PAPERmaking! g FROM THE PUBLISHERS OF PAPER TECHNOLOGY Volume 2, Number 1, 2016
sonicated using a Sonicator (SG-25) Roop Telesonic Ultrasonics Ltd. India with variable power intensity between 3 and 7.4W/cm2 and a frequency of 24kHz. The sample was immersed in ice and sonicated for total of 10 min with 1.5 min burst followed by 5 min rest in ice. Next added 1.3ml K2CO3 (pH 11.5) again sonicated for 2 min and added 1.5ml of acetic anhydride and sonicated for 2 min again added 0.5ml acetic anhydride further added 5ml of hexane and again sonicated and centrifuged and further extracted with hexane. After centrifugation at 10,000 rpm for 15 min, the supernatant was used to analyse the chlorophenols. The GC analysis were performed in electron capture detection mode with a gas chromatograph Nucon GC-5765 (Centurion Scientific, India) capillary column DB-5 (30 metre length 0.025mm i.d. 0.25 lm film thickness) was used at a temperature program of 50°C (2 min) then raised to 10°C/min to 280°C where it was held for 10 min. Helium was used as the carrier gas at a constant flow of 1.2ml/min. The samples were analysed in splitless mode at an injection temperature of 250°C and detector temperature 280°C. The Metals was determined as per (APHA 1995) first sludge sample was digested with nitric and perchloric acid (3:1) and filtered through Whatman no.42 paper. The filtrate was used for characterisation of phosphorus content and the trace elements were analysed on furnace atomic absorption spectroscopy (AAS) and rest were analysed on flame AAS. The hydride forming elements were analysed using hydride generator. Statistical analysis Data were statistically analysed by analysis of variance (ANOVA) and the mean differences were compared by Tukey – Kramer Multiple Comparison Test at p<0.05. All experiments were performed in three replicates and analyses were performed using GraphPad Prism (v 4.03) software. (CA, USA). Results and discussion Characterisations of sludge In recent time, interest for vermicomposting (using earthworms to breakdown organic materials) has increased (Hand 1988; Edwards 1988; Edwards and Bohlen 1996) due to its potential. In its basic form, this is a low-cost technology system that primarily uses earthworms in the processing or treatment of organic wastes (Hand 1988). Certain species of earthworm can consume organic material residuals very rapidly and fragment them into much finer particles and reducing the pollutants by passing them through a grinding gizzard. The earthworms derive their nourishment from microorganisms that grow upon these materials. At the same time, they promote further microbial activity since the faecal material or casts that they produce is much more fragmented and microbially active than what they consume (Edwards 1988; Edwards and Bohlen 1996). During this process, the important plant nutrients in the material (particularly the N, K, P and Ca) are released and converted through microbial action into forms that are much more soluble and available to plants than those in the parent compounds. Therefore, first, collected secondary sludge samples were characterised for various physical and chemical characteristics such as pH, organic matter, CHNS, AOX, and EOX described in (Table 1). All the twelve different chlorophenols were also analysed and described in (Table 2) and metals are described in (Table 3). Sludge sample were rich in organic C, H, N and S content. Vermicomposted material significantly modified the physical and chemical properties of all sets mixtures. injected volume was 0.1μl. Determination of metals
Page 4 of 12
Article 2 – Treating Paper Mill Sludge
Made with FlippingBook Digital Publishing Software