20.2 Cultivation and Processing of Microalgae

317

The origin should be from waste or sustainable sources;

Produced using land sustainably thereby considering habitats and biodiversities;

Do not disrupt/impact food production;

High-efficient biofuel generators;

Negligible impact on air quality.

Biofuels are the most anticipated results of logical exploration. The petroleum

products are being depleted, and contamination is expanding internationally. Green

growth biofuels are one of the promising choices [5]. The fast-developing populace

of the world constantly builds the worldwide interest for fuel vitality, and the seri-

ous utilization of fossil overall prompts its consumption and will bring them near

the purpose of weariness because of impractical and non-sustainable nature [6, 7].

20.2

Cultivation and Processing of Microalgae

Many pathways for generating biofuels distribute certain general aspects irrespec-

tive of the biomass feedstock being used, as shown in Figure 20.2. The pathway for

algal biofuel production includes a sequence of processes from algae cultivation to

collection and harvest, and finally to fuel conversion. Certain crops are being used as

biofuel feedstock because of their capability to generate oil and carbohydrates which

can be converted into fuels using microorganism. Some of those crops are soybean,

jatropha, etc., which are harvested and their oils are separated for further process-

ing. Dedicated energy crops for biofuel production include poplar, switch grass, and

miscanthus; they can grow with low inputs of nutrients and have the ability to store

carbon in the soil. The lignocellulosic biomass is then converted biologically, chem-

ically, or thermochemically into liquid fuels. Algal biofuel systems exist similar to

the above-mentioned feedstock types.

Different pathways are available for cultivating and processing algae to fuels and

their products. The pathways are depicted in Table 20.1 [7]. These pathways illus-

trate the requirement of resources and impacts associated with each method. The

Growth

CO2

Microalgae

Water

Other

nutrients

Harvest

and

recovery

Chemical

processing

Finished

fuels

Figure 20.2

Biofuel production pathway.