshydratation Mayennaise) for their stock feed drying operation (now known as Coopérative DESHYOUEST).

In 2014 a new company Laval Energie Nouvelle (LEN), created by Coriance, a French heating network operator and Séché Eco-Industries, was entrusted by the local authority to operate the district heating network of the Ville de Laval for 20 years.

The brief was to produce the maximum amount of 12 bar saturated steam while reusing existing site infrastructure such as the flue gas treatment system. For the light fluffy SRF/CSR LLT selected a 15 MWth circulating fluidised bed (CFB) integrated with a 3 pass water tube boiler. Oil fuel burners are included for both start-up and load purpos-es to comply with the 2 s/850°C during turn down operation.

LLT was awarded the order for the steam raising plant which is part of the € 27.5 million in investment for the new SRF fired energy facility made by SECHE ENVIRONNEMENT with just under 25 % of CAPEX supported by ADEME subsidies (heat fund and waste fund).

Creating Energy Solutions For The Future [PROJECT 520 048]

SÉCHÉ ECO-INDUSTRIES CHANGÉ, LAVAL [F]

15 MWth SRF Fired CFB Boiler for DH & Process Heat

Part of this agreement was to both expand the network to reach more heat users as well as reduce the carbon foot print of the network’s mainly natural gas fired heat sources. Hereto it was decided to inte-grate the waste fired heat generation in operation at the Changé site into the heating network. It was realized quickly by the engineers that the existing rotating kiln combustion in combination with the fire tube boiler was not going to be up to the task. A specification was drawn up and the search commenced to find a reliable provider with a proven thermal energy system solution to handle the difficult waste fuel.

KEY DATES

PROJECT OBJECTIVE

SCOPE OF WORK

TECHNOLOGY

PROCESS DATA

ENVIRONMENTAL IMPACT

SÉCHÉ ECO-INDUSTRIES, LAVAL [F] 15 MWth SRF Fired CFB Boiler for DH & Process Heat

To produce heat for the local district heating network and stock feed dry-ing operation using solid recovered fuel (SRF) produced on site.

The plant is part of the Séché Changé Energy Hub which is designed to generate 70 GWh heat per annum, using Solid Recovered Fuel and pro-vide 6,400 homes of hot water for heating as well as process heat for the adjacent feed stock drying operation.

Circulating Fluidised Bed combustion technology with propriety loop seal based on LLT design c/w multilevel secondary air injection. Steam is gen-erated in a 3 pass vertical watertube boiler designed and manufactured by Leroux & Lotz Technologies.

Fuel surge bin (day silo) Circulation Bubbling Fluidised Bed (CFB) Combustion System Saturated Steam Watertube Boiler with Economisers Diesel/LFO Fired Burners

Parameter Unit Value

Fuel Source - SRF

Fuel Flowrate kg/h 2,700

LCV (Moisture Content) MJ/kg (w/w%) 15-23 (1-15)

Steam Flow/ Pressure/ Temp. tph/bara/°C 23/ 12/ 192

Thermal Capacity MWth 15

Emissions NOx/CO mg/Nm3 (11 % O2) <200 / <30

Schematic Overview of heat system

Circulating Fluid Bed Cyclone being lifted in place with the first boiler pass with drum and CFB system

awaiting erection

Solid Recovered Fuel known as CSR in France

10 rue des Usines 44185 Nantes, France, Tel +33 (0) 2 40 95 96 97

10 rue Irene Joliot Curie 38320 Eybens, France, Tel +33 (0) 476 14 77 70

Email : contact@lerouxlotz.com

LEROUX & LOTZ TECHNOLOGIES

H E A T & P O W E R Creating Energy Solutions for the Future

APRIL 2016 OCTOBER 2017