Plant processes for deinking paper and magazinesDeinking is the process of removing the ink fromrecyclable sources such as newspapers and turing it into pulp which is used toproduce clean paper which can be used to fulfil other needs. There are manymethods of deinking such as flotation deinking, bleaching and washing whicheach have their own benefits and drawbacks. Flotation deinking utiliseschemicals in order to fully remove all the ink present on the paper by bubblingthrough air the sample in the presence of a foaming agent and the ink attachesitself to the bubbles and is removed from the paper fibres. However the airbubbles through can remove some of the clean paper fibres resulting in wastebeing produced and reduces the yield of the process reducing its effectiveness.This process is mainly used to deink newspapers and magazines and as this isthe main paper source for the processing plant this process would be ideal forthe plant as it suits its feedstock and gives a high quality product.Another deinking process that may be suitable isbleaching which removes ink from paper by using chemicals such as hydrogenperoxide to bleach the colorants of the ink on the paper and thus removing thecolour of ink. Bleaching is primarily used to produce very bright paper as itis added to the recovered pulp to brighten the paper.
This means that it willmainly produce high quality bright paper suitable for graphic papers and sowould not be applicable for the plant as their goal is to produce paper thatcan be used in an office environment.Another process used for deinking papers is washingwhich is primarily used to produce high quality hygiene papers. Used to removethe unwanted inks and other impurities which can be found on the pulp bywashing it on a thin wire screen. It involves adding dilute pulp to the washingwater which contains a dispersal to remove all the small contaminates leftbehind from the previous process. A drawback of this process is that itproduces a high volume of waste and so is not very economically viable unlessthe plant can convert the waste into .
This will make the overall process more efficientby using its waste products as a source for energy. This could be achieved by forexample incinerating the waste products for energy which can be used to powerthe process of washing or flotation deinking and will therefore reduce costs. Washingshouldn’t be used as a main process as it primarily creates hygiene paper butthe plant wants to produce high quality office paper and it therefore doesn’t suitthe plant’s needs.