Usually, delignification processes are carried out within factory ovens at high temperature and pressure, using foul-smelling chemicals to dissolve the lignin. And after delignification, a further bleaching process is involved, also requiring high temperature and pressure. This invention provides an economical delignification method which completely or partially removes lignin by irrigating biomaterial agglomerated in a heap with chemicals. In this novel delignification method the irrigation solution that has run off to the bottom of the heap can be collected and transferred to a pool or storage unit to be recycled for future usage.
This technology of obtaining cellulose raw materials is achieved by exposing heaps of wood pieces on a basin to chemical irrigation solution in an open field. The solution will help dissolve the lignin leaving behind the cellulose, and it is collected at the bottom of the basin which it will be treated and recycled to be used again in the delignification process. Using this simple stacking system, it is possible to remove lignin and perform the bleaching process in one step without applying heat, pressure or malodorous chemicals.
This solution can be adopted in the pulp and paper industry. It is also widely applicable to industries that need a lot of cellulose materials, and it offers an economical solution to meet their needs. The used solution from delignification process can be recycled in the irrigation again after performing quality control and optimisation. This process will continue until the desired delignification rate is achieved. The method has low carbon emissions and can be used as an environmentally friendly alternative to the current state of art where strict regulations are in place.