Xylose hydrolysate decolorization and filtration device and decolorization and filtration method using same

A method of using a xylose hydrolysate decolorization and filtration device wherein the xylose hydrolysate decolorization and filtration device comprises:

• (i) a decolorization tank;
• wherein the decolorization tank is configured to receive a pre-decolorized liquid and mix the pre-decolorized liquid with new carbon added in the decolorization tank to form a new carbon liquid,
• (ii) a filtering unit;
• wherein the filtering unit comprises at least three filtering machines connected in parallel, wherein
• the at least three filtering machines respectively perform a reciprocating cycle among three working states of standby, to-be-passed-through, and to-be-cleaned;
• and
• at least one of the filtering machines is a standby filtering machine in a standby state, at least one of the filtering machines is a to-be-passed-through filtering machine in a to-be-passed-through state, and at least one of the filtering machines is a to-be-cleaned filtering machine in a to-be-cleaned state;
• wherein the standby filtering machine is configured to filter the new carbon liquid to form a decolorized liquid,
• wherein the to-be-passed-through filtering machine is
• (a) configured to contain carbon that passed through the decolorization tank;
• wherein the to-be-cleaned filtering machine is
• (a) configured to contain waste carbon that passed through the to-be-passed-through filtering machine;
• (b) configured to be cleaned to become the standby filtering machine;
• and
• (c) configured to filter an incoming xylose hydrolysate to obtain a waste carbon liquid;
• wherein the to-be-cleaned filtering machine, the to-be-passed-through filtering machine, and the standby filtering machine are respectively provided with a hydrolysate pipe, a new carbon liquid pipe, a plate and frame liquid pipe, a pre-decolorized liquid pipe, a decolorized liquid pipe, and a waste carbon liquid pipe;
• wherein the hydrolysate pipe is provided with a hydrolysate valve, the new carbon liquid pipe is provided with a new carbon liquid valve, the plate and frame liquid pipe is provided with a plate and frame liquid valve, the pre-decolorized liquid pipe is provided with a pre-decolorized liquid valve, the decolorized liquid pipe is provided with a decolorized liquid valve, and the waste carbon liquid pipe is provided with a waste carbon liquid valve;
• (iii) a filter press;
• wherein the filter press is configured to perform pressure filtration on the waste carbon liquid to form a plate and frame liquid;
• wherein the to-be-passed-through filtering machine is configured to filter the plate and frame liquid to form the pre-decolorized liquid;
• and
• (iv) a storage tank;
• wherein the storage tank is configured to store the decolorized liquid
• wherein the method comprises the following steps:
• step I, opening the hydrolysate valve to enable a xylose hydrolysate to enter the to-be-cleaned filtering machine from a hydrolysate pipe and then enter the waste carbon liquid pipe while carrying the waste carbon in the to-be-cleaned filtering machine through the waste carbon liquid valve, such that the hydrolysate is decolorized and filtered to become a waste carbon liquid with a light transmittance increased from 0 to 7%-10%, wherein the to-be-cleaned filtering machine is cleaned to change the state of the to-be-cleaned filtering machine from to be cleaned to standby;
• step II, transporting the waste carbon liquid in the waste carbon liquid pipe into the filter press for pressure filtration, wherein a clear liquid produced by the pressure filtration is a plate and frame liquid;
• step III, opening the plate and frame liquid valve to transport the plate and frame liquid in the plate and frame liquid pipe into the to-be-passed-through filtering machine, and enable the plate and frame liquid to pass through a carbon filter cake in the to-be-passed-through filtering machine and then enter the pre-decolorized liquid pipe through the pre-decolorized liquid valve, such that the plate and frame liquid is decolorized and filtered to become a pre-decolorized liquid with a light transmittance of the pre-decolorized liquid increased from 7%-10% to 30%-35%, and the state of the to-be-passed-through filtering machine is changed from to be passed through to be cleaned;
• step IV, transporting the pre-decolorized liquid in the pre-decolorized liquid pipe into the decolorization tank, adding new carbon to perform stirring for some time, and then enabling the mixture to enter the new carbon liquid pipe, wherein the pre-decolorized liquid and the added new carbon are mixed into a new carbon liquid;
• step V, opening the new carbon liquid valve to enable the new carbon liquid to enter the standby filtering machine from the new carbon liquid pipe to produce, through filtering, a clear liquid with light transmittance being ≥65%, transporting the filtered clear liquid into the decolorized liquid pipe through the decolorized liquid valve, wherein a filtered new carbon liquid becomes a decolorized liquid, and a state of the standby filtering machine is changed from standby to be passed through;
• and
• step VI, collecting the decolorized liquid in the decolorized liquid pipe into a storage tank to complete the hydrolysate decolorization and filtration process.