Bioenergy Engineering

Introduction

Biomass is material derived from plant and

animal sources.

Products of Forestry, Agriculture, Urban and

Industrial Waste Disposables are sources of

biomass that may be converted into biofuels

Objectives of Bio-energy Program:

• To make bio-energy a major energy

source & elevate its present status as

the ‘poor man’s oil’ into a modern

energy source, use advanced

techniques.

• Produce biomass renewably and

convert it efficiently into electricity,

gaseous, liquid and processed solid

fuels.

What categories of biomass

are sources?

• From agriculture, residues and energy

crops.

• From forests, trees.

• From Urban and rural waste and

treatment and disposal, solid, liquid and

gas fuels.

TREES OF INDIA

Energy resource

BIOMASS UTILIZATION

BIOMASS UTILIZATION

• Biomass production needs in addition to

plant or seed, the inputs of allocation of

land, soil with nutrients, water and

labour. Photosynthesis yields food,

feed, fodder and materials and energy

may be derived from byproduct of these

uses. Conversion of biomass can yield

energy as heat and transport fuel.

BIOMASS CONVERSION

METHODS

• Combustion

• Pyrolysis

• Gasification

• Fermentation

• Transesterification

• Physical, Chemical processing

Agro-residues and agro-industry residues-2

• Biomass residues and by products are

available in abundance at the agro processing

centres (rice husk, bagasse, molasses,

coconut shell, groundnut shell, maize cobs,

potato waste, coffee waste, whey), farms

(rice straw, cotton sticks, jute sticks).

briquetting or pelleting

• The process is called

biomass briquetting or pelleting.

• Compressed biomass briquettes are usually cylindrical in shape with a diameter between 30 to 90 mm and length varying between 100 to 400mm.

• Briquetting consists of applying pressure to a mass of particles with or without a binder and converting it into compact aggregate. Ram type and screw type machinery are used for the manufacture of briquettes.

Biochemical conversion

• Residual sugar from molasses can be

converted to ethanol/ butanol through

fermentation.

• Lipase enzymes catalyze release of

fatty acids from triglyceride (oil/fat)

which then react with methanol to yield

biodiesel.

• Anaerobic digestion is a microbial

process that yields methane rich gas.

Liquid biofuels

Liquid biofuels, usually in the form of alcohol, can

be produced from the plant components oil, sugar

and starch, and ligno-cellulose containing plants

can be converted to solid fuel, methanol, synthetic

gas or ethanol.

The most important liquid biofuels produced from

biomass are ethanol, methanol and fatty acid

methyl ester (biodiesel).

Ethanol is of particular importance, since it can

readily be used as a fuel for spark ignition

engines.

It can be produced from a wide range of

agricultural products: sacchariferous

materials such as sugar cane, sugar beet and

sweet sorghum; starchy materials including

cereal grains, cassava and potatoes.

Production of vegetable oil as a substitute for

diesel fuel is a relatively simple process. It

involves extracting the oil from the oilseed,

filtering, degumming and reducing its

viscosity through trans-esterification by using

ethanol or methanol. Tree borne non-edible oil

like jatropha may be utilized with methanol and

catalyst.

Cogeneration

The Biomass Power Programme of India has

reached the take off stage, after dedicated and

sustained efforts over the last decade. The total

potential is about 19,500 MW, including 3,500 MW of

exportable surplus power from bagasse-based co-

generation in sugar mills, and 16,000 MW of grid

quality power from other biomass resources.

BIOMASS INTEGRATED GASIFIER /GAS TURBINE (BIG/ GT) TECHNOLOGY

• HIGH THERMODYNAMIC CYCLE EFFICIENCY GAS TURBINES TECHNOLOGY IS MADE

AVAILABLE NOW AT REASONABLE COSTS LOW UNIT CAPITAL COST AT MODEST SCALES

FEASIBLE IT IS EXPECTED THAT THIS TECHNOLOGY WILL

BE COMMERCIALLY SUCCESSFUL IN THE NEXT TEN YEARS.

Biomass energy is not necessarily the ‘poor man’s

fuel’, its role is rapidly changing for a combination of

environmental, energy, climatic, social and economic

reasons. It is increasingly becoming the fuel of the

environmentally-conscious, rich society. The use of

biomass energy has many pros and cons. One of the

major barriers confronting renewable energy is that

the conventional fuels do not take into account the

external costs of energy, such as environmental

costs.