Methods and systems for processing plants and converting cellulosic residue to crude bio-oils

Abstract

A continuous flow wood processing technology for extracting lignin from woody plant material and converting the delignified cellulosic residue to crude bio-oils is provided. Wood is chipped before processing starts and fed into a lignin extractor. The lignin extractor uses ethanol at high temperatures to dissolve the lignin with counter current material contactors. The ethanol containing dissolved lignin is removed from the lignin extractor, the dissolved lignin recovered, the ethanol and residual heat being recycled into the lignin extractor. The delignified cellulosic pulp is removed from the lignin extractor and subjected to a milling operation to convert the pulp into a smooth sludge for entry to a bio-convertor by a super critical water process. The product from this convertor is hydrocarbon sludge with a principal component being a kerogen. In a separate process crude oil is extracted from this sludge and the residue is prepared as a high phosphate Fertilizer.

What is claimed is: 
     
         1 . A method for the processing of plant biomass comprising:
 treating plant biomass with an ethanol solution in a unit to extract lignin and generating a black liquor;   using the black liquor to heat ethanol solution entering the unit;   separating the lignin from the aqueous ethanol solution;   recovering and recycling the ethanol from the black liquor;   removing cellulosic residue generated after the lignin extraction;   
       producing a slurry from the cellulosic residue;
 feeding the slurry to a bio-convertor to convert the cellulosic and other cellular biological material into a hydrocarbon oil sludge; 
 using the heat from the hydrocarbon oil sludge to heat additional slurry entering the bioconverter; 
 recovering bio-crude from the hydrocarbon sludge by extraction; and 
 collecting residual sludge remaining after the extraction of bio-crude from the hydrocarbon sludge. 
 
     
     
         2 . The method of  claim 1  wherein the plant biomass is woody plant biomass. 
     
     
         3 . The method of  claim 2  further comprising drying the residual sludge to produce high phosphate fertilizer. 
     
     
         4 . The method of  claim 3  wherein the residual sludge is dried on a heated auger conveyor whereupon liquid both drains from the sludge and is vaporized. 
     
     
         5 . The method of  claim 4  wherein the vaporized liquid is drawn into a cooler for partial condensation to form condensed vapor. 
     
     
         6 . The method of  claim 5  wherein light hydrocarbon from the condensed vapor and liquid drained from auger is recycled. 
     
     
         7 . The method of  claim 2  wherein the woody biomass is selected from the group consisting essentially of plantation forestry, plantation crops such as vineyards, orchards, palm oil plantations, grasses, sawmills, wood fiber and urban waste 
     
     
         8 . The method of  claim 1  wherein the ethanol is aqueous and is 70% ethanol. 
     
     
         9 . The method of  claim 1  wherein the ethanol is aqueous and is 60-80% ethanol. 
     
     
         10 . The method of  claim 1  wherein the temperature in the unit is above 180 deg Celsius and the pressure is at least 23 bar. 
     
     
         11 . The method of  claim 1  wherein the temperature in the unit is above about 180 deg Celsius and the pressure is about 23 bar. 
     
     
         12 . The method of  claim 1  wherein ethanol is recovered from the black liquor with minimal loss of approximately 2% of the ethanol feed stream entering the unit. 
     
     
         13 . The method of  claim 1  wherein lignin is recovered from the black liquor by precipitation. 
     
     
         14 . The method of  claim 13  wherein the precipitation occurs by adding additional aerated water to the black liquor using a venturi mixing valve, whereby the lignin forms large crystals and float to a liquid surface. 
     
     
         15 . The method of  claim 1  wherein the cellulosic residue is reduced to slurry by milling and mixing with carrier powders. 
     
     
         16 . The method of  claim 15  wherein the carrier powders are selected from the group consisting essentially of salts of sodium, potassium and calcium as well as other carbohydrates such as algae, sugars, keratin, chitin, and collagen 
     
     
         17 . The method of  claim 1  wherein near supercritical water is produced in the bioconverter using residual heat from the bioconverter product. 
     
     
         18 . The method of  claim 17  wherein the temperature of the water is below 400° C. and the pressure is below 350 bar. 
     
     
         19 . The method of  claim 1  wherein the bio converter comprises co-axial annular pipes with an outer pipe being rated for higher pressure than the inside pipe, the inside pipe being configured for carrying feed through the outer pipe. 
     
     
         20 . The method of  claim 19  wherein a catalyst is mixed with the slurry fed to the bio converter. 
     
     
         21 . The method of  claim 20  wherein the catalyst is less than 5% of sodium carbonate. 
     
     
         22 . The method of  claim 1  wherein recovering the bio-crude comprises extracting the bio-crude in a counter current solvent extraction plant. 
     
     
         23 . The method of  claim 22  wherein the solvent used in the extraction plant is a light hydrocarbon solvent. 
     
     
         24 . The method of  claim 1  wherein residue from the bioconverter is removed by a dryer conveyor to recover the light hydrocarbon residue for reuse. 
     
     
         25 . A method for the processing of plant biomass comprising:
 extracting lignin from plant biomass using a solvent to generate a black liquor;   separating the lignin from the black liquor;   removing cellulosic residue generated after the lignin extraction;   producing a slurry from the cellulosic residue and optionally combining with other organic materials not containing lignin;   feeding the slurry to a bio-convertor to convert the cellulosic and other cellular biological material into a hydrocarbon oil sludge;   recovering bio-crude from the hydrocarbon sludge by extraction; and   sending residual sludge remaining after the extraction of bio-crude to a fertilizer plant to recover high phosphate fertilizer product.   
     
     
         26 . The method of  claim 25  wherein the fertilizer plant comprises a drying conveyor for use in drying fertilizer and a vapor recovery section for use in recovering liquid vaporized during drying. 
     
     
         27 . The method of  claim 26  wherein the vapor includes hydrocarbon. 
     
     
         28 . The method of  claim 25  wherein the fertilizer comprises potassium, magnesium, and nitrates. 
     
     
         29 . A method for the processing of plant biomass comprising:
 extracting lignin from plant biomass using a solvent to generate a black liquor;   separating the lignin from the black liquor;   removing cellulosic residue generated after the lignin extraction;   producing a slurry from the cellulosic residue;   feeding the slurry at high pressures to a bio-convertor to convert the cellulosic and other cellular biological material into a hydrocarbon oil sludge;   adjusting and equalizing pressures across valves in conditions of high gaseous content, by installing equalization cylinders upside down to enable surplus gas to be rapidly flushed out;   controlling valves proximate the bioconverter to rapidly open valves at the instant of minimum pressure difference between opposite sides of valves; and   recovering bio-crude from the hydrocarbon sludge by extraction.   
     
     
         30 . The method of  claim 29  further comprising sequentially operating equalization cylinders having slave pistons. 
     
     
         31 . A process for equalizing pressure of a flow stream across a valve comprising:
 providing a process valve having an abrasive flow stream with a first pressure on a pump side and a second pressure on a second side of the process valve;   providing a pump upstream from the pump side of said process valve;   providing a slave cylinder in fluid connection with the abrasive flow stream downstream from the second side of the process valve, wherein the fluid connection with the abrasive is connected to a top portion of the slave cylinder;   arranging a needle valve along a first non-abrasive fluid line between the pump and the slave cylinder; and   actuating the needle valve to permit flow between the slave cylinder and the pump, whereby, the first pressure with the second pressure are equalized.   
     
     
         32 . A system for equalizing pressure of a process flow stream across a valve comprising:
 a process valve having an abrasive flow stream with a first pressure on a first side and an abrasive flow stream with a second pressure on a second side;   a pump upstream from the first side of the process valve;   a slave cylinder in fluid connection with the abrasive flow stream downstream from the second side of the process valve, the fluid connection being connected to a top portion of the slave cylinder;   a valve disposed to control flow of a non-abrasive fluid line between the slave cylinder and the pump; and   wherein upon actuation of the needle valve, the fluid flow is permitted between the slave cylinder and the pump thereby equalizing the first pressure with the second pressure.   
     
     
         33 . A method for the processing of plant biomass comprising:
 extracting lignin from plant biomass using a solvent to generate a black liquor, the wood chips being fed to a top inlet of a counter current extraction column comprising a series of vertically aligned valves, and the solvent being fed into a bottom inlet of the counter current extraction column, the valves being operated sequentially to transfer wood chips down the column while providing cooking periods for extracting lignin;   opening a containment valve disposed at the top of the counter current extraction column, above a valve housing a top level cooking chamber of the column, to feed wood chips to the top inlet;   opening a containment valve downstream of valve that houses a bottom cooking chamber of the counter current extraction column, to remove pulp;   separating the lignin from the black liquor; and   recovering and recycling the solvent from the black liquor.   
     
     
         34 . A plant for processing plant biomass comprising:
 an extraction unit for extracting lignin from plant biomass;   a high pressure bioconverter reactor for converting residue from the extraction unit;   a plurality of pressure equalization cylinders fluidly connected to the bioconverter;   a control system for controlling at least one valve proximate the bioconverter to rapidly open the at least one valve at the instant of minimum pressure difference between opposite sides of the valve; and   a recovery section for recovering bio-crude from hydrocarbon sludge generated by the bioconverter.