2026-11-12
Start with how the manure is collected
Pig manure is wet, and the collection system decides the process. Farms that scrape manure dry and keep rainwater separate from wastewater have the lowest processing cost. Farms that flush or soak manure in water need to separate liquids from solids first.
A screw-press separator splits slurry into a liquid fraction and a solid fraction at 40–60% moisture. Renyuan recommends building a settling pit of about 30 m³ ahead of the separator. Thinner slurry overflows from the top while thicker material settles at the bottom, which raises separator output considerably.
Three composting methods
| Method | How it works | Typical dimensions |
|---|---|---|
| Trough composting | Material composts in walled troughs while a trough turner mixes and aerates it. The most common method for commercial pig manure fertilizer; about 15 days to full maturity. | Width 3–20 m, depth 0.8–1.5 m, length 50–100 m |
| Enclosed tank | Manure at up to 80% moisture is conveyed into the tank and composted at high temperature with aeration, coming out at about 30% moisture with no odour release. | Chamber 32–116 m³ (Renyuan range) |
| Windrow composting | Material is laid out in long piles in the open or under a roof, and a turner keeps the piles aerobic. | Windrows 2–3 m wide and 1–1.5 m high |
Composting controls that decide success
- Particle size: manure and bulking material should be under 10 mm; crush anything larger.
- Moisture: adjust the mix to about 55–60%. Above 65% the trough has a high chance of failing to start.
- Bulking material: crushed rice straw, corn stalks, peanut stems or fallen leaves with a carbon-to-nitrogen ratio of 20–80:1. A manure-to-bulking ratio of about 3:1 is typical.
- Heating: after the first turn, expect 3–4 days to heat up (5–7 days in winter). Once the pile holds above 60–70 °C for more than 24 hours, turn it.
- Cycle: about 15 days in summer and 25 days in winter.
- Failed start: if the trough is still below 40 °C after 10 days, measure moisture. Above 60%, add bulking material and inoculant; below 60%, the inoculant dose was probably too low.
Granulation process
- Crush the composted and cured material.
- Add nitrogen, phosphorus, potassium and trace elements according to the formula, then mix.
- Granulate.
- Dry, then cool the granules.
- Screen. On-size granules can be coated before packing; oversize returns to the crusher and back to granulation.
- Weigh and bag automatically.
Configuration levels
Renyuan configures pig manure lines at four levels. You can start with a basic line and add equipment later.
| Level | Equipment |
|---|---|
| High | Continuous trough turner, automatic feeding hopper, screen, semi-wet crusher, horizontal mixer, granulator, dryer, cooler, grading screen, coating machine, automatic packer, belt conveyors |
| Standard | Manure dewatering machine, compost turner, semi-wet crusher, horizontal mixer, granulator, dryer, cooler, trommel screen, coating machine, packer, belt conveyors |
| Medium | Semi-wet crusher, horizontal mixer, granulator, dryer, cooler, trommel screen, packer, belt conveyors |
| Basic | Semi-wet crusher, horizontal mixer, granulator or trommel screen, packer, belt conveyors |
What to send us for a configuration
- Herd size and manure collection method (dry scraping or flushing)
- Moisture of the manure or separated solids
- Available bulking materials
- Target product: powder, granules or formulated fertilizer
- Planned annual output and site layout
Renyuan equipment for this line
- RY-ZFP Standard Trough Compost Turner
The standard RY-ZFP series turns and mixes organic material in fixed composting troughs. The 40/50 and A/B combinations have different widths, working depths and main motor ratings, so selection begins with the trough geometry.
- RY-ZFP Hydraulic Trough Compost Turner
A hydraulic-drive trough turner listed with four RY-ZFP models and model-specific dimensions and motor data.
- RY-LFD Series Crawler Compost Turner
RY-LFD crawler turners mix and aerate composting windrows across several working widths. Start with windrow width, then check site access and the turning requirements of the selected model.
- Intelligent Aerobic Fermentation Tank
The aerobic fermentation tank combines a chamber, lifting feed system, aeration, hydraulics and biological odor treatment for manure and other organic materials. Compare chamber volume and the stated treatment quantity separately across the four sizes.
- RY-FS60 Vertical Crusher
A vertical crusher for reducing fermented organic material before screening or further processing.
- Automatic Organic Fertilizer Batching System
The batching system coordinates recipe-based feeding of production materials and functional additives, with anti-bridging devices in the associated hoppers. Select hopper count, weighing and monitoring functions around the recipe and production schedule.
- Disc Granulator
Forms fertilizer granules in a rotating disc and connects with mixing and downstream finishing stages.
- Rotary Drum Dryer
A rotary dryer for fertilizer materials, arranged with a heat source and dust-collection equipment as required.
Frequently asked questions
What moisture should pig manure be at for composting?
About 55–60%. Above 65% the trough is likely to fail to start.
How long does pig manure take to compost in a trough?
About 15 days in summer and 25 days in winter, after a heating-up period of 3–4 days (5–7 days in winter).
What if the trough does not heat up?
If it is still below 40 °C after 10 days, check moisture. Above 60%, add bulking material and inoculant; below 60%, add more inoculant.