Separation of cellulose from industrial paper mill wastewater dried sludge using a commercial and cheap ionic liquid.

Industrial wastewaters and their treatment are now placed at the heart of the environmental concerns that industries face. Some research work has been carried out in order to limit the impact of these wastes on the environment as well as their costs. In this study, wastewater dehydrated sludge (55% wt. water content) from the paper industry was used to recover cellulose by using tetrakis(hydroxymethyl)phosphonium chloride, [P(CH2OH)4]Cl, ionic liquid as a solvent. The ionic liquid has shown remarkable results in terms of cellulose extraction in addition to its non-volatility and lower toxicity compared to organic volatile solvents. All cellulose, based on dry sludge, was recovered from the industrial dehydrated sludge with better operation conditions. The influence of temperature and the quantity of ionic liquid was preliminary studied in order to optimise the extraction conditions.

Effect of temperature on hydrothermal liquefaction of high lipids and carbohydrates content municipal primary sludge.

The study assessed the valorisation of primary sludge through HTL and the influence of temperature on the product distribution. The experiments were conducted at different temperatures, 30 min reaction time, and 100 rpm stirring rate. The maximum yield of biocrude produced was 39.47% at 270 °C. The best yield of oils was 23.96% at 300 °C. The lowest yield of asphaltenes was 12.50% at 240 °C. HHV for biocrude were always between 39 and 41 MJ/kg, close to petroleum. Best energy recovery for biocrude was 82% at 270 °C.