FUEL FLEXIBILITY & PLANT DESIGN OPTIONS
In close cooperation with leading boiler suppliers, INMIS offers its customers flexible solutions designed to achieve optimal operational and financial results by configuring each plant according to project-specific parameters and customer priorities.
Essentially, the different plant design options offered by INMIS Energy S.A. reflect a trade-off between operating costs (via fuel flexibility) and initial investment costs.
When lowering the upfront costs is prioritized, the basic, stripped down plant versions offered by INMIS will be designed to operate with a single fuel or group of fuels with similar and technically non-challenging characteristics,
On the other end, if maximizing fuel flexibility is the primary objective, INMIS is able to provide and guarantee a plant designed to operate with most types of agricultural residual biomass fuels that are available in Greece.
TECHNICAL CHALLENGES & CAPEX/OPEX TRADE-OFF
In a Turboden ORC based power plant, biomass purchasing costs typically represent anything between 50 to 80% of the total operating costs. When a plant is therefore designed to operate with a wide range of fuels, plant operators will be able to effectively lower operating costs by selecting among diversified fuel sources and by adapting their fuel sourcing strategy according to fuel seasonality and prices.
Fuel flexibility comes however at the expense of higher initial investment. Agricultural materials in particular, pose special design requirements both on the combustion side and on the treatment of flue gas.
| BIOMASS CHARACTERISTICS | |||
| COMBUSTION | LHV | Ash melting | Density |
| Design implications | Oversized equipment | Lower combustion temperature | Feeding system & combustion chamber |
| FLUE GAS TREATMENT | Chemical composition | ||
| Design implications | Additional filtering equipment |
On the combustion side the main fuel characteristics of concern are the calorific value (Lower Heating Value | LHV), the ash melting behavior (ash softening point) and the density of the material. Fuels with low calorific value will require oversizing several components of the thermal oil boiler, while fuels with low ash softening points will require lowering the combustion temperature inside the combustion chamber in order to avoid deposits, slagging, fouling and corrosion. Lightweight materials on the other hand will pose problems both in the hydraulic feeding system and also in the combustion process itself due to their ignition behavior.
On the flue gas treatment side, dealing with agricultural fuels of aggressive composition requires the use of additional filtering equipment and effectively increases the initial investment costs.
MORE INFORMATION
To view more on INMIS' boiler partners click here 
For more information on INMIS' products and services for biomass plants here or contact our business development department through here