The phenomenon of sludge flotation occurs in the secondary clarifier when activated sludge undergoes denitrification, causing the formation of sludge clusters that float to the surface or sludge particles that float and overflow with the effluent. On the other hand, sludge bulking is caused by poor settling performance of activated sludge. When the sludge-water mixture…
I. Introduction to Mixed Liquor Suspended Solids (MLSS)Mixed Liquor Suspended Solids (MLSS), also referred to as mixed liquor suspended solid concentration, represents the concentration of activated sludge in the mixed liquor. It indicates the total mass of solid particles in the activated sludge per unit volume of the mixed liquor. The units of measurement are…
During the operation of a wastewater treatment plant, staff members often observe a substantial amount of garbage in the bio-tank, secondary settling tank, and other areas. This not only affects the aesthetics but also significantly impacts the equipment operation, such as water pump blockage, abnormal mixer sounds, sludge suction machine blockage, among others. So, what…
Sludge is the byproduct separated from urban sewage treatment, which has a water content of over 85% in a liquid state, 65% to 85% in a plastic state, and below 60% in a solid state. Classification of Sludge Sludge can be classified based on the source, digestion, and composition. According to the source, it can…
When a sewage treatment facility is put into formal use, its biochemical treatment equipment needs to be inoculated and acclimatized (commonly known as commissioning). For larger-scale sewage treatment facilities, it is important to shorten the commissioning time as much as possible, so that the treatment process can be put into normal operation as soon as…
Activated sludge aging is common in most aerobic biochemical systems, and the aging of activated sludge leads not only to an increase in the major pollution indicators of the effluent, but also to a waste of energy. Due to the aging of activated sludge, excessive aeration and low loads tend to cause excessive energy consumption….
Multi-disc sludge dewatering machine, referred to as screw stacking machine, is a water treatment system widely used in municipal sewage treatment projects and petrochemical, light industry, chemical fiber, papermaking, pharmaceutical, leather and other industrial industries. Filtration equipment first appeared during the European Industrial Revolution in the 19th century. The earliest industrial filtration equipment that came out…
In fact, filter presses produce excellent cake dryness and, in many cases, higher cake dryness compared to other filtration equipment. What is “silt”?Simply put, “sludge” is a semi-solid slurry that can be produced from a variety of industrial and municipal processes.The purpose of sludge dewatering is to reliably and efficiently concentrate waste into a filter…
Biosolids are the concentrated, stabilised solids product generated from the treatment of sewage sludge. During wastewater treatment, the liquids are separated from the solids. Those solids are then treated physically and chemically to produce a semisolid, nutrient-rich product known as ‘biosolids’. The terms ‘biosolids’ and ‘sewage sludge’ are often used interchangeably. However, biosolids are usually considered to…
Sedimentation and filtration Two key aspects of sludge solid−liquid separation processes for which fundamental theoretical representations exist are gravitation (or ‘sedimentation’) and filtration. These expressions can be used to inform the extent of separation of solids from the liquid and/or the energy required for certain thickening or dewatering processes. Sedimentation is the separation of particles…