Calculator Inputs
Example Data Table
| Scenario | Daily solids (kg/day) | Solids in slurry (%) | Retention (days) | Water added (L/day) | Working fill | Safety (%) |
|---|---|---|---|---|---|---|
| Small garden system | 6 | 8 | 7 | 80 | 0.85 | 10 |
| Medium greenhouse loop | 12 | 8 | 10 | 150 | 0.85 | 15 |
| High-load organic slurry | 25 | 6 | 14 | 250 | 0.80 | 20 |
Formula Used
- Solids fraction: f = (slurry_solids_pct / 100)
- Slurry mass per day: M = daily_solids_kg / f
- Slurry volume per day: Qs = M / density
- Water volume per day: Qw = water_add_lpd / 1000
- Base working volume: Vbase = (Qs + Qw) × retention_days
- Working volume with safety: Vwork = Vbase × (1 + safety_pct/100)
- Total tank volume: Vtank = Vwork / working_fill_frac
- Cylinder sizing: Vtank = (π/4) × (H/D) × D³, then H = (H/D) × D
- Total aeration: Air = aer_lpm_m3 × Vwork
- Mixing power: P(kW) = (mix_w_m3 × Vwork) / 1000
How to Use This Calculator
- Measure average daily solids sent to mineralization.
- Select a slurry solids percentage that you can mix.
- Choose retention time based on odor and breakdown goals.
- Enter expected make-up water that remains in the tank.
- Set a working fill fraction for headspace and foam control.
- Add a safety factor for seasonal and operational variation.
- Click Calculate to view results above the form.
- Download CSV or PDF to store project documentation.
Mineralization role in garden nutrient loops
Mineralization tanks turn trapped organic solids into dissolved nutrients that plants can absorb. Controlled aeration keeps the process aerobic, limiting odors and stabilizing water quality. The goal is not complete digestion, but predictable conversion that reduces oxygen demand and improves clarity in beds, reservoirs, and recirculating systems.
Sizing with solids loading and retention time
Tank sizing starts with daily solids mass, then estimates slurry flow using the chosen slurry solids percentage and density. The calculator adds any make‑up water that remains in the tank, then multiplies total daily inflow by the target retention time. A safety factor increases working volume to cover peak feeding, maintenance downtime, and seasonal swings. This approach supports consistent performance under normal variability for long-term reliability.
Managing slurry concentration and headspace
Higher slurry solids reduce water use, but can increase settling, clogging risk, and mixing effort. Moderate concentrations usually provide the best balance of pumpability and stability for small and medium gardens. Working fill fraction reserves headspace for foam, gas release, and turbulence, helping prevent overflow and improving circulation near the surface.
Aeration and mixing planning outputs
Aeration provides oxygen for microbes and helps suspend particles. The airflow estimate uses liters per minute per cubic meter of working volume, which is useful for sizing blowers and diffuser manifolds. Mixing power is a comparative planning value that can guide choices between mechanical mixers, recirculation pumps, or air‑lift circulation, depending on energy and noise limits. In practice, verify mixing with visual checks for dead zones and settling cones.
Turning results into a buildable tank choice
Use total tank volume to select a standard vessel size and verify that footprint, access, and cleaning points are realistic. The cylinder diameter and height help confirm stability and installation clearance. Recheck that effective retention meets your odor and stability targets, then select materials resistant to abrasion and organic acids, with drains for periodic sludge removal. Plan safe venting and splash control around diffusers and inspection hatches.
FAQs
1) What retention time is typical for mineralization?
Many systems start around 7–14 days. Higher solids, cooler temperatures, or strict odor control often benefit from longer retention.
2) Why does slurry solids percentage matter?
It affects slurry volume, mixing effort, and settling risk. Lower percentages are easier to circulate, while higher percentages reduce water but may clog equipment.
3) How should I choose the working fill fraction?
Select a level that leaves headspace for foam and turbulence. Values near 0.80–0.90 are common when aeration is active and overflow protection exists.
4) Is aeration always required?
Aeration is strongly recommended for stable operation. It helps prevent anaerobic odors and keeps solids suspended, improving mineral release consistency.
5) What safety factor should I use?
A 10–25% safety factor is common for variable feeding and occasional downtime. Increase it if solids loads spike or cleaning intervals are long.
6) Can I use multiple smaller tanks instead of one?
Yes. Multiple tanks can improve redundancy and allow staged cleaning. Keep total working volume equivalent, and ensure each tank has adequate aeration and mixing.