How are stones broken into sand and stones? What is the equipment for processing stones?

The process of breaking stones into sand and smaller stones typically involves several stages, starting from the initial crushing of the raw stones down to the final shaping and grading of the particles. Here's an overview of the process and the equipment used:

1. **Primary Crushing**: The raw stones are first introduced to a jaw crusher, which is the most common equipment for primary crushing. The jaw crusher compresses the stones between a moving jaw and a fixed jaw, breaking them into smaller pieces.

2. **Secondary Crushing**: The output from the jaw crusher is then passed through a cone crusher or a impact crusher. These crushers further reduce the size of the stones by breaking them apart with a combination of compression and impact forces.

3. **Tertiary Crushing**: In some cases, a third crushing stage using a fine impact crusher or a cone crusher is necessary to achieve the desired particle size for sand production.

4. **Screening**: After crushing, the stones are screened to separate them into different sizes. This is done using vibrating screens, which sort the material based on particle size. The different sizes can be used for different applications, with the smaller sizes potentially being further processed into sand.

5. **Sand Production**: To convert the crushed stones into sand, a sand-making machine or a vertical shaft impact (VSI) crusher is often used. This equipment uses high-speed rotation and impacts to break down the stones into fine sand particles.

6. **Shaping and Gradening**: For stones that require specific shapes or gradations, additional equipment such as a cone crusher or a VSI crusher can be used. These crushers can provide more control over the final particle shape and size.

7. **Washing**: To remove impurities and dust, the sand may go through a washing process. This can be done using washing machines, which combine water and mechanical action to clean the sand.

8. **Drying**: Depending on the application and climate, the sand may need to be dried before being used. This can be done naturally or with the help of dryers.

The specific equipment used in each stage will depend on the desired final product, the hardness of the stones, and the capacity requirements of the operation. It's common for mining and quarrying companies to use a combination of these machines to achieve the desired output.

It's important to note that the process and equipment used can have environmental implications. Proper dust control, water management, and noise reduction measures should be implemented to minimize the impact on the environment and ensure the safety of workers.