Medium Temperature Anaerobic Solution: Process, Tankage, And Biogas
A medium temperature anaerobic solution is a sealed, heated biological system that converts organic waste into biogas at 35-38 C. The reactor, usually a CSTR (Continuous Stirred-Tank Reactor), and its Glass-Fused-to-Steel tankage must be engineered as one system, because the vessel wall, the mixing, and the gas seal all define how much methane is actually recovered.
What Mesophilic Anaerobic Does
In the absence of oxygen, hydrolytic and methanogenic microbes break volatile solids into biogas. The gas is roughly 55-65% methane, with the rest mostly carbon dioxide. At 35-38 C the mesophilic community converts about 0.30-0.45 m3 of biogas per kg of COD removed, and the process produces far less sludge than aerobic treatment.
| Parameter | Typical Value | Why It Matters |
| Methane content | 55-65% of biogas | Sets fuel value |
| Biogas yield | 0.30-0.45 m3 / kg COD removed | Sets digester size |
| Mesophilic temperature | 35-38 C | Stable microbiology |
| Retention time | 20-40 days (CSTR) | Sets reactor volume |
Choosing The Reactor
A CSTR is mixed and heated, which suits uniform manure or food slurry. A UASB needs low solids and warm, soluble feed, and it runs at a high organic loading rate (5-15 kg COD/m3/day) with hours of retention rather than days. The choice is driven by solids and temperature, not by brand.
A Boundary Condition
Medium temperature anaerobic is not suited to cold, low-strength sewage or to feed with heavy suspended solids unless those are removed upstream. A UASB will wash its granular bed out if solids or temperature drift; a CSTR will underperform if the feed is too dilute to sustain the biology. Co-digestion can steady the carbon-to-nitrogen ratio toward 20-30:1.
Project Case Study: Zhenyuan Group Biogas Project In Henan
Project / Application: Vehicle-grade methane production from farm manure and washing wastewater, Xinzheng, Henan, China. Industry: Biogas and renewable energy. Tank Type: CSTR (Continuous Stirred-Tank Reactor). Key Requirements: Reliable medium-temperature methane for vehicle fuel.
| Field | Value | Source / Evidence |
| Handling Capacity | 650 T/D (manure + washing wastewater) | Company project reference |
| Treatment Type | Medium Temperature Anaerobic Fermentation | Company project reference |
| Reactor Type | CSTR (Continuous Stirred-Tank Reactor) | Company project reference |
| Primary Reactors | 3 sets, O15.29 x 15 m | Company project reference |
| Secondary Reactor | 1 set, O5.22 x 6 m | Company project reference |
| Annual Methane Production | 3,000,000 m3 (vehicle-grade) | Company project reference |
| Installation Year | 2013 | Company project reference |
About The Supplier
Shijiazhuang Zhengzhong Technology Co., Ltd (Center Enamel) manufactures Glass-Fused-to-Steel tanks rated for medium temperature anaerobic digestion of livestock and food waste, with enamel firing at 820-930 C and certifications including ISO 9001, NSF/ANSI 61, and CE-EN 1090. The bolted CSTR packages support rapid deployment for biogas projects.
Comparison: Reactor Choices For Mesophilic AD
| Reactor | Best Feed | Note |
| CSTR | Uniform manure or food slurry | Mixed and heated |
| UASB | Low-solid warm effluent | High loading, low energy |
| USR | Coarse high-solid feed | Holds solids without fine mixing |
A medium temperature anaerobic solution is a biology problem wrapped in a tank problem. Choose the reactor from the solids and temperature, engineer the vessel and the mixing as one, and the biogas recovery becomes a measured output rather than a hope.
Frequently Asked Questions
Q1: What is a medium temperature anaerobic solution? A1: A sealed, heated biological system that converts organic waste into biogas at 35-38 C.
Q2: Why run at 35-38 C? A2: Mesophilic microbes are stable and productive in that band, with lower heating cost than thermophilic.
Q3: Which reactor suits mesophilic AD? A3: A CSTR for uniform slurry, a UASB for low-solid warm effluent, a USR for coarse feed.
Q4: How is biogas guaranteed? A4: Through a single loading-rate and retention-time basis owned by one responsible party.
Q5: What is the methane content? A5: Mature feed typically yields 55-65% methane in the biogas.
Q6: What tank resists the corrosion? A6: A Glass-Fused-to-Steel tank with a factory-fired enamel lining.
Q7: How is the gas used? A7: It can be burned for heat and power, or upgraded to biomethane for vehicles.
Q8: Can the system expand? A8: Yes, modular GFS panels add digester volume as feedstock grows.
Describe your organic feedstock and off-take goal to an engineer, or request a medium temperature anaerobic solution scope.