Comparison Study of Manometric Respirometric Test and Common Chemical Methods in the Determination of BOD bold7 in a Pulp and Paper Mill's Wastewaters

The biological oxygen demand (BOD) test is widely used in many wastewater treatment plants. The conventional BOD tests are usually time-consuming and the results are often out of date for process control purposes. The aim of this research was to compare the manometric respirometric test with common chemical methods in the determination of BOD of wastewater from a pulp and paper mills as well as to evaluate the BOD 7 values of both wastewaters from the short-term respirometric measurements. The results showed that there were differences in the BOD7 values of paper mill samples measured by conventional and respirometric methods. The main cause was found to be the dilution solution used in the conventional BOD tests. Using the same mineral solution in the respirometric measurements diminished the difference remarkably. Evaluation of the BOD7 value after two or three days incubation was proved to work very well and the estimated results were close to measured values (deviations 1%–12%)

Assessing industrial pollution by means of environmental samples in the Kemi-Tornio region

Abstract The results of the comparison of various dissolution methods for sulphur showed, that HNO3 together with H2O2 gave more complete decomposition of organic components than HNO3 alone. The acid procedure with a mixture of HNO3+H2O2 slightly underestimated the S concentrations of plant material. The losses of sulphur were the highest in the dry ashing digestion procedure (HF(DAC)). The Leco combustion technique with infrared (IR) detection gave good precision and accuracy for sulphur. For the determination of heavy metals in plant materials, both the HNO3 and HNO3+H2O2 procedures were especially effective for determining Cr. However, the HNO3+HClO4 procedure gave lower results, and HF and HF(DAC) procedures greater values for Cr. Sulphur accumulation in pine needles around the pulp and paper mills was clearly higher than other points in the Kemi area. For example, within a radius of about 1-1.5 km around the mills of Oy Metsä-Botnia Ab Kemi Mills, the sulphur concentrations for (C) and (C+1) needles were 28 % and 26 % higher than those in the corresponding background samples collected in Kuivaniemi at a distance about 25 km from Kemi. Pine needles do not appeared to be appropriate a method for monitoring the accumulation of Fe, Zn, V and Pb emitted from pulp and paper mills. However, the Ca concentrations in (C+1) needles in the vicinity of the Oy Metsä-Botnia Ab Kemi Mills was 48 % higher than the average Ca concentration calculated from all (C+1) needles; thus it is likely that part of the Ca in the needles is derived from the mills. The regional distribution pattern of Cr and Ni in mosses in the Kemi-Tornio area in 2000 showed clearly that the most polluted area (Cr > 200 μg/g and Ni > 20 μg/g) appeared to lie within a few kilometres of the ferrochrome and stainless steel works of AvestaPolarit Stainless Oy. Within this area, the Cr concentrations in mosses were 4-13 times higher than those outside the urban area of Tornio. The area most polluted by the opencast chromium mining complex (Cr > 200 μg/g and Ni < 20 μg/g) appeared to be in the immediate vicinity of complex. All the 95th percentile values for TSP (total suspended particles) in the mine area of AvestaPolarit Chrome Oy Kemi Mine were below the current Finnish air quality limit value of 300 μg/m3. However, the 98th percentile value exceeded the Finnish air quality guideline value of 120 μg/m3 at one monitoring site. According to leaching studies, the sum of calculated annual airborne pollution impact of water-soluble fraction (H2O) and environmentally mobile (CH3COONH4) fraction from the AvestaPolarit Chrome Oy Kemi Mine was Cr 1.2 kg, Fe 29 kg, Cu 63 kg, Ni 2.5 kg and Cd < 100 mg. According to the homogeneity studies of heavy metal deposition on TSP filters, Cr, Ni, Cu and Fe were non-uniformly distributed over the glass fibre filters. The rsd values varied between 5.4-33.9 % for Cr, between 7.5-35.0 % for Ni, between 3.6-25.9 % for Cu, and between 6.6-19.9 % for Fe

Characterization of primary and secondary wastewater treatment sludge from a pulp and board mill complex to evaluate the feasibility of utilization as a soil amendment agent and a fertilizer product

In this study, we have determined the main important physical and chemical properties as well as the heavy metal concentrations of the primary and secondary wastewater treatment sludge from a pulp and board mill complex located in Finland in order to evaluate the utilization of these by-products as a soil amendment agent or a fertilizer product. Easily soluble Ca, Mg, K, Na, P and S concentrations in the sludges were extracted by ammonium acetate (CH3COONH4) and easily soluble Cu, Mn and Zn concentrations by CH3COONH4 + Na2EDTA. For the determination of total nutrient and total heavy metal concentrations in sludges, they were digested using aqua regia (3 mL HCl + 9 mL HNO3). The total heavy concentrations in the primary sludge were lower than the Finnish heavy metal limit values for fertilizer products. In the secondary sludge, all other total heavy metals than the total Cd concentration (4.8 mg/kg; d.w.) were lower than the heavy metal limit values for fertilizer products. Due to the low total heavy metal concentrations, which were lower than the Finnish limit values for fertilizer products, the primary sludge is a potential fertilizer. Although the total Cd concentration (4.8 mg/kg; d.w.) in the secondary sludge exceed the limit value of 1.5 mg/kg (d.w.) for fertilizer products, this residue may be used as a soil improver, a growing media or as a fertilizer product in landfill sites or in other closed industrial areas, because the Finnish limit values for fertilizer products are not applied at these sites.Peer reviewe

Characterisation of Municipal Sewage Sludge as a Soil Improver and a Fertilizer Product

In this study, we have determined the main important physical and chemical properties of municipal sewage sludge and compared them to the requirements of the Finnish Fertilizer Product Act and Fertilizer Product Decree in order to assess the potential utilization of this by-product as a fertilizer. Except for Hg (1.4 mg/kg d.m.), the total concentrations of Cd, Cu, Ni, Pb, Zn, Cr and As in our sewage sludge were lower that the Finnish maximum permissible heavy metal concentrations for sewage sludge used as a fertilizer products. However, the sewage sludge may be utilized as a soil improver, a growing media or as a fertilizer product in landfill sites (e.g. surface structures) or in other closed industrial areas, because the above mentioned Finnish limit values are not applied at these sites. If the sewage sludge is to be utilized in these kinds of areas, an environmental permit may be needed. According to BCR-extraction, the lowest release potential (solubility) from the sample matrix was observed for sulphur(58.4 %) and the highest for Cd (100 %).Peer reviewe

Fertiliser Properties of Wastewater Sludge and Sludge Ash - A Case Study from the Finnish Forest Industry

Publisher Copyright: © 2023 Juha Oksanen et al., published by Sciendo.In this case study we compared the fertiliser properties of an industrial wastewater treatment sludge and a sludge ash to the requirements of the Finnish Fertiliser Product Decree. The sludge was obtained from the activated sludge wastewater treatment plant of a Finnish non-integrated pulp mill. The sludge was furthermore incinerated at a laboratory in a muffle furnace (850 °C) to obtain sludge ash. The total Cd (4.9 mg/kg d.m.) concentration in the pulp sludge exceeded the Finnish limit value (1.5 mg/kg d.m.) for fertiliser products used in agriculture. In the sludge ash, the total concentration of Cd (39 mg/kg; d.m.) exceeded the Finnish limit value (25 mg/kg d.m.) for ash fertilisers used in forestry. These results restrict the potential reuse options of these residues. However, from the utilisation point of view, the enrichment of essential plant macro-nutrients was most notable, resulting to the following total concentrations of these elements in the sludge ash: P (26,000 mg/kg d.m.), S (40,000 mg/kg d.m.), K (11,000 mg/kg d.m.), Ca (83,000 mg/kg d.m.) and Mg (10,000 mg/kg d.m.). Therefore, we conclude that, the converting of sludge into ash may promote the reuse of this wastewater treatment residue to a more value-adding fertiliser by-product to be used as a soil improver and growing medium in landscaping or landfills sites or other closed industrial areas, where heavy metal limit values for fertilisers are not applied in Finland.Peer reviewe

Comparison of Untreated, Lime-Stabilised and Composted Wastewater Sludges from a Pulp, Board and Paper Mill Integrate as a Fertiliser Product

Funding Information: kindly performed all chemical analysis. This study was part of the joint research programme NSPPulp funded by TEKES, the Finnish Funding Agency for Technology and Innovation (nowadays, Business Finland). Publisher Copyright: © 2021. All Rights Reserved.In this study, the physical and chemical properties of untreated, lime-stabilised and composted wastewater sludges from a Finnish pulp, board and paper mill integrate were compared in order to assess their fertiliser properties based on the requirement of the Finnish Fertilizer Product Decree. Furthermore, the extraction properties of heavy metals in the sludges were assessed by the three-stage sequential extraction procedure of the Community Bureau of Reference (BCR) and the solubility indices for heavy metals were calculated in order to evaluate the release potential of elements from the sample (sludge) matrix. The results of this study indicated that the total heavy metal (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) concentrations in all sludges were lower than the statutory Finnish limit values for fertiliser products. However, the untreated sludge required either lime-stabilisation or composting in order to fulfil the Finnish maximum concentrations of pathogens (coliforms and Escherichia coli) for fertiliser products.Peer reviewe

Comparison of the fertilizer properties of ash fractions from medium-sized (32 mw) and small-sized (6 mw) municipal district heating plants

Due to the low heavy metal concentrations, the bottom ash from a 32 MW municipal district heating plant was determined to be a potential forest fertilizer as such. However, additional Ca would be needed, because its Ca concentration of 1.9- % (d.w.) was lower than the statutory Finnish minimum limit value of 6.0-% (d.w.) for Ca in forest fertilizer. Due to the elevated As concentration (53.0 mg/kg; d.w.) in the fly ash from the 32 MW municipal district heating plant, and Cr concentration (620 mg/kg; d.w.) in the ash fraction (i.e. mixture of the bottom ash and fly ash) from the 6 MW municipal district heating plant, which exceed the limit values of 30 mg/kg (d.w.) and 300 mg/kg (d.w.) for As and Cr, respectively, these residues are not suitable as forest fertilizers. Although these ash fractions cannot be used as a forest fertilizer as such, they can be used for the landscaping of landfills or in industrial and other areas that are closed to the public. However, an environmental permit is then needed.</p

Chemical fractionation method for characterization of biomass-based bottom and fly ash fractions from large-sized power plant of an integrated pulp and paper mill complex

The aim of this study was to extract the biomass-based bottom and fly ash fractions by a three-stage fractionation method for water-soluble (H2O), ammonium-acetate (CH3COONH4) and hydrochloric acid (HCl) fractions in order to access the leaching behaviour of these residues. Except for Mo, S, Na and elements whose concentrations were lower than the detection limits, the extractable element concentrations in both ash fractions followed the order H2O&lt;CH3COONH 4&lt;HCl. The elements concentrations in this study were also lower than those in our previous studies, in which certain extraction stages followed the BCR extraction procedure.</p

Application of a modified BCR approach to investigate the mobility and availability of trace elements (As, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, Zn, and Hg) from a solid residue matrix designed for soil amendment

Trace element speciation of an integrated soil amendment matrix was studied with a modified BCR sequential extraction procedure. The analysis included pseudo-total concentration determinations according to USEPA 3051A and relevant physicochemical properties by standardized methods. Based on the results, the soil amendment matrix possessed neutralization capacity comparable to commercial fertilizers. Additionally, the pseudo-total concentrations of all trace elements included in the Finnish regulation for agricultural fertilizers were lower than the respective statutory limit values. According to chemical speciation, the lability of trace elements increased in the following order: Hg &lt; Cr &lt; Co &lt; Cu &lt; As &lt; Zn &lt; Ni &lt; Pb &lt; Cd &lt; V &lt; Mo &lt; Ba. The validity of the BCR approach as a tool for chemical speciation was confirmed by the additional acid digestion phase. Recovery of trace elements during the procedure assured the validity of the approach and indicated good quality of the analytical work.</p

Integration of solid residues from the steel and pulp and paper industries for forest soil amendment

Beneficial utilisation of process industry residues provides possibilities to reduce energy consumption, to avoid environmental impacts caused by increasing land-filling and promotes sustainable management of natural resources. As traditional utilisation of steel industry residues lies within the realm of civil construction, complementary applications could be found from the integration with pulp and paper industry residues to promote sustainable forest management through forest soil amendment. In our study we show that three different soil amendment matrices, providing slow release and materials handling advantages, were successfully produced according to conventional cement testing practices. The concepts we develop for forest soil amendment incorporate the use of fly ash in tandem with granulated blast furnace or steel slag as binder materials, the utilisation of paper mill sludge as reactive aggregate and the use of green liquor dregs and lime waste from chemical pulping as alkaline components. The neutralising (35.8-38.6%) and reactivity (33.3-38.0%) values (expressed as Ca-equivalents d.w.) with supporting high pH-values (12.9-13.0) indicate liming and buffering capacities of the test matrix materials are comparable to commercial ground limestone products. Additionally, concentrations of Ca, K and Mg and concentrations of Cu, Mn and Zn were found to be higher than organic and mineral soils normally found in the Ostrobothnia region of Northern Finland. Only under severe leaching test conditions (HNO3 and HCl microwave digestion) did the total concentration of Cr in the soil amendment matrix exceed respective Finnish statutory limit value set for the use of fertilisers in forestry. However, as illustrated by the leaching procedure, less than a fifth of the total Cr is likely to become mobile in conditions normally found in nature.</p