In paper production processes, during stages of pulping and bleaching, chemicals such as the choloride components, chlorolignin, undigested carbohydrate products, and even lipophil components are released and formed into sludge. Removing the remaining lignin from this product will reduce the volume of chemicals required for bleaching resulting in a reduction of harmful chemicals in the sludge by products at the paper production factories. Chlorine is a component that combines with the lignin of pulps resulting in a major contamination source of the environment.
To help prevent the contamination, bio-treatment can be performed on the sludge using microorganisms. This is especially true with the white rot fungi that have degradative enzymes. The sludge can be degraded completely by the use of these microorganisms during aerobic and anaerobic digestion and its quality will therefore be improved. The use of biological methods not only decreases side effects but also results in the reduction of water and energy consumption. With the use of lignin degradative fungi, in the process known as bio-pulping, we are able to treat chips before mechanical pulping. This method, depending on wood resources, will lead to the decrease of the consumption of electrical energy by 30-43 % while also improving the quality of paper. Clearly, Xylanase reduces the amount of chemicals, like chlorine, required for bleaching up to 10 %. White rot fungi contains wood component degradative enzymes that are capable of degrading a great variety of organic materials. By isolating these fungi and similar microorganisms along with the application of some genetic manipulation, the commercial production of them for the biological treatment of plant waste containing polymers, like lignin, is made possible. We can also use these microorganisms for the treatment of wastes in plant related industries such as the dye, olive oil, and textile industries.