Why Raw Materials Must Be Identified Before Building a Brick Plant

Raw materials are the fundamental prerequisite for all process, equipment, and kiln design in a sintered brick and tile plant. A brick plant cannot first select equipment, build workshops, and then look for raw materials; the raw materials must first be tested and analyzed, and only then can the overall design proceed. The mineral composition, plasticity, drying sensitivity, calorific value, and hardness of the raw materials determine the crushing equipment, aging storehouse selection, drying chamber, kiln, setting/firing process, and product range, directly affecting project investment, post‑commissioning yield, energy consumption, and profitability.

1. Determines the selection of crushing and preparation equipment

Different raw materials vary greatly in hardness: shale has high hardness and requires jaw crusher + hammer crusher; clay is relatively soft, and a roller crusher can be used; materials like fly ash and tailings require almost no coarse crushing.

Without knowing the hardness and particle size of the raw material, oversizing the crusher leads to wasted investment and high power consumption; undersizing results in insufficient output and failure to achieve the required grinding fineness, causing problems in subsequent forming. This also determines whether auxiliary equipment such as stone removal, iron removal, and screening are needed.

2. Determines the aging process and aging storehouse scheme

Depending on the plasticity index, the aging requirements differ completely. Highly plastic, drying‑sensitive materials require longer aging times, with preference for bridge‑type or semi‑bridge aging storehouses to ensure thorough homogenization and first‑in‑first‑out operation; low‑plasticity hard materials have shorter aging cycles and can use side‑type aging storehouses.

Raw material testing yields the required aging days, determining the storage capacity, stacking height, and sealing requirements. Without knowing the raw material, the aging storehouse design becomes arbitrary.

3. Determines the forming process and product positioning

The plasticity index directly determines whether the material is suitable for solid bricks or high‑porosity thin‑wall hollow bricks.

A plasticity of 7–15 is suitable for extrusion forming; below that, thin‑wall hollow bricks simply cannot be produced, and the green bodies are prone to cracking.

The raw material properties also determine whether a single‑stage setting/firing or two‑stage setting/firing process is used. Materials with high drying sensitivity cannot be forced into single‑stage setting/firing; otherwise, the green bodies will collapse and suffer extensive cracking and rejection.

4. Determines the drying chamber process design

The drying sensitivity coefficient, critical moisture content, and forming shrinkage rate are the core design basis for the drying chamber.

– High‑sensitivity materials: cannot be dried rapidly; the drying chamber must be lengthened, hot‑air velocity reduced, and temperature/humidity regimes moderated.
– Low‑sensitivity materials (e.g., some Turkish shale types): can use rapid drying, allowing shorter drying tunnel length and saving civil construction costs.

Without raw material testing, the drying chamber air volume, velocity, air supply position, and drying time are all estimated empirically, making large‑scale drying cracks highly likely after commissioning.

5. Determines the firing kiln design and fuel consumption

- Chemical composition determines the firing temperature: high alumina content requires raising the firing temperature, which in turn alters refractory selection and kiln insulation structure.
- Harmful impurities such as limestone and sulfates in the raw material must be identified in advance to avoid quality defects like lime bursting and efflorescence.

6. Determines project investment, operating costs, and risk assessment

– Poor raw materials require additional investment in crushing, screening, batching, and aging equipment.
– Good raw materials allow simplified equipment configuration.
– Early raw material testing can reveal in advance whether the material can actually be used for brickmaking and whether the target product can be produced, thus preventing huge investment losses from building workshops and purchasing equipment only to find the raw material unsuitable.

7. Determines long‑term stability of production operations

Identifying the raw material and establishing the batching formula before construction ensures stable operating parameters for subsequent production. If the raw material is unclear, after commissioning problems will arise: insufficient plasticity one moment, drying cracks the next, high rejection rates during firing, repeated production adjustments, low yield, and persistently high energy consumption.

News Editor: Wendy Luo
Source: Han Lu, Engineer, Brictec Technical Department
Reviewer: Wei Jiangfei
Publisher: Xi'an Brictec Engineering Co., Ltd.
Release Date: September 9, 2026