Tham khảo tài liệu 'environmental management in practice part 10', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Retrofit Approach for the Reduction of Water and Energy Consumptionin Pulp and Paper Production Processes 261 Fig. 11. Representation of the pulp production process after reduction of fresh water consumption. 262 Environmental Management in Practice No. Flowrate ton hr Concentration Mass Load Kg No. Flowrate ton hr Concentration Mass Load Kg 1 12 8700 14 2 15 12 8545 3 3 9078 16 4 17 5 18 498 6 19 7 20 8 498 21 9 22 10 23 11 24 12 25 0 0 13 0 0 Table 5. Process information for the stabilized process. On the start up of the plant ton hr of fresh water are needed. Of these ton hr are sent to the washing stage while the rest ton hr are used for dilution purposes before entering filter 3. Once the regeneration processes enter into operation and the reuse of effluent 3 is established the fresh water consumption is reduced to ton hr. From the ongoing discussion it can be seen that regeneration and reuse considerable reduce the fresh water consumption by reducing the need of using fresh water to feed the filter at a concentration of thus achieving a saving of ton hr. In the case under consideration there are various types of effluent stream with different contaminant concentrations therefore it is important the adequate selection of the regeneration process for water reuse of recycling whatever the case. Regeneration processes are of the distributed type unlike the end of pipe treatment which in the majority of cases is of centralized type. Fig. 12 shows the inlet and outlet process water flow rates. Fig.
