»»Cathay Industrial Biotech

Bioprocesses and Their Advantages
Bioprocesses have a number of advantages compared to traditional chemical processes:

• Feedstock Flexibility.

A majority of industrial bioprocesses use relatively inexpensive, non-petroleum-based feedstock such as corn and other harvest crops, sucrose and vegetable oils. Recent research has sought to extend feedstock sources to include forest residues, mill residues, agricultural residues, municipal solid wastes and grasses. With world oil prices having increased from an average of US$36 per barrel in 2004 to over US$70 per barrel recently, non-petroleum feedstock has generally become increasingly cost competitive with the petroleum-based raw materials that chemical processes use. Growing global political uncertainty, rising demand in emerging markets, limited fossil-based energy supply, increasing cost of drilling activities and underinvestment in infrastructure could lead to rising and increasingly volatile oil and natural gas prices, further increasing the attractiveness of bioprocesses.

• Advantages in Operating Requirement.

Bioprocesses generally work under conditions that are compatible with life, such as at temperatures under 100°F, near atmospheric pressure and in water-based solutions. In contrast, chemical processes generally require higher temperatures and pressures and operate in solvents. As a result, bioprocesses require a lower amount of energy to drive reactions. In addition, bioprocesses generally require fewer steps than chemical processes to produce the same, or functionally similar, compound, which can lead to lower setup and operating costs. For example, traditional chemical processes produce diacids through multiple chemical reaction steps, while bioprocesses produce diacids in a single fermentation step followed by purification. Cost savings from these advantages may offset the constant pressure imposed by the commodity pricing environment for most industrial chemicals.

• Ability to Produce New Molecules.

Bioprocesses can also produce molecules that cannot be produced economically on a meaningful scale, or at all, through chemical processes. For example, among diacids with chain lengths ranging from 10 to 18 carbons, only a few (primarily diacid with a chain length of 12 carbons) can currently be produced economically through chemical processes, while a majority can be economically produced through bioprocesses. Polymers made from these longer-chain diacids have improved qualities such as greater flexibility and reduced moisture absorption, and can create new value-added downstream applications.

• Environmental Friendliness.

The fewer steps and milder conditions associated with bioprocesses can significantly reduce energy consumption, hazardous waste generation and disposal costs. By using renewable, biomass-based feedstock, bioprocesses can also decrease dependence on fossil fuels and reduce carbon dioxide emission, a significant advantage over the negative impact on the environment associated with the traditional chemical and fuel industries. In addition, certain products made through bioprocesses have similar performance characteristics to functionally equivalent products made through chemical processes, but offer greater biodegradability.

• Production Scalability.

Bioprocessing and fermentation facilities are modular and can be readily expanded to accommodate growing volume by adding additional fermentation tanks or pieces of equipment to existing systems. Most bioprocesses operate at temperatures below 100 o F, near atmospheric pressures and in water-based solutions with near neutral pHs. Therefore, the installed fermentation tanks can be built using common stainless steel at reasonable thickness. In contrast, chemical facilities often require precious metals due to the solvents used and extreme operating conditions required. Bioprocesses also use similar fermentation and purification equipment for many products, allowing easy switching between products without significant down time. Furthermore, bioprocess plants can be built near any rural area where bio-feedstocks are readily available, which increases flexibility in choosing plant locations and reduces land costs. This contrasts with petrochemical plants that typically need to be close to a crude oil refinery or natural gas pipeline. Moreover, new petrochemical plants are subject to environmental restrictions in many countries.