Hybrid Pilot Research Articles

Supervisory control evaluation on a hybrid pilot Jameson flotation cell

In this work, a metallurgical simulator, developed in a previous project, was implemented to complete the operation of a L-150 pilot Jameson flotation cell, available at the Process Control Laboratory. The cell was instrumented and its distributed control system includes the pulp to air ratio, the froth depth and the wash water flow rate controllers. A fraction of the tailings can be recycled in order to keep a constant flow rate to the downcomer, independently of the fresh feed flow rate. This hybrid system combines the real operating variables of the pilot plant (feed flow rate, air flow rate, froth depth, wash water flow rate, downcomer pressure and gas hold up) with virtual variables, characterizing the feed (solids per cent, particle size distribution by classes, grades of mineralogical species by classes). All these variables are fed to a simulator to predict the characteristics of the concentrate and tailings (mass flow rate, grades, particle size distribution).The expert control strategy developed is based on the maximization of the cell Cu recovery subject to the technical specifications of the produced concentrate are met. To achieve this, the quality of the concentrate and tailings, predicted by the metallurgical simulator, are monitored on line. The cell recovery is estimated when an on line steady state test is passed. The expert system modifies the set points of the distributed control system. The supervisory control includes two main routines: expert feedback control, acting whenever a steady state is reached, and expert feed forward control, to compensate for measured disturbances on the characteristics of the feed. Several cases for different feed conditions are discussed and evaluated.

Application of nanofiltration pretreatment to remove divalent ions for economical seawater reverse osmosis desalination

To minimize scale formation potential in the applications of reverse osmosis (RO) membranes as a pretreatment unit, relatively loose nanofiltration (NF) membrane systems coupled with ultrafiltration (UF) were used to remove divalent ions from seawater. However, the UF did not reject any ions because of pore size. The rejection of divalent ions by NF was in order of sulfate (>95%), magnesium (>60%), and calcium (>30%) in every rejection experiment based on water recovery rate (40, 50, 60, 70, and 80%). In the UF/NF/RO hybrid pilot system, most of the divalent (>99%) and the monovalent (>97%) ions were effectively rejected with slightly increased divalent ion rejection compared to the UF/RO system. Seawater temperature influenced rejection of ions with regards to either the diffusion- or convection-dominant transport of ions through the membrane pores. Electric power consumption was also compared between the UF/NF/RO process and the UF/RO process. For different salinity conditions (28,000 and 45,000 mg/L of total dissolved solids), the lowest energy consumption by NF/RO was 3.3 and 6 kWh/m3 with recovery of 80% for NF and 40% for RO, respectively.

The genomic medicine model: an integrated approach to implementation of family health history in primary care.

As an essential tool for risk stratification, family health history (FHH) is a central component of personalized medicine; yet, despite its widespread acceptance among professional societies and its established place in the medical interview, its widespread adoption is hindered by three major barriers: quality of FHH collection, risk stratification capabilities and interpretation of risk stratification for clinical care. To overcome these barriers and bring FHH to the forefront of the personalized medicine effort, we developed the genomic medicine model (GMM) for primary care. The GMM, founded upon the principles of the Health Belief Model, Adult Learning Theory and the implementation sciences, shifts responsibility for FHH onto the patient, uses information technology (MeTree©) for risk stratification and interpretation, and provides education across multiple levels for each stakeholder, freeing up the clinical encounter for discussion around personalized preventive healthcare plans. The GMM has been implemented and optimized as part of an implementation-effectiveness hybrid pilot study for breast/ovarian cancer, colon cancer and thrombosis, and risk for hereditary cancer syndromes in two primary care clinics in NC, USA. This paper describes the conceptual development of the model and key findings relevant for broader uptake and sustainability in the primary care community.

Characterization of Biomass Activity in Conventional and Hybrid MBR Pilot Plants by Means of Respirometric Techniques

Characterization of Biomass Activity in Conventional and Hybrid MBR Pilot Plants by Means of Respirometric Techniques

Evaluation of PPCPs removal in a combined anaerobic digester-constructed wetland pilot plant treating urban wastewater

The removal efficiency of 16 pharmaceuticals and personal care products (PPCPs) from urban wastewater (dissolved and particulate phases) was evaluated for the first time in a hybrid pilot plant consisting of an upflow anaerobic sludge blanket reactor followed by two sequentially connected horizontal flow constructed wetlands: a surface flow wetland (SF CW) and a subsurface flow wetland (SSF CW). Whereas the PPCP removal associated with the dissolved phase exhibited a seasonal pattern, the fraction associated with the suspended solids showed less seasonality. In the dissolved phase, the overall removal efficiency in summer ranged from 70% to 85% for salicylic acid (SAL), methyl dihydrojasmonate, caffeine (CAF), ketoprofen and triclosan, whereas in winter it declined for most of the PPCPs to between 30% and 50%, except for CAF and SAL (>80%) and carbamazepine and butylated hydroxyl toluene (11–18%). In the suspended solids, the removal exceeded 80% for most of the target PPCPs. The efficiency of the different treatment steps was also compound-dependent, but the SF CW generally exhibited the highest removal efficiency for most of the contaminants analyzed. The characterization of the organic matter retained in the wetland gravel beds revealed the occurrence of hydrophobic contaminants such as phthalate esters and fragrances at moderate concentrations (i.e., up to 3.5 μg kg −1), which declined strongly over the course of the different treatment steps. In the SF CW, the net mass accumulation rates of tonalide and galaxolide were 4 and 23 g y −1 respectively, whereas in the SSF CW they were 0.3 and 1.8 g y −1 respectively.

Channel State Information Feedback with Zero-Overhead in Closed-Loop MIMO System

Dramatic gains in channel capacity can be achieved in the closed-loop MIMO system under the assumption that the base station (BS) can acquire the downlink channel state information (CSI) accurately. However, transmitting CSI with high precision is a heavy burden that wastes a lot of uplink bandwidth, while transmitting CSI within a limited bandwidth leads to the degradation of system performance. To address this problem, we propose a zero-overhead downlink CSI feedback scheme based on the hybrid pilot structure. The downlink CSI is contained in the hybrid pilots at mobile terminal (MT) side, fed back to BS via the uplink pilot channel, and recovered from hybrid pilot at BS side. Meanwhile the uplink channel is estimated based on the hybrid pilot at BS side. Since transmitting the hybrid pilots occupies the same bandwidth as transmitting traditional code division multiplexing based uplink pilots, no extra uplink channel bandwidth is occupied. Therefore, the overhead for downlink CSI feedback is zero. Moreover, the hybrid pilots are formed at MT side by superposing the received analog downlink pilots directly on the uplink pilots. Thus the downlink CSI estimation process is unnecessary at MT side, and MT's complexity can be reduced. Numerical Simulations prove that, the proposed downlink CSI feedback has the higher precision than the traditional feedback schemes while the overhead for downlink CSI feedback is zero.

Selection of variables using factorial discriminant analysis for the state identification of an anaerobic UASB–UAF hybrid pilot plant, fed with winery effluents

Anaerobic wastewater treatment has become a widely used method for wastewater depuration, and has been applied in a wide range of situations, from urban wastewater to highly toxic industrial wastewater. Particularly it has been successfully applied to the treatment of the beverage industries effluents. To avoid the destabilization of the system a monitoring diagnosis and control system of the depuration processes is necessary. The cost of this system is an important issue, that depends on the number of parameters that must be controlled for an adequate performance of a wastewater plant control system. This work shows how the classic statistical classification techniques can be applied to determine the number variables that must be monitored to achieve an adequate performance of anaerobic UASB-UAF hybrid Pilot Plant monitoring and control system. The obtained results had not been unique, so different combinations of variables can be selected for a good wastewater treatment process control. Economic or technical criteria may be considered to determine the final variables set in each particular situation.

Water quality profiles during nitrification in a pilot distribution system study

Biochemical nitrification was investigated in a large scale pilot study using aged galvanized steel, unlined cast iron and a hybrid pilot distribution systems consisting of a combination of aged polyvinyl chloride, lined cast iron, unlined cast iron and galvanized steel pipes. Variations of free ammonia, nitrate, nitrite, dissolved oxygen (DO) and chloramine residual in the distribution system water are discussed for each pipe material. Chloramine depletion, DO depletion, free ammonia release, heterotrophic plate count (HPC) growth, NO 2 –N and NO x –N measured as the sum of nitrite and nitrate N were dependent on pipe material. Galvanized steel pipe had the highest chlorine demand and produced conditions without residuals, which corresponded to the higher HPC proliferation and DO consumption and the lowest nitrification. The greatest production of nitrite and nitrate was observed in unlined cast iron pipe. Denitrification was observed in the unlined cast iron pilot distribution system following residual loss and development of anoxic conditions.

An expert system for monitoring and diagnosis of anaerobic wastewater treatment plants

In this paper, an expert system (ES) developed for the monitoring and diagnosis of anaerobic wastewater treatment plants (AWT), is presented. The system was evaluated in a hybrid pilot plant of 1.1 m 3 located in an industrial environment for the treatment of wastewaters from a fibreboard production factory. The reactor is a hybrid USBF, combining an upflow anaerobic sludge blanket (UASB) in the lower part and an upflow anaerobic filter (UAF) at the top.

In-plant corrosion test results of candidate materials in coal gasification plants

In-plant corrosion tests were carried out in two coal gasification plants. This research was sponsored by the Agency of Industrial Science and Technology and the New Energy and Industrial Technology Development Organization (NEDO). At the HYBRID pilot plant (fluidized-bed gasifier), the test programme was conducted to evaluate the low temperature corrosion behaviour of construction alloys. The corrosion rate is strongly dependent on the temperature and peaks at about 300°C. At the HYCOL pilot plant (entrained-bed gasifier), the main purpose of the test programme was to obtain corrosion data on candidate heat exchanger tubing alloys. The test alloys were carbon steel, Cr-Mo steels, austenitic stainless steels, Ni-base alloys and diffusion coatings. According to the first examination results from the heat recovery boiler, the corrosion resistance of the test alloys increases with Cr content in the alloy. Cr-Mo steels are severely attacked through sulfidation and austenitic stainless steels are slightly atta...