Static mixing device for LPG and biogas conditioning

Abstract

This utility model discloses a static mixing and conditioning device for LPG and biogas, belonging to the field of gas mixing technology. The device includes a main pipeline, an LPG supply pipeline, and a unique jet mixing structure. The jet mixing structure has two rows of functionally differentiated jet orifices for achieving rapid and uniform mixing of LPG and biogas. The device is characterized by integrating an automatic control assembly composed of physical components, including sensors installed on the pipeline, a central controller, and an electric regulating valve installed on the LPG pipeline. These components are physically connected and transmit signals through circuitry, enabling the device to automatically adjust the LPG injection rate based on real-time monitored gas parameters, ensuring a stable calorific value of the mixed gas. This utility model solves the technical challenges of biogas grid connection through a purely physical structure and electromechanical integration, offering reliable structure and precise control.

Description

Technical Field

[0001] This utility model belongs to the field of gas mixing technology, and more specifically relates to a static mixing and conditioning device for mixing liquefied petroleum gas (LPG) with biogas to replace natural gas. Background Technology

[0002] Biogas, as a clean and renewable energy source, plays an important role in waste resource utilization and rural energy structure. However, the promotion and application of biogas faces technical bottlenecks due to unstable yield and composition. Affected by factors such as raw materials, temperature, and fermentation conditions, biogas yield fluctuates greatly, and the content of its main component, methane, typically varies between 50% and 70%, resulting in unstable calorific value.

[0003] Currently, the main ways to utilize biogas include combined heat and power (CHP) and direct combustion heating. CHP has low power generation efficiency, typically only 30%-35% for small power plants; direct combustion heating, due to fluctuations in calorific value, requires frequent adjustments to combustion parameters, resulting in unstable thermal efficiency, and incomplete desulfurization can easily cause secondary pollution. These drawbacks limit the application value of biogas as a high-quality fuel, making it difficult to directly integrate it into natural gas pipeline networks with strict quality requirements.

[0004] Therefore, how to effectively improve the energy quality of biogas so that it can be used stably and efficiently is an urgent problem to be solved in the field of renewable energy. Summary of the Invention

[0005] The purpose of this invention is to provide a static mixing and conditioning device for LPG and biogas, which aims to solve the technical problem that biogas is difficult to integrate into the natural gas pipeline network due to unstable composition and output in the prior art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: A static mixing and conditioning device for LPG and biogas includes a main pipeline, an LPG supply pipeline, and a jet mixing structure. The jet mixing structure is installed on the main pipeline and includes a first row and a second row of jet orifices arranged along the biogas flow direction. A key improvement of this device is the inclusion of an automatic control component, which consists of physical hardware including: a flow sensor and a gas composition sensor installed on the main pipeline; an electrically controlled regulating valve installed on the LPG supply pipeline; and a central controller. Physically, the input of the central controller is electrically connected to the sensors, and its output is electrically connected to the electrically controlled regulating valve. This combination allows the central controller to automatically and physically drive the electrically controlled regulating valve based on real-time gas parameters collected by the sensors, thereby precisely controlling the LPG blending amount and ensuring the stability of the final mixed gas quality.

[0007] Preferably, the jet axis of the first row of jet holes points towards the inner wall region of the main pipe, which is used to disrupt the pipe boundary layer and promote the mixing of biogas in the edge region.

[0008] Preferably, the jet axis of the second row of jet holes points to the central region of the main pipe to eliminate the central flow dead zone and achieve uniform mixing of the pipe cross section.

[0009] Preferably, the number of the first row of jet orifices is greater than the number of the second row of jet orifices, in order to enhance the disturbance and mixing effect on the boundary layer region.

[0010] Preferably, at least one pressure reducing valve is installed upstream of the electric regulating valve on the LPG supply pipeline to reduce the pressure of high-pressure gaseous LPG before supplying it to the electric regulating valve, thereby ensuring stable LPG injection pressure. Specifically, the pressure reducing valve has a two-stage pressure reducing structure, including a first-stage pressure reducing valve that reduces the LPG pressure to 0.6-0.8 MPa and a second-stage pressure reducing valve that further reduces the LPG pressure to 0.2-0.4 MPa.

[0011] Preferably, the gas composition sensor is an online gas chromatograph, and its installation position is downstream of the jet mixing structure; the online gas chromatograph is set downstream of the jet mixing structure to monitor the composition of the mixed gas in real time and provide feedback data for the closed-loop regulation of the central controller.

[0012] Preferably, the device further includes an audible and visual alarm and an emergency shut-off valve electrically connected to the central controller; the central controller is configured to: drive the audible and visual alarm when a preset alarm condition is detected, and control the emergency shut-off valve to cut off the gas supply when a preset dangerous condition is detected.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1. Ingenious structural design and high mixing efficiency: By setting two rows of jet holes with different functions, the first row of holes breaks the boundary layer and the second row of holes eliminates the central dead zone, realizing rapid and uniform mixing of LPG and biogas on the pipeline cross section. No additional mechanical stirring parts are required. The structure is simple and reliable and has low energy consumption.

[0014] 2. Intelligent closed-loop control ensures stable gas quality: The hardware closed-loop structure consisting of sensors, controllers, and actuators can adjust the LPG blending ratio in real time and accurately according to changes in biogas flow and composition, ensuring that key indicators such as the calorific value and Wobbe index of the final output mixed gas remain constant and meet the standards of natural gas pipeline networks.

[0015] 3. High safety and reliable operation: The device has no moving parts, resulting in a low failure rate. Through integrated safety hardware and control connections, it can provide early warnings for abnormal operating conditions and execute emergency shutdowns, ensuring production safety.

[0016] 4. Enhancing the value of renewable energy, economic and environmental benefits: Converting low-quality and unstable biogas into high-quality and standardized fuel gas significantly increases the utilization value of biogas, reduces the consumption of fossil energy and carbon emissions, and has significant economic benefits and environmental significance. Attached Figure Description

[0017] This disclosure includes accompanying drawings, which are to be considered included in and form part of the specification, and together with the specification illustrate various exemplary embodiments, features, and aspects of the disclosure and serve to explain the principles of the disclosure. The invention will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings. Wherein: Figure 1 This is a schematic diagram of the structure of a mixing and conditioning device according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the jet hole arrangement and mixing principle in the mixing and conditioning device of this utility model; In the diagram: 1-Main pipeline; 2-LPG supply pipeline; 3-Jet mixing structure; 31-First row of jet orifices; 32-Second row of jet orifices. Detailed Implementation

[0018] To more clearly illustrate the technical solutions of the embodiments in this specification, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this specification. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0019] like Figures 1 to 2 As shown, the present invention provides a static mixing and conditioning device for LPG and biogas, which mainly consists of a main pipeline 1, an LPG supply pipeline 2, a jet mixing structure 3, and a set of automatic control components.

[0020] In this embodiment, purified biogas from the biogas plant is desulfurized and dehydrated before entering the main pipeline 1.

[0021] LPG supply line 2 is used to transport gaseous LPG. Liquid LPG is first vaporized in a vaporizer (not shown in the figure), and then its pressure is reduced by a two-stage pressure-reducing valve. The first-stage valve reduces the pressure to 0.6-0.8 MPa, and the second-stage valve further reduces the LPG pressure to 0.2-0.4 MPa to obtain a stable LPG source pressure. The reduced-pressure LPG then flows through an electrically controlled regulating valve and finally enters the jet mixing structure.

[0022] The jet mixing structure 3 is the core component of this device, such as... Figure 1 and Figure 2 As shown. It is located at the connection between the LPG supply pipeline and the main pipeline, and includes a first row of jet holes 31 and a second row of jet holes 32 distributed along the biogas flow direction. The jet holes are evenly distributed on the pipe wall of the main pipeline 1 and connected to the LPG supply pipeline 2. According to the design, the jet axis of the first row of jet holes 31 points to the area near the inner wall of the main pipeline 1, and the LPG gas it sprays mainly acts on the area near the inner wall of the main pipeline 1, with the purpose of strongly disturbing and breaking the boundary layer with low flow velocity, so that the biogas at the edge is fully premixed with LPG. The number of the first row of jet holes 31 can be designed to be more than that of the second row to enhance the disturbance effect. The jet axis of the second row of jet holes 32 points to the central area of ​​the main pipeline 1, and its high-speed jet can penetrate the mainstream and eliminate the flow dead zone in the center of the pipeline. Through this design of combining internal and external jets and targeted regional mixing, it can be ensured that LPG is uniformly mixed with biogas across the entire pipeline cross-section within a very short distance.

[0023] The automatic control component of this device is a key physical structure for achieving precise mixing, and its composition and connection relationships are as follows: Sensing components: On the main pipeline 1, a turbine flow meter or ultrasonic flow meter (as a flow sensor) for measuring the flow rate of biogas, and an online gas chromatograph (as a gas composition sensor) for analyzing gas components are installed, both for monitoring gas parameters within the pipeline. The signal output terminals of these sensors are physically connected to the input interface of the central controller via signal cables. The online gas chromatograph is preferably installed downstream of the jet mixing structure to detect the parameters of the mixed gas.

[0024] Actuation component: An electrically operated regulating valve is installed on LPG supply line 2. The valve's actuator is electrically connected to the output interface of the central controller.

[0025] The core control component is the central controller, whose hardware can be a programmable logic controller (PLC) or an embedded microcontroller system. As a physical entity, it internally includes a processor, memory, and input / output (I / O) interfaces. It receives electrical signals from the sensing components, processes and calculates them through its internal circuitry, and then outputs a control signal to the electric regulating valve via its output interface. The central controller's input terminals are electrically connected to the flow sensor and the gas composition sensor, and its output terminals are electrically connected to the electric regulating valve. The central controller receives signals transmitted by the sensors and generates control signals accordingly to drive the electric regulating valve.

[0026] The device operates through the collaboration of its various physical components: During operation, flow sensors and gas composition sensors continuously transmit detected physical signals (such as pulse signals, voltage, or current signals) to the central controller. The central controller processes these input signals according to its internally programmed logic, calculates the LPG flow rate required to achieve the target mixing ratio, and converts it into a specific control signal (such as a 4-20mA current signal) output to the electric regulating valve. Upon receiving this signal, the actuator of the electric regulating valve physically changes the valve opening, thereby precisely regulating the LPG injection amount and achieving dynamic, closed-loop control of the mixing ratio.

[0027] For safety protection, this device is also equipped with audible and visual alarms and emergency shut-off valves (such as quick-closing solenoid valves installed on the LPG and biogas main lines). These safety hardware components are also electrically connected to designated output ports of the central controller. When the central controller receives a signal from the sensor indicating an abnormal operating condition (such as excessively low methane content or sudden pressure changes), its internal logic drives the corresponding output port, thereby physically triggering the audible and visual alarm to sound an alarm, or, in more serious cases, directly driving the emergency shut-off valve to close, cutting off the gas supply and ensuring the safety of the device and personnel.

[0028] In summary, this utility model, through its unique dual-row jet orifice static mixing structure and combined with an automatic control hardware combination consisting of physical components such as sensors, controllers, and actuators, can efficiently and uniformly mix unstable biogas with LPG to produce stable gas that meets the standards of natural gas pipeline networks, providing a reliable technical solution for the high-value utilization of renewable energy sources such as biogas.

[0029] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, and the scope of the present invention is not limited to the embodiments described above. Many modifications and variations will be apparent to those skilled in the art without departing from the spirit and scope of the invention. That is, those skilled in the art can make various changes and improvements to the present invention in form and detail, and all of these are considered to fall within the protection scope of the present invention. The terminology used herein is chosen to best explain the principles, practical applications, or improvements to the technology in the market of the various embodiments, or to enable those skilled in the art to understand the embodiments disclosed herein.

Claims

1. A static mixing and conditioning device for LPG and biogas, characterized in that, include: A main pipeline (1) is used to transport biogas; An LPG supply pipeline (2) is connected to the main pipeline; A jet mixing structure (3) is provided at the connection between the LPG supply pipeline and the main pipeline. The jet mixing structure includes a first row of jet holes (31) and a second row of jet holes (32) arranged sequentially along the flow direction of biogas in the main pipeline. The jet holes are evenly distributed on the pipe wall of the main pipeline (1) and are connected to the LPG supply pipeline (2). A flow sensor and a gas composition sensor are installed on the main pipeline (1) to monitor the gas parameters in the pipeline; An electric regulating valve is installed on the LPG supply line (2); A central controller is provided, wherein the input terminal of the central controller is electrically connected to the flow sensor and the gas composition sensor, and the output terminal is electrically connected to the electric regulating valve. The central controller is used to receive the signals transmitted by the sensors and generate control signals accordingly to drive the electric regulating valve to operate.

2. The LPG and biogas static mixing and conditioning device according to claim 1, characterized in that, The jet axis of the first row of jet holes (31) points to the inner wall region of the main pipe (1).

3. The LPG and biogas static mixing and conditioning device according to claim 1 or 2, characterized in that, The jet axis of the second row of jet holes (32) points to the central region of the main pipe (1).

4. The LPG and biogas static mixing and conditioning device according to claim 1, characterized in that, The number of the first row of jet orifices (31) is greater than the number of the second row of jet orifices (32).

5. The LPG and biogas static mixing and conditioning device according to claim 1, characterized in that, At least one pressure reducing valve is provided on the LPG supply pipeline (2) upstream of the electric regulating valve.

6. The LPG and biogas static mixing and conditioning device according to claim 5, characterized in that, The pressure reducing valve has a two-stage pressure reducing structure, including a first-stage pressure reducing valve and a second-stage pressure reducing valve.

7. The LPG and biogas static mixing and conditioning device according to claim 1, characterized in that, The gas composition sensor is an online gas chromatograph, and it is installed downstream of the jet mixing structure (3).

8. The LPG and biogas static mixing and conditioning device according to claim 1, characterized in that, The device also includes an audible and visual alarm and an emergency shut-off valve electrically connected to the central controller; the central controller is configured to: drive the audible and visual alarm when a preset alarm condition is detected, and control the emergency shut-off valve to cut off the gas supply when a preset dangerous condition is detected.

Images