System for co-firing coal and beneficiated organic-carbon-containing feedstock in a coal combustion apparatus

• US 9,683,738 B2
• Filed: 02/17/2015
• Issued: 06/20/2017
• Est. Priority Date: 06/16/2014
• Status: Active Grant

• Current Assignee: CTP Biotechnology, LLC
• Original Assignee: Biomass Energy Enhancements LLC.
• Inventors: Tait, Carleton Drew, Catto, Michael L, Van Thorre, Doug M, Scalzo, Philip James
• Primary Examiner(s): Toomer, Cephia D
• Application Number:
  US14/624,109
• Publication Number:
  US 20150362179A1
• Time in Patent Office: 854 Days
• CPC Class Codes: C10L 2200/0469 Renewables or materials of biological origin
• CPC Class Codes: C10L 2290/02 Combustion or pyrolysis
• CPC Class Codes: C10L 2290/06 Heat exchange, direct or indirect
• CPC Class Codes: C10L 2290/08 Drying or removing water
• CPC Class Codes: C10L 2290/28 Cutting, disintegrating, shredding or grinding
• CPC Class Codes: C10L 2290/30 Pressing, compressing or compacting
• CPC Class Codes: C10L 5/08 without the aid of extraneous binders briquetting peat C10F
• CPC Class Codes: C10L 5/143 with lignin-containing products
• CPC Class Codes: C10L 5/361 Briquettes
• CPC Class Codes: C10L 5/363 Pellets or granulates
• CPC Class Codes: C10L 5/447 Carbonized vegetable substances, e.g. charcoal, or produced by hydrothermal carbonization of biomass
• CPC Class Codes: C10L 9/08 by heat treatments, e.g. calcining
• CPC Class Codes: F23B 10/00 Combustion apparatus characterised by the combination of two or more combustion chambers
• CPC Class Codes: F23B 2700/023 with various arrangements not otherwise provided for
• CPC Class Codes: F23B 50/12 the fuel being fed to the combustion zone by free fall or by sliding along inclined surfaces, e.g. from a conveyor terminating above the fuel bed
• CPC Class Codes: F23D 1/00 Burners for combustion of pulverulent fuel disposition of burners F23C
• CPC Class Codes: F23D 2204/00 Burners adapted for simultaneous or alternative combustion having more than one fuel supply
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel
• CPC Class Codes: Y02E 50/30 Fuel from waste, e.g. synthetic alcohol or diesel

Abstract

A co-firing process is described using coal and processed biomass to reduce adverse by-products in a coal combusting apparatus. The coal feedstock is selected from coal, a coal substitute processed biomass, or an aggregate blend of coal and processed biomass. The biomass feedstock comprises processed biomass pellets. The total energy density is predetermined and can be similar to the coal component or higher than the coal component. The intracellular salt in the processed biomass is at least 60 wt % less for the processed organic-carbon-containing feedstock used to make the processed biomass pellets than that of the starting un-processed processed organic-carbon-containing feedstock.

Claims

1. A co-firing system for combusting coal in a coal combusting apparatus with less adverse by-products;

comprising;

a first chamber of a coal combusting apparatus configured to pulverize coal and feed it into the coal combusting apparatus;

a second chamber of a coal combusting apparatus configured to pulverize processed biomass pellets from a processed biomass system and feed them into the coal combusting apparatus,

wherein the ratio, of pulverized coal to pulverized processed biomass pellets in the coal combusting apparatus is between 1 to 9 and 9 to 1 by weight, and

wherein the processed biomass system is configured to make processed biomass from unprocessed organic-carbon-containing feedstock that includes free water, intercellular water, intracellular water, intracellular water-soluble salts, and at least some plant cells comprising cell walls that include lignin, hemicellulose, and microfibrils within fibrils, the processed biomass system;

comprising;

a beneficiation sub-system configured to convert the unprocessed organic-carbon-containing feedstock into a processed organic-carbon-containing feedstock with characteristics that include having an energy density of at least 17 MMBTU/ton (20 GJ/MT), a water content of less than 20 wt %, and a water-soluble intracellular salt content that is decreased more than 60 wt % on a dry basis from that of the unprocessed organic-carbon-containing feedstock; and

a pelletizing sub-system to convert the processed organic-carbon-containing feedstock into processed biomass pellets.

2. The co-firing system of claim 1, wherein a blended aggregate is made in a blending sub-system comprising:

a sizing chamber to properly sized particles of coal and processed biomass to a similar size;

a combining chamber configured to blend the similarly sized particles into a blended powder of a predetermined ratio of coal to processed biomass; and

a compacting chamber to compress the blended powder into blended compact aggregates,

wherein the pelletizing sub-system comprises;

a compression chamber configured to separate the processed organic-carbon-containing feedstock into discrete units of mass having a longest length of at least 0.16 inch (0.41 cm) and a density of at least 37.5 pounds per cubic foot (0.60 grams per cubic centimeter) to form processed biochar pellets; and

a collection chamber configured to gather aggregates of processed biochar pellets.

3. The co-firing system of claim 2, wherein the processed biomass is processed biochar, the blended compact aggregate has an energy density of at least 21 MMBTU/ton (25 GJ/MT), the processed organic-carbon-containing feedstock is passed through a heating sub-system to form processed biochar that is blended with coal into a blended compact aggregate in a blending sub-system, and the water-soluble intracellular salt content decrease is based on comparing the processed organic-carbon-containing feedstock before it is passed through the heating sub-system to the unprocessed organic-carbon-containing feedstock.

4. The co-firing system of claim 2, wherein the beneficiation sub-system comprises:

a transmission device configured to convey into a reaction chamber unprocessed organic-carbon-containing feedstock comprising free water, intercellular water, intracellular water, intracellular water-soluble salts, and at least some plant cells comprising cell walls that include lignin, hemicellulose, and microfibrils within fibrils;

at least one reaction chamber comprising at least one entrance passageway, at least one exit passageway for fluid, at least one exit passageway for processed organic-carbon-containing feedstock, and at least three sections, the sections comprising;

a wet fibril disruption section configured to interact with at least some of the lignin and hemicellulose between the fibrils to make at least some regions of the cell wall more susceptible to penetration by water-soluble salts without dissolving more than 25 percent of the lignin and hemicellulose;

a vapor explosion section in communication with the wet fibril disruption section and at least configured to volatilize plant fibril permeable fluid through rapid decompression to penetrate the more susceptible regions of the cell wall so as to create a porous organic-carbon-containing feedstock with plant cell wall passageways for intracellular water and intracellular water-soluble salts to pass from the plant cell; and

a compaction section in communication with the vapor explosion section and configured to compress the porous organic-carbon-containing feedstock between pressure plates configured to minimize formation of water-impermeable felt so as to permit the escape of intracellular water and intracellular water-soluble salt from the reaction chamber fluid exit passageway and to create processed organic-carbon-containing feedstock that passes out through its reaction chamber exit passageway; and

a collection device in communication with the reaction chamber and configured to gather the processed organic-carbon-containing feedstock having a water content of less than 20% by weight, a combined lignin and hemicellulose content that is decreased by at least 25% on a dry basis from that of the unprocessed organic-carbon-containing feedstock, and a water-soluble intracellular salt content that is decreased by at least 60% on a dry basis from that of the unprocessed organic-carbon-containing feedstock.

5. The co-firing system of claim 3, wherein the heating sub-system is an oxygen-deprived thermal sub-system comprises a reaction chamber configured to heat processed organic-carbon-containing feedstock in an atmosphere that contains less than 4 percent oxygen to a temperature sufficient to convert at least some processed organic-carbon-containing feedstock into processed biogas and processed biochar.

6. The co-firing system of claim 5, wherein the oxygen-deprived thermal sub-system is from a group consisting of

a horizontal sublimation system comprising:

a hot box configured to be able to heat from an ambient temperature to an operating sublimation temperature, maintain an initial operating sublimation temperature and a final operating sublimation temperature that are stable within less than ±

10°

C., and cool from operating sublimation temperatures to an ambient temperature without leaking any oxygen into the hot box and having at least one heat source in communication with the interior of the hot box to supply heat as needed;

at least one horizontal reaction chamber largely located within the hot box, having a surface, configured to heat the processed organic-carbon-containing feedstock without external catalyst or additional water to an operating sublimation temperature in a time frame that is short enough to sublime at least part of the processed organic-carbon-containing feedstock without creating any liquid, configured to heat from an ambient temperature to an operating sublimation temperature, operate at a sublimation temperature, and cool from a operating sublimation temperature to an ambient temperature without leaking any product gas fuel into the surrounding hot box, and comprising an input end outside the hot box and configured to receive compressed feedstock through an input line and an output end outside the hot box and configured to discharge product gas fuel gas through a discharge line and solid char fuel through an output line;

a first powered transport mechanism that is located within the reaction chamber and is configured to convey sublimation products of the processed organic-carbon-containing feedstock through the reaction chamber as the processed organic-carbon-containing feedstock is transformed into processed biogas and processed biochar; and

a gas-tight element on both the input line and output line and configured to prevent hot biogas from adversely escaping from the reaction chamber;

or

a vertical sublimation system, comprising;

at least vertical reaction chamber configured to heat the processed organic-carbon-containing feedstock without external catalyst or additional water, carbon dioxide, or carbon monoxide, to an operating sublimation temperature in a time frame that is short enough to sublime at least part of the processed organic-carbon-containing feedstock without creating any liquid;

a first powered transport mechanism that is located partly within the reaction chamber, has an extended part that extends outside the reaction chamber, and is configured to convey sublimation products of the processed organic-carbon-containing feedstock through the reaction chamber as the processed organic-carbon-containing feedstock is transformed into biogas and processed biochar; and

a self-adjusting seal that is configured to continuously contain the processed biogas within the reaction chamber at the region surrounding the extended part of the powered transport mechanism during changing temperatures of startup and shutdown operations, and during steady-state sublimation temperature during operation.

7. The co-firing system of claim 3, wherein the heating sub-system is a microwave sub-system comprising:

at least one reaction chamber within a microwave reflecting enclosure, the reaction chamber comprising at least one microwave-transparent chamber wall and at least one reaction cavity within the reaction chamber that is configured to hold the organic-carbon-containing feedstock in an externally supplied oxygen free atmosphere;

a microwave subsystem comprising at least one device configured to emit microwaves when energized, the microwave device positioned relative to the reaction chamber so that the microwaves are directed through the microwave-transparent chamber wall and into the reaction cavity; and

a mechanism configured to provide relative motion between the microwave device and the reaction chamber.

8. The co-firing system of claim 4, wherein the vapor explosion section of the beneficiation sub-system further comprises a wash element that is configured to remove and clean microparticles of unprocessed organic-carbon-containing feedstock, lignin fragments, and hemicellulosic fragments from the vapor explosion section into a fine, sticky mass of biomass with high lignin content,

wherein a blending chamber of the blending sub-section is further configured to receive fine, sticky mass of biomass to permit lower temperatures in a compaction chamber formation during formation of blended compact aggregates.

9. The co-firing system of claim 4, wherein the processed organic-carbon-containing feedstock has a water soluble intracellular salt content that is decreased by more than 75 wt % on a dry basis from that of unprocessed organic-carbon-containing feedstock and the compaction section of the beneficiated sub-system is configured to provide at least one rinsing step.