Sludge treatment system
When liquefying sludge, e.g as in U.S. Pat. No. 6,808,636, the combination of temperature, pH, and shearing, is synergistic. Described here is a system that provides for collating test sampling and full-scale data inputs, recording achieved results and the engineering parameters that achieved those particular results. The data is presented in e.g a table format, which assists design engineers to zero-in on the combinations of parameters that will likely give the desired results.
1. Procedure for liquefying dewatered sewage sludge, here termed reactor-sludge, to a target-viscosity, including:
providing respective event-records of a number N of separate sludge-liquefaction-events, where N is three or more;
the event-records comprise respective aggregations of records of the following event-parameters, namely:
(i) the quantity or flowrate of dewatered event-sludge in the sludge-liquefaction event;
(ii) the solids percentage of the event-sludge;
(iii) the temperature of the event-sludge during liquefaction;
(iv) the shearing power or energy applied to the event-sludge to procure liquefaction;
(v) the final-viscosity of the liquefied event-sludge, as procured by that shearing power or energy at that temperature;
making a compilation of the N event-records;
identifying, in the compilation, a target-record, being one of the N event-records in which the final-viscosity matches the target-viscosity;
determining the levels of the event-parameters in the target-record, these levels being termed the target-procurement-levels;
passing dewatered reactor-sludge through a reactor, for liquefaction to the target-viscosity;
the reactor contains a heater and a shearer;
liquefying the reactor-sludge to the target viscosity, in the reactor, by:
(a) so operating the heater that the temperature of the reactor-sludge in the reactor matches the target-procurement-level of temperature; and
(b) so operating the shearer that the power or energy applied to the reactor-sludge in the reactor matches the target-procurement-level of power or energy; and
after liquefaction of the dewatered reactor-sludge, discharging the liquid reactor-sludge from the reactor.
2. As in claim 1 , including compiling the N event-records in such form as to enable the event-records to be presented in the form of a spreadsheet or table, in which:—
the spreadsheet or table includes the N event-records as respective rows or lines of the table; and
the spreadsheet or table includes the event-parameters as respective columns of the table.
3. As in claim 2 , including:
wherein the event-record includes a record of the pH of the event-sludge, during sludge-liquefaction-events, as one of the event-parameters;
identifying the target-record also as being one of the N event-records in which the pH in the event-record matches the pH of the reactor-sludge; and
matching the pH of the reactor-sludge to the pH of the target-record.
4. As in claim 2 , including compiling one of the event-records by a full-scale-batch procedure, which includes:
in an event-reactor containing a batch of dewatered event-sludge having a mass of one tonne or more;
creating one of the sludge-liquefaction-events by liquefying the batch of dewatered event-sludge, by shearing and heating the event-sludge in the event-reactor;
creating an event-record by noting the event-parameters of the sludge-liquefaction-event, including noting the amount of energy applied to the batch of event-sludge, per unit mass of the batch, by way of shearing; and
entering that event-record as a line or row of the spreadsheet or table.
5. As in claim 2 , including compiling one of the event-records by a small-batch procedure, which includes:
providing a laboratory-batch of dewatered event-sludge, and placing the same in a test reactor;
creating one of the sludge-liquefaction-events by liquefying the laboratory-batch of dewatered event-sludge, by shearing and heating the event-sludge in the test reactor;
creating an event-record by noting the event-parameters of the sludge-liquefaction-event, including noting the amount of energy of shearing applied to the batch of event-sludge, per unit mass of the event-sludge; and
entering that event-record as a line or row of the spreadsheet or table.
6. As in claim 2 , including compiling one of the event-records by a full-scale-continuous procedure, which includes:
conducting dewatered sludge through an event-reactor at a flowrate of one tonne per day or more;
creating one of the sludge-liquefaction-events by liquefying the dewatered event-sludge by shearing and heating the event-sludge passing through the event-reactor;
creating an event-record by noting the event-parameters of the sludge-liquefaction-event, including noting the level of power of shearing applied to the event-sludge per unit of mass-throughflow-rate of the event-sludge; and
entering that event-record as a line or row of the spreadsheet or table.
7. As in claim 2 , including compiling one of the event-records by a sample-continuous procedure, which includes:
conducting a sample of dewatered event-sludge through a test reactor;
creating one of the sludge-liquefaction-events by liquefying the dewatered event-sludge, by shearing and heating the event-sludge passing through the test reactor;
creating an event-record by noting the event-parameters of the test, including noting the level of power of shearing applied to the event-sludge per unit of mass-throughflow-rate of the event-sludge; and
entering that event-record as a line or row of the spreadsheet or table.
8. As in claim 1 , including:
making the compilation of the N event-records such that, either:—
(a) at least one of the respective final-viscosities recorded in the N event-records is higher than the target-viscosity by no more than twenty percent;
(b) or at least one of the respective final-viscosities recorded in the N event-records is lower than the target-viscosity by no more than twenty percent;
(c) or both.
9. As in claim 1 , wherein the N records differ substantially from each other, as to the power or energy of shearing, as to the temperature to which the event-sludge is raised, or as to the extent to which the event-sludge is dewatered prior to being sheared and heated.
10. As in claim 1 , wherein, in respect of all N event-records, the solids percentage of the event-sludge is ten percent solids or greater, and the final-viscosity is 15,000 centipoise, or lower.
11. As in claim 1 , wherein all N event-records are compiled in respect of event-sludge of substantially the same composition.
12. As in claim 1 , wherein the reactor-sludge is sludge that has been dewatered to a solids percentage of ten percent solids or greater.
13. As in claim 1 , including identifying the target-record also as being one of the N event-records in which the solids percentage in the event-record matches the solids percentage of the reactor-sludge.
14. As in claim 1 , wherein the final-viscosity matches the target-viscosity in that the final-viscosity is within twenty percent of the target-viscosity.
15. As in claim 1 , wherein the temperature of the reactor-sludge in the reactor matches the target-procurement-level of temperature in that the temperature of the reactor-sludge is within ten centigrade degrees of the target-procurement-level of temperature.
16. As in claim 1 , wherein the shearing power or energy applied to the reactor-sludge in the reactor matches the target-procurement-level of power or energy in that the shearing power or energy applied to the reactor-sludge is within twenty percent of the target-procurement-level.