A bioreactor is a container which is used to hold organisms for the purpose of harnessing their natural biochemical processes. A simple and well known example of a bioreactor is a fermentation tank for beer, in which certain microorganisms are encouraged to thrive, causing the contents of the tank to ferment and creating a usable end product. There are a number of types of bioreactors, and they are used for a variety of purposes, from processing solid waste to manufacturing pharmaceuticals.
In a batch bioreactor, everything is added at once to a controlled and sealed environment, and the biochemical reactions are allowed to run their course before the reactor is opened so that the contents can be extracted and utilized, disposed of, or further processes. Others operate on a continuous flow method, in which materials constantly flow through the bioreactor. Waste treatment plants, for example, utilize continuous flow to process solid waste.
A number of criteria must be satisfied when a bioreactor is built. In order for the device to be effective, the conditions need to be tightly controlled, which means that there must be ways to moderate temperature, light levels, moisture, oxygen, and other components of the environment. It is also important to isolate the contents from contaminants so that the bioreactor will work properly, and so that adverse reactions do not occur. In beer, for example, the introduction of the wrong microorganisms can cause the beer to sour.
Conversion of organic waste such as compost or solid waste is a common application for bioreactors. When built properly, the reactor can greatly speed the breakdown process, which contributes to overall efficiency. Bioreactors are also used to promote growth, as for example in the production of tissue cultures, or the cultivation of specific fungi utilized in pharmaceuticals. In some cases, it may be necessary to devise a custom device to meet the specific needs of a particular application, in which case the skills of a biochemist are typically required.
Researchers are constantly devising new uses for bioreactor technology. For example, these devices could potentially be used to produce energy, or to grow tissue and bone grafts. Chemical production can rely heavily on bioreactors, depending on the compounds being manufactured, as can large-scale processing of compost and yard waste for municipalities. Many experiments have also been conducted with bioreactors in challenging environments such as space to learn more about biochemical processes and to generate useful scientific information.