Project NameA city's straw comprehensive utilization industrial park

project orientation:DomesticHigh value utilization of straw "four element separation" (cellulose/hemicellulose/lignin/nutrients)

Total investment:500 million yuan (total planning of 3 billion yuan, with the first phase focusing on core production lines)

Land occupation:133200 square meters (total planned 260000 square meters)

Production capacity:Annual processing of 20000 tons of corn stover

The core process of this project is the separation of four elements from straw, and the electromagnetic flowmeter is the core and widely used flow measurement instrument in the entire process of the project. It is mainly suitable for measuring corrosive media, media containing slight fibers/suspended particles, large-diameter process water/wastewater, etc., covering core sections such as pretreatment, separation, public engineering, and environmental protection. It provides accurate flow data support for material water ratio control, solvent ratio, energy consumption accounting, and environmental compliance. It is one of the key instruments to ensure the stability of mild hydrolysis and multi-stage separation processes.

1、 Core application section and measurement medium(Divided by process flow)

The application matching project of electromagnetic flowmeter is the process logic of "straw pretreatment and mild hydrolysis four element separation public engineering environmental protection treatment". Different sections make targeted selection of electrodes, liners, and diameters due to differences in medium characteristics.

2、 Key points of core selection(Adapt to project media and process characteristics)

The selection of electromagnetic flow meters for this project is based on the core principles of "corrosion resistance, anti blocking, anti hanging, and adaptability to low/medium temperature working conditions", combined with the characteristics of different sections of the medium. Differentiated configurations are made in electrode materials, lining materials, excitation methods, and protection levels to avoid measurement pain points such as straw slurry fiber blockage, weak acid medium corrosion, and suspended particle wear. The selection parameters all comply with the national standard for industrial automation instruments (GB/T 18659-2018) and the project's explosion-proof and environmental protection requirements. The specific key selection items are as follows:

1. Electrode material:

316L stainless steelUsed for clean/weak impurity media such as process water, circulating water, softened water, and ground flushing water, suitable for public engineering and environmental treatment sections, with high cost-effectiveness and resistance to slight oxidation and corrosion;

HastelloyUsed for media containing trace amounts of corrosive/suspended particles such as straw hydrolysate, weak acid extractant, ionic liquid dilute solution, etc., suitable for pretreatment and four element separation stages, resistant to pitting corrosion and wear, avoiding electrode polarization caused by medium adsorption.

2. Lining material (anti blocking/anti hanging material/heat-resistant core)

In response to the characteristics of the straw fiber medium in the project, such as easy hanging, medium temperature in the hydrolysis section (≤ 160 ℃), and weak acid/weak alkali in the cleaning solution, polytetrafluoroethylene (PTFE/Teflon) and chloroprene rubber (CR) are preferred for lining to prevent measurement drift caused by lining detachment and hanging.

3. Excitation method and accuracy (adapted to process control requirements)

The accuracy requirements for electromagnetic flow meters in the project are graded according to the importance of the process in each section, and the excitation method is selected accordinglyLow frequency rectangular wave excitationStrong anti-interference ability, suitable for complex electromagnetic environments in industrial sites

4. Protection/Explosion proof Level (Suitable for Workshop Site Environment)

Based on the environmental characteristics of the project workshop, standardize the configuration of protection and explosion prevention to meet the safety requirements of the chemical/light industry:

Protection levelUnified electromagnetic flowmeter for the entire projectIP67Some instruments installed outdoors (such as circulating water stations and environmental treatment areas) have been upgraded toIP68To prevent rainwater and dust from entering the instrument body and causing circuit faults;

Explosion-proof rating: OnlyElectromagnetic flowmeter configuration Exd II BT4 for four element separation section (including extractant/trace organic solvent)Explosion proof grade, other sections are non explosion proof, which not only meets the safety requirements of the explosion-proof area, but also avoids excessive configuration and increased costs.

5. Signal output and communication (adapted to project automation systems)

All electromagnetic flow meters support4-20mA analog output+HART protocolSome large-diameter instruments (DN200 and above) have increasedModbus-RTUProtocol, directly integrated into the projectDCS control system (centralized monitoring in the central control room)

Core highlights of process adaptation(Different from traditional straw projects)

The application of electromagnetic flowmeter in this project is not simply "flow measurement", butOriginal technology for separating four elements from straw at a certain universityIt has solved the pain points of "measurement drift, easy blockage, and short service life" of electromagnetic flow meters in traditional straw utilization projects. The core highlights are reflected in two aspects:

Parameter control adapted to the "mild hydrolysis" processThe precision requirements for controlling the material to water ratio in a mild hydrolysis process (120-160 ℃, micro positive pressure) at a certain university have been approvedHigh precision electromagnetic flowmeter+DCS closed-loop controlThe fluctuation range of the material to water ratio is controlled within ± 0.2 to avoid component degradation caused by high temperature and high pressure, ensuring a cellulose purity of ≥ 91.6% and a hemicellulose extraction rate of ≥ 85%, achieving precise conversion from laboratory processes to industrial production;

2 Adapt to the environmental goal of "zero waste and full utilization"Electromagnetic flowmeter for the environmental protection section of the projectWastewater treatment system, process water circulation systemLinkage, through precise measurement of wastewater flow and circulating water reuse flow, achieves "no discharge" of wastewater and process waterReuse rate ≥ 95%This not only reduces the water resource consumption of the project, but also meets the environmental protection policy requirements for the comprehensive utilization of straw in Jilin Province, providing data support for the project to strive for green subsidies.

Application Summary

In the first phase of the straw comprehensive utilization industrial park project in a certain city, the electromagnetic flowmeter relies onCorrosion resistant, anti blocking, precise, and highly adaptableThe characteristics of becoming a project flow measurement toolMain instrumentsIts application covers the entire process from process production to public engineering and environmental protection treatment. It not only provides key data support for the stable operation of the university's straw four element separation process, but also achieves multiple goals of "precise process control, effective energy consumption accounting, and environmental compliance guarantee". At the same time, the project is designed based on the characteristics of the media in different sectionsDifferentiated selectionand定制化配置This not only ensures measurement accuracy but also achieves cost control, providing support for the selection, installation, and operation of electromagnetic flow meters for the subsequent 300000 tons/year Phase II projectCan be copied and enlargedThe engineering experience has also provided reference for the application of process instruments in other high-value straw utilization projects in China.