Principles and Modes of Distillation in Desalination Process

Distillation has been a very important separation technique used over many centuries. This technique is diverse and applicable in different fields and for different substances. Distillation is important in the desalination section. Various principles are used in desalting seawater and brackish water to fulfill the demands of freshwater. This work explains the modes and principles of distillation in desalination, their types, present improvement, challenges, and limitations as well as possible future improvements. The first and primary mode of distillation is the passive type. As times went by and the demand for freshwater kept increasing, other modes were introduced and these modes fall under the active distillation type. However, each mode has its own advantages, disadvantages, and limitations over each other. The principles and modes of distillation are as significant as understanding the energy sources needed for distillation. Hence, they are the basic knowledge needed for future innovation in the desalination industries.

Chemical Plant Utility – Nitrogen System Design

The study is been conducted to understand the different techniques to separate nitrogen from atmospheric air. Separation of nitrogen takes place by following techniques: Cryogenic air separation, Pressure swing adsorption and Membrane separation technique. Cryogenic air separation operates at a very low temperature, which uses the principle of rectification to separate nitrogen at a very high purity (99.999%). Pressure swing adsorption rely on the fact that higher the pressure, more the gas is adsorbed which results in high purity (95-99.99%) of nitrogen. Membrane separation technology is the process that uses hollow fibre membranes to separate the constituent gases in air, which gives the purity in the range of 93%-99.5%. After the comparative study, it is understood that membrane separation technique is the most efficient technology based on the cost, purity, flexibility in terms of adjusting the purity, maintenance, availability; it operates without heating and therefore uses less energy than conventional thermal separation processes. Different step designs of membrane separation techniques are discussed. A Process Flow Diagram and Piping Instrumentation Diagram is been added for single step membrane separation technique. Keywords: Atmospheric air, nitrogen, Cryogenic air separation, Pressure swing adsorption, Membrane separation technique.

P013 HOW TO IMPROVE TREATMENT OF COMPLEX INCISIONAL HERNIAS IN OBESE PATIENTS: A SINGLE-CENTRE STUDY, AN EVALUATION OF LESS-OPEN TECHNIQUE AND FREE-FIXATION TECHNIQUE

Aim Surgery of a complex incisional hernia in an obese patient is a challenging procedure for hernia surgeons. The aim of a new approach is to reduce complications such as pain and wound events, without increasing the number of recurrences. Material and Methods Adults with BMI more than 35 who underwent open, elective operation of a complex incisional hernia (with horizontal diameter more than 12cm) including posterior component separation technique with TAR (transversus abdominis muscle release) and retromuscular synthetic large-pore mesh placement, were identified. Patients were divided into 2 groups: The first group was treated with standard open technique with fixation using interrupted stitches, and the second group was treated with a technique using light hook and no or reduced fixation in the upper and lower pole of the mesh. For post-operative complication evaluation, the Clavien-Dindo classification was used. We have also evaluated an average operation time, length of stay, duration of opioid need. The long-term follow-up was 6 – 48 months. Results There was no significant difference in length of stay, the need of analgetic treatment, and hernia recurrence. Shorter operation time, and lower occurrence of surgical-site infections were reported in the second group, but it was not significant. Conclusions Open posterior component separation technique with TAR using large-pore mesh and no/minimal fixation seems to be a safe and sufficient method of treatment for complex incisional hernias in obese patients. Alternative methods may reduce early complications and pain and do not increase number of recurrences. A larger group of patients and longer follow-up should be needed to improve these findings.

Analyzing the functional structure of pottery jiandiping amphorae

There are numerous, controversial theories on the function of the jiandiping amphorae as Yangshao culture water-drawing vessel, wine vessel, or other. This paper discusses jiandiping amphorae functional form from a typological perspective and presents the view from molding technique. The primary function of the pointed bottom concerned sedimentation, yet the vessel’s small opening was poorly adapted to cereal fermentation. The large jiandiping amphora was less transportable but better suited to long-term storage and sedimentation: wine decanted into medium- or small-sized flat-bottom vessels or jiandiping amphora was easily transferred and used, and decanting served to remove any sediment from turbid wine. Functional differences between the large and small jiandiping amphorae explain varying functions and uses of double-loop handles. The development of sediment separation technique is the key reason for the disappearance of the jiandiping amphorae.

A Variation of the Components’ Separation Technique that Preserves the Semilunaris for Treatment of Abdominal Wall Deformities

The variation of the components’ separation technique, which uses the anterior rectus sheath and the release of the oblique muscles, proved to be effective in tension reduction. This paper aimed to present the initial experience using a variation that preserves semilunaris through the incision of the lateral aspect of the rectus sheath. All of the 12 patients presented an abdominal wall defect that included incisional hernia, peritoneostomy, lateral implantation of the rectus muscle, and defect secondary to TRAM flap. The separation was done in the following stages: stage 1—anterior rectus sheath and stage 2—external oblique muscles. From the 12 patients, three presented early complications: seroma (n = 2) and epitheliolysis (n = 1). There were no recurrences or other late complications (48 months follow-up period). The separation of the anterior rectus sheath, and incision in the lateral recess to undermine the oblique muscles, allowed the treatment of abdominal wall defects, without late complications.

Simulated Moving Bed Technology: Overview and Use in Biorefineries

Synthesis of chemical compounds oftentimes produce a mixture of desired and undesired components. The ease of purification and recovery of the desired component more often than not determines the viability of the production technology. Simulated Moving Bed (SMB) technology is a continuous purification and separation technique with better performance (less solvent consumption and higher throughput) than traditional batch chromatography. SMB is a continuous separation technology which can be used to achieve the desired product purity with considerably lower power and raw material consumption. A lot of research and development is undergoing in the SMB technology which is enabling the search for more economical and carbon neutral ways of producing industrial chemicals. SMB has proven to be of great assistance in extracting products produced in biorefinery fermentation processes in an economical and energy efficient fashion. This chapter outlines the various processes the author has developed using SMB technology, its use in biorefineries, and prospective use in the future.