Special Use Permit No. PSP 25-033 is requesting to allow for a bioenergy facility to be constructed on a 5.00-acre portion of a 39.91-acre parcel located in the AE-20 (Exclusive Agricultural 20 Acre Minimum) Zone within the Rural Valley Lands Plan with a Land Use Designation of Valley Agriculture. The project consists of the installation and operation of three continuous pyrolysis reactors, side-by-side, to manufacture biochar from unusable portions of by-product almond shell generated at the Treehouse Almonds Huller (Treehouse) facility as well as well as by-product almond shell procured from local and regional almond huller/shellers through contractual agreements. The Project will be constructed at the Treehouse Almonds Huller facility located at 2115 Rd 144, Delano, Tulare County, California. The objectives of the Project are to manufacture biochar for use in vineyards and orchards, to generate renewable electricity and to develop Carbon Dioxide Removal Certificates (CORCs) for atmospheric carbon removal. The biochar will be used as a soil amendment to support regenerative agriculture in local and regional wine grape vineyards and almond and pistachio orchards. Almond shells are currently sold to dairies as dairy bedding, and to other buyers as a road base for dust control. When almond shell is used for these purposes, all absorbed carbon present in the shell is released into the atmosphere as that shell decomposes in a dairy or road base setting. When almond shells are chemically transformed into biochar and applied to soils, that carbon remains in the soil for millennia, and is not released into the atmosphere.
Utilizing pyrolysis heat from its reactors, Sitos can generate inexpensive renewable electricity. The Sitos Biochar Reactor system consists of three Carbon Powered Mineral Technology & Products (CPM) Continuous Pyrolysis units which will be used to process approximately 26,000 tons/year of almond shell, and the other to be procured from other local almond huller/shellers through contractual agreement. These 26,000 tons per year will produce roughly 8,000 tons/year of high-quality biochar that will be incorporated into local and regional wine grape vineyards and almond and pistachio orchards to facilitate regenerative agriculture. The Project will utilize existing loaders and other ancillary equipment associated with the current operations at the Treehouse Almonds Huller facility.
The Biochar Reactors are expected to operate approximately 8,000 hours per year with periods of shutdown approximately one-day every two weeks. During periods of shutdown, the units will be inspected and maintained, including regular maintenance of all valves, moving parts, and thermocouples. During operations, up to 40 gallons per hour of water will be used for temperature control and quenching within each unit (up to 320,000 gallons per year based on maximum operation of 8,000 hours per year). Water will be delivered to the 5,000-gallon water tank on site. After each maintenance period, the units will be restarted which requires a maximum of 26 gallons of propane per startup cycle. Accordingly, assuming 26 startup cycles for each of the three reactors per year, Project operations will require approximately 2,028 gallons of propane.
DATE RECEIVED FOR FILING AT TULARE COUNTY CLERKS OFFICE
The Sitos Biochar Reactor process is characterized as Slow-Pyrolysis, a process in which biomass material is heated in an oxygen-deficient atmosphere within an enclosed kiln. This process results in the production of process exhaust gas and a carbon-rich solid product (biochar). The feedstock biomass will be made up of cellulose, hemicellulose, and lignin, in this case, almond shell. Cellulose and hemicellulose evaporate almost completely at temperatures above 500°C (932°F), while up to 50% of the lignin also volatilizes. The volatile components of biomass consist mainly of different hydrocarbon compounds. When these compounds are released during the pyrolysis process, they are mixed with air and spontaneously combust to provide the heat to continually sustain the process, avoiding the need for external fuel sources to be relied upon. As such, the Biochar Reactors will be self-sustaining except for minimal electricity and water requirements.
Temperature, pressure, and air/oxygen levels in the Biochar Reactor are regulated using water injection and air intake controls and are optimized for each individual feedstock. The syngas produced in the process is burnt off prior to passing through the exhaust stack. Conceptually, there are two horizontal chambers within each Biochar Reactor themselves. These include a trough through which the biomass is transported, and a reactor zone that is situated above the biomass trough. With the slight upward vacuum effect and airflow direction, the feedstock passed through the reactor in an oxygen limited or oxygen free environment.
At its operating temperatures around 750°C, the Biochar Reactor unit forces biomass into releasing flammable volatiles, which are then combusted just above the biomass as it moves through the trough. While conversion of the volatiles is maximized through the addition of process air in the combustion zone, surface reactions of the biomass itself are kept to a minimum. Specifically, feedstock biomass is substantially chemically altered through the thermo-decomposition process. What leaves the system is almost pure carbon; therefore, it has been determined that this project will not have a significant effect on the environment.
Construction for this project includes a proposed building on a less the 5-acre portion of a 39.91-acre parcel, a 20,000 sq. ft. metal building with a 650 sq. ft. entry canopy and a 2,500 sq. ft. canopy, for a total of 23,150 sq. ft. which will house the main activities of the facility. It will also include the construction of a 1,350 sq. ft. receiving pit canopy which will be used to keep rainwater out of the receiving pits, a 400 sq. ft. fire pump house, a 100 sq. ft. guard shack, and a 716 sq. ft. architectural canopy. Portions of the buildings purpose includes holding the three pyrolysis reactors, as well as the control room, office, breakroom, and restrooms for employees.
