Recycling Possibilities of Sewage Sludge from Water Purification

Abstract

The sewage sludge from a water purification plant was analysed for recycling to the dense glass-ceramic materials. The sewage sludge containing aluminium compounds and circa 50 % of organic matter was used as a filler, but as the matrix of glass-ceramic was examined an illitic clay from Liepa deposit (Latvia). The raw materials were investigated by differential-thermal (DTA) and X-ray diffraction analysis (XRD). The dense glass-ceramic was produced from the water purification sewage sludge and limeless clay in ratio 10-40 : 90-60. The optimal values of bulk density (2.28 g/cm 3 ) and thermal shrinkage (29 %) for novel materials were observed for glass-ceramic with the sludge additive at amount of 20 wt %, obtained by sintering at temperature 1140 °C. The relationship between thermal treatment conditions and maximal treatment temperature was established. The following crystalline phases for novel materials were detected by XRD analysis: microcline (KAlSi 3 O 8 ), hematite (Fe 2 O 3 ), quartz (SiO 2 ) and corundum (Al 2 O 3 ). The physical-chemical properties of novel materials correspond to the dense glass-ceramics composite while the material itself could be applied as building material.

Elemental distribution of latex‐based aerobic granules and its effects on micromorphological properties and settling performance

“…Moreover, silicon may be present as silicon dioxide (SiO 2 ) or quartz. For domestic sludge granules, the common minerals found are quartz and microcline apart from hematite, corundum, ilite, kaolinite, and gibbsite (Rozenstrauha et al., 2012).…”

“…Rozenstrauha et al. (2012) discovered hematite, quartz, corundum, and microcline. In addition, several studies also have determined that functional groups of saturated and unsaturated aliphatic and acyclic hydrocarbons, aldehydes and ketones, acids and esters as well as alcohols existed in sewage sludge (Bahrodin et al., 2021; Ratnasari, Syafiuddin, Boopathy, et al., 2022; Ratnasari et al., 2021; Syafiuddin & Boopathy, 2021b; Syafiuddin et al., 2021).…”

“…Although evaluating the performance of the wastewater treatment during biogranulation process is interesting, it is additionally important to investigate the chemical properties of developed AGS from a particular types of wastewater treatment in SBR to understand their attributes, which deliver their settling performance. A study was performed to determine the chemical characteristics of aerobic granules mainly for evaluating the possibilities of reusing aerobic granules for further significant treatment and the recovery of valuable compounds (Rozenstrauha et al., 2012). One of the important elements determined that were able to assist granulation process is the presence of metal cations as it neutralizes the negative charges on the bacterial cell surfaces which quickens the formation of aggregates.…”

Development of an energy- and water-saving manufacturing technology of brick products

“…For the synthesis of porous ceramics, a number of pore-forming agents from inorganic (e.g., limestone, dust, CaCO 3 , and CaMg (CO 3 ) 2 ) [24,25], and organic origin (milled coal, rubber, wood sawdust, rubber, different types of sludge, polystyrene, brewery waste, recycled paper processing residues, etc.) [23,[26][27][28][29][30][31][32] are added to clay. Thus, even the presented brief list of works on the manufacture of bricks with different additives indicates that the range of introduced additives can be substantially extended.…”