Fine bubble disc diffusers are specialized aeration devices used primarily in water treatment applications, such as in wastewater treatment plants and aquaculture systems. These disc diffusers are designed to release small, fine bubbles into water or liquid for the purpose of oxygen transfer and efficient mixing. Constructed from materials like EPDM (ethylene propylene diene monomer) or silicone, these disc-shaped diffusers have micro-perforations across their surface. These micro-perforations, or tiny holes, allow for the controlled release of air in the form of fine bubbles. These bubbles are significantly smaller in size compared to coarse bubble diffusers, and their small size ensures a longer residence time in the water, maximizing the surface area for oxygen transfer.

Coarse bubble diffusers are a type of aeration device used in water treatment processes, particularly in wastewater treatment plants. They're designed to introduce large bubbles into water or liquid, aiding in the transfer of oxygen and mixing within the water body. These diffusers typically consist of larger apertures or openings through which air is released into the water. The bubbles produced are comparatively larger in size compared to fine bubble diffusers, which allows for more rapid ascent through the water column. This ascent facilitates mixing and helps in the aeration process by bringing oxygen from the air into contact with the water.

A filter press is a solid-liquid separation device used to dewater sludge, separate solids from liquids, and filter materials in various industries, including wastewater treatment, chemical, pharmaceutical, and food processing. The primary purpose of a filter press is to efficiently remove liquid from a mixture and produce a dry cake material. The device comprises a series of filter plates with recessed chambers and a filter cloth or other filter media between each plate. The plates are typically made from materials such as polypropylene, stainless steel, or cast iron. The filter plates are assembled together, forming a stack with an opening in the centre for the feed to enter the chambers.