IDENTIFICATION OF ENERGY CONSERVATION POTENTIAL
IN EXISTING PLANTS
A. General
1.01 Energy saving is not new to the fertilizer industry. Efficient use of raw materials and energy is normally one of the main areas attended to by corporate and plant management, maintenance personnel and operators.Moreover, with the steep increase in fuel and raw material prices during the last decade, production techniques have been improved to achieve more
efficient feedstock and energy use, compared to the substantially less efficient plants commissioned 10-15 years ago. However, because of urgent pressures of plant operation, corporate and plant management had generally not paid adequate attention to energy conservation. Prevailing economic conditions now provide the impetus for adopting new methods and techniques to economize on inputs.
1.02 Energy conservation programs at the plant level need an organized and systematic approach if their full potential is to be realized. Effective plant organizational measures and energy audits are necessary to track down losses, to identify possible measurement anomalies, to evaluate audit results both technically and economically, and to work out detailed energy conservation programs. These programs will usually consist of two or three distinct parts: improved housekeeping and maintenance (needing little or no investment); short-term investment (revamping) programs; and long-term (reconstruction) programs. While organizational measures, energy audits and good housekeeping can be of general applicability to fertilizer plants, revamping and reconstruction measures are always process-specific.
B. Organizational Arrangements
1.03 The organizational arrangements needed at the plant level to collect the required energy consumption information, analyze it adequately to facilitate preparation of an energy efficiency program specific for each plant facility, and monitor the implementation of the identified program, are the following:
(a) Organize a General Energy Audit, along the lines discussed below, by in-house specialists or by an outside agency (an energy audit firm or consultants with expertise in this field is normally required where revamping is considered) based on which energy conservation measures and investments can be designed;
(b) Install an Energy Accounting System to initiate availability of energy utilization data on a regular basis. Initially this system may be rough and approximate, because a more accurate and detailed accounting system will be possible only after unit-by-unit energy audits have been carried out;
(c) Establish the Position of Energy Coordinator, who should be responsible either to the production manager or to the works manager. He should be a process engineer with reasonable
experience in the fertilizer industry. In addition, it would be desirable for the works manager and/or the production manager to attend a general course on energy saving methods.
(d) Initiate Unit-by-Unit Energy Audits as soon as everyone concerned becomes familiar with energy conservation. This analysis, under the supervision of the energy coordinator, should be made by a process technologist, and the energy accounting system referred to in (b) above should be refined for each unit studied. This is a step-by-step procedure,
explained further in the next section.
(e) Install a Follow-up Program based on the above audits, with clearly established improved energy consumption standards endorsed by the top management. A regular periodic energy
accounting is necessary to measure maintenance of these standards, enabling management to constantly monitor the use
of energy.
1.04 Organizationally, it is important to have one person in the company, the energy coordinator, as the focal point for all energy-saving activities. It is not necessary to create a department for energy saving.
In fact, the creation of such a department may be counter productive since the operating managers should retain the main responsibility and motivation to achieve energy savings in the plant. The energy coordinator could have an assistant, but may use the existing staff of the technological, engineering, maintenance and project departments, for project preparation and implementation. If these departments do not have the required level of inrhouse knowledge on energy conservation, outside consultants with knowledge of the process under scrutiny could be utilized.
C. General and Unit Energy Audits
1.05 Several of the larger chemical and fertilizer companies have worked out detailed energy audit procedures for whole complexes and individual units. In complexes where people are not yet sufficiently energy-conscious, it may be especially desirable to start with a general energy audit of the whole complex with the assistance of a specialized outside consulting firm or operating company.
1.06 As noted earlier, the next step is to carry out detailed energy audits of individual units, including offsites and services. These audits should be in adequate depth to result in the identification and evaluation of definite energy saving proposals. In these audits, the following
factors should be given close attention:
(a) Establish the overall economics of the plant and the desirability of energy saving. Even after energy savings are achieved, some of the older plants may still have consumption levels much higher than modern plants and the economic viability of the plant could be doubtful. In this case, it may be more appropriate to close down the plant.
(b) Make an energy balance of inputs and outputs (including drains, stacks, etc.) within about 5% accuracy, to locate major areas of loss and inefficiency, looking especially at the balance of available energy.
(c) Review broadly the plant energy audit with a team (coordinated by the audit leader) consisting of the plant manager, plant engineer, process manager and energy coordinator, to identify major energy saving potentials;
(d) Review in detail the energy audit with a larger team including foremen and specialists in addition to the members mentioned under (e) above; and
(e) Prepare an action program in which costs and benefits are carefully identified and taken into account.