Mixed Animal Waste and Straw Fertilizer Production Line: Complete Turnkey Solution for Diversified Farms

Project Overview

Mixed Agriculture Operations — a diversified livestock and crop farm based in Southeast Asia commissioned a turnkey mixed animal waste and straw granulation plant to process combined chicken litter, pig manure and rice straw into uniform organic fertilizer pellets. The line was designed for an initial capacity of 3–5 tons per hour. Shenghong Heavy Industry supplied the complete production line including pre-treatment dewatering, formulation mixing, deep fermentation, disc pan granulation, drying, cooling, screening, coating and automatic packing.

Key Challenges

The client faced three core issues:

• Heterogeneous raw materials — combining chicken litter (high nitrogen), pig manure (high moisture) and rice straw (high fiber) required careful moisture balancing and ratio adjustment.
• Nitrogen loss control — fermented chicken litter can lose up to 40% nitrogen during aerobic composting if not managed properly.
• Labor-intensive traditional method — previously relied on manual turning and open-air composting, causing odor complaints from neighbors.

Complete Plant Process Flow

The Shenghong turnkey line comprises the following stages:

1. Pre-treatment: Chicken litter is separated by screw press (typically SHLX180 or SHLX280) to reduce moisture. Rice straw crushed separately. Pig manure collected via slurry system.
2. Ratio-based batching: Three-stream material feeding via B500 belt conveyors feeds into a multi-material auto-batching system (B650) for precise ratio control—maintaining C/N ratio at 25-30:1 and moisture at 40-45%.
3. Formulation mixing: Batched material enters a SH900x1500 spiral ribbon mixer where commercial microbes and mineral supplements are evenly distributed.
4. Deep fermentation: Mixed material transferred to an in-vessel fermentation tank for controlled temperature 60-70°C over 7-10 days. Forced aeration ensures oxygen availability while minimizing ammonia volatilization.
5. Disc pan granulation: Fermented material enters the Disc Pan Granulator (ZL series). Unlike drum granulators which work best with pure organics, the disc pan method excels at forming round balls from moderately moist mixtures. Powder rises along the rotating arc disc while water spray is added; particles adhere into seed cores, grow layer-by-layer into round balls, and overflow at the disc edge.
6. Rotary drying: Wet granules (moisture ~30%) pass through a SHG8800 rotary dryer, reducing moisture below 15%.
7. Rotary cooling: Hot dried granules cooled to ambient temperature.
8. Sieving: Oversize granules crushed and returned; undersize fines recycled back to disc granulator inlet via 1.0x3.0 rotary screener.
9. Coating and packing: Nutrient film applied in 1000x3000 drum coater, then bagged by BLD-K50/S packer.

Main Equipment Configuration

Why Disc Pan Granulation for Mixed Waste?

For heterogeneous mixed animal waste + straw feedstock, the Disc Pan Granulator offers advantages:

• Tunable rolling path — disc angle adjustable 35-55° allows fine-tuning for different raw material combinations and target granule sizes.
• Binder-free granulation — natural binding properties of fermented chicken litter plus starch from straw create strong inter-particle adhesion without synthetic binders.
• Versatile sizing — produces uniform spherical pellets ideal for mechanized field application.
• Lower capital cost — simpler structure compared to drum granulators, making it attractive for mid-scale operations.
• Easy operation — minimal maintenance requirements with flexible belt drive and hardened main gear.

Plant Specification Snapshot

About This Solution

Every Shenghong production line is engineered to the client's raw material, site layout and budget. Whether you work with mixed livestock waste, crop residues, food processing by-products or industrial organic waste, our engineering team will design a customized line from pre-treatment through packing.