Water reuse in the post-tanning process: minimizing environmental impact of leather production

The post-tanning wastewater is very diversified, as the post-tanning stage should meet the desirable properties of the leather for the final product, with low standardization of the process (compared to beamhouse and tanning). This makes post-tanning effluent reuse less feasible, and reuse in the post-tanning stage still needs to be explored. This work aims to evaluate the reuse of liquid effluents in the post-tanning process. The work methodology consisted of (i) characterization of water streams (groundwater, liquid effluent after primary treatment, and liquid effluent after secondary treatment); (ii) pilot-scale post-tanning tests using groundwater, primary effluent, and secondary effluent; (iii) characterization of the residual baths from pilot-scale tests (pH, conductivity, total solids, chemical oxygen demand, biochemical oxygen demand, chloride, hardness and oil and grease); and (iv) testing the leather obtained for total sulfated ash and organoleptic properties. Results showed that the primary effluent and the secondary effluent could be reused in pilot-scale post-tanning tests. There was an increase in the conductivity of the residual baths when liquid effluents were reused, which confirms the accumulation of salts in the effluents after their reuse.

​Influence of Formulated Palm Mill Effluent and Bat Guano Mixture on Maize Performance and Soil Chemical Properties in Delta State, Nigeria

Background: Utilization of palm mill liquid effluent and bat guano as organic fertilizer was initiated in year 2019 and 2020. The palm oil mill effluent and bat guano were used to produce compost and was tested on maize and soil properties in Asaba, Delta State. Methods: The compost was applied at 0, 2.5, 5.0, 7.5 and 10 ton/ha and replicated four times in randomized complete block design for two years. Plant height, leaf area, stem girth were assessed at maturity whereas yield parameters and soil chemical properties measured at harvest. Data collected were analysed with analysis of variance and means separated with Duncan’s multiple range test at 5% level of probability. Result: Compost significantly increased maize yields and soil properties. The 10 t/ha gave the highest dry matter yield (22.1±2.71 and 36.2±7.47 t/ha), weight of 1000 grains (324±41.0 and 364±63.3) and grain yield (5.2±1.04 and 6.4±1.61 t/ha) in both years, respectively. It also, had the highest soil pH value, organic carbon, total nitrogen and available phosphorus. The palm mill liquid effluent and bat guano mixtures have the potentials to be used as organic fertilizer for maize production.

Isolation and Study of Biodegradation Capability of Hydrocarbonoclastic Bacteria from Industrial Waste Lubrication Oil Contaminated Sites

A research was carried out on Isolation and study of biodegradation capability of hydrocarbonoclastic bacteria from industrial waste lubricant oil contaminated sites. 12 different bacterial cultures are isolated from the soil samples collected from liquid effluent dump site of black galaxy granite, chimakurthy, prakasam Dist, and auto motive lubrication oil replacement garages, Auto Nagar, Vijayawada. Among the 12isolates 10 isolates were found to have capability of degrading used industrial lubrication oil VG 320 collected from NSL textiles LTD, Guntur. Among the isolates tested the isolate no BG4 obtained from liquid effluent dump site gave the maximum biodegradation potential of 18.78mm2followed by BG7 of 15.36, BG1 of 14.07and BG8 of 10.56 mm2 and the isolate no AL1 from automotive lubrication oil replacement garage soil sample found to be 9.03mm2 degradation potential. These isolates were identified based on physical and biochemical characters as Pseudomonas, Bacillus, Proteus, Flavobacterium and Enterococcussps respectively. For the future, our study will be focused on several data like the species of isolates, the optimal activity of isolates to degrade several Industrial lubricant oils.

THE CONCEPTUAL DESIGN FOR LIQUID EFFLUENT TREATMENT OF UO2 KERNEL FABRICATION

THE CONCEPTUAL DESIGN FOR LIQUID EFFLUENT TREATMENT OF UO2 KERNEL FABRICATION. The pebble fuel for HTGR is prepared through fabrication of UO2 kernel, coated particle and spherical element fuel. In the fabrication of UO2 kernel by external gelation method, a multicomponent of liquid effluent is generated. Therefore, the liquid effluent is required to be treated for safety reason before disposed to waste storage. In this paper, the conceptual design for the liquid effluent treatment of UO2 kernel fabrication is performed with the simulation process using CHEMCAD software. CHEMCAD is a software that can be utilized for chemical process design. The results showed that the proposed conceptual design is able to separate valuable components: isopropyl alcohol (IPA) and tetrahydrofurfuryl alcohol (THFA). The flowrate of IPA product is 5.28 kg/h with purity of 0.99 in mass fraction and the flowrate of THFA product is 1.01 kg/h with purity of 0.99 in mass fraction.Keywords: liquid effluent, UO2 kernel, CHEMCAD, HTGR.

Discharge Capacity Analysis of Liquid Effluent Discharge System at CPR1000 Nuclear Power Plant

CPR1000 nuclear power plant is a nuclear power plant supported by China’s advanced million-kilowatt (1000 mw) pressurized water reactor (PWR) nuclear power technology introduced by China general nuclear power corporation (CGN). The liquid effluent discharge system is an important module of CPR1000 nuclear power plant. The discharge capacity of the liquid effluent discharge system directly affects the operation safety and stability of CPR1000 nuclear power plant. Therefore, this paper takes the liquid effluent discharge system of CPR1000 nuclear power plant as the research object, on the basis of a brief overview of the structure of the liquid effluent discharge system, combined with the technical characteristics of the liquid effluent discharge system, the discharge capacity of the liquid effluent discharge system is further analyzed.