Total Mill Flow Determination in Biofuel Slurry Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing biofuel production processes lack accurate measurement of total mill flow due to uncontrolled influences such as feedstock moisture content and flowability, affecting the efficiency and accuracy of the biofuel production process.
Innovation Solution
A system and method that utilize sensors to measure biomass slurry flow, slurry density, backset flow, and backset density, along with composition values, to determine total mill flow by calculating the quantity of biomass solids and water in the slurry and backset, accounting for time delays and lags using a system filter, and storing the determined total mill flow for use in model predictive control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If rotary pocket feeders are used to regulate feedstock flow, then the feeding process can be controlled, but the measurement accuracy of total mill flow deteriorates due to uncontrolled influences such as moisture content and flowability
Solution Approach 1:
The patent introduces an intermediary measurement system that indirectly measures total mill flow by measuring the slurry flow downstream and calculating the feedstock flow based on material balance. This intermediary approach bypasses the direct measurement problem at the feeder while still providing accurate flow data through the relationship: feedstock flow = slurry flow - backset flow
Solution Approach 2:
The system implements feedback by continuously measuring slurry flow and backset flow, then using these measurements to calculate and control the total mill flow. The measured values are fed back to the control system to adjust the milling process, ensuring accurate flow measurement despite variations in moisture content and feedstock properties
2Device complexity
If estimated flow values are used based on feeder capacity and rotation rates, then the system operation is simple, but the accuracy of process efficiency determination deteriorates
Solution Approach 1:
The patent replaces the mechanical estimation method (based on feeder capacity and rotation rates) with a measurement-based system using flow meters and density meters. This substitution transitions from mechanical estimation to instrumental measurement, significantly improving accuracy while adding moderate system complexity
Solution Approach 2:
The system changes the measurement parameters from mechanical (rotation rate, capacity) to physical properties (flow rate, density, composition). By measuring actual physical parameters of the slurry and backset, the system achieves accurate determination of total mill flow and process efficiency
3Device complexity
If time delays and lags are not accounted for in measurements, then the measurement system is simpler, but the accuracy of total mill flow determination deteriorates
Solution Approach 1:
The system applies preliminary action by using a system filter to pre-process the measured values and compensate for time delays and lags before calculating the total mill flow. This preliminary filtering ensures that the calculated flow values accurately reflect the current process state, accounting for the inherent delays in measurement and material transport
Data Source
AI summary
System and method for determining total mill flow (TMF) in a biofuel production process. Measured slurry flow and density values from a process fed by mill(s), backset, and at least one water source, are received. The slurry includes biomass solids and water. Measured backset flow and density values, and a backset composition value are received, as well as a slurry composition value indicating % biomass solids of the slurry is received. A quantity of biomass solids and/or water of the slurry determined based on the slurry flow, density, and composition, and a quantity of the biomass solids and/or water of the backset determined based on the backset flow and density, backset composition, and a system filter characterizing time delays and lags between measurements of the backset flow and biomass slurry flow. Total mill flow is determined based on the quantities of biomass solids and/or water of the slurry and backset.