Process Control
Desulfurization, CO₂ removal, compression, and purification sections are centrally presented in one SCADA view. Temperature, pressure, flow, and level refresh in real-time; trends and alarms are retained together — supporting long-term stable operation.
Biogas buffer and cooling/drying
Buffer tank stabilizes pressure; chiller removes free water
Biogas compression
Boost to the pressure required by downstream process steps
Pretreatment tower
Removes particulates and impurities
MDEA absorber
Amine solution absorbs CO₂; purified gas exits from tower top
Solution regeneration tower
Heated desorption of acid gas; lean amine recirculated
TSA adsorption tower
Three towers switch — temperature-swing adsorption drying/fine removal
Grouped online monitoring
CH₄ / CO₂ / O₂ / H₂S and calorific value
CNG four-stage compression
four-stage compression with inter-stage cooling and separation
What Process Control does
Process Overview
SCADA views drawn from actual P&IDs — equipment status and real-time parameters at a glance.
Parameter adjustment
Valve position, frequency, and setpoints remotely commanded within authorized ranges — all actions logged.
Alarms & interlocks
Limit-crossing triggers audible-visual alarms and safety interlocks — alarm logs are queryable, actionable, and archivable.
Multi-section coverage
Utilities, MDEA Skid, TSA Skid, Biogas Compressor, and CNG Compressor A/B are all included.
Stay in control of the plant even away from the control room
The same SCADA views adapt to mobile — duty and management staff can access section status, view alarms, and handle events anytime.
Alarm monitoring and logs in this system target process parameter limit-crossings and equipment faults — production control scope, independent from the Video Surveillance system.
From biogas inlet to grid injection — eight process sections
Each section has a corresponding SCADA view and real-time monitoring points — tag numbers map one-to-one with field equipment.
Biogas buffer and cooling/drying
Inlet biogas stabilized by buffer tank; chiller removes free water
Biogas compression
Boost to the pressure required by downstream processes, with oil temperature and heat dissipation interlocks
Pretreatment tower
Removes particulates and impurities, protecting downstream packing and membrane modules
MDEA absorber
Amine solution absorbs CO₂; purified gas exits from tower top
Solution regeneration tower
Heated desorption of acid gas; lean amine cooled and returned to absorber
TSA adsorption tower
Three towers switch — temperature-swing adsorption completes drying and fine removal
Grouped online monitoring
CH₄ / CO₂ / O₂ / H₂S and calorific value continuous detection
CNG four-stage compression
Four-stage compression with inter-stage cooling and separation — for loading or grid injection
What each section monitors
Below are monitoring items actually present in SCADA views — continuously acquired by the control system and used in alarm judgment.
Biogas Compressorgroup
Full monitoring of intake, exhaust, oil circuit, and motor status — abnormalities can trigger interlock shutdown.
- Discharge pressure · Suction pressure · Differential pressure
- Oil supply pressure · Oil supply temperature · Oil separator temperature
- Phase A/B/C winding temperature · Shaft-end temperature
- Host current · Host frequency · Unit load position
- Inlet level · Outlet level · Tank temperature
MDEA CO₂ removal skid
Lean/rich amine circulation and regeneration system: temperature, level, flow closed loop.
- Biogas flow and cumulative total · Purified gas pressure
- Absorber / regeneration tower level and temperature
- Lean/rich amine heat exchanger inlet/outlet temperature
- Acid gas flow and acid gas separator level
- Amine solution control valve · Purified gas control valve position
TSA drying/fine removal skid
Three towers switch by timing sequence — adsorption-regeneration-cooling cycles.
- T1 / T2 / T3 three-stage timing setup
- Current step and running time in current step
- Adsorption tower inlet/outlet pressure and temperature
- Regeneration gas heating and cooling temperature
- Temperature alarm/interlock setpoints (tunable)
CNG Compressor A/B
Four-stage compression with four-stage cooling and separation, including sound-enclosure environmental monitoring.
- Discharge pressure and temperature per stage
- Cooling water pressure · Oil supply pressure and temperature
- VFD adjustment and feedback · Operating current
- Tanker docking signal · On-site start/stop and emergency stop
- Sound enclosure temperature · Ventilation fan and space heater
Utilities
Centralized utilities management for steam, demineralized water, nitrogen, cooling water, and wastewater.
- Steam desuperheating/depressurization and condensate recovery
- Demineralized water and low-pressure nitrogen supply
- Cooling water pump and cooling tower fan
- Wastewater collection tank level and pump
- Solution storage tank level and lean amine pump
Alarms & interlocks
Limit-crossing triggers audible-visual alarms; severe conditions directly trigger interlock protection.
- Upper/lower alarms, tunable thresholds
- Alarms pushed to mobile in real time
- Alarm logs archived — supports handling and root-cause
- Multi-layer interlock: oil temperature / heat dissipation / ambient temperature
- Alarm handling records exportable
A set of actual values from the SCADA view
Below are real-time readings at screenshot time — illustrating monitoring granularity, not representing design conditions.
TSA three towers auto-switch by preset timing sequence
TSA Skid uses three parallel columns operating in adsorption–regeneration–cooling cycles; timing parameters are tunable within authorized ranges.
| Timing sequence stage | setpoint | Function | Related interlocks |
|---|---|---|---|
| T1 | 420 min | Adsorption stage — purified gas flows upward through the adsorption tower | TT4105 < 110 ℃ |
| T2 | 200 min | Regeneration stage — regeneration gas heated and reverse-purged | TT4102 > 55 ℃ |
| T3 | 360 min | Cooling section — regeneration gas cooler brings gas to standby | TT4107 > 45 ℃ |
Actual system UI
Below are original screenshots of the system backend and mobile app — click to enlarge and view.
