Ammonia Sensor Using Gas Permeable Membrane and Conductivity Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sensors are unable to perform real-time, in situ, continuous monitoring of ammonia concentrations in aquatic, air, or agricultural environments, leading to inefficiencies in fertilizer use and environmental management.
Innovation Solution
A sensor system comprising a gas permeable membrane, a weak acid or base, and a conductivity detector that measures conductivity changes caused by ammonia reacting with the weak acid or base, allowing for real-time detection and monitoring of ammonia levels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional ammonia detection methods (Nessler method, fluorescence methods, chemiluminescence methods) are used, then ammonia concentration can be measured, but real-time continuous monitoring capability is lacking
Solution Approach 1:
The patent replaces traditional mechanical/chemical detection methods (Nessler reagent, fluorescence probes, chemiluminescence reactions) with an electrical measurement system. A conductivity sensor measures the electrical conductivity changes in the receiving phase, which are caused by ionic species generated from ammonia reaction with weak acid/base. This electrical measurement enables real-time continuous monitoring while maintaining measurement precision.
Solution Approach 2:
The patent introduces a receiving phase containing weak acid or weak base as an intermediary medium. Ammonia from the sample reacts with this intermediary to generate ionic species (ammonium ions or hydroxide ions), which then cause measurable conductivity changes. This intermediary enables the conversion of ammonia concentration into an easily measurable electrical signal for continuous monitoring.
2Quantity of substance
If fertilizer application is increased to ensure crop nutrition, then nutrient availability improves, but fertilizer waste and environmental pollution increase
Solution Approach 1:
The patent implements a feedback mechanism by continuously monitoring ammonia concentration in the environment using the conductivity-based sensor. This real-time data provides feedback on fertilizer loss rates, enabling dynamic adjustment of fertilizer application strategies. When ammonia levels indicate significant loss, the system can alert operators to reduce application rates or adjust timing, thereby minimizing fertilizer waste while ensuring adequate crop nutrition.
3Reliability
If in situ continuous monitoring is implemented, then real-time data for environmental management is obtained, but device complexity increases
Solution Approach 1:
The patent changes the measurement parameter from complex optical or chemical readings to simple electrical conductivity measurement. By monitoring conductivity changes in the receiving phase, the system achieves reliable in situ continuous monitoring with a relatively simple sensor structure. The conductivity sensor is a well-established, robust component that requires minimal calibration and maintenance, thus achieving reliability without excessive complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables accurate, sensitive, and reliable long-term monitoring of ammonia concentrations, reducing fertilizer waste and improving environmental management by providing immediate data for remedial actions.
Implementation Method 1
the membrane is permeable to target chemical species present in the sample
Implementation Method 2
target chemical species present in the sample permeate through the membrane
Implementation Method 3
target chemical species present in the sample permeate through the membrane and react with the weak acid or weak base thereby producing ionic species
Implementation Method 4
the ionic species changing the conductivity at the analytical side of the membrane
Data Source
AI summary
A sensor for the in situ detection of a target chemical species, comprising a gas permeable membrane having a sampling side and an opposing analytical side, wherein the sampling side of the membrane is capable of receiving a sample and the membrane is permeable to target chemical species present in the sample. A weak acid or a weak base is in contact with the analytical side of the membrane, and a conductivity detector is in contact with the weak acid or weak base. In use, target chemical species present in the sample permeate through the membrane and react with the weak acid or weak base, producing ionic species and changing the conductivity.