RSREX / MTRGEX Explosion‑Proof China Roots Blower | VOC Waste‑Gas Recovery | SHANGU MingTian

Close-up of ShanGu MingTian 2205 stainless steel petrochemical roots blower, display double oil tank isolation structure, chemical grade mechanical seal and direct coupling motor
Close-up shot of core structure of anti-corrosion roots blower, clearly showing independent double oil tank lubrication system, corrosion resistant mechanical seal and direct drive motor assembly. All overcurrent parts adopt 2205 duplex stainless steel to solve corrosion and gas leakage pain points of petrochemical hazardous gas delivery.

SHANGU® RSREX / MTRGEX Explosion-Proof Roots Blowers for VOC Waste-Gas Recovery & Abatement

Product Overview

For chemical plants, printing, coating, petrochemical tank farm and pharmaceutical industry VOC volatile-organic-compound waste-gas projects, explosion-proof roots blowers serve as core process equipment for waste-gas collection, pressurized conveying, oil-vapor recovery, gas recirculation for RTO / CO / zeolite-rotor systems.

SHANGU® RSREX, MTRGEX explosion-proof tri-lobe roots blowers are purpose-built by Shandong Mingtian Machinery Group, Made-in-China with US-Japan reference-grade technology for hazardous VOC service with flammable solvent vapour, trace corrosive components and condensate risk. As positive-displacement equipment, they deliver stable volumetric airflow under fluctuating pipeline resistance and variable VOC concentration.

Suitable for common organic waste-gas, oil-vapor, condensable solvent steam and low-corrosive process exhaust. Widely deployed in chemical parks, printing & packaging, automotive coating, petrochemical tank-farm oil-vapor recovery, pharmaceutical synthesis waste-gas treatment, rubber-plastic industry exhaust abatement. Material options include standard HT250 cast-iron housing & rotors, heavy-duty epoxy coating, optional 304 / 316 L stainless-steel rotors and casings for corrosive VOC-containing exhaust.

Rare Practical Field Tips (Seldom Published Online)

  1. All catalogue nominal data are under standard suction condition (20 ℃, 101.3 kPa, RH 65 %) clean-air basis. VOC waste-gas has different molecular-weight & density compared with air. Never select model directly by air-based catalogue values; correction for gas molecular-weight, inlet temperature and altitude must be completed. Add an 8-12 % flow margin for every 1000 m elevation rise. Mass-flow capacity drops sharply when inlet temperature exceeds 45 ℃.
  2. Critical selection pitfall for VOC project: explosion-proof motor alone cannot guarantee full-unit intrinsic safety. Anti-static rotor, flame-arrestor protection, multi-stage sealing, nitrogen-purge interlock and vent pipeline shall be equipped as a full package. Static-discharge ignition risk still exists if only motor is changed.
  3. Strictly distinguish Normal-state flow Nm³/min (0 ℃ for environmental-assessment report) vs actual working-condition flow Qs m³/min (20 ℃ blower inlet). Most EIA reports adopt normal-state flow, while blower performance is measured under working condition. Wrong conversion leads to insufficient gas-collection and fugitive emission. Conversion formula: Qs=Qn×1.0732
  4. VOC solvent vapour condenses inside casing during cooling process. Ordinary single-labyrinth seals will be quickly eroded by condensate liquid. Double-end mechanical seal with isolating-purge-gas port is mandatory; simple labyrinth-type seal is not acceptable.
  5. Excessive margin should be avoided. If flow-pressure margin exceeds 30 %, unit runs far from high-efficiency zone with over 20 % extra power-consumption. Reasonable process margin for VOC projects: 10-15 %.
  6. Backflow risk for VOC system is higher than ordinary air service. Swing check-valve alone is insufficient. Vacuum-breaking valve, vent pipeline and nitrogen-purge interface shall be equipped for shutdown organic-vapor displacement, preventing combustible-vapor accumulation hazard.

Applicable Industry Standards

  • JB/T 8941.1-2014: Roots type blowers for general purpose — Part 1: Specification
  • JB/T 8941.2-2014: Roots type blowers for general purpose — Part 2: Performance test method
  • JB/T 13233-2017: Explosion-proof roots blowers (Chinese industry standard for combustible-gas service)
  • GB 3836 series: Chinese explosive-atmosphere standards, MOD (Modified Adoption) of IEC 60079, comparable with EU ATEX 2014/34/EU directive.
  • HJ/T 251-2006: Environmental-protection product technical requirement for roots blowers.
  • GB/T 2888-2008: Method of noise measurement for fans and roots blowers.
  • GB 28381-2026: Minimum allowable values of energy-efficiency and energy-efficiency grades for blowers.

Standard Equivalence Note

  1. JB/T 8941.1-2014 is MOD (Modified Adoption) of ISO 1217:2009 Displacement compressors — Acceptance tests, NOT identical adoption. Overseas ISO 1217 lab test-reports serve only for reference. Domestic Chinese VOC-abatement projects shall perform final acceptance complying with JB/T & JB/T 13233-2017 & GB 3836 standards.
  2. GB 3836 ≈ IEC 60079 ≈ EU ATEX directive: equivalent but not fully identical. Separate ATEX certification is mandatory for EU export; domestic GB 3836 test-reports cannot replace EU-ATEX certificates.

Unit-Conversion Reference (For Tender & Cross-border Comparison)

Pressure:
9.8 kPa = 0.1 kgf/cm² = 1000 mmH₂O = 1.422 psi

Flow:
1 m³/min = 60 m³/h = 35.71 CFM

Gas-state conversion: Working-condition suction-state flow Qₛ (20 ℃) = Qₙ (0 ℃) × 1.0732

Important VOC project remark: Clearly mark working-condition / normal-state flow, Gauge / Absolute pressure in inquiry documents. Provide gas molecular-weight, air-based conversion formula cannot be directly applied for organic-vapor media.

Key Buyer Concerns (Explicit Requirements & Hidden Field Pain-points)

✅ Explicit Requirements

  • Working-condition flow & pressure matching total pipeline resistance and RTO / zeolite-rotor system load;
  • Explosion-proof rating matching hazardous-zone classification (Ex d ⅡB T4 / Ex d ⅡC T4);
  • Noise & vibration comply with chemical-plant site environmental limits;
  • Initial-investment budget and motor-power requirement;
  • PLC-compatible, VFD-ready for fluctuating waste-gas volume & concentration.

✅ Hidden Pain-points (Safety & production-loss risk outweighs equipment price gap)

  • Condensate-solvent seal-erosion risk: Condensed solvent vapour destroys ordinary seals, leading to fugitive organic-gas leakage, triggering both environmental-violation and safety hazards. Double-mechanical-seal with isolating-purge-gas design is required.
  • Full-unit intrinsic-safety requirement: Explosion-proof motor is only single component. Anti-static rotor, flame-arrestor, nitrogen-purge port and vent-interlock shall be fully equipped. Single-part explosion-proof ≠ full-unit explosion-proof.
  • 24/7 continuous heavy-duty reliability: Chemical & petrochemical production runs non-stop all-year-round. Units ≥ 60 kPa(gauge) shall adopt water-cooling construction. Overheating, oil emulsification and unexpected shutdown will paralyze entire VOC-treatment system and cause direct waste-gas discharge violation.
  • Selection error caused by mixing normal-state / working-condition parameters: Many projects adopt Nm³/min data from environmental-assessment report without temperature & molecular-weight correction, resulting in insufficient actual blower output and poor waste-gas capture.
  • Total-lifecycle-cost thinking: Evaluate power consumption, special-spare-part cost, outage loss, environmental-penalty and safety-risk instead of focusing merely on procurement price. Low-cost simplified-configuration units bring severe hidden hazards.
  • Customization & after-sales support: VOC is high-risk medium. Manufacturer shall provide gas-property calculation, full-set explosion-proof-configuration advice, safety-oriented installation briefing and fast spare-part delivery for emergency breakdown.

Core Product Advantages | SHANGU® by Shandong Mingtian Machinery Group

Shandong Mingtian Machinery Group is national Hi-Tech Enterprise and national-level Specialized-Sophisticated “Little-Giant”. Made-in-China manufacturing adopting US-Japan reference-grade technology standards. Two industrial parks are equipped with 5-axis machining centers, high-speed dynamic-balancing testers and three-coordinate measuring instruments. The R&D team includes professor-level senior engineers, PhD and master specialists with university-industry-research cooperation. SHANGU® is a well-known trademark of Shandong Province.

  1. Constant-volume anti-back-pressure performance: Tri-lobe rotors pass G2.5-grade high-speed dynamic balancing. Stable working-condition airflow even under variable waste-gas load and pipeline resistance, guarantee high waste-gas-collection efficiency.
  2. Complete VOC-oriented explosion-proof & corrosion-resistant customized solutions:
    • Explosion-proof package: Exd ⅡBT4 / Exd ⅡCT4 explosion-proof motor, anti-static rotor; reserved ports for flame-arrestor, nitrogen-purge displacement and vent interlock pipeline.
    • Sealing solution: Double-end fluororubber mechanical-seal with isolating-purge-gas port, resisting erosion from condensed solvent liquid.
    • Corrosion-resistant option: Heavy-duty epoxy coating for ordinary VOC service; 304 / 316 L stainless-steel rotor & casing for medium containing H₂S or acidic solvent.
  3. Enhanced water-cooling for high-pressure duty: Units ≥ 60 kPa(gauge) equipped with circulating water-cooling system for non-stop 7 × 24-h full-load chemical-plant service.
  4. VOC-optimized full-scope package supply: Precision inlet filter, flame-arrestor assembly, inlet-outlet silencers, safety relief valve, swing check-valve, vent-valve unit, anti-vibration base, anti-static flexible expansion joints. Optional explosion-proof VFD cabinet automatically adjusts airflow following waste-gas-load change, delivering 18-30 % energy-saving.
  5. Full-scope factory acceptance test: Each unit undergoes performance, explosion-proof index, noise & vibration test complying with JB/T 8941, JB/T 13233-2017, GB 3836 series. Complete test-report documentation available for tender and export-EPC-project acceptance.
  6. Full-process-technical-service: Multi-dimensional condition-calculation including gas-molecular-weight, inlet-temperature and altitude; safety-oriented installation briefing; retrofitting for legacy VOC blowers; regular explosion-safety maintenance guidance.

Application Scenario & Model-Selection Reference

Selection tips: Reserve 10-15 % margin for flow-pressure parameters. Choose MTRGEX water-cooled explosion-proof series for pressure＞88.2 kPa. Confirm explosion-proof, sealing & purge-gas configuration for VOC organic-gas service. 1 operating + 1 standby configuration recommended for critical chemical-plant VOC-abatement systems. Perform condition correction for high-altitude & high-inlet-temperature; strictly distinguish working-condition vs normal-state flow.

Application Scenario Working-condition Description Recommended Model Working-condition Flow(m³/min) Gauge Pressure(kPa) Motor Power(kW) Remarks
Small-medium printing / coating-workshop VOC waste-gas collection Printing-packaging & small-coating line, intermittent duty, fluctuating VOC concentration, short-to-medium pipeline RSREX100 5-18 49-68.6 7.5-30 Full-unit explosion-proof, double-mechanical-seal; VFD optional; flame-arrestor connection port reserved
Pharmaceutical / rubber-plant medium-size chemical VOC treatment Pharmaceutical-synthesis & rubber-processing, trace solvent-condensate, continuous-run RSREX150A 18-35 58.8-88.2 30-75 Water-cooling recommended for pressure＞60 kPa; nitrogen-purge port as standard; upgrade stainless-steel for corrosive-components
Large-scale chemical-park, complete-set RTO / zeolite-rotor system Large-chemical-production-line, long-pipeline, 7×24-h non-stop service, complex multi-component waste-gas MTRGEX250 35-60 68.6-117.6 75-132 Mandatory water-cooling; full anti-static explosion-proof + double-mechanical-seal; 1-op-1-standby recommended
Petrochemical tank-farm oil-vapor recovery & large chemical tail-gas boosting Tank-farm oil-vapor recovery, long-distance high-load pipeline, oil-condensate-containing medium MTRGEX300 60-105 88.2-120 90-160 Heavy-duty water-cooled unit; customize material & sealing after medium-assay; site-survey & pipe-resistance calculation required
Auxiliary VOC service: waste-gas recirculation & adsorber desorption purging Large-flow low-pressure duty for RTO gas recirculation, activated-carbon-tank desorption air supply RSREX175A~RSREX200 15-48 29.4-58.8 22-90 Explosion-proof configuration, optimized for large-flow low-pressure circulating-gas supply

Model Explanation

  • RSREX Series: General-purpose explosion-proof tri-lobe roots blower (belt / coupling drive), for medium-low-pressure VOC waste-gas collection, intermittent & continuous-run duty.
  • MTRGEX Series: Mingtian heavy-duty water-cooled explosion-proof roots blower, engineered for high-pressure, long-distance, 24-h hazardous chemical-plant VOC service, with built-in cooling-water ports plus integrated sealing-purge connection ports.

Installation & Maintenance Guidelines (critical for hazardous VOC service, rarely published online)

  1. Never subject pipeline weight onto blower flanges. Install anti-static flexible expansion joints both on inlet & outlet to isolate pipe-stress and vibration transmission.
  2. For combustible VOC waste-gas: install flame-arrestor on suction side; equip nitrogen-purge port for organic-vapor displacement before maintenance; route vent-pipe to safe zone. Hot-work on blower casing is strictly forbidden.
  3. Install filter-elements in cooling-water circuit for regular descaling for water-cooled models.
  4. Perform shift-based inspection of working pressure, running current, bearing temperature and seal solvent-leakage; regularly carry out combustible-gas-leakage test; shorten inspection interval for seal & purge-gas supply system.
  5. Inspect rotor abrasion-corrosion and seal-ageing during annual shutdown maintenance; replace wearing-parts proactively to avoid medium-leakage-caused safety & environmental incidents.

Disclaimer: All tabulated parameters serve for general-reference only. For real-world projects, please provide waste-gas-component, gas molecular-weight, working-condition / normal-state flow, required gauge pressure, hazardous-zone classification, total-pipe-length & elbow-quantity, inlet-gas temperature and site altitude. Our technical engineers will deliver condition-corrected custom proposal.

Inquiry — Please provide below information for customized solution & formal quotation

Kindly send your project-parameters, our engineering-team will prepare tailor-made blower-solution and formal commercial quotation:

  1. Waste-gas medium composition & gas molecular-weight;
  2. Flow value: distinguish working-condition flow or normal-state flow (m³/min or CFM); required working gauge / absolute pressure(kPa / psi);
  3. Application type: VOC waste-gas collection, oil-vapor recovery, RTO recirculation, adsorber desorption or others;
  4. Hazardous-zone classification for explosion-proof-rating definition;
  5. Pipeline-data: total pipe-length, elbow-quantity;
  6. Operation-mode: intermittent / 24-h continuous-running;
  7. Special-requirements: VFD, explosion-proof grade, stainless-steel upgrade, nitrogen-purge interface, standby-unit requirement;
  8. Power-supply-standard (voltage & frequency);
  9. Site-ambient-condition: altitude, average inlet-gas temperature;
  10. Any other site-specific safety & process-requirements.

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