Search results for " Softening"

Techno-economic assessment of multi-effect distillation process for the treatment and recycling of ion exchange resin spent brines

2019

Abstract A treatment chain including nanofiltration, crystallization and multi-effect distillation (MED) is for the first time proposed for the treatment of an effluent produced during the regeneration of Ion Exchange resins employed for water softening. The goal is to recover the minerals and to restore the regenerant solution to be reused in the next regeneration cycle. MED is the most crucial unit of the treatment chain from an economic point of view. A techno-economic analysis on the MED unit was performed and a novel performance indicator, named Levelized Brine Cost, was introduced as a measure of the economic feasibility of the process. Different scenarios were analysed, assuming diff…

A thermodynamically consistent formulation of nonlocal and gradient plasticity

1998

Recristallisation Dynamique au Cours de la Déformation à Chaud de Quatre Nuances de Bronze à 9% d'Etain

1995

Pour cerner les techniques metallurgiques des artisans protohistoriques, il est necessaire de connaitre les evolutions microstructurales obtenues selon les deformations imposees. La compression a chaud de deux bronzes industriels (contenant soit 0,026% soit 0,26% de zinc) et deux bronzes «archeologiques» (contenant soit 0,5% de soufre soit 0,5% de soufre et 0,5% de plomb) permet les observations suivantes : - Les comportements des bronzes «archeologiques» sont tres similaires : jusqu'a 600°C pour e = 0,1 on n'observe pas de recristallisation ; pour e = 1,2 on observe une recristallisation en collier le long des joints de grains. A 750°C la recristallisation semble homogene dans tout le mate…

Nonstationary flow surface theory for modeling the viscoplastic behaviors of soils

2016

Abstract This paper presents a three-dimensional elastic viscoplastic model that can describe the time-dependent behaviors of soft clays. The constitutive model is formulated based on the nonstationary flow surface theory and incorporates new developments, including (i) an improved definition of the nonstationary flow surface that is capable of capturing the stress–strain behaviors under different loading paths, (ii) a unique stress–strain—viscoplastic-strain-rate equation that is able to explicitly describe the nonstationary flow surface, and (iii) a final stable state concept that identifies the final equilibrium state at the end of creep and stress relaxation, which is also used to simpl…

Softening of Silica Filled Styrene-Butadiene Rubber under Uniaxial Cyclic Loading

2016

Stress-strain behaviour of silica filled styrene-butadiene rubber showed strong hysteresis and cyclic softening, while these effects were almost negligible for the neat rubber. Significant Mullins effect occurs between the first and second loading cycles, whereupon samples reach their steady state after four repeated cycles. The degree of softening increases with volume content of silica characterizing the softening effect as a breakdown of the filler-formed microstructure defined by both, specific interactions in the filler associations and between the filler and rubber matrix. Contribution of different damage mechanisms to the total energy losses on different stages of extension was estim…