Adam S. Markowski

Fuzzy risk matrix.

A risk matrix is a mechanism to characterize and rank process risks that are typically identified through one or more multifunctional reviews (e.g., process hazard analysis, audits, or incident investigation). This paper describes a procedure for developing a fuzzy risk matrix that may be used for emerging fuzzy logic applications in different safety analyses (e.g., LOPA). The fuzzification of frequency and severity of the consequences of the incident scenario are described which are basic inputs for fuzzy risk matrix. Subsequently using different design of risk matrix, fuzzy rules are established enabling the development of fuzzy risk matrices. Three types of fuzzy risk matrix have been developed (low-cost, standard, and high-cost), and using a distillation column case study, the effect of the design on final defuzzified risk index is demonstrated.

QUALITY INTERACTION IN A JET SPOUTED BED DRYER FOR BIO-PRODUCTS

ABSTRACT An experimental study was conducted to apply the jet spouted bed (JSB) dryer with inert bodies for drying of fodder antibiotic; (zinc-salt bacitracin and tylosin) and bakers yeast which are extracted from fermentation broth. After establishing the drving properties of these products (e.g. sorption isotherm, water activity and thermostability), the influence of basic drying parameters (temperature of drying agent, bed loading, gas flow rate) on drying characteristics and quality of the products was determined. The results proved that a JSB dryer may be successfully applied to fodder antibiotics; especially to Zn-bacitracin; however, for a highly labile live organism like bakers yeast, this method cannot be used. The optimal parameters for drying of Zn-bacitracin have been presented.

Assessment of Safety Measures in Drying Systems

Fire and explosion hazards as well as safety measures encountered in drying processes are presented. Those data were used to work out a simplified layer of protection analysis (called dLOPA). In the developed method, necessary tools based on the matrix concept were presented. It concerns the assessment of an effective ignition source probability and severity of a possible consequence of dust explosion. A step-by-step procedure for dLOPA analysis is presented. This method may find application in risk assessment for workers exposed to explosive atmosphere (ATEX Directives).

Drying Risk Assessment Strategies

Abstract This article highlights drying risk assessment strategies showing details of the methodology involved and the various tools used at risk assessment. The methodology suggested is to apply qualitative risk assessment with risk estimation used for qualitative ranking of recommendations. The methodology suggested follows to a large extent the general procedure for risk assessment of machinery and the application of modified the “What-if” hazard method with the risk estimation by a multi-layer risk matrix technique. As an example, a case study of risk assessment for the typical two-stage spray-fluid bed dryer to produce milk powder is presented. The analysis shows how an acceptable risk level may be achieved by the introduction of risk reduction options.