Process Flow Scheme Research Articles

Ispra Mark 13A, a new process for flue gas desulphurization

Abstract A new regenerative wet scrubbing process for flue gas desulphurization, Ispra Mark 13A, is presented. The process produces two useful products, concentrated sulphuric acid and hydrogen. Process flow schemes and process principles are discussed.

Offshore Topside Facilities Optimization

Abstract Offshore topside facilities and supporting structure investments are generally substantial. Comprehensive front-end optimization studies are necessary to design the most cost-effective system which will be both flexible and efficient. This paper will discuss the development of an optimized topside facilities design for oil/gas production. Process optimization is perhaps the biggest weight and space saving technique. The paper will describe the objectives and areas of process optimization, and the factors that dictate the design and selection of optimum operating conditions for oil and gas process systems. When production is from two or more locations, centralized production and processing may reduce total investment costs. Discussions on the logical approach to determine the optimum development scenario are presented. The topsides designer Vias various means of predicting space and maintaining weight control. These options are outlined and flares structures are given as an example. The potential of new technology for reducing weight and space of standard equipment is explored. Introduction Offshore topside facilities generally use a design based on the simplest useable process in order to minimize equipment and utility requirements. This is to reduce platform weight and space. A simple process design may not be the most efficient or flexible choice. A design is however, often based on limited data and must have flexibility for other than design conditions. Since offshore production facilities and supporting structures investments are substantial, comprehensive front-end optimization studies are necessary to design the most cost effective system which will be both flexible and efficient. What is unique about offshore projects is their integrated nature; they are highly sensitive to the initial assumptions and decisions that are utilized to formulate the design. Process Optimization Process optimization is the primary weight and space saving technique. Typical offshore development plans start work on topside facilities process and utility design while the reservoir modelling is proceeding. Reservoir data such as: GOR, gas composition, produced water rate, etc., are known to change with time but design cannot proceed unless a basis can be established. Decisions must be made, and the uncertainties accounted for, by allowing for a design safety factor. Processing the produced oil and gas offshore requires some or all of the following systems:separation of the gas, oil condensate, and water phases;heating/cooling for wax/hydrate prevention, stabilization, storage, etc.;gas conditioning to meet pipeline dewpoint requirements;produced water treatment;gas compression for injection/export; andseawater treatment/injection. Commercial computer program packages are now available to simulate process design. These programs generally follow a building block approach and were originally developed for the chemical process industries but can very easily be adapted to simulate the oil/gas production process. The program is set to perform a heat and material balance for the desired process flow scheme to deliver the required stabilized crude or conditioned gas. Optimization is achieved by multiple simulations with different temperatures, pressures, number of process units (e.g. separation stages, heaters, coolers) to fulfill the following major objectives:

Alkaline treatment of wheat straw for increasing anaerobic biodegradability

Wheat straw was treated with NaOH and anaerobically digested for methane production. Alkaline treatment resulted in a greater than 100% increase in biodegradability of wheat straw. The potential of a process flow scheme employing high alkali concentration at ambient temperature with solids separation and recycle of filtrate containing residual alkali was explored. The effect of NaOH on the solubilization of cell wall constituents and potential problems of toxicity are discussed. A solubilization model was developed which is used to predict biodegradability of whole samples based on solids and filtrate biodegradabilities. Energy requirements and chemical costs are also addressed.

Status report on the operation of the bench-scale plant for hydrogen production by the mark-13 process

The bench-scale plant for thermochemical hydrogen production by the Mark-13 process has been successfully operated since May 1978. The nominal hydrogen production rate of the plant working at atmospheric pressure is 100 STP 1. h −1. A concise description of the process flow scheme is given. Operation of the plant demonstrated that thermochemical water decomposition is a viable process and a valid alternative to other processes for hydrogen production from water. The availability of the plant for experimental work was very high and no special start-up procedure was required. All reactions and product separation units were working within their specifications and no by-product formation was observed.