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Krogsgaard posted an update 7 months, 2 weeks ago
It is necessary that the consumer respects the consumption guidelines of the seaweed packers.Securing a moderate level of social acceptance for obnoxious facilities, public facilities that have negative effects, such as odors, noise, or other disruptions, is critical to infrastructure plans. For wastewater treatment plant (WWTP), also obnoxious facilities, upgrading and expanding the capacity of existing WWTP, are more important than the construction of new plants, in some regions. This study analyzes and compares the social acceptance of different types of WWTP upgrades and capacity expansion projects. Contingent valuation method is used to elicit South Korean households’ willingness to pay (WTP) for preventing the expansion of a WWTP. The aggregated WTP is interpreted from the perspective of social conflict costs. The results show that the annual mean WTP of South Korean households to prevent WWTP expansion ranges from KRW 32,058 (US $27.61) to KRW 45,793 (US $39.44) depending on spatial location, which implies that the social conflict costs for the WWTP expansion in South Korea are considerable. It is also found that an underground WWTP at current site is a best alternative to lower the social conflict costs; it is even better than relocation an existing WWTP to another area. Several related policy implications are provided based on the analysis results.The use of batch and upflow anaerobic reactors filled with polyurethane foam for pure glycerol fermentation was evaluated. The best reactor operational conditions to obtain high yield and productivity of 1,3-propanediol (1,3-PDO) as the main product and the role of the polyurethane foam in the growth and retention of suspended and attached biomass in the reactors were investigated. In the experiment at 30 °C with a batch reactor (700 mL), biomass growth was mostly as immobilized attached cells, and the achieved 1,3-PDO yield was up to 0.58 mol mol-gly-1. In the experiment (30 °C) with an upflow anaerobic reactor (717 mL), glycerol loading rates (gly-LR) ranging from 6.94 to 15.47 g gly L-1 day-1 were applied during a 102-day period. During the operation, average 1,3-PDO yield was 0.47 mol mol-gly-1, reaching a maximum of 0.51 mol mol-gly-1 at gly-LR of 13.57 g gly L-1 day-1. High 1,3-PDO productivity (5.35 to 5.44 g L-1 day-1) was obtained when gly-LR was 13.57 to 15.47 g gly L-1 day-1. Comparing the close yield values in both batch and continuous reactors and based on microbial evaluation, it is concluded that most of the 1,3-PDO generated in the continuous reactor was due to the suspended biomass retained by the foam cubes. The Clostridium genus was the predominant 1,3-PDO producer. Good yields and productivities with packed reactors were attributed to polyurethane foam used for mixed culture growth and retention. Consequently, they are worth considering for 1,3-PDO production from pure glycerol.Heavy metal-contaminated sediment is a common environmental problem. selleck chemicals In situ stabilization is an effective and low-cost method to remediate heavy metal-contaminated sediment. In this study, a red mud-based low-cost composite (RMM) was used to stabilize heavy metal-contaminated sediment. RMM was mixed with heavy metal-contaminated sediment at the doses of 0%, 1%, 3% and 5%. The CaCl2-extractable, DTPA-extractable, leachability (TCLP) and heavy metal fractions were analysed to evaluate the stabilization efficiency of RMM for heavy metals. The selected properties and microbial activities of the sediment were analysed to verify the safety of RMM to sediment. The results showed that RMM reduced the DTPA-, CaCl2- and TCLP-extractable heavy metals in sediment. At an RMM dose of 5%, DTPA-, CaCl2- and TCLP- extractable heavy metals were reduced by 7.60%, 72.34% and 69.24% for Pb; 18.20%, 76.7% and 23.57% for Cd; 32.7%, 96.50% and 49.64% for Zn; and 35.0%, 61.20% and 55.27% for Ni, respectively. TCLP- and DTPA-extractable Cu was reduced by 71.15% and 12.90%, respectively. In contrast, CaCl2-extractable Cu increased obviously after the application of RMM. RMM reduced the acid-soluble fraction of Zn by 6.99% and increased the residual fraction of Ni by 4.28%. However, the influence of RMM on the fractions of Pb, Cd and Cu was nonsignificant. In addition, the application of RMM increased the pH values of the sediment, and the microbial activity in the sediment was also obviously enhanced. These results indicated that RMM has great potential in the remediation of heavy metal-contaminated sediment.The efficiency of xylano-pectinolytic enzymes, co-produced by a single microbial strain Bacillus pumilus, was analysed for the recycling of mixed office waste paper through deinking and compared with the alkaline chemical deinking method. Enzymes showed maximum deinking at pH 8.5, pulp consistency of 10%, xylanase-pectinase dose of 12 and 4 IU per gram pulp, respectively, after 120 min of deinking period, and temperature at 50 °C. A chemi-enzymatic approach was employed with xylano-pectinolytic enzymes and various concentrations of deinking chemicals, which showed that enzyme-treated mixed office waste pulp requires only 40% chemicals for deinking, in order to get the almost same level of various handsheets properties, as obtained by the chemical method with 100% chemicals. Similarly, the effluent load of BOD and COD contents was also decreased by 17.90 and 19.75%. This combinational approach of deinking significantly improved the various properties of the handsheets and resulted in gain of 7.5, 9.38, 6.33 and 11.65% in tear factor, burst factor, breaking length and viscosity of the handsheets, while the effective residual ink concentration analysis of deinked handsheets of mixed office waste paper showed deinking efficiency of 22.45%, which revealed the removal of ink particles during enzymatic deinking steps.To explore the seasonal succession and drivers of phytoplankton communities in Guanzhong, Shaanxi Province, China, the water quality and phytoplankton communities in two typical waterbodies (Juehe Wetland Park in Xian and Xiaoxihu Lake in Xianyang) were monitored from 31 August 2017 to 31 July 2018. We identified 43 genera of phytoplankton from 7 phyla in Juehe Wetland Park and 45 genera of phytoplankton from 7 phyla in Xiaoxihu Lake. Phytoplankton communities in the two waterbodies showed significant patterns of seasonal succession. Cyanophyta (Microcystis spp.) dominated in August-September 2017 in Juehe Wetland Park, and Bacillariophyta (Navicula spp.) dominated in October 2017-July 2018. Cyanophyta (Microcystis spp.) dominated in Xiaoxihu Lake in August-November 2017, and Bacillariophyta (Synedra spp.) dominated in December 2017-July 2018. Redundancy analysis (RDA) showed that the temperature and total phosphorus were closely related to the seasonal succession of Cyanophyta and Bacillariophyta. In addition, the temperature, dissolved total phosphorus, and total phosphorus were closely related to the seasonal succession of Microcystis spp.